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Despite recent calls to engage in scholarship with attention to anti-racism, equity, and social justice at a global level in Health Professions Education (HPE), the field has made few significant advances in incorporating the views of the so-called "Other" in understanding the nature, origin, and scope of knowledge as well as the epistemic justification of knowledge production. Editors, authors, and reviewers must take responsibility for questioning existing systems and structures, specifically about how they diffuse the knowledge of a few and silence the knowledge of many. This article presents 12 recommendations proposed by The Global South Counterspace Authors Collective (GSCAC), a group of HPE professionals, representing countries in the Global South, to help the Global North enact practical changes to become more inclusive and engage in authentic and representative work in HPE publishing. This list is not all-encompassing but a first step to begin rectifying non-inclusive structures in our field.
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BACKGROUND: Artificial intelligence (AI) has affected our day-to-day in a great extent. Healthcare industry is one of the mainstream fields among those and produced a noticeable change in treatment and education. Medical students must comprehend well why AI technologies mediate and frame their decisions on medical issues. Formalizing of instruction on AI concepts can facilitate learners to grasp AI outcomes in association with their sensory perceptions and thinking in the dynamic and ambiguous reality of daily medical practice. The purpose of this study is to provide consensus on the competencies required by medical graduates to be ready for artificial intelligence technologies and possible applications in medicine and reporting the results. MATERIALS AND METHODS: A three-round e-Delphi survey was conducted between February 2020 and November 2020. The Delphi panel accorporated experts from different backgrounds; (i) healthcare professionals/ academicians; (ii) computer and data science professionals/ academics; (iii) law and ethics professionals/ academics; and (iv) medical students. Round 1 in the Delphi survey began with exploratory open-ended questions. Responses received in the first round evaluated and refined to a 27-item questionnaire which then sent to the experts to be rated using a 7-point Likert type scale (1: Strongly Disagree-7: Strongly Agree). Similar to the second round, the participants repeated their assessments in the third round by using the second-round analysis. The agreement level and strength of the consensus was decided based on third phase results. Median scores was used to calculate the agreement level and the interquartile range (IQR) was used for determining the strength of the consensus. RESULTS: Among 128 invitees, a total of 94 agreed to become members of the expert panel. Of them 75 (79.8%) completed the Round 1 questionnaire, 69/75 (92.0%) completed the Round 2 and 60/69 (87.0%) responded to the Round 3. There was a strong agreement on the 23 items and weak agreement on the 4 items. CONCLUSIONS: This study has provided a consensus list of the competencies required by the medical graduates to be ready for AI implications that would bring new perspectives to medical education curricula. The unique feature of the current research is providing a guiding role in integrating AI into curriculum processes, syllabus content and training of medical students.
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Artificial Intelligence , Education, Medical , Consensus , Curriculum , Delphi Technique , HumansABSTRACT
BACKGROUND: The aim of the study is to analyse the demographic and anatomical details of the Huschke's foramen (HF) which have not been previously studied and to present a new clinical perspective. MATERIALS AND METHODS: Multidetector computed tomography (MDCT) images of 495 patients were retrospectively evaluated. Presence of a HF, its' size, relations to side, age and gender were noted for every patient. Size of the foramen was measured in the axial plane, as well as on the reconstructed coronal and sagittal planes. RESULTS: Of the 495 patients 99 (20%) had HF. There was no significant difference between females and males according to the presence of the HF and the side of the HF. When the dimension of the left- and the right-sided HFs were compared, there were no significant differences on none of the axes for the patients with unilateral or bilateral HF. There was no significant linear correlation between age and the dimension in the axial axis, the dimension in the sagittal axis and the dimension in the coronal axis CONCLUSIONS: The present work presenting morphologic and statistical variables of HF provides data for further studies which will indicate risk factors of herniation through HF. By the aid of MDCT, which is sensitive method for detection of the HF because of its thin sections, high spatial resolution, and multiplanar capabilities, lesions which were previously diagnosed as dehiscence were found to be defects.
