Harmonic current extraction of shunt active power filter based on prediction current technique - Hysteresis PWM

Due to the wide spread of power electronics equipment in modern electrical systems, the increase of the harmonics disturbance in the ac mains currents has became a major concern due to the adverse effects on all analysis and simulation using MATLAB-SIMULINK of a three-phase shunt active equipment. This paper presents the Shunt Active Power Filter (SAPF) to compensate the generated harmonics by 3-phase Rectifier Bridge fed R-L load. The harmonic current extraction is based on prediction current extraction technique -hysteresis PWM generation pattern

Simultaneous detection of respiratory syncytial virus types A and B and influenza virus types A and B in community-acquired pneumonia by reverse transcription-multiplex PCR

Background: Respiratory syncytial virus (RSV) types A and B and influenza A and B cause about 80–90% of viral lower respiratory tract infections. It is impossible to distinguish the cause of viral respiratory infections by their clinical presentation. Multiplex RT-PCR has a significant advantage in that it permits the simultaneous amplification of several viruses in a single reaction facilitating cost-effective diagnosis and perhaps improved clinical management.Objectives: In this study, our aim was to determine the prevalence of influenza A and B, and RSV types A and B among children with CAP, by the use of the newly developed rapid, accurate, and pathogen-specific technique of multiplex RT-PCR in order to accomplish the greatest positive effect on patient care and health care costs.Study methodology: This study is a cross-sectional study involving 24 children admitted to the Children’s Hospital of the Ain Shams University due to severe lower respiratory tract infection (LRTI). Clinical and radiological assessment of all patients was performed followed by the molecular analysis of both respiratory and blood samples of all enrolled patients simultaneously by the use of the newly available reverse transcription-multiplex PCR technique (RT-m PCR).Results: Viral pneumonia was detected in one-third of enrolled patients (8/24), with the predominance of respiratory syncytial virus A (4/8), followed by influenza A virus (3/8) and influenza B virus (1/8) while no cases of respiratory syncytial virus B was detected. The same results were identified in both blood and respiratory specimens.Conclusion: Reverse transcription-multiplex PCR technique – multiplex has a significant advantage in that it permits the simultaneous amplification of several viruses in a single reaction making it well suited for use in epidemiological studies and to improve etiology-directed clinical management of viral pneumonia.Keywords: Viral pneumonia; LRTI; Children; Reverse transcription-multiplex PCR; RSV; Influenza viruse

VAMPIRE® fundus image analysis algorithms:Validation and diagnostic relevance in hypertensive cats

OBJECTIVES: To validate a retinal imaging software named VAMPIRE® (Vascular Assay and Measurement Platform for Images of the Retina) in feline patients and test the clinical utility in hypertensive cats. ANIMALS STUDIED: One hundred and five healthy cats were enrolled. They represented the normal dataset used in the validation (group 1). Forty-three hypertensive cats with no noticeable retinal abnormalities were enrolled for the clinical validity of the software (group 2). PROCEDURES: Eleven points (4 veins, 4 arteries, and 3 arterial bifurcations) were measured for each digital image. Repeatability and reproducibility of measurements were assessed using two independent operators. Data were statistically analyzed by the Mann-Whiney and Tukey box plot. Significance was considered when P < 0.05. RESULTS: Two hundred and ten retinal images were analyzed for a total of 2310 measurements. Total mean was 9.1 and 6.1 pixels for veins and arteries, respectively. First, second, and third arteriolar bifurcations angles were 73.6°, 76.9°, and 85.4°, respectively. A comparison between groups 1 and 2 showed a statistically significant reduction in arteriolar diameter (mean 3.3 pixels) and branch angle (55°, 47.8° and 59.9°) associated with increasing vein diameter (mean 24.15 pixels). CONCLUSIONS: Current image analysis techniques used in human medicine were investigated in terms of extending their use to veterinary medicine. The VAMPIRE® algorithm proved useful for an objective diagnosis of retinal vasculature changes secondary to systemic hypertension in cats, and could be an additional diagnostic test for feline systemic hypertension

