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1.
Ann Med Surg (Lond) ; 86(3): 1352-1358, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38463116

ABSTRACT

Background: The role of metacognition as a common concept in education is undeniable. One of the challenges in the field of metacognition is to measure the impact of metacognition in teaching with practical tools. Therefore, this study aimed to investigate the psychometric characteristics of the metacognition questionnaire in teaching. Methods: In this cross-sectional study, the statistical population of the study included all teachers in 2020 which was selected by an available sampling method of 137 people. The data were collected using a teacher's metacognition questionnaire (TMI). A Confirmatory, Pearson correlation coefficient was used to analyze the data. For this purpose, the use of SPSS-25 and LISREL software has been used. Results: of exploratory and confirmatory factor analysis indicate that. The validity and retest of the total score were calculated to be 0.93 and 0.86, respectively. The credibility of its subscales was also acceptable. Conclusion: As a result, it can be stated that the questionnaire has the proper psychometric properties for use in Iranian society and can be used as a valid tool for identifying teachers with teaching problems and teaching methods.

2.
J Med Radiat Sci ; 71(2): 251-260, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38454637

ABSTRACT

INTRODUCTION: Concerns regarding the adverse consequences of radiation have increased due to the expanded application of computed tomography (CT) in medical practice. Certain studies have indicated that the radiation dosage depends on the anatomical region, the imaging technique employed and patient-specific variables. The aim of this study is to present fitting models for the estimation of age-specific dose estimates (ASDE), in the same direction of size-specific dose estimates, and effective doses based on patient age, gender and the type of CT examination used in paediatric head, chest and abdomen-pelvis imaging. METHODS: A total of 583 paediatric patients were included in the study. Radiometric data were gathered from DICOM files. The patients were categorised into five distinct groups (under 15 years of age), and the effective dose, organ dose and ASDE were computed for the CT examinations involving the head, chest and abdomen-pelvis. Finally, the best fitting models were presented for estimation of ASDE and effective doses based on patient age, gender and the type of examination. RESULTS: The ASDE in head, chest, and abdomen-pelvis CT examinations increases with increasing age. As age increases, the effective dose in head and abdomen-pelvis CT scans decreased. However, for chest scans, the effective dose initially showed a decreasing trend until the first year of life; after that, it increases in correlation with age. CONCLUSIONS: Based on the presented fitting model for the ASDE, these CT scan quantities depend on factors such as patient age and the type of CT examination. For the effective dose, the gender was also included in the fitting model. By utilising the information about the scan type, region and age, it becomes feasible to estimate the ASDE and effective dose using the models provided in this study.


Subject(s)
Head , Radiation Dosage , Tomography, X-Ray Computed , Humans , Child , Female , Male , Adolescent , Child, Preschool , Infant , Head/diagnostic imaging , Pelvis/diagnostic imaging , Abdomen/diagnostic imaging , Thorax/diagnostic imaging , Age Factors , Infant, Newborn , Radiography, Thoracic , Radiography, Abdominal/methods
3.
J Sci Food Agric ; 103(6): 2715-2726, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36066551

ABSTRACT

In this study, the impacts of small-scale farmers on food security enhancement were estimated in three dimensions of food availability, food access and food utilization. In the current study, a systematic review and meta-analysis have been performed to synthesize results from 75 original articles. It includes the pooling of data that quantitatively investigate whether or not causal links characterized in the original articles remain valid across a broader scope of the literature. The findings show that farmers who are small-scale in natural/physical capital would lead to higher median food production and agricultural productivity, compared with small-scale farmers in financial capital, at about 19% and 15%, respectively. Meta-regression results indicate that small-scale farmers in natural/physical capital have significantly positive effects on the average agricultural productivity, food income and biofortification. By contrast, farmers who are small-scale in financial capital have negative effects on food security. The influential role of these small-scale farmers should also be considered since food insecurity leads to socio-economic implications. Therefore, it is recommended to cultivate higher value crops, to participate in various income-generating activities such as fisheries and forestry, and to pay agricultural credits. The effect of the size of small-scale farmers on global food security is very useful for policymakers to plan for a world without hunger. © 2022 Society of Chemical Industry.


