54 research outputs found
Finite element analysis of micro end mill and simulation of burr formation in machining al6061-t6
The recent technological progressions in industries have offered ascent to the continually growing requests for microstructures, sensors, and parts. Micro-milling is a promising method to create these scaled down structures, sensors, and parts. Yet, micromilling still confronts some significant difficulties, tormenting further provision of this innovation. The most noticeable around them is micro burr formation. Burrs created along the completed edges and surfaces in micro-milling operation have huge effect on the surface quality and performance of the completed parts and microstructures. In any case, deburring of micro-parts is not conceivable because of bad accessibility and tight tolerances in micro segments. One of the methods to minimize micro burr formation in micro milling is by enhancing the geometry of the device. As minimization of micro burrs still remains a key test in micro machining, not many researchers have worked in this field. The main aim of the research work is to present finite element analysis of flat end mill micro cutters used in micro milling by varying geometry of the tools. Apart from this, study has been done in detail on burr formation in micro milling and what factors affect it. Burr formation simulation has been carried out while varying the tool geometry. The outcome of the research will be a static finite element analysis of micro burrs formed during micro-milling which can help in determining tool life and a detailed dynamic analysis of micro burrs formed during micro-milling operation in Al6061-T6 which can benefit the aerospace industry in various ways. The results obtained during the analysis may be used for further research for burr minimization through tool optimization and process control
Cost Effectiveness Analysis Evaluating Real-Time Characterization of Diminutive Colorectal Polyp Histology using Narrow Band Imaging (NBI)
Background: Endoscopists and new computer-aided programs can achieve performance benchmarks for real-time diagnosis of colorectal polyps using Narrow-Band Imaging (NBI), though do not perform as well as endoscopists with expertise in advanced imaging. Previous cost-effectiveness studies on optical diagnosis have focused on expert performance, potentially over-estimating its benefits.
Aim: Determine cost-effectiveness of an NBI ‘characterize, resect and discard (CRD)’ strategy using updated assumptions based on non-expert performance.
Methods: Markov model was constructed to compare cost-effectiveness of the CRD strategy, where diminutive polyps characterized as non-adenomas with high confidence are not resected and adenomas are resected and discarded, versus standard of care (SOC) in which all polyps are resected with histologic analysis. Rates related to NBI performance, missed polyps, polyp progression, malignancy, and complications, as well as quality-adjusted life years (QALYs) were derived from the literature. Costs were age and insurer-specific. Mean QALYs and costs were calculated using first order Monte Carlo simulation. Deterministic and probabilistic sensitivity analyses were conducted.
Results: The mean QALY estimates were similar for the CRD (8.563, 95% CI: 8.557-8.571) and SOC strategy (8.563, 8.557-8.571), but costs were reduced (2,800.27, mean incremental cost savings: 708 million to $1.06 billion annually. The model was sensitive to the incidence of tubular adenomas; the results were otherwise robust in all other one-way and probabilistic analyses.
Conclusions: An NBI CRD strategy is cost-effective when compared to the SOC, even when employed by non-experts. The appreciated benefit is primarily due to cost savings of the CRD strategy
Seasonal Variations and Trends in Hospitalization for Peptic Ulcer Disease in the United States: A 12-Year Analysis of the Nationwide Inpatient Sample
BACKGROUND: Peptic ulcer disease (PUD) is a major public health burden significantly impacting the cost of hospitalization in the United States (US). We examined the trends, characteristics, complications, cost, and seasonality of PUD-related hospitalizations from 2000 to 2011.
METHODS: With the use of the Nationwide Inpatient Sample from 2000 through 2011, we identified PUD-related hospitalizations using the International Classification of Diseases (ICD-9), 9th Revision, and the Clinical Modification code 531.00 to 534.91 as the principal discharge diagnosis. The total number of hospitalizations for each calendar month of the year were added over a 12-year period, and this number was divided by the number of days in that particular month to obtain the mean hospitalizations per day for each month.
RESULTS: The study found that 351,921 hospitalizations with the primary discharge diagnosis of peptic ulcer disease (PUD) occurred in the US between 2000 and 2011. This number dropped significantly from 49,524 to 17,499 between 2000 and 2011, and the rate of PUD-related mortality decreased from 4.3% to 3.1%. The mean age of the study population was 66.2 +/- 17.4 years; 52.3% were males, and 56.8% were white. The number of hospitalizations in the US peaked in the spring season (916/day), and reached a nadir in the fall season (861/day). The mean cost of PUD hospitalization increased significantly from 13,803 in 2011 (relative increase of 17%; p \u3c 0.001).
