182 research outputs found
Design and simulation of high frequency colpitts oscillator based on BJT amplifier
Frequency oscillator is one of the basic devices that can be used in most electrical, electronics and communications circuits and systems. There are many types of oscillators depending on frequency range used in an application such as audio, radio and microwave. The needed was appeared to use high and very high frequencies to make the rapid development of advanced technology Colpitts oscillator is one of the most common types of oscillator, it can be used for radio frequency (RF), that its output signal is often utilized at the basic of a wireless communication system in most application. In this research, a Colpitts oscillator is comprised from a bipolar junction transistor (BJT) amplifier with LC tank. This design is carrying out with a known Barkhausen criterion for oscillation. Firstly, is carried out using theoretical calculation. The secondary is carried out using simulation (Multisim 13). All the obtained result from the above two approaches are 10 MHz and 9.745 MHz respectively. This result is seen to be very encouraging
Degradation of crude oil and pure hydrocarbon fractions by some wild bacterial and fungal species
The use of biodegradation as a method for cleaning up soil that has been
contaminated by spilt petroleum can be an effective strategy. So, this study
investigated the existence of the wild microorganism in soil contaminated with
oil and study their ability to degrade petroleum in vitro. Nineteen samples
were collected from various locations near Taq Taq (TTOPCO) natural seeps in
the Kurdistan Region of Iraq. Morphological, cultural, biochemical tests and
molecular identification were used to identify the microbial communities, in
addition, spore texture and the colour of the fungal isolates were investigated
on the fungal isolates. Out of the19 samples, 17 indigenous bacterial strains
and 5 fungal strains were successfully isolated. From the absorption
spectrophotometry, Bacillus anthracis, Bacillus cereus, Achromobacter sp. and
Pseudomonas aeruginosa for the bacterial isolates grew well on a minimal salt
medium supplemented with 1% crude oil. Results showed that these isolates
mentioned above had a strong ability to degrade crude oil by reducing the
colour of 2,6-dichlorophenol indophenol (DCPIP) from deep blue to colourless.
However, for the fractions of hydrocarbon, the bacterial isolates failed and
did not affect the colour of any of the fractions. The results for fungi showed
that Aspergillus lentulus and Rhizopus arrhizus had a strong ability to degrade
both crude oil and fraction F1 by reducing the colour of DCPIP. Each fungal
isolates also had a great tolerance to different concentrations of crude oil
when grown on solid MSM. This study showed these microorganisms have a strong
ability to degrade crude oil and can be used to clean up soil and the
environment
HYPOLIPIDEMIC AND ANTI-FATTY LIVER EFFECTS EXERTED BY STANDARDIZED PUNICA GRANATUM L. PEEL EXTRACT IN HEPG2 CELL-LINE AND HIGH-FAT DIET-INDUCED MICE
Objective: Pomegranate, (Punica granatum L., Lythraceae) peel has concentrated amounts of lipid-lowering elements that demonstrated, in various hoary and recent studies, their effects against obesity and hyperlipidemia, which involves elevated rates of lipid and lipoprotein levels in blood and increases risks of cardiovascular diseases.We aim to study expression modulation of genes involved in lipid metabolism by the impact of standardized pomegranate peel extract (PPE) in a comprehensive research on human liver cells and experimental mice.Methods: Using reverse-transcription real-time PCR, an in vitro study harnessing HepG2 cell line was conducted to determine the hyperlipidemia-related gene expression profiles and cytotoxic effects upon treatment with PPE. In another complementary in vivo study, male C57BL/6J mice were fed a high-fat diet (HFD) or an HFD supplemented with PPE for 14 d to define the expression of lipid metabolism related genes that control obesity. Fatty liver proportions were also estimated after treatment.Results: Higher mRNA expression of LDL receptor (LDL-R) and down-regulation of sterol regulatory element-binding protein (SREBF-2), (SRBEP-1c), Fatty acid synthase (FAS) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) upon PPE treatment in HepG2 cell line were significantly recorded. In vivo study indicated significant weight reduction of body and liver, besides amelioration of fatty liver state detected by histological analysis. Moreover, the reverse-transcription real-time PCR assay demonstrated suppression (FAS) expression and up regulation of hormone sensitive lipase (HSL) in mice isolated liver and white adipose tissues.Conclusion: Our study manages to affirm the hypolipidemic and anti-fatty liver influence of Punica granatum L. peel extract, reflected by molecular evaluation above and beyond other physiological assays.Keywords: Pomegranate, Peel extract, Hyperlipidemia, LDLR, SREBP, FAS, HMGCR, HS
Can frozen-section analysis of ureteric margins at the time of radical cystectomy predict upper tract recurrence?
Objective: To summarise the currently available literature and analyse available results of the outcome of intraoperative frozen-section analysis (FSA) on upper urinary tract recurrence (UUTR) after radical cystectomy (RC).
