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EDM is a special type of non-traditional machining technique in which material removal takes place due to repeated electrical discharges at short intervals in the presence of a dielectric medium. It is used in high precision machining of all types of conductive materials such as metals, metallic alloys, graphite and even some ceramic materials. In EDM, the main output parameters are the material removal rate (MRR), electrode wear rate (EWR), and surface roughness ( R a ). It is generally desirable to obtain the maximum MRR with minimum EWR with good surface finish. The dielectrics play a vital role in machining. Even though EDM process has been traditionally used in die sinking industry mostly for machining hard materials, lighter materials like Ti alloy are machined more recently. In some cases, components made out of soft metals like Aluminium alloys are machined in EDM due to the intricacy of profiles, blind prismatic holes and inaccessible areas by other machining methods. This paper aims to investigate the effect of using different dielectrics, viz., biodiesel, transformer oil and kerosene on the material removal rate, electrode wear and surface roughness in EDM. Based on Taguchi’s design of experiments, machining were carried out on Aluminium Alloy 6063 specimens using a die-sinking EDM machine fitted with a copper electrode. The results show that the biodiesel as a dielectric has better performance in MRR, EWR and surface finish in comparison with kerosene and transformer oil. However, performance sustainability and the environmental effect of biodiesel have to be studied.

With weight reduction and component reliability being the top priority while designing automobile components, the selection and use of materials of a high strength-to-weight ratio is of vital importance. Less weight ensures low fuel consumption and hence low emissions thus having a great impact on the environment on a large scale. Brake rotors are one of the most important components in an automobile, which aid in stopping the vehicle by converting the kinetic energy of the moving vehicle into heat energy by means of friction. This study focuses on the use of abrasive particle (SiC)-reinforced aluminum metal matrix composite material for brake rotors which is expected to generate less heat during braking (due to friction) and also reduces the unsprung mass of the vehicle resulting in better handling. This paper discusses the design, structural, and thermal analysis; the manufacturing method; and the testing of silicon carbide-reinforced aluminum (Al 6061) matrix composite material for motorcycle brake rotor.

The objective of this study is to compare the Naive Bayes algorithm with Innovative Logistic Regression in order to enhance human activity identification for sitting and walking. To predict human activity, Naive Bayes and Innovative Logistic Regression are used with different training and testing splits. From each group, ten sets of samples are selected, yielding a total of twenty samples. About 80% of the data from an independent sample T test were utilized in the Gpower test (g power setup parameters: α = 0.05 and power = 0.80, β = 0.2). Compared to Naive Bayes (90.7210%), Innovative Logistic Regression (95.5680%) has higher accuracy, with a statistical significance value of P = 0.003 (p < 0.05). When compared to Naive Bayes, Innovative Logistic Regression has higher accuracy.

Device reconfigurability refers to the ability to choose N or P type for the same structure. Such reconfigurable operation is demonstrated herein for a silicon nanotube (SiNT) structure using three-dimensional (3D) technology computer-aided design (TCAD) numerical simulations. The reconfigurable field-effect transistor (RFET) can exhibit N - or P -type operation via the application of an appropriate bias to a program gate. The regular (i.e., control) gate is also present in the RFET. In the planar nanowire structure, the program gate is placed beside the regular/control gate. Since the SiNT structure has both inner and outer gates, we propose to use the inner gate as the control gate and the outer gate as the program gate, to achieve device reconfigurability in the SiNT structure. Two approaches are presented to achieve such reconfigurability, based on a (1) single or (2) double program gate. The metrics considered in this work are the ON current ( I ON ), OFF current ( I OFF ), I ON I OFF ratio, and unity-gain cutoff frequency ( f T ). The effects of the outer diameter, inner diameter, and tube wall thickness of the tube are also discussed. The outer and inner diameters of the tube are found to determine the above-mentioned performance parameters. While a smaller inner diameter is preferred from the point of view of the I ON I OFF ratio, a larger inner diameter is desired from the radio frequency (RF) perspective.

