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This research focuses on the first demonstration of NO2Lw (2-hydroxy-3-nitronaphthalene-1,4-dione) as a photosensitizer and TiO2, ZnO, and Nb2O5 as photoanode materials for dye-sensitized solar cells (DSSCs). The metal-free organic photosensitizer (i.e., nitro-group-substituted naphthoquinone, NO2Lw) was synthesized for this purpose. As a photoanode material, metal oxides, such as TiO2, ZnO, and Nb2O5, were selected. The synthesized NO2Lw contains an electron-withdrawing group (-NO2) and anchoring groups (-OH) that exhibit absorption in the visible range. The UV-visible absorbance spectrum of NO2Lw demonstrates the absorption ascribed to ultraviolet and visible region charge transfer. The NO2Lw interacts with the TiO2, ZnO, and Nb2O5 photoanode, as shown by bathochromic shifts in wavelengths in the photosensitizer-loaded TiO2, ZnO, and Nb2O5 photoanodes. FT-IR analysis also studied the bonding interaction between NO2Lw and TiO2, ZnO, and Nb2O5 photoanode material. The TiO2, ZnO, and Nb2O5 photoanodes loaded with NO2Lw exhibit a shift in the wavenumber of the functional groups, indicating that these groups were involved in loading the NO2Lw photosensitizer. The amount of photosensitizer loading was calculated, showing that TiO2 has higher loading than ZnO and Nb2O5 photoanodes; this factor may constitute an increased JSC value of the TiO2 photoanode. The device performance is compared using photocurrent-voltage (J-V) curves; electrochemical impedance spectroscopy (EIS) measurement examines the device's charge transport. The TiO2 photoanode showed higher performance than the ZnO and Nb2O5 photoanodes in terms of photoelectrochemical properties. When compared to ZnO and Nb2O5 photoanodes-based DSSCs, the TiO2 photoanode Bode plot shows a signature frequency peak corresponding to electron recombination rate toward the low-frequency region, showing that TiO2 has a greater electron lifetime than ZnO and Nb2O5 photoanodes based DSSCs.
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The rapid proliferation of cardiomyocytes in mammals occurs during fetal life. But in postnatal life, this capacity of proliferation is reduced or lost as they exit the cell cycle. However, the cardiomyocytes don't show the same activity for different species. In human fetuses or in adult life, the capacity of the proliferation of cardiomyocytes and their response to an injury are not understood yet. In this study, we have done an immunohistochemical study using phospho-histone H3 (PHH3) to observe human fetal cardiomyocytes' proliferative activity. The heart specimens from the fetal autopsy of spontaneously aborted and stillborn human fetuses were subjected to immunohistochemical study using PHH3 antibody, and comparison between the PHH3 index (number of PHH3 positive cells per 1000 number of cardiomyocytes/high power field [HPF]) of myocardial regions was done using appropriate statistical tests. A total of 17 fetal hearts were included in our study. In the left ventricle, right ventricle, right atrium, and interventricular septum, the PHH3 index of myocardium was significantly higher over the pericardial region (p-value 0.002, p-value <0.001, <0.001, and 0.009 respectively) as compared to the region of over the endocardium and the middle part of the myocardium. The PHH3 index of the pericardial region of the left ventricle was significantly correlated with the maximum thickness of the left ventricle.
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PURPOSE: Medical institutions in India have employed different periodic formative assessment (FA) methods with variable impact. The formative evaluation must incorporate feedback to improve learning. Formative assessment has helped inexperienced students apprehend their weaknesses, make choices, prepare for summative exams, and allow teachers to identify regions wherein students may also need aid. This study attempts to quantify the impact of the weekly, monthly, and semester formative assessments and view it retrospectively through the lens of complex adaptive systems and social sustainability principles. METHODS: We used a post-exam survey and statistical analysis to compare the students' performance between the timely periodic formative assessments in a competency-based curriculum. The cohort consisted of 2018 (semester), 2019 (weekly), and 2020 (monthly) first-year medical students. Cronbach alpha, spearman's correlation coefficient, descriptive statistics, and repeated measure analysis of variance were used to explore the reliability and relationship between formative assessment and summative scores of each cohort and find any significant difference. The authors also analyzed the accordance between the FA exam performance and students' perceptions, deduced broad themes, and discussed the appropriateness and feasibility of students' suggestions for changes. RESULTS: A significant correlation was found only between the weekly formative assessment and summative scores (r=0.74, p=0.01). The analysis of variance established significant differences between all summative scores of respective periodic formative assessments. The weekly formative assessment showed the highest mean summative examination scores. This study helped comprehend preclinical students' apprehension after the intervention of periodic formative assessments. The students found this intervention helpful in driving and detecting gaps in learning but preferred focused feedback, clinically oriented practices, and countered mental health issues. CONCLUSION: The continuous periodic formative assessment model had a valid educational impact but was not sustainable according to social sustainability principles. A complex adaptive framework can be utilized to make it sustainable.
