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Papers by sahil chhabra

Handbook of Biochemistry Spotting, 2016

Handbook of Biochemistry Spotting, 2016

Indian Pediatrics, 2021

Context-Feedback processes are intricate, generally misunderstood, hard to execute efficiently, a... more Context-Feedback processes are intricate, generally misunderstood, hard to execute efficiently, and often fail in their goals to influence students learning. Research highlights that students usually do not value the benefits of feedback. This paper reviews the literature on the definition, purpose, and models of feedback; and on exploring why some students do not value feedback, what factors are influencing the effectiveness of feedback, and how to improve the efficacy of feedback. Evidence acquisition: The relevant articles were searched through 'Google Scholar,' 'CINAHIL' and 'PubMed' using the key terms-"Student feedback," "Frameworks of feedback," "Barriers to effective feedback," and "Students' perspectives on feedback." The search criteria included: review and original research articles in the English language, published in high-impact journals in the past ten years. Results: The results of different studies have illuminated diverse factors demanding the attention of educators to the effectiveness of feedback. Personal, relational, procedural, and environmental factors seem to affect the utility of feedback. To be effective, feedback should be actionable, non-judgmental, descriptive, and specific should be based on observable behavior and should be given at a mutually agreeable time and place. Conclusion: The efficacy of feedback can be enhanced by creating students' feedback literacy, addressing students' perceptions and expectations, encouraging productive educational alliances, and improving procedural elements of feedback and environmental conditions.

Medical Science Educator, 2022

Introduction This study investigated the perspectives of medical students on the factors influenc... more Introduction This study investigated the perspectives of medical students on the factors influencing empathy development during their undergraduate training. Methodology A descriptive phenomenological approach was used to generate illustrations of empathy development and decline that had educational significance and applicability. Individual online semi-structured interviews were conducted to elicit experiential details from twelve final-year medical students. The interview recordings were transcribed verbatim, and data were analysed employing Braun and Clarke’s thematic analysis method. Results The self-reported empathic behavior of medical students seemed to have improved with time in medical school. Students attributed their empathy development to real patient encounters, positive role-modelling by teachers, and attainment of confidence and personal maturity. They identified exams, academic overload, time constraints, personal stresses, negative role models, unconducive learning environments, and lack of formal empathy training as barriers to empathy development. Conclusion Medical institutes should identify and address the barriers to empathy development and encourage the holistic development of medical students. Furthermore, medical educators should model their behavior accurately for their increasing roles and responsibilities and support the students in their empathic expressions with patients.

Tropical Journal of Pathology and Microbiology, 2019

Introduction: Central nervous system (CNS) neoplasms, in India, constitute 1.9% of all cancers an... more Introduction: Central nervous system (CNS) neoplasms, in India, constitute 1.9% of all cancers and in U.S. adults-2% of all cancers. Many of the non-neoplastic CNS lesions can clinically & radiologically simulate brain tumours. In such cases, histopathological examination (HPE) can be helpful in differentiating between neoplastic and non-neoplastic etiologies. Materials and Methods: This retrospective descriptive study of histopathological analysis of brain tumours was carried out in TMMC&RC, Department of Pathology from January 2015 to December 2018. The biopsies were processed by routine histological techniques and H&E stained sections were analyzed. Special stains and IHC were performed wherever appropriate. The diagnosed brain tumours were classified according to WHO 2016 classification system. Results: A total of 96 CNS biopsies were studied. The neoplasms constituted 62 (64.6%) cases, which included 60 (96.8%) primary, 1 (1.6%) metastatic and 1 miscellaneous lesion (1.6%). The 3 most common primary tumours were Astrocytic tumours, Schwannomas and Meningiomas. About 34(35.4%) cases were non neoplastic out of which the 2 most common lesions were: Cystic Lesions and non-specific inflammation. Patients' age ranged from 5 days to 80 years. The ratio of number of male and female patients was 1:1.67. IHC for Glial Fibrillary Acidic Protein (GFAP) was positive in astrocytomas and mixed neuronal-glial tumours. Conclusion: The present study provides information regarding the spectrum and frequency of various CNS lesions in our area and concludes that histological examination of biopsies is gold standard for accurate diagnosis of various lesions of CNS when coupled with radiological and clinical data.