The present investigation deals with the antimetastatic role of luteolin (LUT) by inhibiting matrix metalloproteinase (MMP)-9 and -2 in azoxymethane (AOM)-induced colon carcinogenesis in Balb/C mice. Animals received AOM at a dosage of 15 mg/kg body weight intraperitoneally once a week for 3 weeks. AOM-induced mice was treated with LUT (1.2 mg of LUT/kg body weight/day orally). After the experimental period, the tumor markers such as γ-glutamyl transferase (GGT), 5′ nucleotidase (5′ND), cathepsin-D (Cat-D), and carcinoembroyonic antigen (CEA) were elevated upon induction with AOM. Subsequent treatment with LUT results in the reduction of the tumor markers was recorded. The expressions of MMP-9 and MMP-2 were analyzed by reverse transcription–polymerase chain reaction (RT-PCR) and immunofluorescence methods. The expressions of MMP-9 and MMP-2 were increased during AOM induction and upon treatment with LUT reduced the expressions. RT-PCR analysis of tissue inhibitor of matrix metalloproteinase (TIMP)-2 was limited during AOM-induced colorectal cancer (CRC). Supplementation of LUT increased the expression of TIMP-2. To conclude, LUT acts as an antimetastatic agent by suppressing MMP-9 and MMP-2 productions and upregulating TIMP-2 expression, thereby suggesting that LUT can be a chemotherapeutic agent against CRC.

We investigate the association of incremental pulse wave velocity (ΔC; the change in pulse wave velocity over a cardiac cycle) with cardiometabolic risk factors and report the first and (currently) the largest population-level data. In a cross-sectional study performed in a cohort of 1373 general population participants, ΔC was measured using clinically validated ARTSENS devices. There were 455 participants in the metabolic syndrome (MetS) group whose average ΔC was ~ 28.4% higher than that of the non-metabolic syndrome (Non-MetS) group. Females with MetS showed ~ 10.9% elevated average ΔC compared to males of the Non-MetS group. As the number of risk factors increased from 0 to 5, the average ΔC escalated by ~ 55% (1.50 ± 0.52 m/s to 2.33 ± 0.91 m/s). A gradual increase in average ΔC was observed across each decade from the younger (ΔC = 1.53 ± 0.54 m/s) to geriatric (ΔC = 2.34 ± 0.59 m/s) populations. There was also a significant difference in ΔC among the blood pressure categories. Most importantly, ΔC ≥ 1.81 m/s predicted a constellation of ≥ 3 risks with AUC = 0.615, OR = 2.309, and RR = 1.703. All statistical trends remained significant, even after adjusting for covariates. The study provides initial evidence for the potential use of ΔC as a tool for the early detection and screening of vascular dysfunction, which opens up avenues for active clinical and epidemiological studies. Further investigations are encouraged to confirm and establish the causative mechanism for the reported associations.

Given a graph G with a terminal set R ⊆ V ( G ) , the Steiner tree problem (STREE) asks for a set S ⊆ V ( G ) \\ R such that the graph induced on S ∪ R is connected. A split graph is a graph which can be partitioned into a clique and an independent set. It is known that STREE is NP-complete on split graphs White et al. (Networks 15(1):109–124, 1985). To strengthen this result, we introduce convex ordering on one of the partitions (clique or independent set), and prove that STREE is polynomial-time solvable for tree-convex split graphs with convexity on clique ( K ), whereas STREE is NP-complete on tree-convex split graphs with convexity on independent set ( I ). We further strengthen our NP-complete result by establishing a dichotomy which says that for unary-tree-convex split graphs (path-convex split graphs), STREE is polynomial-time solvable, and NP-complete for binary-tree-convex split graphs (comb-convex split graphs). We also show that STREE is polynomial-time solvable for triad-convex split graphs with convexity on I , and circular-convex split graphs. Further, we show that STREE can be used as a framework for the dominating set problem (DS) on split graphs, and hence the classical complexity (P vs NPC) of STREE and DS is the same for all these subclasses of split graphs. Finally, from the parameterized perspective with solution size being the parameter, we show that the Steiner tree problem on split graphs is W [2]-hard, whereas when the parameter is treewidth, we show that the problem is fixed-parameter tractable, and if the parameter is the solution size and the maximum degree of I ( d ), then we show that the Steiner tree problem on split graphs has a kernel of size at most ( 2 d - 1 ) k d - 1 + k , k = | S | .

