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

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

TELL and the English classroom: A Saudi Perspective

The intersection of technology and education has precipitated transformative changes globally, with Technology-Enhanced Language Learning (TELL) emerging as a dynamic and evolving field. In this literature review, we delve into the trends, developments, and prospects of TELL within the specific context of Saudi Arabia

TELL and the English classroom: A Saudi Perspective

Synopsis of a literature revie

Towards an effective environmental impact assessment (EIA) in the industrial sector of Bahrain, Arabian Gulf

Rapid economic and industrial developments and population growth in Bahrain are associated with increases in energy demand and greenhouse gas emissions. An Environmental Impact Assessment (EIA) process has been adopted in the country to address environmental aspects within energy intensive projects such as oil and petrochemical industries. The quality of EIA reports with respect to energy conservation and gas emissions was investigated in this study. The results obtained showed that aspects of gas emissions received more attention than energy conservation. The reports reflected a good (75%) and satisfactory (25%) consideration of air quality. Considering the efficiency and energy consumption aspects, the reports were assessed as satisfactory (25%), borderline (50%) and poor (25%) quality. A framework to be used as a platform to integrate the EIA process, environmental management systems (EMS) and energy management systems (EnMS) was suggested. Enforcement of legislations to ensure efficient use of energy within the industrial sector, adopting strategic environmental assessment (SEA) practice in the country and linking it to energy planning, and encouraging industrial firms to adopt EnMS to play the role of adhering to EIA mitigation measures were recommended

Indoor and Outdoor Volatile Organic Compounds at Office Buildings in Kuwait

A total of 800 indoor (I) and outdoor (O) air samples from eight large office buildings (LOBs) were analyzed for 78 VOCs using the latest sampling and preconcentration technology. Of these VOCs, 73 and 66 were detected in the I and O samples, respectively, at various levels and proportions. The I/O ratios were > 1, and ethanol exhibited the highest ratio of 14.7. The levels of aliphatic hydrocarbons were higher in LOBs located in the southern region of Kuwait, where the majority of industrial activities are located. By contrast, these levels were significantly lower in LOBs located in the northern and far northern regions, where industrial activities are absent. There was evidence of CFCs leaking from HVAC systems in several of the LOBs. BTEX inter-species ratios suggest that vehicular emissions contributed less to the outdoor air composition at the LOB at Jahra compared to other LOBs. Alcohols and carbonyls were the first and second most abundant classes of chemicals, respectively, in the VOC mixtures at the LOBs. None of the VOCs exceeded the recommended air quality limits

Detection of Enteric Viruses and Bacterial Indicators in a Sewage Treatment Center and Shallow Water Bay

The incidence of enteric viruses in treated wastewater and their potential release into the environment or use for agriculture are very critical matters in public health. In our study, PCR (polymerase chain reaction) analysis of enteric viruses was performed on 59 samples of influents and effluents collected from Tubli wastewater treatment plant (Water Pollution Control Center (WPCC)) and Tubli Bay, where the effluents were discharged, in Kingdom of Bahrain during two sampling periods. Four clinically essential waterborne enteric viruses were examined: enterovirus (EV), hepatitis A virus (HAV), astroviruses (AV), and rotaviruses (RV) and compared to standard bacterial and bacteriophages indicators of fecal pollution. Detection rates of EV, AV, HAV, and RV in the influent samples were 100%, 75%, 12.5%, and 12.5%, respectively, while 50% of the effluent samples from Tubli WPCC contained only EV RNA. None of the tested enteric viruses could be detected in any of the samples collected directly from Tubli Bay. Effluent samples from Tubli plant did not show significant seasonal differences. Since detection of enteric viruses genome does not necessarily indicate infectivity, the infectivity of these viruses was evaluated through isolation and growth of indictor bacteria and bacteriophages. High concentration of fecal bacteriological indicators was detected in all effluents samples (100%): 3.20 × 103 cfu/mL for E. coli, 1.32 × 103 cfu/mL for Salmonella spp., and 1.92 × 103 cfu/mL for Shigella spp. E. coli and Salmonella specific bacteriophages were also detected in the effluent samples in high titers. The combined results of PCR and bacterial enumeration point to a probable public health risk via the use of these wastewaters in agriculture or their discharge into the sea. Continuous surveillance of viral and bacterial prevalence and their resistance to sewage disinfection procedures could contribute to a better control of risks associated with the recycling of effluent wastewater and its release into the environment

Workplace bullying in surgical environments in Saudi Arabia: A multiregional cross-sectional study

BACKGROUND: Workplace bullying (WPB) is any sort of repeated and unjustified verbal, sexual, or physical intimidation that a person is exposed to by a group or another person in the workplace. In healthcare environments, practitioners are occasionally victims of WPB incidents. Bullying in surgical environments is an important issue that needs attention as it could affect patient care either directly or indirectly. The objective of this study was to assess the prevalence of bullying in surgical environments in multiple regions in Saudi Arabia. MATERIALS AND METHODS: This cross-sectional study was conducted among surgeons, trainees, interns, nurses, and students in surgical specialties in multiple Saudi regions. The survey was designed by Survey Monkey and posted online. The data were analyzed through SPSS Version-21 by computing descriptive statistics as frequency and percentages with graph construction. RESULTS: About two-thirds (65.2%) of the 788 study participants were male and were between the age of 20 and 29 years (67.8%). Consultants came first as perpetrators of bullying in the past 12 months (44.3%) and residents and interns were the major victims. The NAQ-R score ranged from 22.00 to 110.00, with a mean score of 42.47 (SD=17.9). Statistically significant association was found between mean NAQ-R score and age (P = 0.007), specialty (P = 0.002), and position (P < 0.001). CONCLUSION: WPB is a pervasive problem in surgical environments in multiple regions of Saudi Arabia. Consultants and specialists are the primary offenders in bullying, which makes the hospital an environment for bullying behaviors