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INTRODUCTION: Voluntary body donation (VBD) programs form the backbone of cadaveric teaching and learning in medical schools. It benefits the medical fraternity the most. Yet, there is a dearth of VBD practice among medical students. We aimed to understand the knowledge and attitude of first-year medical students in a tertiary institute with a systematic review of willingness toward VBD among undergraduate students worldwide. METHODS: The first-year medical undergraduates were given a 12-item questionnaire to assess their knowledge and attitude toward VBD. Statistical tests were applied to analyze the difference between the variables. We systematically searched Google Scholar, PubMed, and SCOPUS databases until October 15, 2022. Data concerning knowledge, awareness, and attitude toward VBD among undergraduates of medical backgrounds were extracted and analyzed qualitatively. RESULTS: A total of 82.5% of students returned the completed responses. A significant association was seen between their attitudes toward whole body donation by strangers (p=0.043) and family members (p=0.035). The religion of the participants significantly affected their opinions on VBD and their willingness to pledge themselves (p=0.034). For the review, 20 studies were selected to be analyzed qualitatively. These studies included 4232 undergraduate students globally who were assessed for knowledge, awareness, and attitude toward VBD. Around 50% of the studies were published in India. The first study included was published in 2008. Seven studies were exclusively conducted on medical undergraduates, while the rest consisted of a mixed cohort. The attitude and knowledge of medical undergraduates on VBD were assessed via questionnaires containing both open-ended and closed-ended questions. CONCLUSION: Based on observations from our survey and review, we concluded that while undergraduate students have a highly positive attitude toward VBD, their rate of pledging is low. The most prominent barrier to this attitude is their experience with cadavers in the dissection hall. Hence, we recommend a revisit of cadaver handling practices and the establishment of appropriate protocols for safe and deferential cadaver handling.
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Hyperostosis Frontalis Interna (HFI), a condition that has been sparsely explained till now, is a benign, asymptomatic, and irregular thickening of the endocranium of the frontal bone. It is found to be predominantly present in post-menopausal women during incidental X-ray or CT/MRI of the skull. The prevalence of HFI is documented in different populations, but in the Indian population, it is comparatively rare. Thus, we discuss a serendipitous finding of HFI in an Indian skull. This rare variation was noted in dry Indian human skulls. Gross features of the skull were noted, and it was an adult female skull. The area was decalcified, paraffin-embedded, and stained with Haematoxylin and Eosin. The skull bone was also subjected to plain X-ray/CT investigation. The X-ray skull of 50+ year female type features in anteroposterior and lateral view showed widening of the diploic spaces 8-10 mm with ill-defined hyperdense areas in the frontal region. Changes in computed tomography were noted. HFI often has nonspecific and benign symptoms. However, in severe cases, widespread clinical implications starting from headache, motor aphasia, parkinsonism, and depression can occur, and thus we all should be aware of it.
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The liver is a very dynamic organ. Still, the gross anomalies of the liver are sparse. The accessory lobe of the liver is a rare anatomical variation with a prevalence of less than 1%. We present a case of an accessory lobe and two accessory grooves of the liver in a cadaver. The accessory lobe was an isolated anomaly, sessile in presentation, and attached to normal liver parenchyma. Although accessory lobes are rare, knowledge about them will reiterate to surgeons and radiologists to be mindful of them and to avoid misdiagnosis.
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Background Morphometric measurement of the sacrum is crucial due to its active involvement in the instrumentation for lumbar pathologies. From screw placement to stabilization procedures for the spine, the sacrum remains a site of surgical importance. Thus, the purpose of this study was to generate baseline data by comparing two techniques, namely, osteometry in dry bones and CT scan imaging. Methodology In this study, 30 dry, fully ossified, disarticulated sacra were studied for osteometry, and 60 CT scan reports of patients with lumbar pathologies were retrospectively evaluated. In both cases, similar parameters were measured. The mean values were determined, the two methods were compared, and statistical analysis was performed. Results Among the 30 dry bone samples, 33.3% (10 out of 30) were males, while 55% of the CT scan group were males. Correlation between the different measurements in the CT scan group suggested that the vertebral body maximum width of S1 had a significant positive correlation with the vertebral body height of S1, sacral height, sacral breadth, transverse diameter of auricular surface, and vertical diameter of auricular surface. Statistically significant higher values (P < 0.001) were observed for the vertebral body mid diameter of S1, vertebral body height of S1, pedicle width, and pedicle depth measurements in the dry bone group compared to the CT scan group. Conclusions The efficiency of anaesthetic blocks can be increased if the parameters are evaluated beforehand. Moreover, sexual dimorphism of the bone can account for the varied results of the parameters, indicating the necessity to conduct gender-based studies in a wider population.