Vehicular Ad-hoc Network (VANET) is used to provide the efficient network environment for a large... more Vehicular Ad-hoc Network (VANET) is used to provide the efficient network environment for a large vehicle system in which the vehicle speed is very fast. We provide the transmission of safety and non-safety messages among vehicles. If the message is receiving in less time so that the drivers can take the effective decision. For this purpose efficient safety message technique is used that is FSR. This technique provides advantages of less control message exchange by abandoning the exhausted food source. A next forwarder is elected on the basis of fitness value and that node is the node in that region. Using this technique we can save the bandwidth. It is more efficient in high density network and also called as ABC based FSR. Keywords— Artificial Bee Colony (ABC), Fisheye State Routing (FSR), Routing protocols

Handbook of Biochemistry Spotting, 2016

Handbook of Biochemistry Spotting, 2016

Indian Journal of Forensic Medicine & Toxicology, 2018

Histopathological examination of heart autopsies is routinely done in medico-legal cases to ascer... more Histopathological examination of heart autopsies is routinely done in medico-legal cases to ascertain the cause of death. Cardiovascular disease is the leading cause of deaths worldwide. Myocarditis is clinically and pathologically defined as inflammation of the myocardium. Autopsy studies have reported an incidence of 3.5% to as high as 10%. In the present study comprising of 235 heart autopsies, the diagnosis of myocarditis is made in only two cases which constituted 0.8% of the total heart autopsies. This rate of myocarditis in our autopsy study is far lower than the published studies. The aim of our study is to assess the frequency of fatal course myocarditis in a consecutive series of autopsies and to describe the histologic features of the disease.

Indian Journal of Medical and Paediatric Oncology, 2020

Cervical teratomas are very rare tumors, accounting for approximately 3%-5% of all pediatric tera... more Cervical teratomas are very rare tumors, accounting for approximately 3%-5% of all pediatric teratomas with predominance in females. Most common site of cervical teratoma is sacrococcygeal region and occurrence in cervical region is a rare presentation. We present a case of cervical teratoma in a 4-month-old male infant presenting as neck mass mimicking as neuroblastoma with differentiation on fine-needle aspiration. The final diagnosis of mature teratoma was made on histopathological examination.

Annals of Pathology and Laboratory Medicine, 2020

The Bombay Blood Group (Oh) is characterized by absence of normal ABH antigens and presence of co... more The Bombay Blood Group (Oh) is characterized by absence of normal ABH antigens and presence of corresponding antibodies in serum. This blood group is suspected when a sample doesn't show any reaction to anti-A and anti-B antibodies just like a normal O group would do but shows agglutination in reverse grouping or during antibody screening. Present case report highlights a case of 25 year old female who was incidentally detected having Bombay blood group and on further evaluation one sibling and two first degree cousins were also detected having Bombay blood group. Such a clustering of Bombay blood group cases in a single family is very rare and has never been reported in Punjab as per literature.

