The estimated 10-year risk of first-onset cardiovascular disease in Swedish-born and non-Swedish-born primary healthcare patients.

BACKGROUND: SCORE2 has been introduced as an updated risk assessment tool for calculating the 10-year risk of first-onset cardiovascular disease (CVD). However, it does not account for ethnicity or socioeconomic status, known to affect CVD risk. This study investigated and compared SCORE2 estimates in Swedish-born and non-Swedish-born primary healthcare patients. The second aim was to examine if several risk factors could explain differences in CVD risk between the groups. METHODS: This was an observational, cross-sectional study. Data were obtained from the 4D Diabetes Project study, providing a total of 444 participants aged between 40 and 69 years. All participants had complete risk variable data necessary for the SCORE2 tool and no history of previous CVD. Descriptive analysis was conducted to compare distributions of risk factors between Swedes and immigrants and odds ratios of risk factors amongst these two groups in correlation to elevated CVD risk were calculated using logistic regression. RESULTS: Swedish-born patients showed a significantly higher risk of elevated CVD risk estimates (≥ 2.5% CVD risk increase for individuals < 50 years, respectively, ≥ 5% for individuals aged 51-69) than the non-Swedish-born population, even after adjustment for educational level (OR = 1.61, 95% CI 1.08-2.39). Weekly alcohol consumption implicated a risk of being classified as high risk of CVD risk, regardless of country of birth (OR = 1.93 CI 1.25-3.00). However, Swedes accounted for most of the alcohol consumption (62.6% vs. 19.6%). No other explanatory variable showed significance in association with elevated CVD risk. CONCLUSIONS: Swedish-born patients were found to be at higher risk of an increased 10-year CVD risk. The association of alcohol consumption with elevated CVD risk needs to be further studied in longitudinal studies in representative populations, notably among Sweden's diverse ethnic groups.

A rare case of IgA lambda multiple myeloma in a 32-year-old woman with t(14;16) translocation associated with kidney injury and non-albumin proteinuria.

BACKGROUND: Multiple myeloma (MM) is a malignant disorder characterized by monoclonal differentiated plasma cells. While it is more commonly diagnosed in elderly individuals, it can also affect younger populations, though with a lower incidence. CASE PRESENTATION: Here, we present the case of a 32-year-old woman diagnosed with IgA lambda MM. She presented with fatigue, nausea, acute kidney injury (AKI) with a rapid increase in creatinine, and anemia. A kidney biopsy was done to rule out a rapidly progressive glomerular disease and a diagnosis was thus reached. A genetic workup revealed t(14;16) translocation and an extra copy of TP53. The patient received aggressive intravenous steroids and intravenous fluid resuscitation, resulting in an improvement in renal function. Treatment with daratumumab in combination with bortezomib, thalidomide, and dexamethasone was initiated and well tolerated. Despite the generally poor prognosis of IgA MM, our case emphasizes the importance of considering MM in young patients with unexplained kidney injury. CONCLUSION: Early recognition and prompt intervention are essential in managing MM patients, especially in those with high-risk cytogenetic abnormalities. This case serves as a reminder for clinicians to maintain a high index of suspicion for MM, even in younger populations, when presented with unexplained kidney injury.

Assessment of consolidative multi-criteria decision making (C-MCDM) algorithms for optimal mapping of polymer materials in additive manufacturing: A case study of orthotic application.