Materials and methods: A systematic review of the literature was performed according to the Cochrane Reviews guidelines and in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Articles discussing ureteric FSA with RC were identified.
Results: The literature search yielded 21 studies, on which the present analysis was done. The studies were published between 1997 and 2019. There were 10 010 patients with an age range between 51 and 95 years. Involvement of the ureteric margins was noted in 2–9% at RC. The sensitivity and specificity of FSA were ~75% and 99%, respectively. Adverse pathology on FSA and on permanent section, prostatic urothelial carcinoma involving the stroma but not prostatic duct, and ureteric involvement on permanent section were all more likely to develop UUTR. Neither evidence of ureteric involvement nor ureteric margin status on permanent section were significant predictors of overall survival.
Conclusion: Routine FSA is mandatory for a tumour-free uretero–enteric anastomosis and is predictive of UUTR. To lower the UUTR, FSA is not necessary if the ureters are resected at the level where they cross the common iliac vessels. FSA is indicated whenever the surgeon encounters findings suspicious of malignancy, e.g. ureteric obstruction, periureteric fibrosis, diffuse carcinoma in situ, induration or frank tumour infiltration of the distal ureter is discovered unexpectedly during surgery, and prostatic urethral involvement.
Abbreviations CIS: carcinoma in situ; FSA: frozen-section analysis; HR: hazard ratio; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; RC: radical cystectomy; (UT)UC: (upper tract) urothelial carcinoma; UUT(R): upper urinary tract (recurrence)
Non-Steroidal Anti-Inflammatory Drugs and Antibiotics Prescription Trends at a Central West Bank Hospital
Objectives: We aimed to reliably describe the pattern of outpatient prescription of non-steroidal anti-inflammatory drugs (NSAIDs) and antibiotics (ATBs) at a central hospital in the West Bank, Palestine.Methods: This was a retrospective, cross-sectional study investigating a cohort of 2,208 prescriptions ordered by outpatient clinics and the emergency room over one year in Beit Jala Hospital in Bethlehem, West Bank. The orders were analysed for the rate and types of NSAIDs and ATBs utilised, and the appropriateness of these drugs to the diagnosis. Results: Of the total prescriptions, 410 contained NSAIDs (18.6%), including diclofenac (40.2%), low dose aspirin (23.9%), ibuprofen (17.8%) and indomethacin (15.1%). A minority of these prescriptions contained a combination of these agents (2.5%). Only one prescription contained cyclooxyeganse-2 inhibitors (0.2%). The appropriateness of NSAID use to the diagnosis was as follows: appropriate (58.3%), inappropriate (14.4%) and difficult to tell (27.3%). The rate of ATB use was 30.3% (669 prescriptions). The ATBs prescribed were amoxicillin (23.3%), augmentin (14.3%), quinolones (12.7%), first and second generation cephalosporins (9.4% and 12.7%, respectively) and macrolides (7.2%). ATB combinations were identified in 9.4%, with the most common being second-generation cephalopsorins and metronidazole (4.3%). Regarding the appropriateness of prescribing ATBs according to the diagnosis, it was appropriate in 44.8%, inappropriate in 20.6% and difficult to tell in 34.6% of the prescriptions. Conclusion: These findings revealed a relatively large number and inappropriate utilisation of ATBs and NSAIDs. An interventional programme needs to be adopted to reinforce physicians’ knowledge of the rational prescription of these agents
Phylogenetic characterization of two echinoid species of the southeastern Mediterranean, off Egypt
AbstractIn this study we investigated the phylogenetics of two sea urchin species, Arbacia lixula and Paracentrotus lividus from the Mediterranean Sea. Specimens were collected from the east coast of Alexandria City, Egypt. Pigmentation examination showed four sympatric color morphotypes (black, purple, reddish brown, and olive green). Mitochondrial DNA was extracted from specimens and mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal RNA (16S) were sequenced. The results showed that all black specimens constituted the species A. lixula. All other colors belonged to P. lividus, with no apparent differentiation between color morphotypes. Moreover, P. lividus showed high haplotype diversity (COI; H=0.9500 and 16S; H=0.8580) and low values of nucleotide diversity (COI; π=0.0075 and 16S; π=0.0049), indicating a high degree of polymorphism within this species. This study represents the first attempt at DNA barcoding of echinoid species in the southeast Mediterranean off the Egyptian coast, and will provide a base for future phylogenetic analyses
Cone-driven strong flash electroretinograms in healthy adults: Prevalence of negative waveforms
Purpose
Both rod and cone-driven signals contribute to the electroretinogram (ERG) elicited by a standard strong flash in the dark. Negative ERGs usually reflect inner retinal dysfunction. However, in diseases where rod photoreceptor function is selectively lost, a negative waveform might represent the response of the dark-adapted cone system. To investigate the dark-adapted cone-driven waveform in healthy individuals, we delivered flashes on a dim blue background, designed to saturate the rods, but minimally adapt the cones.