International Journal of Contemporary Medical Research [IJCMR], Jun 1, 2019

Introduction: Fine needle aspiration cytology (FNAC) has become an increasingly popular technique... more Introduction: Fine needle aspiration cytology (FNAC) has become an increasingly popular technique for assessment and initial diagnosis of breast lumps as it is the least invasive technique for obtaining a cytological diagnosis and is of high accuracy if done by experienced personnel. Thyroid hormone receptors affect both the normal breast cell differentiation and breast cancer cell proliferation, with effects of thyroid hormones similar to those caused by estrogens. Relationship between thyroid disease, such as nodular hyperplasia, hyperthyroidism and thyroid cancer, with breast cancer was demonstrated in several studies. In the present study, we have evaluated the correlation of cytomorphological diagnosis of breast lesions with thyroid profile. Material and Methods: Total of 80 cases were included in the study and all necessary statistical analysis was done including the percentages, means, standard deviations, ranges and p values. Results: Triiodothyronine (T3) and Tetraiiodothryronine (T4) levels were statically significantly lower among participants with malignant breast lesions as compared to benign breast lesions.(p < 0.01).However mean values of both were normal in both these groups. Thyroid stimulating hormone (TSH) levels among study participants with malignant breast lesions were statistically higher than those of benign breast lesions. However mean in both these groups was within normal range. Conclusion: No significant correlation between thyroid profile and breast lesions was established. But the effect of thyroid hormone on breast cancer clearly requires further research.

International Journal of Contemporary Medical Research [IJCMR], Aug 1, 2019

Introduction: Quality control of blood and its components ensures the availability of high qualit... more Introduction: Quality control of blood and its components ensures the availability of high quality product with maximum efficacy and minimal risk to recipients. As per standard guidelines, for quality assurance of FFP, 1% of all the units prepared or 4 units per month are tested for stable coagulation factors: Factor VIII and Fibrinogen levels. Material and methods: The retrospective data was collected from archives of blood bank from the period of 1st January 2017 to 31st December 2017 in AIMSR, Bathinda. Out of total 3476 units collected, 2155 were processed for component separation. 1.9% of Fresh Frozen plasma (41/2155) were tested for total volume, fibrinogen content and factor VIII levels for quality control with the help of semi-automated coagulometer. Results: 97.5% of FFP samples tested had factor VIII levels above 0.7 IU/mL and 100% of samples had fibrinogen content >200mg/dl. Conclusion: It is concluded that quality of FFP being prepared at our blood bank meets the international standards. Regular quality evaluation and maintenance of records helps to keep up the working standards and any deficiency can be checked and curtailed.

International Journal of Distributed Artificial Intelligence, 2019

In this article, a reversible data hiding technique is proposed to embed multiple segments of a s... more In this article, a reversible data hiding technique is proposed to embed multiple segments of a single message into a single cover image. This multiple message segment technique uses a pixel value ordering approach to embed the secret message. The splitting and randomization of the original secret message provides security from an attacker There are many digital formats for data hiding, like images, audio, and video, of which the digital image is the simplest format. Data hiding in image processing refers to inserting the secret message into digital images. Reversible data hiding (RDH) is a lossless technique, in which both the embedded secret message and the cover image is extracted by the receiver. The applications of RDH include medical and military imaging.

Journal of Chemical Information and Modeling, 2020

Cryo-electron microscopy (cryo-EM) single particle analysis has come a long way in achieving atom... more Cryo-electron microscopy (cryo-EM) single particle analysis has come a long way in achieving atomic-level resolution when imaging biomolecules. In order to obtain the best possible three-dimensional structure in cryo-EM, many parameters have to be carefully considered. Here we address the often-overlooked parameter of the pixel size, which describes the magnification of the image produced by the experiment. While efforts are made to refine and validate this parameter in the analysis of cryo-EM experimental data, there is no systematic protocol in place. Since the pixel size parameter can have an impact on the resolution and accuracy of a cryo-EM map, and the atomic resolution, three-dimensional structure models derived from it, we propose a computational protocol to estimate the appropriate pixel size parameter. In our protocol, we fit and refine atomic structures against cryo-EM map at multiple pixel sizes. The resulting fitted and refined structures are evaluated using the GOAP (Generalized Orientation-Dependent, All-atom Statistical Potential) score, which we found to perform better than other commonly used functions, such as Molprobity and the correlation coefficient from refinement. Finally, we describe the efficacy of this protocol in retrieving appropriate pixel sizes for several examples; simulated data based on yeast elongation factor 2, and experimental data from Gro-EL chaperone, beta-galactosidase and the TRPV1 ion channel.

