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Ahmed FT, Khan AHAN, Khan R, Saha SK, Alam MF, Dafader NC, Sultana S, Elius IB, Mamum SA. Characterization of arsenic contaminated groundwater from central Bangladesh: Irrigation feasibility and preliminary health risks assessment. ACTA ACUST UNITED AC 2021. [DOI: 10.1016/j.enmm.2021.100433] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Li J, Hu M, Scaffidi MA, Gimpaya N, Bansal R, Verma Y, Elsolh K, Khan R, Grover SC. A104 PREVALENCE OF GHOST-AUTHORSHIP IN INDUSTRY-SPONSORED CLINICAL TRIALS. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Ghost-authorship involves the exclusion of individuals who have made substantial contributions to the article from the author byline. Previous studies have found that ghost-authorship is highly prevalent in industry-sponsored clinical trials. Its prevalence, however, has yet to be investigated in trials of biologics in the management of inflammatory bowel disease (IBD).
Aims
To determine the prevalence of ghost-authorship in IBD biologic industry-sponsored clinical randomized controlled trials (RCTs).
Methods
Biologic medications indicated for ulcerative colitis (UC) or for Crohn’s disease (CD) were identified using the Food and Drug Agency (FDA) database. We identified the clinical trials on clinicaltrials.gov corresponding to the data presented at the time of FDA approval. Specifically, we included the first publication for each trial to report study results for our analysis. Two authors independently identified the presence of ghost-authorship, which we defined as the exclusion on the author byline of the included RCT publication of any individuals who assisted in the writing of the trial manuscript and/or performed the data analyses.
Results
We identified a total of 28 relevant RCTs on biologic medications (10 for UC and 18 for CD), which were matched to 20 publications. We found ghost-authorship in 70% of publications (n=14); 40% (n=8) involved manuscript and protocol writing assistance from sponsor staff; 35% (n=7) involved medical writers from external companies; 15% (n=3) involved both sponsor staff and medical writers assisting in manuscript writing; and 20% (n=4) involved individuals performing data analysis or interpretation.
Conclusions
We found that ghost-authorship in industry-sponsored IBD biologic clinical trials has a moderately high prevalence, with the most common being manuscript or protocol writing assistance. A lack of transparency regarding sponsor-affiliated and/or external contributors may negatively affect the trust placed in medical research. One limitation is that data was only extracted from publications. Further evidence on ghost-authorship may be found in study protocols and registrations, which will be investigated in the future.
Funding Agencies
None
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Khan R, Zheng E, Wani SB, Scaffidi MA, Jeyalingam T, Gimpaya N, Anderson J, Grover SC, McCreath G, Walsh CM. A97 TOOLS FOR DIRECT OBSERVATION AND ASSESSMENT OF COLONOSCOPY: A SYSTEMATIC REVIEW OF VALIDITY EVIDENCE. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
An increasing focus on quality and safety in colonoscopy has led to broader implementation of competency-based educational systems that enable documentation of trainees’ achievement of the knowledge, skills, and attitudes needed for independent practice. The meaningful assessment of competence in colonoscopy is critical to this process. While there are many published tools that assess competence in performing colonoscopy, there is a wide range of underlying validity evidence. Tools with strong evidence of validity are required to support feedback provision, optimize learner capabilities, and document competence.
Aims
We aimed to evaluate the strength of validity evidence that supports available colonoscopy direct observation assessment tools using the unified framework of validity.
Methods
We systematically searched five databases for studies investigating colonoscopy direct observation assessment tools from inception until April 8, 2020. We extracted data outlining validity evidence from the five sources (content, response process, internal structure, relations to other variables, and consequences) and graded the degree of evidence, with a maximum score of 15. We assessed educational utility using an Accreditation Council for Graduate Medical Education framework and methodological quality using the Medical Education Research Quality Instrument (MERSQI).
Results
From 10,841 records, we identified 27 studies representing 13 assessment tools (10 adult, 2 pediatric, 1 both). All tools assessed technical skills, while 10 assessed cognitive and integrative skills. Validity evidence scores ranged from 1–15. The Assessment of Competency in Endoscopy (ACE) tool, the Direct Observation of Procedural Skills (DOPS) tool, and the Gastrointestinal Endoscopy Competency Assessment Tool (GiECAT) had the strongest validity evidence, with scores of 13, 15, and 14, respectively. Most tools were easy to use and interpret and required minimal resources. MERSQI scores ranged from 9.5–11.5 (maximum score 14.5).
Conclusions
The ACE, DOPS, and GiECAT have strong validity evidence compared to other assessments. Future studies should identify barriers to widespread implementation and report on use of these tools in credentialing purposes.
Funding Agencies
None
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Bansal R, Khan R, Gimpaya N, Scaffidi MA, Elsolh K, Verma Y, Li J, Grover SC. A160 PREVALENCE OF OUTCOME SWITCHING AMONG PUBLISHED PHASE 3 INTERVENTIONAL TRIALS FOR INFLAMMATORY BOWEL DISEASE THERAPEUTICS. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Outcome switching is a well-described form of inconsistent reporting in randomized clinical trials (RCTs), wherein pre-specified primary and/or secondary outcomes are changed between trial registration and the publication of results without explanation. This is of particular concern, as the selective publication of results that are favorable will insert bias into the trial’s results and may cast doubt on the veracity of its findings. While it has been investigated in other disciplines, the prevalence of outcome switching has yet to be described among RCTs for inflammatory bowel disease (IBD).
Aims
To determine the prevalence of correctly reported pre-specified primary and secondary outcomes in published phase 3 interventional RCTs for IBD.