Objective: The objectives of this research are twofold. The primary goal is to introduce, investigate, and contrast consolidative multi-criteria decision-making (C-MCDM) approaches. The second objective is the investigation of five alternative additive manufacturing materials. Methods: It integrates the subjective and objective weights using the Bayes hypothesis in conjunction with a normal method. Chang's Extent Analysis Method under fuzzy logic is used to estimate subjective weights and the CRITIC approach is used for assessing objective weights. Ranking techniques, including the simple ranking process (SRP), multi-objective optimization based on ratio analysis (MOORA), measurement alternatives and ranking according to compromise solution (MARCOS), and technique for order preference by similarity to ideal solution (TOPSIS) are applied. It also encompasses sensitivity analysis based on Kendall's coefficient of concordance and rank reversal phenomenon analysis. Spearman's rank correlation coefficient, a weighted rank measure of correlation, and rank similarity coefficient are among the metrics used to evaluate agreement between different approaches. It entails gathering expert opinions regarding the importance of various criteria as well as conducting extensive experiments. Results: The findings of the study indicate that polylactic acid is the best material to use for orthoses. When compared to the other MCDM approaches being discussed, SRP is the most reliable approach. It is also demonstrated that the SRP, MARCOS, and TOPSIS methods are rank reversal-free. Furthermore, SRP exhibits a very poor association with the TOPSIS technique but a strong correlation with the MOORA and MARCOS approaches. Conclusions: To ensure results reliability, it is necessary to consider both the subjectivity and objectivity of weights as well as apply multiple MCDM methodologies in addition to sensitivity analysis.

Smoking Habits and Nicotine Dependence Among the General Lebanese Population Before and During Both the Economic Crisis and COVID-19 Pandemic.

Objective: Smoking habits have widely changed over time; however, they remain a well-known fashion that risks people's health. In addition, nicotine addiction depends on the interplay between several factors. Our study aimed to understand the smoking habits and nicotine dependence in the Lebanese population before (September 2019) and during (June 2020) the economic crisis and COVID-19 pandemic. Methods: This observational cross-sectional survey-based study included 1560 Lebanese individuals aged between 13 and 75 years old from June till October 2020. Data collection was performed through an electronic survey including patients' demographics and validated instruments to assess addiction to nicotine (CAGE, Four C's, Fagerström test, and Smoker's profile scores). Results: Out of 1560 participants, 794 (50.9%) were males. The mean age was 26.5 ± 11.69 years, and 67.8% were aged between 18 and 25 years old. We found that 865 (55.4%) participants were smokers. In addition, smoking cigarettes or vaping, significantly increased between September 2019 and June 2020. Our smoker group showed a high CAGE positivity (P < .001), marked compulsion (P < .001), and a considerable lack of self-control to surcease smoking (P < .001). Furthermore, the nicotine dependence score (NDS) increased with age (B = .166) and decreased with higher educational levels (B = -.219). Conclusion: During the economic crisis and the COVID-19 pandemic, the Lebanese population showed an increased prevalence of smoking, a high level of CAGE positivity, strong compulsion, and a significant lack of self-control when it came to quitting smoking. This strongly entails public health measures for smoking cessation through national awareness campaigns.

Arab world's impact on bladder cancer research and opportunities for growth: A bibliometric review study.

BACKGROUND: Bladder Cancer (BC) is a widespread form of cancer that affects over 1.6 million people globally. The majority of cases are diagnosed as urothelial carcinoma, with a higher likelihood of diagnosis in men and with increasing age. The Arab world (AW) is one of the regions with the highest incidence and mortality rates of BC, and the average age of diagnosis is between 40 and 49 years in North Africa and the Middle East. This study aims to assess the activity and distribution of BC publications in the AW. METHODS: A systematic search across MEDLINE and Embase databases spanning 2007 to 2021 identified 1208 English-language articles on bladder cancer with Arab affiliations. The dataset was normalized against the average population and GDP (2007-2020) for 22 Arab countries. Statistical analyses via SPSS and visualizations with VOSviewer unveiled collaboration patterns and thematic trends in Arab bladder cancer research. RESULTS: A total of 1208 BC publications were published in the AW, representing 0.24% of all biomedical publications. Egypt topped the list with the highest number of publications. The co-authorship analysis generated by VOSviewer revealed that out of 4766 authors, 161 met the minimum threshold of 5 publications. CONCLUSION: The findings reveal that Egypt and Jordan are at the forefront of BC research in the region, while other Arab countries are lagging behind despite being heavily impacted by the disease. To drive progress in the field, it's important to uncover the obstacles impeding BC research in these countries and implement effective solutions to overcome them.