Methods
ERGs were recorded, using conductive fibre electrodes, in adults from the TwinsUK cohort. Responses to 13 cd m−2 s white xenon flashes (similar to the standard DA 10 flash), delivered on a blue background, were analysed. Photopic and scotopic strengths of the background were 1.3 and 30 cd m−2, respectively; through a dilated pupil, this is expected to largely saturate the rods, but adapt the cones much less than the standard ISCEV background.
Results
Mean (SD) participant age was 62.5 (11.3) years (93% female). ERGs from 203 right and 204 left eyes were included, with mean (SD) b/a ratios of 1.22 (0.28) and 1.18 (0.28), respectively (medians, 1.19 and 1.17). Proportions with negative waveforms were 23 and 26%, respectively. Right and left eye b/a ratios were strongly correlated (correlation coefficient 0.74, p < 0.0001). We found no significant correlation of b/a ratio with age.
Conclusions
Over 20% of eyes showed b/a ratios less than 1, consistent with the notion that dark-adapted cone-driven responses to standard bright flashes can have negative waveforms. The majority had ratios greater than 1. Thus, whilst selective loss of rod function can yield a negative waveform (with reduced a-wave) in some, our findings also suggest that loss of rod function can occur without necessarily yielding a negative ERG. One potential limitation is possible mild cone system adaptation by the background
Impact of family structure and sociodemographic characteristics on parents headed families in Ramadi City, Iraq
Background: Several factors in the family profile contribute significantly to determining the effective policy when heading the family. This study aims to evaluate the sociodemographic and economic burdens on parents-headed families in Ramadi City, west of Iraq.
Methods: A prospective cross-sectional household-based survey was conducted from 1st to 28th February 2019 among Iraqi people residents in Ramadi city, Anbar province. A multistage sampling technique was recruited to identify the eligible sample. A semi-structured questionnaire was used to interview (face-to-face) the respondents. Data from 267 households have undergone univariate and bivariate analyses. Multiple logistic regression, odds ratio (OR), and confidence intervals (CIs) were estimated to explore the predicting variables. The statistically significant is considered at less than 0.05.
Results: The mean age of respondents was 43.88 (± 12.1) years (range: 25 to 69 years). Out of the total surveyed people, 52.8% were young (less than 44 years), male-headed families (59.6%), low educated level (65.5%), unemployed (52.4%), married (67.4%) and headed big families of seven members and above (43.1%). History of chronic diseases and smoking habits was positive among 46.4% and 45.7% of respondents, respectively. Findings of the binary logistic regressions showed that history of smoking (OR = 7.201, 95% CI: 3.254 to15.936), families of 7 members and above (OR = 6.239, 95% CI: 2.938 to 13.250), unhappy (OR = 5.237, 95% CI: 2.140 to 12.818), aged 44 years and above (OR = 3.518, 95% CI: 1.581 to 7.829), being single (unmarried, divorced, widow) (OR = 2.697, 95% CI: 1.230 to 5.914), and had a monthly income of less than USD400 (OR = 2.333, 95% CI: 1.112 to 4.859) are significantly associated with female-headed family.
Conclusion: Priority must be given to some elements such as genetic, physical differences, biopsychosocial factors, and the economic situation when discussing parents' behavior in heading the family
Spontaneous Weight Change during Chronic Hepatitis C Treatment: Association with Virologic Response Rates
Objective: We examined weight changes during chronic hepatitis C (CHC) therapy and association with virologic response.
Methods: Weight changes were compared between subjects achieving rapid, early, and sustained virologic response rates (RVR, EVR, and SVR). RVR, EVR and SVR were compared among patients with or without weight loss of ≥ 0.5 body mass index (BMI) units (kg/m2) at 4, 12, 48 weeks.
Results: CHC therapy was initiated in 184 cases. Median pretreatment BMI was 27.7 (18.4-51.3) with 38% overweight and 31% obese (BMI ≥25 and ≥ 30, respectively). Among patients with liver biopsies (n = 90), steatosis was present in 31.6%; fibrosis grade of 1-2/6 in 46%, 3-4 in 37.3% and 5-6 in 14.7%. Mean weight loss at 4, 12, 24 and 48 weeks of therapy were 1.2, 2.6, 3.8 and 3.3 kg, respectively. After 4 and 12 weeks of treatment, 38% and 54.3% had a BMI decrement of ≥ 0.5 kg/m2. For genotype 1, weight loss at 4 weeks was associated with significantly higher EVR (90.0% vs. 70%, p = 0.01) and a tendency towards better RVR and SVR (42.9% vs. 26.0% and 55.2% vs. 34.8%, respectively, p = 0.08). In multivariate analysis, weight loss at 4 weeks was independently associated with EVR (OR 6.3, p = 0.02) but was not significantly associated with RVR or SVR
Conclusions: Spontaneous weight loss at 4 and 12 weeks of CHC therapy was associated with improved EVR. Weight loss at 4 weeks was an independent predictor of EVR but not SVR
- …