Background: The present study analyzes the effects of preoperative serum albumin, hematocrit, and creatinine on postoperative outcomes in patients undergoing carpal tunnel decompression surgery. Methods: The American College of Surgeons National Quality Improvement Program (NSQIP) database was queried from 2011 to 2020. Albumin, hematocrit, and creatinine were collected for each patient, alongside covariates. Outcomes included 30‐day medical complications, 30‐day wound complications, return to the operating room, nonhome discharge, and extended postoperative length of stay. Bivariate t ‐tests and multivariate logistic regressions were conducted. For any outcome‐laboratory value pairs with significance on regression, area under the receiver operating characteristic curves (AUC) were constructed. Results: A total of 1440 patients with albumin, 3138 patients with hematocrit, and 3159 patients with creatinine levels were identified. Increased serum albumin was associated with lower odds of medical complications (aOR: 0.479, p = 0.035). An overall cohort cutoff of ≤ 3.5 g/dL (AUC: 0.79, p < 0.001) was predictive of medical complications. On multivariate logistic regression, increased hematocrit reduced the odds of medical complications (aOR: 0.889, p < 0.001). Predictive hematocrit cutoffs of ≤ 39.7% (AUC: 0.77, p < 0.001) and ≤ 36.6% (AUC: 0.74, p < 0.001) were identified for medical complications amongst male and female patients, respectively. Similarly, increased serum creatinine was associated with greater odds of medical complications (aOR: 1.684, p = 0.006). Creatinine cutoffs of ≥ 1.2 mg/dL (AUC: 0.58, p = 0.033) and ≥ 1.0 mg/dL (AUC: 0.59, p = 0.039) were identified for medical complications amongst male and female patients, respectively. Conclusions: Multiple preoperative serum values were predictive of postoperative medical complications, and laboratory value thresholds were identified in this carpal tunnel decompression cohort to aid in risk stratification.

We investigate the complexity of minimum total outer-connected domination in split graphs. Given a connected graph G , a minimum total outer-connected dominating set asks for a set D ⊆ V ( G ) such that it is a total dominating set and the graph induced on V ( G ) \\ D is connected. It is known that the Total Outer-Connected Domination problem (TOCD) in general graphs is NP-complete. A split graph is a graph in which the vertex set can be partitioned into a clique and an independent set. Panda et al., have established that the TOCD is NP-complete in split graphs. In this paper, we strengthen this NP-completeness result by presenting an interesting dichotomy: we show that TOCD is NP-complete in split graphs with Δ I = 3 ( K 1 , 5 -free split graphs) and present a polynomial-time algorithm for TOCD in split graphs with Δ I = 2 ( K 1 , 4 -free split graphs). We revisit the complexity of domination in split graphs, and prove that in Δ I = 3 split graphs the domination problem is NP-complete whereas in Δ I = 2 split graphs the domination problem is polynomial-time solvable.

Central obesity with cardiometabolic syndrome (CMS) is a major global contributor to human disease, and effective therapies are needed. Here, we show that cyclic GMP-selective phosphodiesterase 9A inhibition (PDE9-I) in both male and ovariectomized female mice suppresses preestablished severe diet-induced obesity/CMS with or without superimposed mild cardiac pressure load. PDE9-I reduces total body, inguinal, hepatic, and myocardial fat; stimulates mitochondrial activity in brown and white fat; and improves CMS, without significantly altering activity or food intake. PDE9 localized at mitochondria, and its inhibition in vitro stimulated lipolysis in a PPARα-dependent manner and increased mitochondrial respiration in both adipocytes and myocytes. PPARα upregulation was required to achieve the lipolytic, antiobesity, and metabolic effects of PDE9-I. All these PDE9-I-induced changes were not observed in obese/CMS nonovariectomized females, indicating a strong sexual dimorphism. We found that PPARα chromatin binding was reoriented away from fat metabolism-regulating genes when stimulated in the presence of coactivated estrogen receptor-α, and this may underlie the dimorphism. These findings have translational relevance given that PDE9-I is already being studied in humans for indications including heart failure, and efficacy against obesity/CMS would enhance its therapeutic utility.