Methods
We identified all phase 3 interventional trials for IBD with published results using clinicaltrials.gov. We included all results with an associated publication that detailed the results of the trial. We excluded registrations if: only an abstract of the results was available; trial results were only published as a pooled analysis; multiple trial segments were reported collectively; or a publication of the results could not be identified through clinicaltrials.gov or a custom search.
Two reviewers extracted all pre-specified primary and secondary outcomes for each trial using the clinical trial registration page that was dated before the commencement of the trial. These outcomes were compared to the outcomes reported in the corresponding journal articles. Any discrepancies were noted, and additional outcomes were extracted.
Results
We identified a total of 88 phase 3 interventional RCTs for IBD, of which 57 were matched to independent publications of their results. All trials pre-specified a primary outcome, and 50 (87.7%) pre-specified secondary outcomes. 10 (17.5%) of trials did not report some or all primary outcomes, and 19 (33.3%) trials had a change or alteration to the primary outcome. Of the trials that pre-specified secondary outcomes, 16 (28.1%) did not report all pre-specified secondary outcomes. 49 (86.0%) trials added 6 (IQR: 2–8) unspecified secondary outcomes on average.
Conclusions
Many phase 3 interventional RCTs in IBD either did not report some or all primary outcomes, or altered the primary outcome. Trials routinely reported additional outcomes that were not pre-specified and failed to note that they were added post hoc. Based on these results, we recommend improvements in the reporting of pre-specified outcomes and higher fidelity in order to maintain confidence in trial results.
Funding Agencies
None
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Verma Y, Scaffidi MA, Gimpaya N, Panjwani A, Bansal R, Li J, Elsolh K, Khan R, Grover SC. A70 PREVALENCE OF SELF-PUBLICATION AMONG EDITORIAL BOARD MEMBERS OF GASTROENTEROLOGY JOURNALS. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Editorial self-publication refers to the practice wherein editors publish research in journals to which they serve as editorial board members. The International Committee of Medical Journal Editors (ICMJE) has detailed recommendations against the practice of self-publication. There is evidence to suggest that editorial board membership may influence the decision to publish academic papers, which may contribute to publication bias. Despite this, there have been few attempts to characterize this practice in gastroenterology journals.
Aims
To determine the prevalence of original gastroenterology research articles published by editorial board members in their own journal.
Methods
We conducted a cross-sectional study to determine the prevalence of editorial board members publishing within their own journals. A list of the top 25 highest impact factor gastroenterology journals was created through InCites Journal reports. Journals were screened to determine eligibility based on whether their primary focus included gastroenterology research and whether archives with the names and affiliations of editorial board members were available. 10 journals were selected based on these criteria. For each journal, we extracted all original research articles published in 2019 using Web of Science (Clarivate Analytics ©). Articles classified as editorial material, meeting abstracts, reviews, and clinical practice guidelines were excluded. We cross-referenced the affiliations of all authors found in each publication with affiliations of editors disclosed on the journal website. For each editorial board member, we determined the number of publications within their own journal.
Results
We identified 844 editorial board members in the 10 journals included. Overall, 337 (39.9%) of the editors had a publication in their own journal, of which, 152 (18.0%) had more than one publication. Across all journals, the median number of editors with self-publication is 27 (IQR=20.3–49.8). The median number of editors with more than one self-publication is 16 (IQR=10.0–25.3). In total, 507 (60.1%) of all editors had no publications within their respective journals.
Conclusions
Despite recommendations against this practice, our results show a high number of research publications authored by editorial board members. These results demonstrate a potential risk for publication bias. However, this study was limited by the inability to investigate beyond the prevalence of self-publication. Furthermore, the explicit implications of our results remain unclear. Further research is required to evaluate factors such as disclosures and the review process associated with increased rates of self-publication as well as its impact on publication bias.
Funding Agencies
None
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Khan R, Elsolh K, Gimpaya N, Scaffidi MA, Bansal R, Grover SC. A89 CHARACTERISTICS AND CONFLICTS OF INTEREST AT FOOD AND DRUG ADMINISTRATION GASTROINTESTINAL DRUG ADVISORY COMMITTEE MEETINGS. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The United States Food and Drug Administration (FDA) Gastrointestinal Drug Advisory Committee (GIDAC) is involved in gastrointestinal drug application reviews. Characteristics and conflicts of interest (COI) in GIDAC meetings are not well described.
Aims
To analyze FDA GIDAC meetings and characteristics that predict recommendations.
Methods
This was a cross-sectional study of all publicly available GIDAC meetings where proposed medications were voted on from 1998–2018. Data were collected on individual meetings and individual voting members at meetings. Predefined predictor variables included type of medication, medication sponsor, primary efficacy studies, and voting member characteristics (e.g. committee membership, COI). Univariate analyses were conducted at per-meeting and per-vote levels to assess for predictors of committee recommendation and individual votes respectively.
Results
Thirty-four meetings with 476 individual votes from 1998–2018 were included. Twenty-three (68%) proposals were recommended for approval and 25 (74%) received FDA approval. Most proposals involved >1 primary study (n=27, 79%). At least one voting member had a COI in 24 (71%) of 34 meetings. Twelve (35%) meetings had at least one sponsor COI. Among 476 individual votes, 74 (15.5%) involved a COI, with 33 (6.9%) sponsor COI. COI decreased significantly over time, with more COI in 1996–2000 and 2001–2005 compared to 2006–2010, 2011–2015, and 2016–2020 (p<0.01). There were no significant associations between pre-defined predictors, including COI, and committee level recommendations or individual votes (p>0.05 for all univariate analyses).