Biochemical and histological evidences for the antitumor potential of Teucrium Oliverianum and Rhazya stricta in chemically-induced hepatocellular carcinoma

Background: Teucrium oliverianum and Rhazya stricta are medicinal plants used in traditional and herbal medicine for the treatment of diabetes, liver diseases and inflammatory conditions. The present study was planned to investigate the antitumor efficacy of Teucrium oliverianum and Rhazya stricta in chemically-induced hepatocellular carcinoma (HCC) in rats.Materials and Methods: Forty adult male rats weighing 170-200 g were divided into four groups; each group was comprised of ten rats: (1): Normal healthy animals served as negative control group, (2):  Hepatocellular carcinoma (HCC) group in which the rats were orally administered Nnitrosodiethylamine (dissolved in 0.9% normal saline), in a dose of 20 mg/kg b.wt. five times a week for six weeks, (3): HCC group treated with Teucrium oliverianum extract in a dose of 600 mg/kg b.wt for two months and (4): HCC group treated with Rhazya stricta extract in a dose of 750 mg/kg b.wt for two months. Serum alanine  aminotransferase (ALT), asparatate aminotransferase (AST), alkaline phosphatase (ALP) and  gammaglutamyl transferase (γ-GT) activities were estimated. Serum  carcinoembyronic antigen (CEA), alpha-fetoprotein (AFP), alpha-L-fucosidase (AFU), glypican-3 (GPC-3), golgi protein 73 (Gp-73) and vascular endothelial growth factor (VEGF) levels were determined. Histopathological examination of liver tissue sections was also carried out.Results: The HCC group showed significant elevation in serum AST, ALT, ALP and γ-GT activities as well  as CEA, AFP, AFU, Gpc-3, Gp 73 and VEGF levels versus the negative control group. Photomicrograph of liver tissue sections of rats in HCC revealed hepatic parenchyma with foci of anaplastic hepatocellular carcinoma as well as other foci of cystic cholangio carcinoma associated with areas of telangictasis with haemorrhage as well as individual hepatocellular necrosis.Conclusion: Treatment of HCC groups with Teucrium oliverianum or Rhazya stricta extract experienced significant improvement in the measured biochemical parameters as well as in the structural  organization of the liver. In conclusion, the current study provided experimental evidences for the antitumor efficacy of Teucrium oliverianum and Rhazya stricta against hepatocellular carcinoma. Such effect could be attributed to hepatoprotective properties, antiproliferative activity and antiangiogenic potential.Keywords: Hepatocellular carcinoma, Teucrium oliverianum, Rhazya stricta, rat

The effect of Gonioscopy on keratometry and corneal surface topography

BACKGROUND: Biometric procedures such as keratometry performed shortly after contact procedures like gonioscopy and applanation tonometry could affect the validity of the measurement. This study was conducted to understand the short-term effect of gonioscopy on corneal curvature measurements and surface topography based Simulated Keratometry and whether this would alter the power of an intraocular lens implant calculated using post-gonioscopy measurements. We further compared the effect of the 2-mirror (Goldmann) and the 4-mirror (Sussman) Gonioscopes. METHODS: A prospective clinic-based self-controlled comparative study. 198 eyes of 99 patients, above 50 years of age, were studied. Exclusion criteria included documented dry eye, history of ocular surgery or trauma, diabetes mellitus and connective tissue disorders. Auto-Keratometry and corneal topography measurements were obtained at baseline and at three follow-up times – within the first 5 minutes, between the 10(th)-15(th )minute and between the 20(th)-25(th )minute after intervention. One eye was randomized for intervention with the 2-mirror gonioscope and the other underwent the 4-mirror after baseline measurements. t-tests were used to examine differences between interventions and between the measurement methods. The sample size was calculated using an estimate of clinically significant lens implant power changes based on the SRK-II formula. RESULTS: Clinically and statistically significant steepening was observed in the first 5 minutes and in the 10–15 minute interval using topography-based Sim K. These changes were not present with the Auto-Keratometer measurements. Although changes from baseline were noted between 20 and 25 minutes topographically, these were not clinically or statistically significant. There was no significant difference between the two types of gonioscopes. There was greater variability in the changes from baseline using the topography-based Sim K readings. CONCLUSION: Reversible steepening of the central corneal surface is produced by the act of gonioscopy as measured by Sim K, whereas no significant differences were present with Auto-K measurements. The type of Gonioscope used does not appear to influence these results. If topographically derived Sim K is used to calculate the power of the intraocular lens implant, we recommend waiting a minimum of 20 minutes before measuring the corneal curvature after gonioscopy with either Goldmann or Sussman contact lenses

