Determination of trace amounts of Brown HT as a food dye by a CPE-scanometry method

AbstractIn this study, trace amounts of Brown HT were extracted, pre-concentrated and determined by cloud point extraction-scanometry (CPE-scanometry) as a simple, fast and inexpensive method. The procedure is based on CPE of Brown HT from an aqueous solution, diluting the extracted surfactant-rich phase with ethanol to 500μL, transferring the appropriate volume to Plexiglas® cells and scanning the cells. Then, the colour of each cell was analyzed by software written in visual basic (VB 6) into red, green and blue values. Effective parameters for the extraction efficiency, such as the pH of the system, the concentration of surfactant, the equilibration temperature and equilibration time, were investigated and optimized. Under optimal conditions, the calibration curve was linear in the range of 0.06–2.60mgL−1. The detection limit of the proposed method was 0.04mgL−1. In addition, the effects of some foreign species, including cations, anions and dyes, were investigated. The method was applied successfully for the determination of Brown HT in some water samples

Basal cell carcinoma treated successfully with combined CO2 laser and photodynamic therapy in a renal transplant patient: a case report

Renal transplant recipients are at significantly greater risk of developing skin malignancies due to combination immunosuppressive therapy. A significant number of patients present with lesions needing excision at multiple outpatient follow-up visits. For basal cell carcinoma, we have recently described how combining CO2 laser with Photodynamic therapy greatly increases the efficacy of long-term tumour clearance compared with each modality alone. We present a case of a 66-year-old renal transplant therapy patient who repeatedly presents with new skin malignancies, in whom we treated successfully with Laser-Photodynamic therapy in a see-and-treat setting. This therapy offers patients the possibility of better cosmetic and functional results whilst obviating the need for repeated surgery. Other pre-cancerous lesions such as solar keratoses are prevalent in this patient group and respond extremely well to Photodynamic therapy monotherapy. We propose a regular clinic for renal transplant patients in a laser facility equipped with CO2 laser and Photodynamic therapy, histopathology and punch-biopsy materials. This strategy allows simple and effective treatment of multiple lesions simultaneously, avoidance of numerous operations, avoidance of non-essential outpatient appointments that result in booking furthers visits for treatment, whilst facilitating diagnostic biopsies of potentially malignant lesions. We outline a care pathway for a see-and-treat clinic that implements this novel treatment modality improving the care of this unique patient population

Comparison of the effect of cycloplegic versus NSAID eye drops on pain after photorefractive keratectomy

Purpose: To compare the effect of Homatropine and Diclofenac eye drops for reducing pain after photorefractive keratectomy (PRK). Methods: This randomized, double-masked, interventional study included 32 patients (64 eyes) who underwent bilateral PRK. After operation, patients received Homatropine eye drops in one eye and Diclofenac eye drops in the fellow eye for 48 h. The level of pain was evaluated using visual analogue scale (VAS), verbal rating scale (VRS), and pain rating index (PRI) at 0.5, 24, and 48 h after operation. Results: The level of pain was statistically similar between the two eyes half an hour after operation; however, Diclofenac eyes had significantly less pain 24 h after operation (1.7 ± 1.4 vs 5.8 ± 2.1, P < 0.001 for VAS, 0.6 ± 0.6 vs 2.4 ± 1.1, P < 0.001 for VRS, and 3.4 ± 3.4 vs 12.0 ± 6.9, P < 0.001 for PRI, respectively). Also, 48 h after surgery, the pain scores were less in the Diclofenac eyes (1.6 ± 1.8 vs 3.4 ± 2.8, P < 0.001 for VAS, 0.6 ± 0.6 vs 1.2 ± 0.9, P < 0.001 for VRS, and 3.3 ± 3.7 vs 6.5 ± 6.2, P < 0.001 for PRI). No case with delayed epithelial healing in both groups was observed. Conclusion: The effect of Homatropine seems to be lower compared to Diclofenac for reducing pain after photorefractive keratectomy. © 2015 Iranian Society of Ophthalmology

Cytomegalovirus and toxoplasma gondii: Common causes of profound sensori neural hearing loss in children with cochlear implant surgery in a highly immune population: Tehran; Iran