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Multidetector Computed Tomography , Female , Humans , Male , Retrospective StudiesABSTRACT
BACKGROUND: It is unlikely that applications of artificial intelligence (AI) will completely replace physicians. However, it is very likely that AI applications will acquire many of their roles and generate new tasks in medical care. To be ready for new roles and tasks, medical students and physicians will need to understand the fundamentals of AI and data science, mathematical concepts, and related ethical and medico-legal issues in addition with the standard medical principles. Nevertheless, there is no valid and reliable instrument available in the literature to measure medical AI readiness. In this study, we have described the development of a valid and reliable psychometric measurement tool for the assessment of the perceived readiness of medical students on AI technologies and its applications in medicine. METHODS: To define medical students' required competencies on AI, a diverse set of experts' opinions were obtained by a qualitative method and were used as a theoretical framework, while creating the item pool of the scale. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were applied. RESULTS: A total of 568 medical students during the EFA phase and 329 medical students during the CFA phase, enrolled in two different public universities in Turkey participated in this study. The initial 27-items finalized with a 22-items scale in a four-factor structure (cognition, ability, vision, and ethics), which explains 50.9% cumulative variance that resulted from the EFA. Cronbach's alpha reliability coefficient was 0.87. CFA indicated appropriate fit of the four-factor model (χ2/df = 3.81, RMSEA = 0.094, SRMR = 0.057, CFI = 0.938, and NNFI (TLI) = 0.928). These values showed that the four-factor model has construct validity. CONCLUSIONS: The newly developed Medical Artificial Intelligence Readiness Scale for Medical Students (MAIRS-MS) was found to be valid and reliable tool for evaluation and monitoring of perceived readiness levels of medical students on AI technologies and applications. Medical schools may follow 'a physician training perspective that is compatible with AI in medicine' to their curricula by using MAIRS-MS. This scale could be benefitted by medical and health science education institutions as a valuable curriculum development tool with its learner needs assessment and participants' end-course perceived readiness opportunities.
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Students, Medical , Artificial Intelligence , Humans , Psychometrics , Reproducibility of Results , Surveys and Questionnaires , TurkeyABSTRACT
BACKGROUND: Combination of hydroxychloroquine and azithromycin for the treatment of coronavirus disease 2019 (COVID-19) carries increased risk of corrected QT (QTc) prolongation and cardiac arrhythmias. OBJECTIVE: To characterize the ventricular repolarization indexes which are associated with malignant ventricular arrhythmias in patients treated with hydroxychloroquine and concomitant azithromycin for COVID-19. METHOD: A total of 81 patients who had hydroxychloroquine and azithromycin combination therapy because of possible or reverse-transcription polymertase chain reaction (RT-PCR) confirmed diagnosis of COVID-19 were included in the study. Baseline and control electrocardiograms (before and after treatment) were analyzed retrospectively. Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, which are ventricular repolarization indexes, were calculated. RESULTS: While there was no significant increase in QTc interval in patients receiving combination therapy, there was a significant increase in ventricular repolarization indexes. CONCLUSION: The increase in ventricular replarization indexes is associated with the risk of arrhythmia. In patients using QTc prolonging medication for COVID-19 treatment, QTc monitoring alone may not be sufficient to follow-up for arrhythmia. Even if there is no prolongation in QTc, an increase in ventricular repolarization indexes may be seen (Tab. 5, Ref. 37).