Handbook of Biochemistry Spotting, 2016

Handbook of Biochemistry Spotting, 2016

Indian Pediatrics, 2021

Context-Feedback processes are intricate, generally misunderstood, hard to execute efficiently, a... more Context-Feedback processes are intricate, generally misunderstood, hard to execute efficiently, and often fail in their goals to influence students learning. Research highlights that students usually do not value the benefits of feedback. This paper reviews the literature on the definition, purpose, and models of feedback; and on exploring why some students do not value feedback, what factors are influencing the effectiveness of feedback, and how to improve the efficacy of feedback. Evidence acquisition: The relevant articles were searched through 'Google Scholar,' 'CINAHIL' and 'PubMed' using the key terms-"Student feedback," "Frameworks of feedback," "Barriers to effective feedback," and "Students' perspectives on feedback." The search criteria included: review and original research articles in the English language, published in high-impact journals in the past ten years. Results: The results of different studies have illuminated diverse factors demanding the attention of educators to the effectiveness of feedback. Personal, relational, procedural, and environmental factors seem to affect the utility of feedback. To be effective, feedback should be actionable, non-judgmental, descriptive, and specific should be based on observable behavior and should be given at a mutually agreeable time and place. Conclusion: The efficacy of feedback can be enhanced by creating students' feedback literacy, addressing students' perceptions and expectations, encouraging productive educational alliances, and improving procedural elements of feedback and environmental conditions.

Medical Science Educator, 2022

Introduction This study investigated the perspectives of medical students on the factors influenc... more Introduction This study investigated the perspectives of medical students on the factors influencing empathy development during their undergraduate training. Methodology A descriptive phenomenological approach was used to generate illustrations of empathy development and decline that had educational significance and applicability. Individual online semi-structured interviews were conducted to elicit experiential details from twelve final-year medical students. The interview recordings were transcribed verbatim, and data were analysed employing Braun and Clarke’s thematic analysis method. Results The self-reported empathic behavior of medical students seemed to have improved with time in medical school. Students attributed their empathy development to real patient encounters, positive role-modelling by teachers, and attainment of confidence and personal maturity. They identified exams, academic overload, time constraints, personal stresses, negative role models, unconducive learning environments, and lack of formal empathy training as barriers to empathy development. Conclusion Medical institutes should identify and address the barriers to empathy development and encourage the holistic development of medical students. Furthermore, medical educators should model their behavior accurately for their increasing roles and responsibilities and support the students in their empathic expressions with patients.

Tropical Journal of Pathology and Microbiology, 2019

Introduction: Central nervous system (CNS) neoplasms, in India, constitute 1.9% of all cancers an... more Introduction: Central nervous system (CNS) neoplasms, in India, constitute 1.9% of all cancers and in U.S. adults-2% of all cancers. Many of the non-neoplastic CNS lesions can clinically & radiologically simulate brain tumours. In such cases, histopathological examination (HPE) can be helpful in differentiating between neoplastic and non-neoplastic etiologies. Materials and Methods: This retrospective descriptive study of histopathological analysis of brain tumours was carried out in TMMC&RC, Department of Pathology from January 2015 to December 2018. The biopsies were processed by routine histological techniques and H&E stained sections were analyzed. Special stains and IHC were performed wherever appropriate. The diagnosed brain tumours were classified according to WHO 2016 classification system. Results: A total of 96 CNS biopsies were studied. The neoplasms constituted 62 (64.6%) cases, which included 60 (96.8%) primary, 1 (1.6%) metastatic and 1 miscellaneous lesion (1.6%). The 3 most common primary tumours were Astrocytic tumours, Schwannomas and Meningiomas. About 34(35.4%) cases were non neoplastic out of which the 2 most common lesions were: Cystic Lesions and non-specific inflammation. Patients' age ranged from 5 days to 80 years. The ratio of number of male and female patients was 1:1.67. IHC for Glial Fibrillary Acidic Protein (GFAP) was positive in astrocytomas and mixed neuronal-glial tumours. Conclusion: The present study provides information regarding the spectrum and frequency of various CNS lesions in our area and concludes that histological examination of biopsies is gold standard for accurate diagnosis of various lesions of CNS when coupled with radiological and clinical data.