An Insight into the Characteristics of 3D Printed Polymer Materials for Orthoses Applications: Experimental Study.

Knee orthoses assist patients with impaired gait through the amendment of knee abnormalities, restoration of mobility, alleviation of pain, shielding, and immobilization. The inevitable issues with laborious traditional plaster molding procedures for orthoses can be resolved with 3D printing. However, a number of challenges have limited the adoption of 3D printing, the most significant of which is the proper material selection for orthoses. This is so because the material used to make an orthosis affects its strength, adaptability, longevity, weight, moisture response, etc. This study intends to examine the mechanical, physical, and dimensional characteristics of three-dimensional (3D) printing materials (PLA, ABS, PETG, TPU, and PP). The aim of this investigation is to gain knowledge about these materials' potential for usage as knee orthosis materials. Tensile testing, Olympus microscope imaging, water absorption studies, and coordinate measuring machine-based dimension analysis are used to characterize the various 3D printing materials. Based on the investigation, PLA outperforms all other materials in terms of yield strength (25.98 MPa), tensile strength (30.89 MPa), and shrinkage (0.46%). PP is the least water absorbent (0.15%) and most flexible (407.99%); however, it is the most difficult to fabricate using 3D printing. When producing knee orthoses with 3D printing, PLA can be used for the orthosis frame and other structural elements, PLA or ABS for moving parts like hinges, PP for padding, and TPU or PP for the straps. This study provides useful information for scientists and medical professionals who are intrigued about various polymer materials for 3D printing and their effective utilization to fabricate knee orthoses.

Pediatric Oncology, Palliative Care and Low- or Middle- Income Countries: A Call for Action.

Pediatric oncology, which includes cancer screening and therapy in children, poses significant challenges in low- and middle-income countries (LMICs). Palliative care improves children's and their families' quality of life. In LMICs, palliative care resources are scarce, resulting in poor symptom management, psychological support, and spiritual care. All relevant English-language articles on pediatric palliative oncology were searched in PubMed, Google Scholar, Scopus, and Medline databases using the following keywords: "Pediatric Oncology," "Pediatric Palliative Oncology," "Pediatric Palliative Care," "Palliative Care," "Child Cancer," and "Lower- and Middle-Income Countries." This study highlights the significance of incorporating palliative care early in therapy and the recommendations may improve the competence of information provided by medical professionals to patients and families. LMICs have the potential to improve overall treatment and outcomes for child cancer patients and their families by prioritizing the integration of palliative care, guaranteeing a compassionate and dignified attitude toward the disease.

Prediction of Mechanical Properties for Carbon fiber/PLA Composite Lattice Structures Using Mathematical and ANFIS Models.

This study investigates the influence of design, relative density (RD), and carbon fiber (CF) incorporation parameters on mechanical characteristics, including compressive modulus (E), strength, and specific energy absorption (SEA) of triply periodic minimum surface (TPMS) lattice structures. The TPMS lattices were 3D-printed by fused filament fabrication (FFF) using polylactic acid (PLA) and carbon fiber-reinforced PLA(CFRPLA). The mechanical properties of the TPMS lattice structures were evaluated under uniaxial compression testing based on the design of experiments (DOE) approach, namely, full factorial design. Prediction modeling was conducted and compared using mathematical and intelligent modeling, namely, adaptive neuro-fuzzy inference systems (ANFIS). ANFIS modeling allowed the 3D printing imperfections (e.g., RD variations) to be taken into account by considering the actual RDs instead of the designed ones, as in the case of mathematical modeling. In this regard, this was the first time the ANFIS modeling utilized the actual RDs. The desirability approach was applied for multi-objective optimization. The mechanical properties were found to be significantly influenced by cell type, cell size, CF incorporation, and RD, as well as their combination. The findings demonstrated a variation in the E (0.144 GPa to 0.549 GPa), compressive strength (4.583 MPa to 15.768 MPa), and SEA (3.759 J/g to 15.591 J/g) due to the effect of the studied variables. The ANFIS models outperformed mathematical models in predicting all mechanical characteristics, including E, strength, and SEA. For instance, the maximum absolute percent deviation was 7.61% for ANFIS prediction, while it was 21.11% for mathematical prediction. The accuracy of mathematical predictions is highly influenced by the degree of RD deviation: a higher deviation in RD indicates a lower accuracy of predictions. The findings of this study provide a prior prediction of the mechanical behavior of PLA and CFRPLA TPMS structures, as well as a better understanding of their potential and limitations.