Conclusions
The GIDAC reviewed 34 proposals from 1998–2018. The majority were recommended for approval and later approved by the FDA, highlighting the GIDAC’s prominence in the regulatory process. COI are present among GIDAC panelists but decreasing over time and not associated with recommendations.
Funding Agencies
None
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Gimpaya N, Khan R, Gallinger ZR, Scaffidi MA, Al Abdulqader AK, Ahmed M, Gholami R, Ramkissoon A, James PD, Mosko J, Griller N, Bansal R, Grover SC. A77 A REUSABLE POLYCARBONATE BOX TO DECREASE DROPLET CONTAMINATION DURING UPPER ENDOSCOPY: A SIMULATION-BASED STUDY FOR THE COVID-19 PANDEMIC. J Can Assoc Gastroenterol 2021. [PMCID: PMC7989228 DOI: 10.1093/jcag/gwab002.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Upper gastrointestinal (GI) endoscopic procedures are aerosol-generating, increasing the risk of healthcare workers (HCW) contracting Coronavirus disease 2019 (COVID-19). Aims To present a polycarbonate box (EndoBox) designed for use in upper GI endoscopy and evaluate its impact on the contamination of endoscopy staff during simulated procedures. Methods Simulated gastroscopies were performed using an upper body simulator placed in left lateral decubitus (LLD) and supine positions. The endoscopist and assistant wore personal protective equipment. Droplet exposure was measured using fluorescent abiotic surrogate particles. Two blinded observers independently viewed images from each scenario to qualitatively evaluate contamination levels. The primary outcome was the level of HCW contamination by droplets generated from a simulated cough with and without the EndoBox on the upper body simulator. The endoscopist’s ergonomic behaviour was also assessed using the Rapid Upper Limb Assessment (RULA) tool. Results Without the EndoBox, there was a higher level of contamination on the endoscopist when the upper body simulator is in the LLD position. A higher level of contamination was observed on the assistant when the simulator is in supine position. With the EndoBox, the contamination levels on the endoscopy staff were lower in both LLD and supine scenarios. The endoscopist’s ergonomics were rated 2 to 3 on the RULA tool when using the EndoBox. Conclusions The EndoBox reduces macroscopic droplet contamination during simulated gastroscopy. The endoscopist’s risk of musculoskeletal injury remained in the low risk categories as assessed by the RULA tool. Another advantage of the EndoBox design is the arch extending from the bottom that allows for removal of the box without withdrawing the endoscope. This enables rapid access to the patient’s airway if they experience respiratory distress. This study was limited by an inability to assess microscopic contamination and contamination at the level of the port or buttons when suction is applied. Within these limitations, the EndoBox may be a useful adjunct to traditional personal protective equipment. Funding Agencies SMHA AFP COVID-Related Innovation Funds
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Elsolh K, Tham D, Scaffidi MA, Bansal R, Li J, Verma Y, Gimpaya N, Khan R, Grover SC. A161 PREVALENCE OF FINANCIAL CONFLICTS OF INTEREST (FCOI) AMONG PROPENSITY-SCORE MATCHED RETROSPECTIVE STUDIES EVALUATING BIOLOGIC THERAPEUTICS FOR IBD. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Inflammatory Bowel Disease (IBD) studies have commonly relied on real-world evidence to evaluate different therapies. An emerging idea has been the use of propensity score matching as a statistical method to account for baseline characteristics in IBD patients. In retrospective studies, propensity score matching of patients helps reduce treatment assignment bias and mimic the effects of randomization. Recently, propensity-score matching has become an important tool in IBD studies comparing biologic therapeutics. Biologic medications are among the highest-grossing drugs worldwide, and their pharmaceutical producers make considerable payments to physicians to market them. In spite of this, there is a lack of evidence examining the role of undue industry influence among propensity-score matched comparative studies evaluating biologic therapeutics for IBD.
Aims
Given the documented association between IBD biologics and FCOI, we hypothesize a high burden of FCOI in propensity-score matched studies. The aim of this study was to evaluate the prevalence of disclosed & undisclosed financial conflicts of Interest (FCOI) in propensity-score matched comparison studies evaluating biologics for IBD.
Methods
We developed & ran a librarian-reviewed systematic search on EMBASE, MEDLINE, and Cochrane Library databases for all propensity-score matched retrospective studies comparing biologics for the treatment of IBD. Full-text retrieval & screening was performed on all studies in duplicate. 16 articles were identified. Industry payments to authors were only considered FCOI if they were made by a company producing a biologic that was included in the comparison study. Disclosed FCOI were identified by authors’ interests disclosures in full-texts. Any undisclosed FCOI among US authors were identified using the Centre for Medicare and Medicaid Services (CMS) Open Payments Database, which collects industry payments to physicians.
Results
Based on a preliminary analysis of 16 studies, there was at least one author with a relevant FCOI in 14 (88%) of the 16 studies. 14 studies (88%) had at least one disclosed FCOI, while 6 studies (37.5%) had at least one undisclosed FCOI. Among studies with disclosed FCOI, a mean of 40.2% (SD = 23.4%) of authors/study reported FCOI. Among studies with undisclosed FCOI, a mean of 18.8% (SD = 7.0%) of authors/study reported FCOI. The total dollar value of FCOIs was $1,974,328.3. The median conflict dollar value was $5,576.6 (IQR: $321.6 to $36,394.9).
Conclusions
We found a high burden of undisclosed FCOI (37.5%) among authors of propensity-score matched studies evaluating IBD biologics. Given the potential for undue industry influence stemming from such payments, authors should ensure better transparency with industry relationships.