Background: Iranian population is highly immune from T.Gondii and CMV infection. Objective: To determine the immunity to T.Gondii and CMV in children with the cochlear implant surgery accompanied with the profound Idiopathic type of SNHL Methods and Materials: We studied 45 cases with the cochlear implant surgery (Idiopathic profound SNHL) and 30 controls with the normal OAEs in a cross-sectional study in Rasoul Akram Hospital in Tehran (2010-2012). Blood samples (2 ml) were centrifuged and were kept frozen at-20°C. Sera searched for the specific antibodies against CMV and T.Gondii. The enzyme-linked immunosorbent assay (ELISA; BioChem Immune System) was calculated qualitatively. (P value< 0.05) Results: Range of age in cases with profound SNHL (<95 dB) was 6 months-to-14 years; mean=3.4+3.16 y; Idiopathic type of SNHL children diagnosed in 45 cases were younger than cases with non-Idiopathic SNHL (mean age=20 months; PV=0.05). Positive T.Gondii-IgM was found in 8 /45 (17.7) and also one of these cases (2.2) had positive T.Gondii �IgG test. Positive CMV-IgM & IgG were determined in 23 and 51 of cases, respectively. Positive T.Gondii �IgG was observed in 60 (18/30) of controls but none of them had positive T.Gondii � IgM. Positive CMV-IgM & IgG in controls was 3.3 and 90, respectively. Conclusion: CMV infection is one of the most common infections found in profound idiopathic SNHL children especially in younger cases (< 2 years) even in highly immune Iranian populations. Probably, T.Gondii infection has a relative role in younger cases with profound SNHL but a higher role in mild to moderate SNHL in our pediatric population. Most of the T.Gondii infected SNHL cases never require cochlear implant surgery. In future, a cohort study for prenatal diagnosis of the intrauterine infection and the role of infection in producing SNHLwould be very helpful. It has been recommended to search the specific antibodies against these two common infections in all types of SNHL in pediatric groups which are treatable especially in younger cases (<2 year). © 2019 Noorbakhsh et al

On Coding for Reliable Communication over Packet Networks

We present a capacity-achieving coding scheme for unicast or multicast over lossy packet networks. In the scheme, intermediate nodes perform additional coding yet do not decode nor even wait for a block of packets before sending out coded packets. Rather, whenever they have a transmission opportunity, they send out coded packets formed from random linear combinations of previously received packets. All coding and decoding operations have polynomial complexity. We show that the scheme is capacity-achieving as long as packets received on a link arrive according to a process that has an average rate. Thus, packet losses on a link may exhibit correlation in time or with losses on other links. In the special case of Poisson traffic with i.i.d. losses, we give error exponents that quantify the rate of decay of the probability of error with coding delay. Our analysis of the scheme shows that it is not only capacity-achieving, but that the propagation of packets carrying "innovative" information follows the propagation of jobs through a queueing network, and therefore fluid flow models yield good approximations. We consider networks with both lossy point-to-point and broadcast links, allowing us to model both wireline and wireless packet networks.Comment: 33 pages, 6 figures; revised appendi

Negative Energies in the Dirac equation

It is easy to check that both algebraic equation Det (hat p - m) =0 and Det (hat p + m) =0 for u- and v- 4-spinors have solutions with p_0= pm E_p = pm sqrt bf p^2 +m^2. The same is true for higher-spin equations. Meanwhile, every book considers the equality p_0=E_p for both u- and v- spinors of the (1/2,0)+(0,1/2)) representation only, thus applying the Dirac-Feynman-Stueckelberg procedure for elimination of the negative-energy solutions. The recent Ziino works (and, independently, the articles of several others) show that the Fock space can be doubled. We re-consider this possibility on the quantum field level for both s=1/2 and higher spin particles.Comment: 8 pages, no figures. Accepted in Zeitschrift fur Naturforschun

Irregular behaviour of class numbers and Euler-Kronecker constants of cyclotomic fields: the log log log devil at play