Increased Risk of Colorectal Cancer in Patients With Celiac Disease: A Population-Based Study.

BACKGROUND AND AIM: The association between celiac disease (CD) and the development of small bowel lymphoproliferative disorders and esophageal adenocarcinoma has been established in the literature. However, there is only a little evidence demonstrating an increased risk of colorectal cancer (CRC) in patients with CD. Hence, we conducted a cross-sectional population-based study to evaluate the risk of developing CRC in patients who have had a diagnosis of CD. METHODOLOGY: We used a commercial database (Explorys Inc, Cleveland, OH), which includes electronic health records from 26 major integrated US healthcare systems. Patients aged 18-65 years were included. Patients with inflammatory bowel disease (IBD) were excluded. Multivariate analysis using backward stepwise logistic regression was performed to calculate the risk of developing CRC in potential confounders. A two-sided P-value <0.05 was considered statistically significant. RESULTS: 79,843,332 individuals were screened in the database and 47,400,960 were selected in the final analysis after accounting for inclusion and exclusion criteria. Using a stepwise multivariate regression analysis, the odds of having CRC among patients with CD was 10.18 (95% CI 9.72-10.65) (P-value <0.001). The odds also remained high among males 1.49 (95% CI 1.36-1.63), African Americans 1.51 (95% CI 1.35-1.68), patients who have type 2 diabetes mellitus (T2DM) 2.71 (95% CI 2.66-2.76), are smokers 2.49 (95% CI 2.44-2.54), are obese 2.21 (95% CI 2.17-2.25), and are alcoholic 1.72 (95% CI 1.66-1.78). CONCLUSION: Our study demonstrates that patients with CD are frequently found to have CRC even when adjusting for common risk factors. This adds to the literature and helps spread awareness to clinicians that the effects of CD are not only limited to the small bowel as the disease tends to involve other parts of the gastrointestinal tract also, especially the colon. The threshold to screen patients with CD should be considered to be lowered.

Venetoclax: A New Partner in the Novel Treatment Era for Acute Myeloid Leukemia and Myelodysplastic Syndrome.

BACKGROUND: Acute Myeloid Leukemia (AML) and Myelodysplastic Syndrome (MDS) are two closely related blood cancers that are more frequent in older adults. AML is the most common type of adult acute leukemia, and MDS is characterized by ineffective blood cell production and abnormalities in the bone marrow and blood. Both can be resistant to treatment, often due to dysfunction in the process of apoptosis, the body's natural mechanism for cell death. Venetoclax, an orally-administered medication that selectively targets the BCL-2 protein, has shown promise in enhancing treatment sensitivity in some hematological malignancies by reducing the apoptotic threshold. This review aims to evaluate the effectiveness of venetoclax in treating AML and MDS, as well as potential mechanisms of resistance to the medication. METHODS: A literature search was conducted utilizing PUBMED to capture all relevant research articles on the use of venetoclax as a therapy for both diseases. The MeSH terms "acute myeloid leukemia", "myelodysplastic syndrome" and "venetoclax" were searched. Furthermore, Clinicaltrials.gov was accessed to ensure the inclusion of all ongoing clinical trials. RESULTS: Although Venetoclax showed modest results as a single-agent therapy in AML, venetoclax-based combination therapies? mainly with hypomethylating agents or low-dose cytarabine? yielded significantly positive results. Preliminary results oN the use of venetoclax-based combination therapy with HMA, mainly azacitidine, in unfit high-risk MDS also yielded optimistic results. Identification of mutations for which various drugs have been approved has spurred active investigation of venetoclax in combination trials. CONCLUSION: Venetoclax-based combination therapies have been shown to induce rapid responses and increase overall survival in AML patients unfit for intensive chemotherapy. These therapies are also yielding positive preliminary results in high-risk MDS patients in phase I trials. Resistance to venetoclax and drug-related toxicity are two main obstacles that need to be overcome to reap the full benefits of this therapy.