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PURPOSE: The spleen is a fist-sized largest lymphoid organ located in the left hypochondrium. It has a unique location, embryological and histological structure that differs significantly from other lymphoid organs. The present work was undertaken to study the microscopic and ultramicroscopic histogenesis patterns of the spleen in relation to gestational age. METHODS: The splenic tissue of nine aborted fetuses of various gestational ages was studied. For cytology study, special stains like Masson's trichrome, Periodic Acid-Schiff, and Reticulin were used; immunohistochemical staining was performed with triple antibodies (C-myc, Ki-67, and Ber-H2); and for ultrastructure study, aluminum mounted specimens coated with gold and argon gas were observed under scanning electron microscopy (SEM). RESULTS: Microscopy and immunohistochemistry showed the developmental changes in the spleen from the emergence of the primordium to the end of the embryonic period in all stages of fetogenesis. The spleen primordium of a fetus at the developmental stage of the primary vascular reticulum was seen in the first trimester fetuses. The primordium is comprised mainly of mesenchymal tissue; numerous lymphocytes invading the area surrounding the central artery forming the periarterial lymphoid sheaths (PALS) were seen surrounded by venous sinuses in the early second trimester fetuses. CONCLUSION: The organizational changes in the reticuloendothelial system and microstructure of the spleen during fetogenesis are very crucial to achieving adult morphology in the future. Histogenesis of the fetal spleen follows a multistep process depending upon the gestational age. Any deviation from normalcy may lead to structural and functional abnormality later in life.
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Osteomas are most common among all primary bone tumors of skull bones. They are usually asymptomatic due to their small size and slow growth. They are found incidentally on imaging studies for other neurologic symptoms. Osteoma may be single or multiple when present. They should be differentiated from meningiomas, chordomas, schwannomas, and parosteal osteosarcoma by using different diagnostic methods, including histopathologic study. During routine dissection for MBBS students in an 87 years old female cadaver, we found multiple (seven in number) irregular, lobulated bony masses/structures. Their positions were different with respect to the layers of meninges. Some were present between the dura mater and arachnoid mater compressing the adjacent brain tissues forming impressions on them, and some were outside the dura mater. So, into the previously existing classification, we want to add a new variety under the type b category, i.e., mixed type (intraparenchymal, dural, skull vault) as pointed under the subtype V, which is found in our case.
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Cervical disc arthroplasty (CDA) is a newer alternative to the traditional fusion, in patients with prolapsed cervical disc in the younger eligible patient aiming to provide mobility similar to the native disc and by some ways preventing the adjacent segment disease. The rising popularity of its early success has seen emergence of a number of products in the market. In a country where cost remains an important constraint for the patients, local design products are available to cater to these lesser privileged patients. The present complication is an acute dissociation of components from such a product wherein the implant was retrieved and fusion was done. The patient was subsequently discharged uneventfully.
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Degeneração do Disco Intervertebral , Fusão Vertebral , Artroplastia/efeitos adversos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Discotomia , Humanos , Degeneração do Disco Intervertebral/cirurgia , Próteses e Implantes , Fusão Vertebral/efeitos adversos , Resultado do TratamentoRESUMO
The present study attempted to validate the "Burcev freehand method" based on anatomical observations in Indian cadavers. The study was conducted on 32 cervical pedicle screws (CPSs) that were placed in four cadavers by the authors according to the "freehand technique," described by Burcev et al, without the aid of fluoroscopy and the trajectory verified by computed tomography scans. The screws were designated as satisfactory, permissible, or unacceptable. Descriptive variables were represented in number and percentages, continuous variables were represented as mean ± standard deviation (SD). Of the 32 CPSs placed, 24 (75%) exhibited a satisfactory position, 1 (3%) exhibited a permissible position, and 7 (22%) exhibited an unacceptable position. Of the seven CPSs in the unacceptable group, four exhibited a lateral breach and three exhibited a medial breach, whereas the CPS in the permissible group exhibited a medial breach. The overall angle with contralateral lamina in the horizontal plane in terms of mean ± SD was 175.43 ± 2.82, 169.49, and 169.65 ± 6.46 degrees in the satisfactory, permissible, and unacceptable groups, respectively. In the sagittal plane, the screws exhibited an angle of 88.15 ± 3.56 degrees. No breach was observed superiorly or inferiorly. The "Burcev technique" is replicable with similar results in cadavers. Further studies must be conducted in a clinical setting to ensure its safety.