Kummer (1851) and, many years later, Ihara (2005) both posed conjectures on invariants related to the cyclotomic field $\mathbb Q(\zeta_q)$ with $q$ a prime. Kummer's conjecture concerns the asymptotic behaviour of the first factor of the class number of $\mathbb Q(\zeta_q)$ and Ihara's the positivity of the Euler-Kronecker constant of $\mathbb Q(\zeta_q)$ (the ratio of the constant and the residue of the Laurent series of the Dedekind zeta function $\zeta_{\mathbb Q(\zeta_q)}(s)$ at $s=1$). If certain standard conjectures in analytic number theory hold true, then one can show that both conjectures are true for a set of primes of natural density 1, but false in general. Responsible for this are irregularities in the distribution of the primes. With this survey we hope to convince the reader that the apparently dissimilar mathematical objects studied by Kummer and Ihara actually display a very similar behaviour.Comment: 20 pages, 1 figure, survey, to appear in `Irregularities in the Distribution of Prime Numbers - Research Inspired by Maier's Matrix Method', Eds. J. Pintz and M. Th. Rassia

Statistical Mechanics Analysis of LDPC Coding in MIMO Gaussian Channels

Using analytical methods of statistical mechanics, we analyse the typical behaviour of a multiple-input multiple-output (MIMO) Gaussian channel with binary inputs under LDPC network coding and joint decoding. The saddle point equations for the replica symmetric solution are found in particular realizations of this channel, including a small and large number of transmitters and receivers. In particular, we examine the cases of a single transmitter, a single receiver and the symmetric and asymmetric interference channels. Both dynamical and thermodynamical transitions from the ferromagnetic solution of perfect decoding to a non-ferromagnetic solution are identified for the cases considered, marking the practical and theoretical limits of the system under the current coding scheme. Numerical results are provided, showing the typical level of improvement/deterioration achieved with respect to the single transmitter/receiver result, for the various cases.Comment: 25 pages, 7 figure

Acute nonbacterial gastroenteritis in hospitalized children: A cross sectional study

Background: Viral acute gastroenteritis (AGE) is a major cause of morbidity in childhood and leads to hospitalization in developed countries, such as Iran. Objectives: The aim of this study was to determine the prevalence and viral types (rotavirus, adenovirus, human parechoviruses-1, and human bocavirus) of acute nonbacterial gastroenteritis in hospitalized children. Patients and Materials: This was a across-sectional prospective study performed at the Pediatric Department of Rasoul Hospital, Tehran, Iran (2009-2011) on 80 hospitalized children with viral AGE. All Stool samples were collected on viral transport media. Human bocavirus (HBoV) was detected using the Real-time PCR TaqMan method. Molecular detection of human parechovirus type 1 (HPeV-1) RNA in stool samples was done using a specific nested reverse transcription PCR (RT-PCR). Rota and adeno virus antigens were sought by rapid chromatographic tests. P values less than 0.05 were considered statistically significant. Results: Fever was determined in 47.5 of cases (38), nausea and vomiting in 42.5 (34), respiratory symptoms in 16.3 (13), abdominal pain in 76. Duration of diarrhea was 1-30 days (mean = 6.3 + 4.3 days). No dehydration was observed in 43.5 of subjects, mild dehydration in 33.8, moderate dehydration in 17.5 and severe dehydration in 5 of cases. Positive rotavirus was found in 48.8 of cases (39), adenovirus in 20 (16), HBoV in 8 (6) and HPeV-1 in 23.2 (19), and adeno and rotaviruses co-infection in 6 (4). The frequency of positive HBoV was significantly lower than adeno and rotaviruses infection (P value = 0.0001). Rotavirus was more frequent in males (P value = 0.003) and in young children (17.49 months vs. 21.44 months) P value = 0.03, CI = -13.4, 5.5. Rotavirus infection was related to the degree of dehydration (P value = 0.001) but was not related to the presence of vomiting or fever (P value > 0.5). Conclusions: This study indicates that viral agents, especially rotavirus (48.8%), HPeV-1 (23.2%) and adenovirus (20%) are the most important causes for viral AGE in children while HBoV (8%) is infrequent during childhood. Determination of various viral pathogens of AGE is very important in planning diarrhea disease control strategies in our country where rotavirus vaccination in not routinely used. © 2014, Ahvaz Jundishapur University of Medical Sciences