Increased Risk of Non-Alcoholic Steatohepatitis in Patients With Inflammatory Bowel Disease: A Population-Based Study.

Background and objective The global health burden of inflammatory bowel disease (IBD) stems from its increasing incidence over the years. Comprehensive studies on the topic hypothesize that IBD plays a more dominant in the development of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). In light of this, we conducted this study with the aim of assessing the prevalence and risk factors of developing NASH in patients who have had a diagnosis of ulcerative colitis (UC) and Crohn's disease (CD). Methodology A validated multicenter and research platform database of more than 360 hospitals from 26 different healthcare systems across the United States from 1999 to September 2022 was utilized for conducting this study. Patients aged 18-65 years were included. Pregnant patients and individuals diagnosed with alcohol use disorder were excluded. The risk of developing NASH was calculated using a multivariate regression analysis to account for potential confounding variables including male gender, hyperlipidemia, hypertension, type 2 diabetes mellitus (T2DM), and obesity. A two-sided p-value <0.05 was considered statistically significant, and all statistical analyses were performed using R version 4.0.2 (R Foundation for Statistical Computing, Vienna, Austria, 2008). Results A total of 79,346,259 individuals were screened in the database and 46,667,720 were selected for the final analysis based on the inclusion and exclusion criteria. Using multivariate regression analysis, the risk of developing NASH among patients with UC and CD was calculated. The odds of having NASH among patients with UC was 2.37 (95% CI: 2.17-2.60, p<0.001). Similarly, the odds of having NASH were high in patients with CD as well, at 2.79 (95% CI: 2.58-3.02, p<0.001). Conclusion Based on our findings, patients with IBD have an increased prevalence and higher odds of developing NASH after controlling for common risk factors. We believe that a complex pathophysiological relationship exists between both disease processes. Further research is required to establish appropriate screening times to enable earlier disease identification and thereby improve patient outcomes.

Neurofibromatosis type 1 system-based manifestations and treatments: a review.

INTRODUCTION: Neurofibromatosis type 1 (NF1) is a genetic disorder caused by a mutation in the NF1 gene. This disease presents with various system-based manifestations, including cardiac, musculoskeletal, and neuronal issues, which have been well-studied in previous research and have prompted the development of current and emerging treatments. These treatments, mainly medications targeting specific manifestations of NF1, aim to mitigate the negative impacts of the disease on patients' lives. NF1 is associated with an increased risk of malignancy and a significant decrease in life expectancy. In this paper, we review the current and emerging treatments for NF1 in relation to its system-based manifestations. METHODS: We conducted an extensive literature search using specific keywords through databases such as PubMed, Scopus, and Cochrane. The articles we found were compiled and subjected to strict inclusion and exclusion criteria. RESULTS: Pharmacological advances have led to the development of products that hold promise as future treatments for NF1. Given the diverse manifestations that can affect multiple organ systems in patients with NF1, it is important to consider a variety of treatment options to achieve optimal results. However, one of the major challenges in diagnosing and treating NF1 is that patients present asymptomatically, making it necessary to rely on clinical features for diagnosis. CONCLUSION: In conclusion, NF1 is a complex disease with varying manifestations and a growing field of pharmacologic treatments. The information presented in this article synthesizes current knowledge and available therapies for NF1.

Landscape of Guillain-Barré Syndrome Interventional Clinical Trials.