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The sacral canal is the continuation of the vertebral canal in the sacrum. The sacral canal contains spinal meninges, lumbar and sacral part of spinal nerves and filum terminale. So sacral canal has been used for the caudal epidural block. During routine osteology demonstration classes for undergraduate students, we observed a dry human sacrum with complete agenesis of the dorsal wall of the sacral canal. Knowledge of these variations is important to diagnose lower back pain, sciatica, caudal regression syndrome and to avoid complications related to caudal epidural block and other spinal surgeries like in placement of screw for spinal fusion.
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Arterial variations in upper limbs are often reported commonly. Superficial arterial variations accounting for 4.2% of all arterial variations are hazardous during any invasive procedures of the upper limb, from routine intravenous injections to surgeries. Arterial variations are usually associated with inverted or absent palmaris longus. Palmaris profundus, a rare anomalous variation of palmaris longus has been reported in carpal tunnel syndrome as its tendon was associated with median nerve in the carpal tunnel. The authors reported a unique variation in the upper limb arterial pattern-the presence of bilateral superficial brachioulnar artery associated with unilateral palmaris profundus muscle and an abnormal radicle of musculocutaneous nerve to the median nerve in the left side.
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PURPOSE: The spotter's (objectively structured practical examination) is an assessment tool which is widely used to test the practical knowledge of anatomy extensively. In Indian context it is used as an inclusive model in the gross anatomy practical examination and the marks allotted to it varies. The traditional spotter examination often has been blamed for only incorporating the initial levels of revised Bloom's taxonomy. This study retrospectively analysed the pre-professional spotter's examination score and tested its efficacy in terms of reliability, internal consistency, validity, educational impact, and resource intensiveness. METHODS: The summative data of student's score on four different days of unrepeated spotter's examination and final theory examination score was collected and tabulated. These four group of students acted as independent cohorts. The difficulty index (DI), point biserial correlation (PBC), Cronbach α (CA) and descriptive statistics of each cohort were calculated. Revised bloom taxonomy rating was applied to spotter's. RESULTS: We found heterogenous distribution of spotter's in each cohort according to DI. The PBCs and CA of each cohort were acceptable. The majority of spotter's tested the cognitive and comprehension domain of revised bloom's taxonomy. There was nonsignificant difference between mean scores of cohorts but we found low positive significant correlation between theory and spotter's score. CONCLUSION: We concluded that the construct of spotter's was reliable, internally consistent, had fair validity, variable educational impact, and sustainable resource intensiveness. We propose urgent redesigning of spotter's to include higher level of taxonomy to comply with emerging curricular changes.
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Desempenho Acadêmico , Anatomia/educação , Currículo , Educação Médica , Avaliação Educacional/métodos , Aprendizagem , Estudantes de Medicina , Classificação , Cognição , Compreensão , Avaliação Educacional/normas , Humanos , Índia , Conhecimento , Aprendizagem/classificação , Reprodutibilidade dos Testes , Estudos Retrospectivos , EnsinoRESUMO
Thymus is an encapsulated organ having its bilateral origin from the third pharyngeal pouch. It appears to be a single organ but actually it is bilobed. It attains its maximum development at puberty and then it begins to involute. The parenchyma is replaced by adipocytes and lymphocyte production declines. Here we present a large thymus with a small area of persistent active tissue in it which was obtained during routine undergraduate dissection class. Tissues taken from different quadrants of the large thymic mass were processed, embedded in paraffin and sections were taken for hematoxylin and eosin staining which showed presence of thymic tissue in only one quadrant. Further sections from that quadrant was treated with cytokeratin to confirm its epithelial origin. Therefore knowledge of a large persistent thymus will be helpful to the radiologists and surgeons for making differential diagnosis and in avoiding unnecessary surgical intervention.
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Midgut malrotation and incomplete rotation are common causes of neonatal intestinal obstruction. At end of 10 week of intrauterine life, cecum will be placed in subhepatic region temporarily and descends to right lower quadrant by eleventh week. Arrest of cecum in subhepatic region or undescended cecum is a rare congenital anomaly of mid gut. Usually, it remains asymptomatic and is diagnosed incidentally. If any pathology occurs in anomalous part, like appendicitis then the diagnosis and treatment will be challenging in all age groups. Variation in blood supply have also been reported with anomalies leading to iatrogenic injuries during colonoscopy and surgeries. Lack of knowledge of these rare variations may lead to delayed diagnosis of appendicitis leading to perforation and surgical emergencies. In the present case, we describe an undescended cecum and its associated variation in branching pattern of superior mesenteric artery.