Vehicular Ad-hoc Network (VANET) is used to provide the efficient network environment for a large... more Vehicular Ad-hoc Network (VANET) is used to provide the efficient network environment for a large vehicle system in which the vehicle speed is very fast. We provide the transmission of safety and non-safety messages among vehicles. If the message is receiving in less time so that the drivers can take the effective decision. For this purpose efficient safety message technique is used that is FSR. This technique provides advantages of less control message exchange by abandoning the exhausted food source. A next forwarder is elected on the basis of fitness value and that node is the node in that region. Using this technique we can save the bandwidth. It is more efficient in high density network and also called as ABC based FSR. Keywords— Artificial Bee Colony (ABC), Fisheye State Routing (FSR), Routing protocols

Handbook of Biochemistry Spotting, 2016

Handbook of Biochemistry Spotting, 2016

Indian Journal of Forensic Medicine & Toxicology, 2018

Histopathological examination of heart autopsies is routinely done in medico-legal cases to ascer... more Histopathological examination of heart autopsies is routinely done in medico-legal cases to ascertain the cause of death. Cardiovascular disease is the leading cause of deaths worldwide. Myocarditis is clinically and pathologically defined as inflammation of the myocardium. Autopsy studies have reported an incidence of 3.5% to as high as 10%. In the present study comprising of 235 heart autopsies, the diagnosis of myocarditis is made in only two cases which constituted 0.8% of the total heart autopsies. This rate of myocarditis in our autopsy study is far lower than the published studies. The aim of our study is to assess the frequency of fatal course myocarditis in a consecutive series of autopsies and to describe the histologic features of the disease.

Indian Journal of Medical and Paediatric Oncology, 2020

Cervical teratomas are very rare tumors, accounting for approximately 3%-5% of all pediatric tera... more Cervical teratomas are very rare tumors, accounting for approximately 3%-5% of all pediatric teratomas with predominance in females. Most common site of cervical teratoma is sacrococcygeal region and occurrence in cervical region is a rare presentation. We present a case of cervical teratoma in a 4-month-old male infant presenting as neck mass mimicking as neuroblastoma with differentiation on fine-needle aspiration. The final diagnosis of mature teratoma was made on histopathological examination.

Annals of Pathology and Laboratory Medicine, 2020

The Bombay Blood Group (Oh) is characterized by absence of normal ABH antigens and presence of co... more The Bombay Blood Group (Oh) is characterized by absence of normal ABH antigens and presence of corresponding antibodies in serum. This blood group is suspected when a sample doesn't show any reaction to anti-A and anti-B antibodies just like a normal O group would do but shows agglutination in reverse grouping or during antibody screening. Present case report highlights a case of 25 year old female who was incidentally detected having Bombay blood group and on further evaluation one sibling and two first degree cousins were also detected having Bombay blood group. Such a clustering of Bombay blood group cases in a single family is very rare and has never been reported in Punjab as per literature.

