97 research outputs found
Design and Development of a Microstrip Sensor for Measurement of Moisture Content in Rice Grains
A Microstrip moisture sensor is developed based on microwave attenuation and is used for measuring moisture content of rice grains. This sensor is suitable for a broad range of moisture content ranging from 0% to 40 % (wet basis). It was fabricated using RT-Duriod with dielectric properties of 2.2-j0.002 as the substrate, with operating frequency at 9.0 GHz. In this technique only the small part of sample is needed to contact with the microstrip line, therefore the measurement can be done with more accuracy and in a shorter time.
Theoretical analysis based on quasi-transverse electromagnetic mode (TEM mode) in four layered microstrip is carried out to evaluate design parameters such as microstrip characteristic impedance, effective dielectric constant, length and thickness due to the sensitivity of the sensor. The analysis of the complex electromagnetic waves in this system is presented using signal flow graphs and solved by Mason's non-touching loops rules. To this end Visual Fortran programs is written and documented to evaluate all the design parameters needed and to estimate the microstrip patterns.
In the other part of this study, investigation was made to find the relation between the dielectric properties and moisture content of rice grains. The dielectric mixture theory has been derived to solve the problem of non homogenous medium. In the purpose of verifying the mixture theory the theoretical results has been compared with the empirical results. It was found that the dielectric properties of dried rice samples were in the range of 1.20 to 1.88 for ε′ and 0.065 to 0.23 for ε″ and even can increased up to 30-j18 in maximum moisture content, respectively. A close and good agreement to theoretical expectation values is found. A computer program EMIX is written to predict the dielectric properties of wet basis rice grain by knowing the values of physical properties for dry basis.
In this study, analyzes of the sensor and various type of the rice grain samples with the effect of density and temperature of rice grains to the total attenuation of the sensor has been studied and the predicted results are compared with experimental results. The effect of air inside the medium and the compactness of the material under the test has been studied and the errors of ± 0.16 dB has been calculated for the measured reflected attenuation of the sensor.
The micrsotrip sensor was tested on five types of rice grains in the range of 1% to 40% moisture content. The sensor has predicted moisture contents with standard error of ±0.22 dB and accuracy of 1.5% MC wet basis compared to standard oven drying method. Moisture contents of rice grain samples were found in the range of 11 to 12.5% at room temperature (25°C).
A new proposed moisture sensor which can measure the moisture content of grains contained in a sack manner has been given. The slim and sharp geometry of the sensor enable it to measure the mean volumetric values of moisture content of rice since it penetrates deep into the sack. Therefore, this method can be so useful in industry for moisture content measurement of rice grains and even some other grains like wheat, corn barley and so on, to determine the proper time of harvest, safe storage and quality control of grains
Incidental detection of COVID-19 associated pneumonia by [99mTc]UBI scintigraphy
A 31-year-old woman who had multiple orthopedic surgeries on the left lower limb and recently suffered from pain and redness in the lateral left lower thigh was referred to the hospital to rule out osteomyelitis by [99mTc]UBI scintigraphy. Except soft tissue inflammation in the mentioned region, the scan showed significant and diffuse both lungs uptake incidentally. The patient had experienced symptoms of COVID-19 disease recently. Chest HRCT scan also revealed multiple segmental ground-glass opacities (GGOs) which were typical features for lung involvement of COVID-19 associated pneumonia
Incidental detection of COVID-19 associated pneumonia by thyroid scintigraphy
This report presents a case of a 49-year-old woman with complaint of sore throat and front neck pain, who referred to a hospital for thyroid scan due to suppressed TSH level (0.005 mU/L). Diffuse and bilateral lungs uptake in the scan was noticed incidentally. The patient had positive history of COVID-19 symptoms. Multifocal and bilateral ground-glass opacities (GGOs) in both lungs were compatible with typical features of lung involvement in COVID-19-associated pneumonia
Experimental and theoretical investigations of new Schiff base compound adsorption on aluminium in 1 M HCl
The new Schiff base, 2,2\u27-((1Z,1\u27Z)-(((propane-1,3-diylbis(oxy))bis(2,1-phenylene))bis(methanylylidene))bis(azanylylidene))diethanol, was investigated as a corrosion inhibitor of aluminium in 1 M HCl. Polarization and electrochemical impedance measurements were used for this purpose. Polarization curves showed that the compound is a mixed-type corrosion inhibitor. Also, the results showed an increase in inhibition efficiency as the concentration of the compound increased. The maximum corrosion inhibition efficiency of approximately 81 % was reached at the concentration of 2 mg/L of the inhibitor. The results of the density functional theory method were consistent with the experimental results. The surface morphology of the samples was examined under atomic force microscopy