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Azithromycin/adverse effects , Coronavirus Infections/drug therapy , Hydroxychloroquine/adverse effects , Long QT Syndrome/chemically induced , Pneumonia, Viral/drug therapy , Betacoronavirus , COVID-19 , Drug Therapy, Combination , Electrocardiography , Humans , Pandemics , Retrospective Studies , SARS-CoV-2 , COVID-19 Drug TreatmentABSTRACT
Chronic obstructive pulmonary disease (COPD) is one of the causes of mortality worldwide with an increasing prevalence. Heart rate variability (HRV) reflects the regulation mechanism of the cardiac activity by the autonomic nervous system. The assessment of HRV by using nonlinear methods is more sensitive for the detection of complexity when compared to linear methods. This study aims to get information about the autonomic dysfunction occurred in patients with COPD by analysing the complexity of HRV. Electrocardiogram signals recorded from healthy subjects, patients with moderate COPD and severe COPD (eight subjects per group) were analysed. The HRV signals were acquired from ECG signals. Signals were reconstructed in the phase space and largest Lyapunov exponent (LLE), correlation dimension, Hurst exponent and approximate entropy (ApEn) values were calculated. It has seen that for the patients with COPD LLE, correlation dimension, Hurst exponent and ApEn values were less than control group. According to this, HRV complexity decreases in the presence of COPD. However, there is no significant difference between COPD groups and the severity of COPD has no effect on the chaoticity of the system. The results revealed that autonomic dysfunction occurred in patients with COPD is associated with reduced HRV complexity.
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Electrocardiography/statistics & numerical data , Heart Rate , Nonlinear Dynamics , Pulmonary Disease, Chronic Obstructive/physiopathology , Aged , Healthy Volunteers , Humans , Male , Middle AgedABSTRACT
BACKGROUND: As far as our literature searches showed us, morphological characteristics of cranium such as sutures, sutural bones and fontanelles had been examined in the skulls in the museums and dry specimens until now. As a modern method, three-dimensional virtual reconstruction of cranial bones by using multidetector computed tomography-computed tomography angiography (MDCT-CTA) can display in vivo morphological characteristics. In our study, we aimed to determine the presence and incidence of these morphological characteristics that can be clinically significant in our population, by using radiologic methods. MATERIALS AND METHODS: We examined head and neck regions of 185 patients via MDCT-CTA. We evaluated radiologically detectable variations of the metopic sutures, lambda, bregma, asterion and pterion, which can be very easily confused with fractures. Additionally, the differences between the genders and incidence of coexistence of these variations were evaluated. RESULTS: According to our study, the incidence of persistent metopic suture was 8.1% and the incidence of lambda variations was 5.9%. Variations were most commonly encountered on the left asterion, and least commonly on the bregma and left pterion. In the evaluation of the coexistence of the parameters and combinations, the Wormian bones located at the right and left asterions were detected. There were no statistically significant differences between genders. CONCLUSIONS: Variations of the sutures and sutural bones can be easily misdiagnosed with the fractures of related bony regions in unconscious patients with multiple traumas. During surgical interventions in these patients, surgeons must take this fact into consideration in order to make differential diagnosis of fractures and intersutural bone variations.
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Anatomic Variation , Bone and Bones/anatomy & histology , Bone and Bones/diagnostic imaging , Cranial Sutures/anatomy & histology , Cranial Sutures/diagnostic imaging , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
Objectives This paper aims to assess in a retrospective fashion the clinical and laboratory features, severity and outcome of juvenile systemic lupus erythematosus (jSLE) from a referral center in Turkey. Methods We have included all jSLE patients ( n = 92) diagnosed according to the revised American College of Rheumatology 1997 criteria between January 2004 and January 2017. Results The most prevalent clinical feature in our cohort was mucocutaneous manifestations (97.8%), followed by constitutional (81.5%), hematological (59.8%) and musculoskeletal manifestations (56.5%). Renal involvement was observed in 38% ( n = 35) of the patients, whereas biopsy-proven lupus nephritis was detected in 29.3% ( n = 27) of the cohort. Neurologic involvement was seen in 15 (16.3%) individuals. Among the patients positive for anticardiolipin IgM and/or IgG ( n = 11, 12%), only three developed antiphospholipid antibody syndrome. The mean SLEDAI-2K scores at disease onset (10.5 ± 4.8) showed a substantial decrease at last visit (4.3 ± 4.6). One-quarter of the patients (26.1%, n = 24) had damage according to the PedSDI criteria with a mean score of 0.45 ± 1.0 (range 0-7). When the PedSDI damage items were evaluated individually, growth failure was the most frequent damage criterion ( n = 6), followed by seizure ( n = 5). Two patients died during the designated study period of end-stage renal disease. The five-year and 10-year survival rate of our cohort was 100% and 94.4%, respectively. Conclusions Given the lower frequency of nephritis and central nervous system disease and lower basal disease activity and damage scores, we could conclude that children with jSLE in Turkey have a more favorable course compared to Asian and African American children, as expected from Caucasian ethnicity.
