12 research outputs found
Resonance in the Motion of a Geocentric Satellite due to Poynting-Robertson Drag
The problem of resonance in a geocentric Satellite under the combined gravitational forces of the Sun and the Earth due to Poynting-Robertson (P-R) drag has been discussed in this paper with the assumption that all three bodies, the Earth, the Sun and the Satellite, lie in an ecliptic plane. Our approach differs from conventional ones as we have placed evaluated velocity of the Satellite in equations of motion.We observed five resonance points commensurable between the mean motion of the Satellite and the average angular velocity of the Earth around the Sun, out of which two resonances occur only due to velocity dependent terms of P-R drag. Amplitudes and time periods are periodic with respect to the angle (angle between direction of vernal equinox and the direction of the Sun) which have been evaluated graphically in this paper.We have also found that amplitude as well as time-period decreases as orbital angle of the Earth around the Sun increases in the first quadrant
Application of “Travelling Salesman Problem” in Dynamic Programming for Efficient and Cost Effective Route Design for Distribution: Case of Chifles Distribution of ORFI Company, Ecuador
oai:ojs.pkp.sfu.ca:article/66Purpose: The present study is designed to optimize a route for the distribution of chifles of the ORFI Company in school bars within the Río Verde parish of the Santo Domingo City, Republic of Ecuador.
Methodology: Time and distance data were collected regarding the route of the vendors, then distance matrices were developed between distribution points, and a graph was designed to find the best route using the Bellman-Hell-Karp algorithm.
Results: The sector graph had 46 nodes and the optimal route was found by applying dynamic programming with the Held-Karp mathematical algorithm, the optimal route for the ORFI company chifles distribution is: 1-2-3-4-5-8-7-6-10-9-12-11-13-14-15-16-18-17-19-20-21-22-23-24-25-26-31-27-28-29-30-32-33-34-38-35-36-37-39-40-41-42-43-44-45-46-1, with 23089 meters of distance, optimizing in travel time 15% and travel distance 11%.
Implications: The application of the findings is expected to reduce the cost and time of distribution expended by the OFRI Company. Similar approaches also can be applied by other companies operating in the city
Application of “Travelling Salesman Problem” in Dynamic Programming for Efficient and Cost Effective Route Design for Distribution: Case of Chifles Distribution of ORFI Company, Ecuador
Purpose: The present study is designed to optimize a route for the distribution of chifles of the ORFI Company in school bars within the Río Verde parish of the Santo Domingo City, Republic of Ecuador.
Methodology: Time and distance data were collected regarding the route of the vendors, then distance matrices were developed between distribution points, and a graph was designed to find the best route using the Bellman-Hell-Karp algorithm.
Results: The sector graph had 46 nodes and the optimal route was found by applying dynamic programming with the Held-Karp mathematical algorithm, the optimal route for the ORFI company chifles distribution is: 1-2-3-4-5-8-7-6-10-9-12-11-13-14-15-16-18-17-19-20-21-22-23-24-25-26-31-27-28-29-30-32-33-34-38-35-36-37-39-40-41-42-43-44-45-46-1, with 23089 meters of distance, optimizing in travel time 15% and travel distance 11%.
Implications: The application of the findings is expected to reduce the cost and time of distribution expended by the OFRI Company. Similar approaches also can be applied by other companies operating in the city
Application of “Travelling Salesman Problem” in Dynamic Programming for Efficient and Cost Effective Route Design for Distribution
oai:ojs2.riiopenjournals.com:article/66Purpose: The present study is designed to optimize a route for the distribution of chifles of the ORFI Company in school bars within the Río Verde parish of the Santo Domingo City, Republic of Ecuador.
Methodology: Time and distance data were collected regarding the route of the vendors, then distance matrices were developed between distribution points, and a graph was designed to find the best route using the Bellman-Hell-Karp algorithm.
Results: The sector graph had 46 nodes and the optimal route was found by applying dynamic programming with the Held-Karp mathematical algorithm, the optimal route for the ORFI company chifles distribution is: 1-2-3-4-5-8-7-6-10-9-12-11-13-14-15-16-18-17-19-20-21-22-23-24-25-26-31-27-28-29-30-32-33-34-38-35-36-37-39-40-41-42-43-44-45-46-1, with 23089 meters of distance, optimizing in travel time 15% and travel distance 11%.
Implications: The application of the findings is expected to reduce the cost and time of distribution expended by the OFRI Company. Similar approaches also can be applied by other companies operating in the city
Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey
Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Estimation and Study of Forest Loss and Gain Using Spatial Dataset across Districts of Uttarakhand
Aims: To study and estimate the forest cover loss and gain across the 13 districts of Uttarakhand.
Place and Duration of Study: Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, between September 2021 and December 2021.
Methodology: We extracted forest cover time-series data from the year 2001 to the year 2020 from Hensen Global Forest Change Dataset. This data was then mapped to the shapefile created in ARC-GIS containing all 13 districts as a Feature Collection, which was then used to individually classify each region and to estimate the size of the loss of tree cover precisely over the district boundary.