Funding Agencies
None
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Gholami R, Gimpaya N, Khan R, Scaffidi MA, Bansal R, Ramkissoon A, Alabdulqader A, Grover SC. A71 RECOMMENDATION REVERSALS IN GASTROENTEROLOGY CLINICAL PRACTICE GUIDELINES. J Can Assoc Gastroenterol 2021. [DOI: 10.1093/jcag/gwab002.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Clinical practice guidelines are evidence-based resources designed to inform clinical decision making. Often, superior evidence will support the inclusion of novel procedures and practices to replace older recommendations. Recommendation reversals occur when (a) superior quality evidence emerges to suggest the harm or non-beneficence of prior recommendations, and (b) that recommendation is not supplanted by a newer one.
Aims
The primary objective of this study was to describe the content, frequency and rationale for recommendation reversals in CPGs published by gastroenterological societies.
Methods
For this meta-epidemiologic study, we considered two criteria to define a recommendation reversal: (a) the more recent CPG makes a recommendation that contradicts a previously accepted practice; and (b) the prior recommendation is not replaced by any novel intervention. We searched CPGs published by 20 major GI societies from 1991- 2019. Guidelines were included if had at least two iterations with the same title and used a valid evidence rating system (such as GRADE). Explicit recommendations which reported definite levels of evidence and strength of recommendation were extracted.
Results
We identified 1022 clinical guidelines from GI societies over 28 years. 292 CPGs were included for data synthesis. 5985 explicit statements were extracted. 12 reversals were confirmed and are summarized in the Table. Six reversals (50.0%) occurred due to studies reporting non-beneficence and 3 (25.0%) occrred due to studies reporting harm. Three recommendations (25.0%) were reversed due to new clinical trials; 3 (25.0%) due to systematic reviews or meta-analyses; and 2 to conform with CPGs of other societies (16.7%).
Conclusions
We describe recommendation reversals made in gastroenterology CPGs, and the reasons thereof. Investigation of recommendation reversals allows for the identification of low-value medical practices. This reinforces the need for GI CPG committees to (1) iteratively review guidelines to re-evaluate recommendations made on low-quality evidence and; (2) refrain from making recommendations when evidence for the same is weak.
Funding Agencies
None
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Khan R, Islam HMT, Islam ARMT. Mechanism of elevated radioactivity in Teesta river basin from Bangladesh: Radiochemical characterization, provenance and associated hazards. CHEMOSPHERE 2021; 264:128459. [PMID: 33032211 DOI: 10.1016/j.chemosphere.2020.128459] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/14/2020] [Accepted: 09/27/2020] [Indexed: 06/11/2023]
Abstract
This work presents a river basin (Teesta River, Bangladesh) which possesses significantly higher radioactivity compared to other freshwater basins around the globe. A total of thirty sediment samples were collected to determine the naturally occurring radionuclides (226Ra, 232Th, and 4 K)and elemental abundances using the HPGe gamma spectrometry and instrumental neutron activation analysis (INAA), respectively. To understand the provenance of higher radioactivity, the compositional elements (Sc, Ti, V, Fe, La, Ce, Sm, Eu, Dy, Yb, Lu, Hf, Ta, Th, and U) of heavy minerals are thoroughly studied, where ∑REEs (rare earth elements), Hf, Ta, Th, and U are ∼2 times higher than the crustal values with negative Ce and Eu anomalies. Mechanism to co-occurrence among radioactivity concentrations and REEs has been explored in this work. Enrichment of light rare earth elements ( × 2.01 UCC) and thorium ( × 2.8 UCC), and Th/U (=5.54 ± 1.05), 232Th/4 K ratio and statistical analyses demonstrate the presence of heavy minerals with monazite predominance. Accumulations of these minerals are most likely due to the fluvial suspended sediments transported by the hydrodynamic forces from up-stream. Elemental ratios including La/V, Th/Yb, Th/Sc, and Hf/Sc confirm the dominance of felsic-source over the mafic-components and the source of sediment has experienced major recycling and sorting during transportation. Evaluation of radiological risks invokes ionizing radiation related hazards to the local inhabitants and the householders residing in the buildings comprised with sandy river sediments. However, minute probability of REEs, Th, and U entrance to the human body through food chain can cause trivial health risks.
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Khan R, Naz I, Hussain S, Khan RAA, Ullah S, Rashid MU, Siddique I. Phytochemical management of root knot nematode (Meloidogyne incognita) kofoid and white chitwood by Artemisia spp. in tomato (Lycopersicon esculentum L.). BRAZ J BIOL 2020; 80:829-838. [PMID: 31800766 DOI: 10.1590/1519-6984.222040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 08/12/2019] [Indexed: 12/26/2022] Open
Abstract
In vitro and screen house experiments were conducted to investigate the effectiveness of thirteen phytochemicals from Artemisia elegantissimia and A. incisa on root knot nematode, Meloidogyne incognita in tomato (Lycopersicon esculentum L.) cv. Rio Grande. A positive control (Carbofuran) and negative control (H2O) were also used for comparison. Effectiveness of phytochemicals against juveniles (J2s) mortality and egg hatch inhibition were evaluated after 24, 48 and 72 hours of incubation at three concentrations viz; 0.1, 0.2 and 0.3 mg/mL in vitro conditions. Amongst thirteen phytochemicals, Isoscopletin (Coumarin), Carbofuran and Apigenin (Flavonoid) showed the highest mortality and egg hatch inhibition of M. incognita at all intervals. Inhibition of eggs and J2s mortality were the greatest (90.0%) and (96.0%) at 0.3 mg/mL concentration. Application of phytochemicals caused reduction in number of galls, galling index, and egg masses on tomato plant and enhanced plant growth parameters under screen house conditions. Gall numbers (1.50), galling index (1.00), number of juveniles (4.83) and egg masses (4.00) were greatly reduced and plant growth parameters such as; plant height (28.48 cm), fresh (72.13 g) and dry shoot weights (35.99 g), and root fresh (6.58 g) and dry weights (1.43 g) were increased significantly by using Isoscopletin. In structure activity relationship, juveniles of M. incognita, exhibited variations in their shape and postures upon death when exposed to different concentrations of phytochemicals of Artemisia spp. The present study suggests that Artemisia based phytochemicals possess strong nematicidal effects and can be used effectively in an integrated disease management program against root knot nematodes.