The analysis and design of multi-layer microstrip moisture sensor for rice grain
The analysis and optimal design of a multi-layered microstrip sensor for measuring moisture content of ricegrain are described. The microstrip sensing structure consists of three layers: substrate, protective layer and semi-infinite grain medium. The effective dielectric constant, characteristic impedance and attenuation or insertion loss of this structure are calculated at various moisture contents with respect to the thickness of the protective layer thickness. The sensor is operated at 9 GHz and is suitable for a broad range of moisture contents (MC) ranging from 10% to 30% (wet basis). This study investigated the optimal thickness of the protective layer for suitable sensitivity, the thickness of grain medium which can be consider as semi-infinite thickness, the effect of kernel density and loading method. The experimental results for the attenuation of the signal at various moisture contents agree reasonably with the theoretical prediction however for better accuracy, the compactness of grain medium should be observed. The effect of air inside the medium and compactness of the material under the test has been studied and the errors of ±0.16 dB have been calculated for the measured reflected attenuation of the sensor. The overall accuracy of the sensor is about ±1.5% moisture content as compared to oven drying method
Instructional Strategies for Motivating and Engraining Generation Z Students in Their Own Learning Process
In the last few years, a number of significant research studies were conducted focusing on identifying and determining the root cause and also factors that critically contribute to students failure and success in higher education. These studies have enabled educators to evaluate the underlying causes by analyzing different perspectives presented by students, faculty and academic leaders. Various studies were conducted and published in the past that have addressed the same issue. For example, in three related studies conducted and presented at the Higher Learning Commission (HLC) conference in Chicago, Illinois, the surveyed participants (students, faculty, and academic leaders) provided concrete root-cause factors for student’s failure at college and university level. Student’s academic readiness, self-motivation, study habits, and students attitude towards education were the most mentioned root-causes by both, faculty and academic leaders (Appendix 1). During the studies, all participants agreed upon the fact that in order to succeed, students should have clear mindsets and should be aware of the reasons and requirements they will need to meet in order to enroll in a specific course. They should be thoroughly aware of their purpose for attending a school beyond just getting passing grades and a degree to get jobs. However, all three surveyed groups strongly believe that it is not only the student’s responsibility, but also the responsibility of instructors and college administration to keep students motivated after admitting them to their colleges, programs, and courses (Cherif, Movahedzadeh, Adams, Martyn 2013; 2014; 2015). In this paper, we explore the implementation of some proposed recommendations from various research studies for improving students learning and instructors teaching in a classroom setting. Keywords: Modern students, Motivations; Student academic performance and retention, Student success. DOI: 10.7176/JEP/10-3-0
Simulation
Background & Objective: Simulation is an educational technique which through providing whole or part of a clinical experience helps students to learn without being afraid of either their personal weaknesses or hurting the patient during interaction. Manipulation of medical education is widely being spread all over the world and this can be due to various factors such as technological improvements, ethical issues relating to practicing clinical skills, crowdedness of clinical environments for educational purposes, illness severity in most patients, drop in the length of patient’s stay in the hospitals, shortage of specialized staff in hospitals to facilitate educational process and so on.
Methods: The current study has reviewed existing books, library references, papers and essays available in different scientific databases using keywords of “simulation”, “medical education” and “clinical skills”.
Results: Simulation offers several advantages including increase in patient’s safety, reinforcement of interactive learning and student-centered, improvement in problem-solving abilities and critical thinking skills, and self-paced learning. Despite all the above-mentioned benefits, the point is that due to the high costs of simulation equipment as well as improper cost management policies particularly in educational centers, several studies should be run to analyze outcomes of manipulation of different simulators on students’ learning and then based on the efficiency of the simulators, the proper ones be used for educational purposes in clinical environments.