Subject(s)
Farmers , Food Supply , Humans , Agriculture/methods , Income , Food Security
4.
Eng Life Sci ; 22(8): 519-534, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35936072

ABSTRACT

Due to their high sensitivity, simplicity, portability, self-contained, and low cost, the development of electrochemical biosensors is a beneficial way to diagnose and anticipate many types of cancers. An electrochemical nanocomposite-based aptasensor is fabricated for the determination of miRNA-128 concentration as the acute lymphoblastic leukemia (ALL) biomarker for the first time. The aptamer chains were immobilized on the surface of the glassy carbon electrode (GCE) through gold nanoparticles/magnetite/reduced graphene oxide (AuNPs/Fe3O4/RGO). Fast Fourier transform infrared (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM) were used to characterize synthesized nanomaterials. Cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS) were used to characterize the modified GCE in both label-free and labeled methods. The results indicate that the modified working electrode has high selectivity and for miRNA-128 over other biomolecules. The hexacyanoferrate redox system typically operated at around 0.3 V (vs. Ag/AgCl), and the methylene blue redox system ran at about 0 V, were used as an electrochemical probe. The detection limit and linear detection range for hexacyanoferrate and methylene blue are 0.05346 fM, 0.1-0.9 fM, and 0.005483 fM, 0.01-0.09 fM, respectively. The stability and diffusion control analyses were performed as well. In both label-free and labeled methods, the modified electron showed high selectivity for miRNA-128. The use of methylene blue as a safer redox mediator caused miRNA-128 to be detected with greater accuracy at low potentials in PBS media. The findings also show the substantial improvement in detection limit and linearity by using reduced graphene oxide-magnetite-gold nanoparticles that can be verified by comparing with previous studies on the detection of other miRNAs.

6.
Molecules ; 26(5)2021 03 05.
Article in English | MEDLINE | ID: mdl-33807597

ABSTRACT

Efforts to develop the necessary biotechnologies in Greater Celandine (Chelidonium majus L.), a leading plant resource for the development of plant-derived medicines, have been hampered by the lack of knowledge about transcriptome and metabolome regulations of its medicinal components. Therefore, this study aimed to examine the effect of abiotic elicitors, methyl jasmonate (MJ) and salicylic acid (SA), at different time courses (12, 24, 48, and 72 h), on expression and metabolome of key benzophenanthridine alkaloids (BPAs) in an optimized in vitro culture. Gene expression analysis indicated the upregulation of CFS (cheilanthifoline synthase) to 2.62, 4.85, and 7.28 times higher than the control at 12, 24, and 48 h respectively, under MJ elicitation. Besides, MJ upregulated the expression of TNMT (tetrahydroprotoberberine N-methyltransferase) to 2.79, 4.75, and 7.21 times at 12, 24, and 48 h respectively, compared to the control. Investigation of BPAs revealed a significant enhancement in the chelidonine content (9.86 µg/mg) after 72 h of MJ elicitation. Additionally, sanguinarine content increased to its highest level (3.42 µg/mg) after 24 h of MJ elicitation; however, no significant enhancement was detected in its content in shorter elicitation time courses. Generally, higher gene expression and BPAs' level was observed through longer elicitation courses (48 and 72 h). Our findings take part in improving the understanding of transcription and metabolic regulation of BPAs in cultured Greater Celandine cells.


Subject(s)
Acetates/pharmacology , Benzophenanthridines/metabolism , Cell Culture Techniques/methods , Chelidonium/metabolism , Cyclopentanes/pharmacology , Oxylipins/pharmacology , Salicylic Acid/pharmacology , Chelidonium/cytology , Chelidonium/drug effects , Chelidonium/genetics , Enzymes/genetics , Enzymes/metabolism , Gene Expression Regulation, Plant/drug effects , Plant Cells/drug effects , Plant Cells/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Medicinal/cytology , Plants, Medicinal/drug effects , Plants, Medicinal/metabolism
7.
Health Phys ; 118(1): 65-74, 2020 01.
Article in English | MEDLINE | ID: mdl-31764421

ABSTRACT

Medical linear accelerators (linacs) are the most frequently applied radiation therapy machines in the locoregional treatment of cancers by producing either high-energy electron or photon beams. However, with high-energy photons (>8 MeV), interaction of these photons with different high-Z nuclei of materials in components of the linac head unavoidably generates neutrons. On the other hand, the average energy of these generated neutrons has almost the highest radiation-weighting factor. Therefore, the produced neutrons should not be neglected. There are various tools for the measurement of neutron dose/fluence generated in a megavoltage linac, including thermoluminescent dosimeters, solid-state nuclear track detectors, bubble detectors, activation foils, Bonner sphere systems, and ionization chamber pairs. In this review article, each of the above-mentioned dosimetric methods will be described in detail.


Subject(s)
Neoplasms/radiotherapy , Neutrons , Particle Accelerators/instrumentation , Radiation Monitoring/methods , Radiometry/methods , Humans , Radiotherapy Dosage
8.
J Cancer Res Ther ; 15(3): 491-497, 2019.
Article in English | MEDLINE | ID: mdl-31169209