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Srivastava AK, Dwivedi N, Dhand C, Khan R, Sathish N, Gupta MK, Kumar R, Kumar S. Potential of graphene-based materials to combat COVID-19: properties, perspectives, and prospects. MATERIALS TODAY. CHEMISTRY 2020; 18:100385. [PMID: 33106780 PMCID: PMC7577689 DOI: 10.1016/j.mtchem.2020.100385] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/18/2020] [Accepted: 10/16/2020] [Indexed: 05/19/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new virus in the coronavirus family that causes coronavirus disease (COVID-19), emerges as a big threat to the human race. To date, there is no medicine and vaccine available for COVID-19 treatment. While the development of medicines and vaccines are essentially and urgently required, what is also extremely important is the repurposing of smart materials to design effective systems for combating COVID-19. Graphene and graphene-related materials (GRMs) exhibit extraordinary physicochemical, electrical, optical, antiviral, antimicrobial, and other fascinating properties that warrant them as potential candidates for designing and development of high-performance components and devices required for COVID-19 pandemic and other futuristic calamities. In this article, we discuss the potential of graphene and GRMs for healthcare applications and how they may contribute to fighting against COVID-19.
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Islam MA, Das B, Quraishi SB, Khan R, Naher K, Hossain SM, Karmaker S, Latif SA, Hossen MB. Heavy metal contamination and ecological risk assessment in water and sediments of the Halda river, Bangladesh: A natural fish breeding ground. MARINE POLLUTION BULLETIN 2020; 160:111649. [PMID: 33181930 DOI: 10.1016/j.marpolbul.2020.111649] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/25/2020] [Accepted: 09/05/2020] [Indexed: 05/24/2023]
Abstract
This study reports the mass fractions of Al, Cr, Mn, Fe, Co, Zn, As, Ni, Cu, Cd, Hg, and Pb in water and sediments of the Halda river, Bangladesh, and studies the distribution, contamination, and potential ecological risks of the metals and metalloid. The average mass fractions of As, Cd, and Pb are relatively higher in sediments compared to those in background values, whereas Al, Fe, Mn, and Pb concentration fractions in water are higher than the international guideline values. The results of the different contamination indices indicate that Halda river sediments are minorly contaminated by As and Pb and moderately to considerably contaminated by Cd. The ecological risk assessments indicate considerable to high ecological risk due to Cd. Multivariate statistical analysis reveals the origin of the contaminants in the river, and indicate that Cr, Zn, Pb, and Cd are from anthropogenic activities while the other metals originate from natural lithogenic actions.
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Ikomi A, Mannan S, Simon G, Khan R, Smith S, Robbins J, Kavanagh U, Crone D. Diagnosis of gestational diabetes during the pandemic: what is the risk of falling through the net? Diabet Med 2020; 37:1782-1784. [PMID: 32585723 PMCID: PMC7362157 DOI: 10.1111/dme.14346] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/18/2020] [Indexed: 12/26/2022]
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Towfiqul Islam ARM, Hasanuzzaman M, Touhidul Islam HM, Mia MU, Khan R, Habib MA, Rahman MM, Siddique MAB, Moniruzzaman M, Rashid MB. Quantifying Source Apportionment, Co-occurrence, and Ecotoxicological Risk of Metals from Upstream, Lower Midstream, and Downstream River Segments, Bangladesh. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2020; 39:2041-2054. [PMID: 32633828 DOI: 10.1002/etc.4814] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/10/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
The positive matrix factorization (PMF) receptor model was used for the first time to quantify the source contributions to heavy metal pollution of sediment on a national basin scale in the upstream, midstream, and downstream rivers (Teesta and Kortoya-Shitalakkah and Meghna-Rupsha and Pasur) of Bangladesh. The metal contamination status, co-occurrence, and ecotoxicological risk were also investigated. Sediment samples were collected from 30 sites at a depth range of 0 to 20 cm for analysis of 9 metals using inductively coupled plasma-mass spectrometry. The mean concentrations of metals varied for upstream, lower midstream, and downstream river segments. The results showed that chromium (Cr) exhibited a strong significant co-occurrence network with other metals (e.g., manganese [Mn], iron [Fe], and nickel [Ni]). Monte Carlo simulation results of the geo-accumulation index (Igeo; 63.3%) and risk indices (48.5%) showed that cadmium (Cd) was the main contributor to sediment pollution. However, the cumulative probabilities of sediments being polluted by metals were ranked as "moderate to heavily polluted" (Igeo 46.6%; risk index 16.7%). Toxicity unit results revealed that zinc (Zn) and Cd were the key toxic contributors to sediments. The PMF model predicted metal concentrations and identified 4 potential sources. The agricultural source (factor 1) mostly contributed to copper (Cu; 78.9%) and arsenic (As; 62.8%); Ni (96.9%) and Mn (83.5%) exhibited industrial point sources (factor 2), with 2 hot spots in northwestern and southwestern regions. Cadmium (93.5%) had anthropogenic point sources (factor 3), and Fe (64.3%) and Cr (53.5%) had a mixed source (factor 4). Spatially, similar patterns between PMF apportioning factors and predicted metal sources were identified, showing the efficiency of the model for river systems analysis. The degree of metal contamination in the river segments suggests an alarming condition for biotic components of the ecosystem. Environ Toxicol Chem 2020;39:2041-2054. © 2020 SETAC.