Keywords
Simulation Medical education Clinical skill
Accidental Children Poisoning With Methadone: An Iranian Pediatric Sectional Study
How to Cite This Article: Jabbehdari S, Farnaghi F, Shariatmadari SF, Jafari J, Mehregan FF, Karimzadeh P. Accidental Children Poisoning With Methadone: An Iranian Pediatric Sectional Study. Iran J Child Neurol. 2013 Autumn;7(7): 32-34.ObjectiveToxic poisoning with methadone is common in children in Iran. Our study was carried out due to the changing pattern of methadone poisoning in recent years and increasing methadone toxicity. Materials & MethodsIn this descriptive-sectional study, all of the methadone poisoned children younger than 12 years who were admitted to the Loghman Hakim Hospital in 2012, were assessed. Clinical symptoms and signs, para-clinical findings, and treatment were evaluated. ResultsIn this study, 16 boys and 15 girls who had been poisoned by methadone were enrolled. The mean age of patients was 55 months. All patients had been poisoned randomly or due to parent’s mistakes. The mean time of symptoms onset after methadone consumption was 1 hour and 30 Min, indicating a relatively long time after onset of symptoms.Clinical findings were drowsiness (75%), miotic pupil (68 %), vomiting (61%), rapid shallow breathing (57%) and apnea (40%). In paraclinical tests, respiratory acidosis (69%) and leukocytosis (55.2%) were seen. The most important finding was increase in distance of QT in ECG (23.8%). The mean time of treatment with naloxone infusion was 51 hours. Three percent of patients had a return of symptoms after discontinuation of methadone. In patients with apnea, a longer course of treatment was required, and this difference was significant. Also, 17% of patients with apnea had aspiration pneumonia, which was statistically significant. ConclusionWe suggest long time treatment with naloxone and considering the probability of return of symptoms after discontinuation of methadone.ReferencesGoldfrank L, Flomenbaum N, Lewin N. Goldfrank’s Toxicologic Emergencies. 7th ed. McGraw–Hill 2002; p. 590-607.Schelble DT. Phosgene and phosphine. In: Haddad LM, Shannon MW, Winchester J, eds. Clinical Management of Poisoning and Drug Overdose. 3rd ed. Philadelphia: WB Saunders; 2007. p. 640-7.Jennifer C, Gibson A. Accidental methadone poisoning in children: A call for Canadian research action. Child Abuse Negl;2010;34(8):553-4.Binchy JM, Molyneux E, Manning J. Accidental ingestion of methadone by children in Merseyside. BMJ 1994;308(6940:1335-6.Zamani N, Sanaei-Zadeh H, Mostafazadeh B. Hallmarks of opium poisoning in infants and toddlers. Trop Doct 2010;40(4):220-2.LoVecchio F, Pizon A, Riley B, Sami A, D’Incognito C. Onset of symptoms after methadone overdose. Am J Emerg Med 2007;25(1):57-9.Thanavaro KL, Thanavaro JL. Methadone-induced torsades de pointes: a twist of fate. Heart Lung 2011;40(5):448-53.Gaalen FA, Compier EA, Fogteloo AJ. Sudden hearing loss after a methadone overdose. Eur Arch Otorhinolaryngol 2009;266(5):773-4.Lynch RE, Hack RA. Methadone-induced rigid-chest syndrome after substantial overdose.Pediatrics. 2010; 126(1):232-4.Sidlo J, Valuch J, Ocko P, Bauerová J. Fatal methadone intoxication in a 11-month-old male infant. Soud Lek 2009;54(2):23-5.
Metastatic triple negative breast cancer adapts its metabolism to destination tissues while retaining key metabolic signatures
Triple negative breast cancer (TNBC) metastases are assumed to exhibit similar functions in different organs as in the original primary tumor. However, studies of metastasis are often limited to a comparison of metastatic tumors with primary tumors of their origin, and little is known about the adaptation to the local environment of the metastatic sites. We therefore used transcriptomic data and metabolic network analyses to investigate whether metastatic tumors adapt their metabolism to the metastatic site and found that metastatic tumors adopt a metabolic signature with some similarity to primary tumors of their destinations. The extent of adaptation, however, varies across different organs, and metastatic tumors retain metabolic signatures associated with TNBC. Our findings suggest that a combination of anti-metastatic approaches and metabolic inhibitors selected specifically for different metastatic sites, rather than solely targeting TNBC primary tumors, may constitute a more effective treatment approach
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