INTRODUCTION: Guillain-Barré syndrome (GBS) is an immune-mediated polyradiculoneuropathy that remains a debilitating disease despite medical treatment. Numerous challenges still exist, including the development of disease-modifying therapies that can improve prognosis, particularly in patients with poor prognostic outcomes. In this study, we explored clinical trials related to GBS, analyzed the trial characteristics, suggested some ideas for improvement, and discussed recent advances. METHODS: On December 30, 2021, the authors searched ClinicalTrials.gov for all interventional and therapeutic clinical trials related to GBS, without any restrictions on the date or location. Trial characteristics including trial duration, location, phase, sample size, and publications were retrieved and analyzed. RESULTS: Twenty-one trials fulfilled the selection criteria. Clinical trials were conducted in 11 different countries, most of them occurring in Asia. On average, the trial duration across the phases was around 2 years. About two-thirds of trials were completed, and 39% of trials were in the early phases (1 and 2). Only 24% of all trials and 60% of completed trials have publications in this study. CONCLUSIONS: The study revealed a low number of trials, lack of geographic diversity, scanty enrollment of patients, and paucity of clinical trial duration and publications regarding GBS clinical trials. Optimization of GBS trials is fundamental to achieving effective therapies for this disease.

Compression Performance and Failure Analysis of 3D-Printed Carbon Fiber/PLA Composite TPMS Lattice Structures.

Triply periodic minimum surface (TPMS)-based lattice structures have gained interest for their outstanding capacity to absorb energy, their high load-bearing capacity, and their high surface-to-volume ratio. This study considered three TPMS cell topologies, including Diamond, Gyroid, and Primitive. The FDM process was used to print the lattice structures with two materials: pure polylactic acid (PLA) and carbon fiber-reinforced PLA (PLA + CF). The influence of carbon fiber (CF) incorporation, unit cell type (topologies) and size, and relative density (RD) on mechanical properties and failure patterns were explored comprehensively under uniaxial compression testing. The results demonstrate a change in the compressive modulus (0.09 to 0.47 GPa), compressive strength (2.98 to 13.89 MPa), and specific energy absorption (SEA) (0.14 MJ/m3/g to 0.58 MJ/m3/g) due to the influence of CF incorporation, cell type and size, and RD. Results indicate that the Diamond structure outperformed both Primitive and Gyroid structures in terms of compressive modulus and strength, and SEA. All the CF-based TPMS structures showed a higher compressive modulus. Compressive strength and energy absorption capacity were both slightly enhanced in most PLA + CF-based Diamond structures. On the contrary, Gyroid and Primitive structures showed better performance for pure PLA-based structures in terms of compression strength and specific absorption energy.

Newly-identified Pathways Relating Vitamin D to Carcinogenesis: A Review.

BACKGROUND: The epidemiological relationship between vitamin D levels and cancer has been thoroughly investigated. Published data from large studies appear to corroborate a significant relationship between higher serum vitamin D concentrations and improved survival. Mechanistic reviews on commonly-studied cancers - including breast cancer, colon cancer and melanoma - focus predominantly on data from older studies. In outlining avenues for future research, we believe there is utility in summarizing novel findings introduced to the literature. MATERIALS AND METHODS: In this narrative review, we used MEDLINE, PUBMED and Cochrane databases to identify mechanistic studies published from January 1, 2015 onwards exploring this topic. RESULTS: Twenty-five mechanistic studies were included in this review. It was found that vitamin D plays a critical role in both direct (i.e. tumor gene expression, proliferation, invasiveness, sensitivity to chemotherapy etc.) and indirect (i.e. effects on the tumor microenvironment and immunomodulation) tumor suppression mechanisms. CONCLUSION: These newly-identified pathways warrant further research, with the hopes that we may understand how and when vitamin D supplementation can be integrated into precision medicine therapeutics for cancers of the breast, colon and skin. Cancer care providers should consider recommendations to screen for vitamin D deficiency in this population.

A Comprehensive Analysis of the Effect of Graphene-Based Dielectric for Sustainable Electric Discharge Machining of Ti-6Al-4V.