CONCLUSION: The incidence of PUD and its mortality has decreased significantly in the last decade, but its economic burden on the healthcare system remains high. A seasonal pattern of PUD hospitalization showed a peak in PUD-related admissions in the spring season and a trough in the fall season
Diffusion of Macromolecules across the Nuclear Pore Complex
Nuclear pore complexes (NPCs) are very selective filters that monitor the
transport between the cytoplasm and the nucleoplasm. Two models have been
suggested for the plug of the NPC. They are (i) it is a reversible hydrogel or
(ii) it is a polymer brush. We propose a mesoscopic model for the transport of
a protein through the plug, that is general enough to cover both. The protein
stretches the plug and creates a local deformation. The bubble so created
(prtoein+deformation) executes random walk in the plug. We find that for faster
relaxation of the gel, the diffusion of the bubble is greater. Further, on
using parameters appropriate for the brush, we find that the diffusion
coefficient is much lower. Hence the gel model seems to be more likely
explanation for the workings of the plug
LEARN: A multi-centre, cross-sectional evaluation of Urology teaching in UK medical schools
OBJECTIVE: To evaluate the status of UK undergraduate urology teaching against the British Association of Urological Surgeons (BAUS) Undergraduate Syllabus for Urology. Secondary objectives included evaluating the type and quantity of teaching provided, the reported performance rate of General Medical Council (GMC)-mandated urological procedures, and the proportion of undergraduates considering urology as a career. MATERIALS AND METHODS: LEARN was a national multicentre cross-sectional study. Year 2 to Year 5 medical students and FY1 doctors were invited to complete a survey between 3rd October and 20th December 2020, retrospectively assessing the urology teaching received to date. Results are reported according to the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). RESULTS: 7,063/8,346 (84.6%) responses from all 39 UK medical schools were included; 1,127/7,063 (16.0%) were from Foundation Year (FY) 1 doctors, who reported that the most frequently taught topics in undergraduate training were on urinary tract infection (96.5%), acute kidney injury (95.9%) and haematuria (94.4%). The most infrequently taught topics were male urinary incontinence (59.4%), male infertility (52.4%) and erectile dysfunction (43.8%). Male and female catheterisation on patients as undergraduates was performed by 92.1% and 73.0% of FY1 doctors respectively, and 16.9% had considered a career in urology. Theory based teaching was mainly prevalent in the early years of medical school, with clinical skills teaching, and clinical placements in the later years of medical school. 20.1% of FY1 doctors reported no undergraduate clinical attachment in urology. CONCLUSION: LEARN is the largest ever evaluation of undergraduate urology teaching. In the UK, teaching seemed satisfactory as evaluated by the BAUS undergraduate syllabus. However, many students report having no clinical attachments in Urology and some newly qualified doctors report never having inserted a catheter, which is a GMC mandated requirement. We recommend a greater emphasis on undergraduate clinical exposure to urology and stricter adherence to GMC mandated procedures
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have
fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in
25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16
regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of
correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP,
while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in
Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium
(LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region.
Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant
enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the
refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa,
an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of
PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent
signals within the same regio
Virtual 3D Modeling of Two Historic Barns in Bulloch County, GA (One Northwest of Statesboro and the Botanic Garden Barn)
This service-learning work is part of a larger project consisting in laser scanning and producing virtual, three-dimensional, computer-based, detailed models of eight (8) historic barns in Bulloch County, GA. The resulting spatial models (point clouds) will assist in the historical preservation of these now delicate and aging structures. In particular, this authoring group of students are currently working and focusing on two of those eight barns: (i) Dave & Carrie Welter’s Mule Barn, near the Northwest side of Statesboro, and (ii) Dan Bland’s Barn at Georgia Southern University Botanic Garden. After completion, the models will be donated to Dr. Brent W. Tharp who represents both, the Bulloch County Historical Society and the Georgia Southern Museum. This project gave our Civil Engineering and Construction team an opportunity to assist and serve our community in a service learning format while understanding and learning state-of-the-art laser scanning techniques
Small Scale Analysis of the Municipal Court System in St. Louis County
This presentation provides an analysis of three different municipal courts (St. John, Ferguson, and Kirkwood) in St. Louis County, serving as an overview of the great disparities in judicial processing and fee assessment in the region. The three courts were weighed against each other based on accessible demographic statistics and data collected during on-site visits by the authors. A list of distinct characteristics was made for each court, then a pros and cons chart was created based on similarities between the three. The per capita income and traffic tickets per capita were also compared among the three cities, demonstrating the unjust negative correlation between the two statistics. Population data was provided to enhance the analysis, further shedding light on the inequitable judicial treatment of minorities in low-income areas
- …