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Disease Progression , Kidney/pathology , Lupus Erythematosus, Systemic/mortality , Lupus Erythematosus, Systemic/physiopathology , Adolescent , Age of Onset , Central Nervous System Diseases/epidemiology , Child , Child, Preschool , Female , Humans , Kidney Failure, Chronic/mortality , Longitudinal Studies , Male , Retrospective Studies , Severity of Illness Index , Survival Rate , Turkey/epidemiology , Young AdultABSTRACT
OBJECTIVE: Understanding potential problems associated with primary double teeth (PDT) are important to provide prophylactic measures, thereby preventing or minimizing possible complications. The purposes of this study were to investigate the prevalence of PDT in a group of Turkish children and to compare the distribution of the different types of double primary teeth and their relationship to permanent successors. MATERIALS AND METHODS: A total of 17,268 children underwent a clinical examination to determine the presence of PDT. One hundred fifty-two PDT of 128 children were included in this study. All the 128 children with PDT underwent a clinical examination and had photographs taken at the time of the examination. The children underwent a further periapical or panoramic radiographic examination to determine the status of the underlying permanent successors. The PDT was classified according to Aguilo's classification. RESULTS: The prevalence of PDT was 0.74%, with no significant statistical difference between the sexes. PDT was most frequently observed between the mandibular lateral incisors and canines. Of the 152 PDT, 10.7% were Type I, 15.3% were Type II, 26.1% were Type III, and 47.9% were Type IV. Dental anomalies on the succedaneous permanent teeth were diagnosed in 69.4% of the children with affected primary dentition. Aplasia of the permanent lateral incisor was observed most frequently in association with Type I (52.7%) PDT. Caries involvement was observed most frequently in Type III (56.2%) PDT. CONCLUSION: The findings of this study have clinical relevance for the diagnosis of children with PDT. Early clinical and radiographic identification of PDT can help the clinician to evaluate the number and condition of permanent successors and draw up a proper treatment plan.
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Fused Teeth/epidemiology , Radiography, Panoramic , Tooth Abnormalities/epidemiology , Tooth, Deciduous/abnormalities , Tooth, Supernumerary/epidemiology , Child , Dental Caries/complications , Dental Caries/epidemiology , Dentition, Permanent , Female , Fused Teeth/diagnostic imaging , Humans , Incisor/abnormalities , Male , Physical Examination , Prevalence , Sexual Behavior , Tooth Abnormalities/diagnostic imaging , Tooth, Deciduous/diagnostic imaging , Turkey/epidemiologyABSTRACT
OBJECTIVE: We evaluated the patients who are candidates for active surveillance and treated with radical prostatectomy. These patients were compared with other patients who had not met the criteria of active surveillance. METHODS: In total, 135 patients were included in the study. The patients were divided into two groups. The patients in Group 1 had less than three positive cores, Gleason 6 (3 + 3) and PSA level equal to or less than 10 ng/ml. Patients in Group 2 had three or more positive cores, Gleason 6 (3 + 3) and PSA level equal to or higher than 10 ng/ml. Pathological results of each groups were compared. RESULTS: The patients' ages were between 52 and 76, and 50 and 77 in groups 1 and 2, retrospectively. There were 69 and 66 patients in groups 1 and 2, retrospectively. The mean age of patients, PSA levels, PSA density, and prostate volumes were 63.89 ± 5.89 years, 5.82 ± 1.84 ng/ml, 0.14 ± 0.07 and 51.21 ± 31.75 cc (Group 1) and 65.77 ± 6.36 years, 13.65 ± 17.11 ng/ml, 0.63 ± 1.03 and 45.44 ± 26.77 cc (Group 2). T2a, T2c, T3a and T3b were reported in 28 patients, 36 patients, 3 patients and 2 patients after pathological evaluation in Group 1,respectively. T2a, T2c, T3a and T3b were reported in 13 patients, 47 patients, 5 patients and 1 patient in the other group, respectively. CONCLUSION: The final pathology showed that there is no difference in the positive surgical margin, proportion of insignificant prostate cancer and Gleason upgrading between groups. The clinicians must be aware of the fact that active surveillance can be misdiagnosed in some patients (Tab. 2, Ref. 20).