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Islam ARMT, Islam HMT, Mia MU, Khan R, Habib MA, Bodrud-Doza M, Siddique MAB, Chu R. Co-distribution, possible origins, status and potential health risk of trace elements in surface water sources from six major river basins, Bangladesh. CHEMOSPHERE 2020; 249:126180. [PMID: 32086063 DOI: 10.1016/j.chemosphere.2020.126180] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 02/05/2020] [Accepted: 02/10/2020] [Indexed: 05/24/2023]
Abstract
In this study, we appraised the concentrations of 8 major trace elements (TEs) in surface water sources from six river basins, Bangladesh: Meghna, Kartoya, Sitalakha, Teesta, Pashur and Rupsha River basins. Co-distribution, the status of water quality and potential health risks were assessed using statistical analyses, the entropy water quality index (EWQI), sodium adsorption ratio (SAR), spatial autocorrelation index (SAI), hazard index (HI), and Monte-Carlo (MC) simulation. The spatial variations of TEs concentrations differed notably among the studied river basins. The average concentrations of TEs (except Ni, As, and Zn) in six river basins exceeded the drinking water quality guidelines. About 20% of water samples in six basins were categorized as undrinkable to poor qualities for drinking uses, while good water quality for irrigation purposes. The entropy theory identified that Cr, Pb, and As are the key pollutants influencing the water quality. According to the results of non-carcinogenic risk, the hazard index (HI) values for adults and children surpassed the allowable limit (>1), demonstrating detrimental health effects on humans. The carcinogenic risk values of chromium (Cr) were much higher than As and Cd exposures which exceeded the benchmark recommended by US EPA (>10-6 to 10-4), with an elevated risk for adults than children through the oral intake as the primary exposure route. Overall, the results suggest that the local population exposed to surface water may pose an adverse health effect, thus, strict regulation and efficient management should be focused on Cr, Cd and As monitoring and appraisal in these basins.
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Khan M, Khalid MH, Kamran M, Khan R. Symplectic Computations of Fast Ion Trajectory and Radial Diffusion Coefficient in MHD Perturbed Tokamak. JOURNAL OF FUSION ENERGY 2020. [DOI: 10.1007/s10894-020-00236-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Ismail II, Abokalawa FM, Kamel W, Khan R, Al-Hashel JY. Association of Ramadan Fasting and Clinical Outcomes in Patients With Myasthenia Gravis. JAMA Netw Open 2020; 3:e204373. [PMID: 32324235 PMCID: PMC7180419 DOI: 10.1001/jamanetworkopen.2020.4373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This cohort study examines the association of Ramadan fasting with clinical outcomes in patients with myasthenia gravis.
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Uddin AKMR, Siddique MAB, Rahman F, Ullah AKMA, Khan R. Cocos nucifera Leaf Extract Mediated Green Synthesis of Silver Nanoparticles for Enhanced Antibacterial Activity. J Inorg Organomet Polym Mater 2020. [DOI: 10.1007/s10904-020-01506-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Habib MA, Islam ARMT, Bodrud-Doza M, Mukta FA, Khan R, Bakar Siddique MA, Phoungthong K, Techato K. Simultaneous appraisals of pathway and probable health risk associated with trace metals contamination in groundwater from Barapukuria coal basin, Bangladesh. CHEMOSPHERE 2020; 242:125183. [PMID: 31675577 DOI: 10.1016/j.chemosphere.2019.125183] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 10/06/2019] [Accepted: 10/20/2019] [Indexed: 05/24/2023]
Abstract
In this study, we analyzed 33 groundwater samples from the Barapukuria coal basin (BCB), Bangladesh for 10 trace metals (TMs) using Atomic Absorption Spectroscopy. Pathways and associated probable health risk were appraised by employing multivariate statistical approaches, health risk model and Monte-Carlo simulation. Except for the Cu, Cr and Zn concentrations, the mean concentrations of all TMs in the basin were above the permissible water quality limits set by Bangladesh and international standards. Correlation coefficient and principal component analysis, supported by cluster analysis indicated that anthropogenic inputs were more contributed to the elevated concentrations of TMs compared to geogenic sources as the major reasons of groundwater pollution in the basin. The results of non-carcinogenic risk appraisal depicted that hazard index (HI) values for both adults and children were exceeded the safe limits (>1.0) except for few locations, indicating serious health risks on the human via oral and dermal absorption pathways. However, the carcinogenic risk values of Cd and Cr exceeded the US EPA range of 1 × 10-6 to 1 × 10-4, with higher risk for children than adults, with oral intake as the key exposure pathway. A sensitivity study identified the concentration of Cr, exposure frequency and ingestion rate for carcinogenic effect as the most sensitive parameters influencing the probable health risk. Overall, the results suggest that Cr in drinking water could cause detrimental effects to exposed local residents; thus, strict health regulation and groundwater management should concentrate on Cr contamination in groundwater from the coal basin.