ABSTRACT

AIM: The main purpose of this study is to evaluate the effect of dose perturbation due to common dental restoration materials in the head and neck radiotherapy with a 15 MV external photon beam. SETTING AND DESIGN: Teeth with three dental restorations such as tooth filled with Amalgam, Ni-Cr alloy, and Ceramco were simulated by MCNPX Monte Carlo code. In this simulation, the dental materials were exposed by a 15 MV photon beam from a Siemens Primus linac, inside a water phantom. MATERIALS AND METHODS: A Siemens Primus linear accelerator and a phantom including: tooth only, tooth with Amalgam, tooth with Ni-Cr alloy, and tooth with Ceramco were simulated by MCNPX Monte Carlo code, separately. The percentage dose change was evaluated relative to dose in water versus depth for these samples on the beam's central axis. The absolute dose by prescription of 100 cGy dose in water phantom at 3.0 cm depth was calculated for water, tooth, tooth with Amalgam, tooth with Ni-Cr alloy, and tooth with Ceramco. RESULTS: The maximum percentage dose change is related to tooth with Ni-Cr alloy, tooth, tooth with Ceramco, and tooth with Amalgam with amounts of 7.73%, 6.95%, 4.7%, and 3.06% relative to water at 0.75 cm depth, respectively. When 100.0 cGy dose was prescribed at 3.1 cm, the maximum absolute dose was 201.0% in the presence of tooth with Ni-Cr alloy at 0.75 cm. CONCLUSION: Introduction of the compositions of dental restorations can improve the accuracy of dosimetric calculations in treatment planning and protect the healthy tissues surrounding teeth from a considerable overdose.


Subject(s)
Dental Restoration Repair , Monte Carlo Method , Radiotherapy Dosage , Radiotherapy/adverse effects , Dental Alloys , Dental Porcelain , Humans
9.
Thrombosis ; 2011: 785459, 2011.
Article in English | MEDLINE | ID: mdl-22242201

ABSTRACT

Aim. This study was designed to examine the possible role of high-dose intravenous methylprednisolone (IVMP) in the development of venous thrombosis (VT). The cerebral one anecdotally had been reported in patients with relapsing remitting multiple sclerosis (RRMS) in acute attacks and the possible preventive role of enoxaparin. Material and Methods. From a pool of 520 patients, 388 patients with definite RRMS who fulfilled entry characteristics were selected and randomly received either a 5-day course of daily 1 gr IVMP or the aforementioned plus 5 days of daily subcutaneous 40 units of enoxaparin according to a predefined protocol. Results. Mean age, gender ratio, mean relapse rate, and EDSS were similar in both groups of patients (P > 0.05). Finally, 366 patients remained in the study. Of 188 patients treated with IVMP with 855 relapses, 5 developed VT (0.37% per patient per year and 0.58% per each course of IVMP) within 3 to 15 days of starting therapy. None of the 178 patients who experienced 809 relapses who received IVMP plus enoxaparin developed such complications. Conclusion. The study implies that high-dose IVMP in MS exacerbation may increase the risk of VT and prophylactic anticoagulant treatment in this setting is warranted.

10.
J Neurol Sci ; 276(1-2): 130-2, 2009 Jan 15.
Article in English | MEDLINE | ID: mdl-18962726

ABSTRACT

Clinical course, magnetic resonance imaging (MRI) findings and cerebrospinal fluid data (CSF) on 20 patients among 520 with clinically definite multiple sclerosis (MS) according to the criteria of Poser et al., with opticospinal clinical presentation above 5 years and mean disease duration of 8+/-4.4 years were reviewed. The prevalence rate was 3.8%. The clinical course was relapsing-remitting (RR) for all patients. The mean age of onset was 24+/-8.2 years. The gender ratio was 2.3:1 female:male. First clinical presentation was spinal signs in 12 (60%), optic neuritis in 7 (35%) and simultaneous involvement of both eyes in 1 (5%) patient. No transverse myelitis (TM), sustained severe optic neuritis (SSON) or minor brain stem signs were recorded. No conversion to conventional MS (CMS) or secondary progressive MS (SPMS) was identified during the study period and no case had positive family history for the disease. The yearly number of attacks was 0.66+/-0.84, with mean Kurtzke expanded disability status scale (EDSS) of 2.5+/-1.2. All patients had 1 to 5 hemispheral T2 lesions in brain MRI, non-fulfilled Barkhof criteria for brain lesions. All had preventricular and 14 (70%) had juxtacortical lesions. None had gadolinium T1 enhanced lesions. No involvement of the brainstem or cerebellar structures was detected. Fifteen had 1 cervical lesion, five had 2 and four had 1 concomitant thoracic cord signal, all extending below three vertebral segments in sagittal planes with peripheral white matter location on the axial planes. Spinal fluid contained normal cell and protein with negative oligoclonal bands (OB).


Subject(s)
Multiple Sclerosis, Relapsing-Remitting/complications , Optic Neuritis/etiology , Spinal Cord/pathology , Age of Onset , Disability Evaluation , Female , Humans , Iran/epidemiology , Magnetic Resonance Imaging/methods , Male , Multiple Sclerosis, Relapsing-Remitting/cerebrospinal fluid , Multiple Sclerosis, Relapsing-Remitting/epidemiology , Optic Neuritis/pathology , Retrospective Studies
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