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Population Surveillance , Prostate-Specific Antigen/blood , Prostatectomy , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Aged , Humans , Male , Middle Aged , Neoplasm Grading , Organ Size , Prostate/pathology , Prostatic Neoplasms/mortality , Retrospective Studies , Survival Analysis , Treatment OutcomeABSTRACT
OBJECTIVE: It has been suggested that electromagnetic radiation (EMR) by wireless devices (2.45 GHz) induces testicular apoptosis. We investigated if supplemental selenium (Se) and L-carnitine may reduce this adverse effect. MATERIAL: Twelve-week old male Wistar albino rats were used in this study. Twenty-four rats were equally divided into four groups which were named as: sham group, EMR-only, EMR+L-carnitine (1.5 mg L-carnitine/kg/day) and EMR+Se (1.5 mg Se/kg/-every other day). RESULTS: The level of Bcl-2, Bax, caspase-3 and -8 were compared and a significant difference was found between the sham and EMR-only groups (p < 0.05), and Bcl-2, Bax, caspase-3 and -8 expressions increased in the EMR-only group. The level of Bcl-2, Bax, tumour necrosis factor-alpha (TNF-α), caspase-3 and -8 were compared and a significant difference was found between the sham and EMR+L-carnitine groups (p < 0.05) and Bcl-2, Bax, TNF-α, caspase-3 and -8 expressions increased in the EMR+L-carnitine group. The level of Bcl-2, Bax, TNF-α, caspase-3 and -8 were compared and a significant difference was found between the sham and EMR+Se groups (p < 0.05) and Bcl-2, Bax, TNF-α, caspase-3 and -8 expressions increased in the EMR+Se group. When the expression of caspase-8 was compared, a significant difference was found between the EMR-only and EMR+Se groups (p < 0.05). Caspase-8 expression decreased in EMR+Se group compared with EMR-only group. CONCLUSION: Electromagnetic radiation exposure resulted in testicular apoptosis in rats, mainly by the intrinsic pathways by down-regulated expression of caspase-8. Reduction in the activation of the intrinsic pathway of apoptosis was found higher with selenium administration compared with L-carnitine administration.
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OBJECTIVE: The study was aimed at introducing the modified version of the organ transplantation coordinator course including simulated donor family encounters (SDFEs), communication skills, and evaluating the participants' opinions, achievement levels, and how they implemented what they learned in the course in their work settings. METHODS: The course was modified using the ADDIE (analysis, design, development, implementation, and evaluation) model and was evaluated in three steps: The participants' views were obtained using the course overall evaluation form and communication skills evaluation form, their success was assessed with the post-test and SDFEs evaluation form, and the effects of what they learned during the course on their work settings were assessed through phone interviews. At this step, the participants were asked to write letters about the targets they intended to achieve in their work settings. The letters were analyzed with the content analysis method, and a questionnaire consisting of 105 targets was developed. A year later the participants were telephoned and asked to what extent they achieved their targets. RESULTS: The participants' satisfaction from the whole course was high (x: 8.65 ± 1.06). In the communication skills evaluation form, the participants stated that they would mainly use their communication and empathy skills during donor family encounters. The participants' mean post-test score was high (x: 96.0 ± 3.8). During the SDFEs, 70% of the respondents' performance was considered sufficient. Telephone interviews conducted with the questionnaire revealed that 77.6% of the targets were fulfilled. CONCLUSION: It can be said that the course affected the participants in terms of implementing their knowledge and communication skills related to family encounters.