Clinical spectum of tuberculous optic neuropathy

Purpose Tuberculous optic neuropathy may follow infection with Mycobacterium tuberculosis or administration of the bacille Calmette–Guerin. However, this condition is not well described in the ophthalmic literature. Methods Ophthalmologists, identified through professional electronic networks or previous publications, collected standardized clinical data relating to 62 eyes of 49 patients who they had managed with tuberculous optic neuropathy. Results Tuberculous optic neuropathy was most commonly manifested as papillitis (51.6 %), neuroretinitis (14.5 %), and optic nerve tubercle (11.3 %). Uveitis was an additional ocular morbidity in 88.7 % of eyes. In 36.7 % of patients, extraocular tuberculosis was present. The majority of patients (69.4 %) had resided in and/or traveled to an endemic area. Although initial visual acuity was 20/50 or worse in 62.9 % of 62 eyes, 76.7 % of 60 eyes followed for a median of 12 months achieved visual acuities of 20/40 or better. Visual field defects were reported for 46.8 % of eyes, but these defects recovered in 63.2 % of 19 eyes with follow-up. Conclusion Visual recovery from tuberculous optic neuropathy is common, if the diagnosis is recognized and appropriate treatment is instituted. A tuberculous etiology should be considered when evaluating optic neuropathy in persons from endemic areas.Research to Prevent Blindness (unrestricted grant to Casey Eye Institute) provided partial support for this work

Correction: Metal complexes as a promising source for new antibiotics

Correction for ‘Metal complexes as a promising source for new antibiotics’ by Angelo Frei et al., Chem. Sci., 2020, 11, 2627–2639

Correlates of low birth weight in term pregnancies: a retrospective study from Iran

<p>Abstract</p> <p>Background</p> <p>Low birth weight (LBW) is considered as a major multifaceted public health concern. Seventy-two percent of LBW infants are born in Asia. An estimation of 8% LBW infants has been reported for Eastern Mediterranean region including Iran. This study investigated contributory factors of LBW in singleton term births in Tehran, Iran. Tehran is a multicultural metropolitan area and a sample from the general population in Tehran could be regarded as a representative sample of urban population in Iran.</p> <p>Methods</p> <p>This was a retrospective study using data from 15 university maternity hospitals in Tehran, Iran. Data on all singleton term births in these hospitals were extracted from case records during a one calendar year. Study variables included: maternal age, maternal educational level, history of LBW deliveries, history of preterm labor, cigarette smoking during pregnancy, number of parities, chronic diseases and residential area (Tehran versus suburbs of Tehran). In order to examine the relationship between LBW and demographic and reproductive variables the adjusted logistic regression analysis was performed.</p> <p>Results</p> <p>In all, data for 3734 term pregnancies were extracted. The mean age of women was 25.7 (SD = 5.3) years and 5.2% of term births were LBW. In addition to association between LBW and maternal age, significant risk factors for LBW were: history of LBW deliveries [adjusted odds ratio (OR) = 2.53, 95% confidence interval (CI) = 1.06–6.03], smoking during pregnancy (OR = 4.64, 95% CI = 1.97–10.95) and chronic diseases (OR for hypertension = 3.70, 95% CI = 2.25–6.06, OR for others = 2.04, 95% CI = 1.09–3.83).</p> <p>Conclusion</p> <p>The findings indicate that in addition to maternal age, history of LBW deliveries; smoking during pregnancy and chronic diseases are significant determinants of LBW in this population. This is consistent with national and international findings indicating that maternal variables and risk behaviors during pregnancy play important roles on LBW.</p