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Nazarian A, Bishay K, Gholami R, Scaffidi MA, Khan R, Cohen-Lyons D, Griller N, Satchwell JB, Baker J, Irvine EJ, Grover SC. A243 FACTORS ASSOCIATED WITH POOR QUALITY OF LIFE IN PATIENTS WITH INFLAMMATORY BOWEL DISEASE IN CLINICAL REMISSION: A CROSS-SECTIONAL STUDY. J Can Assoc Gastroenterol 2020. [DOI: 10.1093/jcag/gwz047.242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Inflammatory bowel disease (IBD) is associated with a substantial burden on quality of life (QoL). Functional gastrointestinal disorders such as irritable bowel syndrome (IBS) as well as depression and anxiety are more common in patients with IBD as compared with the general population. Although poorer QoL is correlated with IBS, depression and anxiety in individuals with IBD at times of IBD diagnosis and disease activity, it is unclear what, if any, impact these may have on overall quality of life at times of disease remission.
Aims
We aimed to identify factors associated with poor QoL among Canadian patients with IBD in clinical remission.
Methods
We conducted a prospective, cross-sectional study to determine whether fatigue, depression, anxiety and IBS were associated with lower QoL in patients with IBD in clinical remission. We enrolled patients at a single academic tertiary care center with inactive IBD. All eligible patients completed a series of questionnaires that included questions on demographics, disease activity, anxiety, depression, and the presence of irritable bowel syndrome (IBS) symptoms. Stool samples for fecal calprotectin (FC) were also collected to assess for subclinical inflammation. The primary outcome measure was QoL assessed by the short inflammatory bowel disease questionnaire (SIBDQ), with planned subgroup comparisons for fatigue, anxiety, depression and IBS symptoms.
Results
Ninety-three patients were eligible for inclusion in this study. The median SIBDQ scores were lower in patients with anxiety (P<0.001), depression (P=0.004), IBS symptoms (P<0.001), and fatigue (P=0.018).
Conclusions
In this cross-sectional study, we found that anxiety, depression, fatigue, and IBS-like symptoms were all independently associated with lower QoL among patients with inactive IBD. Importantly, subclinical inflammation as defined by a positive fecal calprotectin in the absence of clinical symptoms did not have an adverse effect on QoL. The findings of this study suggest that patients with IBD would likely benefit from screening for depression, anxiety, fatigue and IBS. Further research is warranted to determine if targeted treatment of these conditions, specifically in patients with quiescent IBD would lead to improved outcomes.
Funding Agencies
None
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Khan R, Scaffidi MA, Gimpaya N, Tham D, Atalla M, Al-Mazroui A, Gholami R, Satchwell JB, Walsh CM, Grover SC. A143 IMPACT OF A SIMULATION-BASED AUGMENTED REALITY CURRICULUM ON POLYPECTOMY SKILLS AMONG NOVICE ENDOSCOPISTS: A RANDOMIZED CONTROLLED TRIAL. J Can Assoc Gastroenterol 2020. [DOI: 10.1093/jcag/gwz047.142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Polypectomy is an essential endoscopic skill. Training in polypectomy has been identified as a major deficiency for endoscopists worldwide as polypectomy occurs ad hoc during a colonoscopy when a polyp is detected, and a lack of standardized curricula. Augmented reality (AR), which superimposes computer-generated images on a user’s view of the world, can address these gaps by standardizing encounters with polyps while completing simulated procedures and enabling polypectomy-specific teaching.
Aims
Evaluate the impact of a simulation-based augmented reality curriculum on polypectomy performance among novice endoscopists.
Methods
This study includes two cohorts of participants from 2019 to 2020. In 2019, participants were randomized into either: (1) a control curriculum, involving 6 hours of simulation-based training (SBT) supplemented by expert feedback, interlaced with 4 hours of small group teaching on the theory of colonoscopy; or (2) the augmented reality curriculum (ARC), in involving the same curriculum with integrated AR, wherein participants engaged with an AR-enhanced video demonstrating relevant therapeutic and pathologic details during polypectomy. The SBT for all participants involved a progressive curriculum starting on a bench-top model and then moving to the EndoVR® virtual reality simulator. The primary outcome was polypectomy-specific performance using the Direct Observation of Polypectomy Skills (DOPyS) tool during a simulated polypectomy after training, with a maximum score of 100.
Results
Demographic characteristics are summarized in Table. In 2019, 21 novice endoscopists were enrolled. Immediately after training, the mean DOPyS score among ARC group participants was 76.2 (SD=17.9) compared to 71.8 (SD=13.2) among control group participants (Figure). In this interim analysis, there was no significant difference between groups. Data analysis will be completed after 2020 participants complete the study.
Conclusions
Interim results show a trend towards improved polypectomy performance with no significant difference. The results of this study have the potential to impact polypectomy education among novices. Simulation-based AR interventions may allow learners to progress towards achieving competency in polypectomy in a risk-free environment prior to first patient contact.