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OBJECTIVE: This study introduced the modified version of the Organ Transplantation Coordinator course including simulated donor family encounters (SDFEs) and communication skills. It also evaluated participants' opinions and achievement levels, and how they implemented what they learned in the course in their work settings. METHODS: The course used the modified Analysis, Design, Development, Implementation, and Evaluation model and was evaluated in 3 steps. The participants' views were obtained using the course overall evaluation form and communication skills evaluation form, their success was assessed with the posttest and SDFEs evaluation form, and the effects of what they learned during the course on their work settings were assessed through telephone interviews. At this step, the participants were asked to write letters about the targets they intended to achieve in their work settings. The letters were analyzed with the content analysis method, and a questionnaire consisting of 105 targets was developed. A year later the participants were telephoned and asked to what extent they achieved their targets. RESULTS: The participants' satisfaction from the whole course was high (x: 8.65 ± 1.06). In the communication skills evaluation form, the participants stated that they would mainly utilize their communication and empathy skills during donor family encounters. The participants' mean posttest score was high (x: 96.0 ± 3.8). During the SDFEs, 70% of the respondents' performance was considered sufficient. Telephone interviews conducted with the questionnaire revealed that 77.6% of the targets were fulfilled. CONCLUSIONS: It can be said that the course affected the participants in terms of implementing their knowledge and communication skills related to family encounters.
Subject(s)
Attitude of Health Personnel , Education, Continuing/methods , Professional-Family Relations , Simulation Training/methods , Tissue and Organ Procurement/methods , Communication , Empathy , Female , Humans , Male , Personal Satisfaction , Program Evaluation , Surveys and Questionnaires , Tissue and Organ Procurement/organization & administration , TurkeyABSTRACT
OBJECTIVE: To evaluate whether symptoms and recurrence would differ with and without Cu-IUD removal in patients with concomitant biofilm forming Candida spp. METHODS: The data of 270 consecutive patients wearing TCu380A Cu-IUD were evaluated. Among these patients, 100/270 were found to have Candida spp. isolated from the tail of Cu-IUD or vaginal samples. These patients were investigated in four groups: Group 1 (n = 24; Biofilm (+), Cu-IUD removed), Group 2 (n = 14; Biofilm (+), Cu-IUD not removed), Group 3 (n = 29; Biofilm (-), Cu-IUD removed), Group 4 (n = 33; Biofilm (-), Cu-IUD not removed). Patients in each group were followed for clinical signs and symptoms for 8-16 months and compared to each other. RESULTS: Symptoms, physical findings and candida positivity have decreased statistically significantly in Group 1 one year after removal of Cu-IUD (95.8% vs. 4.2%, p < 0.01; 95.8% vs. 4.2%, p < 0.01; 100% vs. 8.3%, p < 0.01 respectively). In Group 2, symptoms, physical findings and candida positivity have decreased after follow-up, but without a statistical significance. In Group 3, all the parameters have decreased, but only decrease in candida positivity has reached statistical significance (100% vs. 48.3%, p < 0.01). In Group 4 - as in Group 1- symptoms, physical findings and candida positivity have decreased statistically significantly (48.5% vs. 18.2%, p = 0.01; 72.7% vs. 48.5%, p = 0.05; 100% vs. 51.5%, p < 0.01 respectively). CONCLUSION: Biofilm forming microorganisms should be considered in the management of vaginal infections or symptoms for safer use of intrauterine devices.