International Journal of Contemporary Medical Research [IJCMR], Jun 1, 2019

Introduction: Fine needle aspiration cytology (FNAC) has become an increasingly popular technique... more Introduction: Fine needle aspiration cytology (FNAC) has become an increasingly popular technique for assessment and initial diagnosis of breast lumps as it is the least invasive technique for obtaining a cytological diagnosis and is of high accuracy if done by experienced personnel. Thyroid hormone receptors affect both the normal breast cell differentiation and breast cancer cell proliferation, with effects of thyroid hormones similar to those caused by estrogens. Relationship between thyroid disease, such as nodular hyperplasia, hyperthyroidism and thyroid cancer, with breast cancer was demonstrated in several studies. In the present study, we have evaluated the correlation of cytomorphological diagnosis of breast lesions with thyroid profile. Material and Methods: Total of 80 cases were included in the study and all necessary statistical analysis was done including the percentages, means, standard deviations, ranges and p values. Results: Triiodothyronine (T3) and Tetraiiodothryronine (T4) levels were statically significantly lower among participants with malignant breast lesions as compared to benign breast lesions.(p < 0.01).However mean values of both were normal in both these groups. Thyroid stimulating hormone (TSH) levels among study participants with malignant breast lesions were statistically higher than those of benign breast lesions. However mean in both these groups was within normal range. Conclusion: No significant correlation between thyroid profile and breast lesions was established. But the effect of thyroid hormone on breast cancer clearly requires further research.

International Journal of Contemporary Medical Research [IJCMR], Aug 1, 2019

Introduction: Quality control of blood and its components ensures the availability of high qualit... more Introduction: Quality control of blood and its components ensures the availability of high quality product with maximum efficacy and minimal risk to recipients. As per standard guidelines, for quality assurance of FFP, 1% of all the units prepared or 4 units per month are tested for stable coagulation factors: Factor VIII and Fibrinogen levels. Material and methods: The retrospective data was collected from archives of blood bank from the period of 1st January 2017 to 31st December 2017 in AIMSR, Bathinda. Out of total 3476 units collected, 2155 were processed for component separation. 1.9% of Fresh Frozen plasma (41/2155) were tested for total volume, fibrinogen content and factor VIII levels for quality control with the help of semi-automated coagulometer. Results: 97.5% of FFP samples tested had factor VIII levels above 0.7 IU/mL and 100% of samples had fibrinogen content >200mg/dl. Conclusion: It is concluded that quality of FFP being prepared at our blood bank meets the international standards. Regular quality evaluation and maintenance of records helps to keep up the working standards and any deficiency can be checked and curtailed.

International Journal of Distributed Artificial Intelligence, 2019

In this article, a reversible data hiding technique is proposed to embed multiple segments of a s... more In this article, a reversible data hiding technique is proposed to embed multiple segments of a single message into a single cover image. This multiple message segment technique uses a pixel value ordering approach to embed the secret message. The splitting and randomization of the original secret message provides security from an attacker There are many digital formats for data hiding, like images, audio, and video, of which the digital image is the simplest format. Data hiding in image processing refers to inserting the secret message into digital images. Reversible data hiding (RDH) is a lossless technique, in which both the embedded secret message and the cover image is extracted by the receiver. The applications of RDH include medical and military imaging.

Journal of Chemical Information and Modeling, 2020

Cryo-electron microscopy (cryo-EM) single particle analysis has come a long way in achieving atom... more Cryo-electron microscopy (cryo-EM) single particle analysis has come a long way in achieving atomic-level resolution when imaging biomolecules. In order to obtain the best possible three-dimensional structure in cryo-EM, many parameters have to be carefully considered. Here we address the often-overlooked parameter of the pixel size, which describes the magnification of the image produced by the experiment. While efforts are made to refine and validate this parameter in the analysis of cryo-EM experimental data, there is no systematic protocol in place. Since the pixel size parameter can have an impact on the resolution and accuracy of a cryo-EM map, and the atomic resolution, three-dimensional structure models derived from it, we propose a computational protocol to estimate the appropriate pixel size parameter. In our protocol, we fit and refine atomic structures against cryo-EM map at multiple pixel sizes. The resulting fitted and refined structures are evaluated using the GOAP (Generalized Orientation-Dependent, All-atom Statistical Potential) score, which we found to perform better than other commonly used functions, such as Molprobity and the correlation coefficient from refinement. Finally, we describe the efficacy of this protocol in retrieving appropriate pixel sizes for several examples; simulated data based on yeast elongation factor 2, and experimental data from Gro-EL chaperone, beta-galactosidase and the TRPV1 ion channel.