Results: Our study shows forest loss of about (21,05,71,646 square meters) and forest gain of (6,00,79,072 square meters) cumulatively in all the districts of Uttarakhand from the year 2001 to 2020 at a spatial resolution of 30 meters where trees were identified as canopies greater than 5 meters in height.
Conclusion: Among the districts of Uttarakhand Udham Singh Nagar, Nainital, and Champawat alone contribute to the total tree cover loss area of 15061.7513801 ha. which is about 71.5 % of Uttarakhand’s total tree cover loss. These regions require monitoring and controlling deforestation and more detailed studies like this are required to analyze and prevent the causes of such great-scale deforestation. Analyzing districts apart from those mentioned above, it is observed that the amount of tree cover loss is greater than the reforestation
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Not AvailableJack (Artocarpus heterophyllus) is a multipurpose fruit-tree species with minimal genomic resources. The study reports developing comprehensive transcriptome data containing 80,411 unigenes with an N50 value of 1265 bp. We predicted 64,215 CDSs from the unigenes and annotated and functionally categorized them into the biological process (23,230), molecular function (27,149), and cellular components (17,284). From 80,411 unigenes, we discovered 16,853 perfect SSRs with 192 distinct repeat motif types reiterating 4 to 22 times. Besides, we identified 2741 TFs from 69 TF families, 53 miRNAs from 19 conserved miRNA families, 25,953 potential lncRNAs, and placed three functional eTMs in different lncRNA-miRNA pairs. The regulatory networks involving genes, TFs, and miRNAs identified several regulatory and regulated nodes providing insight into miRNAs' gene associations and transcription factor-mediated regulation. The comparison of expression patterns of some selected miRNAs vis-à-vis their corresponding target genes showed an inverse relationship indicating the possible miRNA-mediated regulation of the genes.Not Availabl
Not Available
Not AvailableJack (Artocarpus heterophyllus) is a multi-purpose out-breeding tree species of the family Moraceae. We generated 42,928,887 high-quality expressed sequence reads, assembled them into 89,356 unigenes, and discovered 16,853 unigene-based perfect SSRs in A. heterophyllus. Thirty-eight polymorphic SSRs were used to analyze the genetic diversity and population structure of 224 germplasm accessions of A. heterophyllus constituting three populations from three agro-climatic zones, namely Eastern Plateau and Hills, Middle Gangetic Plain Region, and Eastern Himalayan Region, encompassing five Eastern and North-Eastern states of India. At the 38 SSR loci, we detected 142 alleles with a mean of 3.74 alleles per locus. The PIC values for the loci ranged from 0.25 to 0.69. The maximum genetic diversity was recorded in Eastern Plateau and Hills (I = 0.98, He = 0.52). The ANOVA analysis indicated significantly higher within-population variation (90%) than between populations (10%). The indirect estimation of gene flow (Nm) from PhiPT indicated significant gene flow among all three populations. The population structure analysis showed at least four distinct groups among the three populations with different introgression degrees. The NJ-based clustering grouped the 224 germplasm accessions into three main clusters, each with three sub-clusters. However, we did not observe distinct geographical structure among populations except some clustering among the germplasm accessions of the populations of geographically close locations. The transcriptome dataset and the SSR markers developed in the study would boost the species' molecular characterization, conservation, and specific need-based improvement.Not Availabl
Not Available
Not AvailableJack (Artocarpus heterophyllus) is a multi-purpose out-breeding tree species of the family Moraceae. We generated 42,928,887 high-quality expressed sequence reads, assembled them into 89,356 unigenes, and discovered 16,853 unigene-based perfect SSRs in A. heterophyllus. Thirty-eight polymorphic SSRs were used to analyze the genetic diversity and population structure of 224 germplasm accessions of A. heterophyllus constituting three populations from three agro-climatic zones, namely Eastern Plateau and Hills, Middle Gangetic Plain Region, and Eastern Himalayan Region, encompassing five Eastern and North-Eastern states of India. At the 38 SSR loci, we detected 142 alleles with a mean of 3.74 alleles per locus. The PIC values for the loci ranged from 0.25 to 0.69. The maximum genetic diversity was recorded in Eastern Plateau and Hills (I = 0.98, He = 0.52). The ANOVA analysis indicated significantly higher within-population variation (90%) than between populations (10%). The indirect estimation of gene flow (Nm) from PhiPT indicated significant gene flow among all three populations. The population structure analysis showed at least four distinct groups among the three populations with different introgression degrees. The NJ-based clustering grouped the 224 germplasm accessions into three main clusters, each with three sub-clusters. However, we did not observe distinct geographical structure among populations except some clustering among the germplasm accessions of the populations of geographically close locations. The transcriptome dataset and the SSR markers developed in the study would boost the species' molecular characterization, conservation, and specific need-based improvement.Not Availabl