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Biofilms/growth & development , Candida/growth & development , Candidiasis, Vulvovaginal/therapy , Intrauterine Devices, Copper/microbiology , Adult , Candida/isolation & purification , Female , Humans , Intrauterine Devices, Copper/adverse effects , Middle Aged , RecurrenceABSTRACT
Using non-equilibrium Green function formalism in conjunction with density functional theory, we explore the spin-polarized transport characteristics of several planar n-acene molecules suspended between two semi-infinite Ni electrodes via the thiol group. We examine the spin-dependence transport on Ni-n-acenes-Ni junctions, while the number of fused benzene rings varies between 1 and 15. Intriguingly, the induced magnetic moments of small acene molecules are higher than that of longer acene rings. The augmentation of fused benzene rings affects both the magnetic and transport features, such as the transmission function and conductance owing to their coupling to the Ni surface contacts via the anchoring group. The interplay between the spin-polarized transport properties, structural configuration and molecular electronic is a fortiori essential in these attractive molecular devices. Thus, this can conduct to the engineering of the electron spin transport in atomistic and molecular junctions. These prominent molecules convincingly infer that the molecular spin valves can conduct to thriving molecular devices.
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Granuloma/diagnosis , Prostatitis/diagnosis , Biopsy, Needle , Eosinophilic Granuloma/diagnosis , Eosinophilic Granuloma/pathology , Granuloma/pathology , Humans , Male , Postoperative Complications/diagnosis , Postoperative Complications/pathology , Prostatitis/pathology , Transurethral Resection of Prostate , Tuberculoma/diagnosis , Tuberculoma/pathology , Tuberculosis, Male Genital/diagnosis , Tuberculosis, Male Genital/pathologyABSTRACT
Spin-polarized transport properties are determined for pentacene sandwiched between Ni surface electrodes with various anchoring ligands. These calculations are carried out using spin density functional theory in tandem with a non-equilibrium Green's function technique. The presence of a Se atom at the edge of the pentacene molecule significantly modifies the transport properties of the device because Se has a different electronegativity than S. Our theoretical results clearly show a larger current for spin-up electrons than for spin-down electrons in the molecular junction that is attached asymmetrically across the Se linker at one side of the Ni electrodes (in an APL magnetic orientation). Moreover, this molecular junction exhibits pronounced NDR as the bias voltage is increased from 0.8 to 1.0 V. However, this novel NDR behavior is only detected in this promising pentacene molecular device. The NDR in the current-voltage (I-V) curve results from the narrowness of the density of states for the molecular states. The feasibility of controlling the TMR is also predicted in these molecular device nanostructures. Spin-dependent transmission calculations show that the sign and strength of the current-bias voltage characteristics and the TMR could be tailored for the organic molecule devices. These molecular junctions are joined symmetrically and asymmetrically between Ni metallic probes across the S and Se atoms (at the ends of the edges of the pentacene molecule). Our theoretical findings show that spin-valve phenomena can occur in these prototypical molecular junctions. The TMR and NDR results show that nanoscale junctions with spin valves could play a vital role in the production of novel functional molecular devices.
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We investigated the efficacy and safety of Hepatitis B vaccine (HBVac) in steroid sensitive nephrotic syndrome (SSNS) children. 41 patients with SSNS and 30 controls were vaccinated with HBVac(Engerix B(®)). Patients were divided into 3 subgroups:full dose steroid users, alternate-day steroid users and steroid non-users. Seroconversion rate was lower in steroid users than non-users at the 6th(p=0.015) and 12th(p=0.036) months. Antibody to Hepatitis B surface antigen(HBsAb) titers were significantly different between subgroups and controls at the 15th month. However, HBsAb and response rates were not different between subgroups at the 12th and 15th months (p>0.05). Five patients were unresponsive to HBVac. Relapse rates after the vaccination were higher than those in the prevaccination period (p=0.002). HBVac is less effective in producing immune response in SSNS children with steroid therapy. HBVac may trigger relapse in some patients. We recommend HBVac to SSNS children with low dose steroid therapy or after steroids are discontinued.