Funding Agencies
None
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Khan R, Satyapal K, Lazarus L, Naidoo N. An anthropometric evaluation of the scapula, with emphasis on the coracoid process and glenoid fossa in a South African population. Heliyon 2020; 6:e03107. [PMID: 31909271 PMCID: PMC6938878 DOI: 10.1016/j.heliyon.2019.e03107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/29/2019] [Accepted: 12/19/2019] [Indexed: 12/04/2022] Open
Abstract
The exact dimensions of the scapula, including the coracoid process and glenoid fossa, are fundamental in the patho-mechanics of the glenohumeral joint (GHJ); as these structures act as initiators of shoulder movement. The aim of the study was to evaluate the anthropometric parameters of the GHJ, with emphasis on the coracoid process and glenoid fossa. The morphometric (Linear Tools 2012, 0-150mm, LIN 86500963) and morphological parameters of a total of one hundred and sixty-four (n = 164) dry bone scapulae [Right (R): 80; Left (L): 84, Male (M): 68; Female (F): 96] were recorded. Results: (i) Shape of glenoid fossa: Type 1: (R) 16.5%, (L) 11.0%; Male (M) 20.1%, Female (F) 7.3%; Type 2: (R) 14.0%, (L) 15.2%; (M) 18.3%, (F) 11.0%; Type 3: (R) 18.3%, (L) 25.0%; (M) 27.4%, (F) 15.9%. (ii) Notch type: Type 1: (R) 1.7%, (L) 7.3%; (M) 6.7%, (F) 2.4%; Type 2: (R) 47.0%, (L) 43.9%; (M) 59.2%, (F) 31.7%. (iii) Vertical diameter of glenoid fossa (VD) (mm): (R) 35.2 ± 3.1, (L) 34.9 ± 3.0; (M) 35.3 ± 3.2, (F) 34.6 ± 2.8. (iv) Horizontal diameter 1 (HD1) of glenoid fossa (mm): (R) 18.4 ± 3.3, (L) 17.5 ± 2.9; (M) 18.2 ± 3.3, (F) 17.4 ± 2.6. (v) Horizontal diameter 2 (HD2) of glenoid fossa (mm): (R) 24.5 ± 2.9, (L) 23.6 ± 2.6; (M) 24.2 ± 2.7, (F) 23.7 ± 2.8. (vi) Length of coracoid process (CL) (mm): (R) 41.7 ± 4.7, (L) 41.5 ± 4.9; (M) 42.1 ± 4.7, (F) 40.7 ± 4.8. (vii) Width of coracoid process (CW) (mm): (R) 13.3 ± 1.9, (L) 14.2 ± 11.9; (M) 13.1 ± 1.9, (F) 15.1 ± 14.5. (viii) Coracoglenoid distance (CGD) (mm): (R) 27.4 ± 8.3, (L) 28.2 ± 3.5; (M) 28.2 ± 7.4, (F) 27.0 ± 3.4. In the present study, Type 3 (oval) was observed to be the predominant glenoid fossa shape with a higher incidence in male individuals and on the right side. Although only notch Types 1 (without a notch) and 2 (with one notch) were observed in this study, Type 2 (one notch) was the most prevalent, presenting with a significant p-value (p = 0.019), suggesting that notch Type 1 (without a notch) and 2 (with one notch) are common findings in the right and left side of individuals. The findings observed in this study may provide knowledge regarding the role of the coracoid parameters in etiology of subcoracoid impingement while knowledge on the glenoid fossa parameters and variations are essential for evaluation in shoulder arthroplasty for glenoid fractures and anterior dislocations, and for glenoid prosthesis designs for the South African population.
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Uddin MS, Rafee KA, Hossain SM, Khan R, Qaim SM. Integral measurement of spectrum-averaged cross sections of a few threshold reactions induced by fast neutrons of a TRIGA reactor: comparison with integrated data from excitation functions given in various data libraries. RADIOCHIM ACTA 2019. [DOI: 10.1515/ract-2019-3212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Integral cross sections of the reactions 24Mg(n,p)24Na, 27Al(n,p)27Mg, 27Al(n,α)24Na, 58Ni(n,d + np)57Co and 60Ni(n,p)60Co were measured for the first time using the fast neutron spectrum of a TRIGA reactor extending from 0.5 to 20 MeV. The values obtained in this work were comparable with the recommended values for a pure 235U prompt fission spectrum. The measured integral value was utilized for integral test of excitation function of each reaction given in some data libraries, namely ENDF/B-VIII.0, TENDL-2017, IRDFF-1.05 and ROSFOND-2010. The integral measurements are generally consistent with the integrated values within 5 %, except for a few cases, e. g. the reaction 60Ni(n,p)60Co, where the data libraries appear to need improvement.
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Tiwari B, Rajeswari PV, Ram S, Banerji P, Khan R. Green Synthesis of Cr 3+ Doped CaIn₂O₄-Carbon Hybrid Nanostructure and Its Light Absorption and Emission Properties. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2019; 19:8120-8125. [PMID: 31196334 DOI: 10.1166/jnn.2019.16865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this research article, we have used a novel route for synthesis of a greenish phosphor C-CaIn₂O₄ doped with Cr3+ ions using green plant (aloe vera gel) and measured its light absorption and emission properties. Our main aim was to enhance the light absorption and emission properties of undoped C-CaIn₂O₄ in order to widen its applications. The introduction of CrO₃ ions can produce Cr ion defects that favor charge balance in Cr3+:C-CaIn₂O₄ to facilitate its photoluminescence. The effect of doping in core-shell nanostructure can effectively transfer energy from charge-transfer absorption band of optical host material to characteristic transition of Cr3+ ions, utilizing more energy from host absorption for the photoluminescence of Cr3+ ions. As-prepared Cr3+:C-CaIn₂O₄ exhibits two bands at 270 nm and 370 nm, which are shifted to at 265 and 370 nm when it is annealed at higher dosage of Cr3+ ions. These are the ligand-to-metal O2- to Cr3+ charge transfer bands. The light-emission is studied in analyzing migration, transfer and recombination processes of light-induced e--h+ pairs. The results are described in correlation to a Cr3+:C-CaIn₂O₄ core-shell nanostructure.
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