Titanium alloys, especially Ti-6Al-4V, which is considered a difficult-to-cut material, bears numerous applications in aerospace and biomedical sectors. The criticality of the accurate formation of the machined cavity for the said applications and properties of Ti-6Al-4V accentuated the use of electric discharge machining (EDM). However, the issues of lower material removal rate (MRR) and tool wear (TWR) discouraged the use of EDM. These inherent issues hold a pivotal role regarding the sustainable machining of Ti-alloy. Therefore, in this research the potentiality of kerosene-based dielectric, having graphene nanoparticles, is comprehensively examined for the sustainable EDM of Ti-6Al-4V, which was not focused upon yet. Experimentation was performed under Taguchi's design (L18) with three types of electrodes, namely Aluminum, Brass and Copper. In total, 36 experiments were conducted, of which 18 were with graphene-mixed dielectric and the remaining were with kerosene. Experimental results reveal that the brass electrode with negative tool polarity yields higher MRR for both types of dielectrics. The maximum MRR (7.602 mm3/min) achieved with graphene mixed dielectric is 64.5% greater as compared to that obtained with kerosene (4.621 mm3/min). Moreover, the minimum TWR obtained for graphene-based dielectric, i.e., 0.17 mg/min is approximately 1.5 times less than that achieved with kerosene.

Milling Microchannels in Monel 400 Alloy by Wire EDM: An Experimental Analysis.

This paper presents the results of an investigation on the capacity of wire electrical discharge machining (WEDM) to produce microchannels in the Nickel-based alloy, Monel 400. The main objective of the current study is to produce microchannels with desired/target geometry and acceptable surface quality. Square cross-sectional microchannels with dimensions of 500 × 500 µm were investigated. Experiments were conducted based on the one-factor-at-a-time approach for the key input WEDM process parameters, namely pulse-on time (TON), pulse-off time (TOFF), average gap voltage (VGAP), wire feed (WF), and dielectric flow rate (FR). Dimensional accuracy, machining speed, surface roughness, surface morphology, microhardness, and microstructure were analyzed to evaluate the microchannels. The minimum errors of 6% and 3% were observed in the width and depth of the microchannels, respectively. Furthermore, microchannels with enhanced surface integrity could be produced exhibiting smooth surface morphology and shallow recast layer (~0-2.55 µm).

The potentiality of sinking EDM for micro-impressions on Ti-6Al-4V: keeping the geometrical errors (axial and radial) and other machining measures (tool erosion and work roughness) at minimum.

Ti-6Al-4V is a material of high interest in various industrial sectors including biomedical, automotive and aerospace. Conventional means of machining encounter different types of difficulties. Electric discharge machining (EDM) is not a contest of hardness. Circular impressions of micro-depth are produced in Ti-6Al-4V using four different electrode materials including aluminum, brass, graphite and copper, each assigned positive and negative polarity. In order to get precise control over the geometry of micro-impressions dimensional accuracy and tool wear must be controlled. Thus, EDM performance has been evaluated in terms of axial dimensional error (D.E_Axi), radial dimensional error (D.E_Rad), tool length reduction (TLR), and surface roughness (SR). Since the EDM process is stochastic in nature therefore in addition to tool polarity only two factors are considered as variables, i.e. discharge current and pulse-time-ratio (ration of on-time to off-time). The behaviors of each of the four electrode materials are compared together under each of the two polarities and two variables for each of the four response characteristics. The search is carried out to select the most appropriate tool electrode polarity (common for all responses) and a single common electrode capable of minimizing all the four response measures simultaneously. Moreover, microstructures of the machined impressions are discussed. Without any compromise in the minimum values of response measures, no single polarity and a single electrode are found common. However, with a slight compromise over the machining measures negative tool polarity and copper electrode served the purpose of set objectives (minimum of D.E, TLR, and SR). The expanse of compromise is found to be ≤ 50 µm in axial and radial dimensional errors, 0.8 µm in surface roughness and no compromise in tool length reduction if the copper electrode is assigned with negative polarity.