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Currently, the research efforts on machining indices such as tool wear, surface roughness, power consumption etc. is well reported in literature, but energy analysis based on material removal methods and machine learning has received comparatively little attention. Therefore, the present work deals with the research efforts on simultaneous reduction of specific cutting energy in sustainable machining of Inconel 601 alloy with different machine learning models. The studies were conducted using dry, minimum quantity lubrication (MQL), nano-MQL, cryogenic, and hybrid cooling methods (cryo-nano-MQL). The specific cutting energy (SCE) values were calculated based on the data obtained from power consumption and material removal rate. Subsequently, the SCE data is employed to construct the crucial maps, which are then utilized in several sophisticated machine learning models, including Multiple Linear Regression, Lasso Regression, Bayesian Ridge Regression, and Voting Regressor, to facilitate the predictive modeling of outcomes. The findings of the study indicate that the Bayesian model exhibits a comparatively reduced error rate and a closely aligned R2 value when compared to other prediction models. Moreover, as a novelty, nanoparticles addition into hybrid cooling methods (cryo + nano + MQL) also showed better performance as well as 0.3 % less specific cutting energy than only cryo method which is previously used in former studies.

Byline: Hakan. Yilmaz, Merve. Aydin Aim: Since it is difficult to understand by patients or parents, YouTube[TM] videos can be used to describe space maintainers. However, the reliability and quality [...]

AbstractPurposeThe aim of our study was to assess left ventricle and right ventricle systolic and diastolic functions in obese adolescents with metabolic syndrome using conventional echocardiography and pulsed-wave tissue Doppler imaging and to investigate carotis intima-media thickness, and asymmetric dimethyl arginine levels.MethodsA total of 198 obese adolescents were enrolled in the study. The obese patients were divided into metabolic syndrome group and non-metabolic syndrome group. All subjects underwent laboratory blood tests, including asymmetric dimethyl arginine, complete two-dimensional, pulsed, and tissue Doppler echocardiography, and measurement of the carotid intima-media thickness.ResultsObese adolescents were characterised by enlarged left end-diastolic, end-systolic and left atrial diameters, thicker left and right ventricular walls compared with non-obese adolescents. The metabolic syndrome group had normal left ventricle systolic function, impaired diastolic function, and altered global systolic and diastolic myocardial performance. In the metabolic syndrome obese group patients, left ventricle mass was found positively correlated with body mass index, waist and hip circumferences, diastolic blood pressure, age, and waist-to-hip circumference ratio. The carotid intima-media thickness was found positively correlated with waist and hip circumferences and total cholesterol levels. Asymmetric dimethyl arginine levels were found positively correlated with systolic blood pressure, waist-to-hip circumference ratio, and diastolic blood pressure.ConclusionsThe results of this study demonstrate that metabolic syndrome in adolescence is associated with significant changes in myocardial geometry and function. In addition, it has been associated with a high level of asymmetric dimethyl arginine concentration and thicker carotid intima-media thickness reflecting endothelial dysfunction.

We studied the synthesis and characterization of polymeric coordination complexes of Co(II) and Ni(II) ions with pyrazine-2,3-dicarboxylic acid and 1-vinylimidazole. The e lemental analysis, infrared spectroscopy, powder X-ray diffraction, magnetic susceptibility, thermal analysis and X-ray single crystal techniques were used in the characterization. The X-ray single crystal analysis suggests that the pyrazine-2,3-dicarboxylato ligand acts as a bridging ligand through the oxygen atoms of the carboxylate groups and the nitrogen atoms on the pyrazine ring. The 1-vinylimidazole ligand behaves as a monodentate ligand via the ring nitrogen atom. Further, the H2adsorption studies were carried out at 75 K for various increasing pressures and the highest H2adsorption performances for Co(II) and Ni(II) complexes were estimated as 2.66 and 2.99 wt% at 87 bar. The theoretical calculations using the crystal data were also performed to determine the voids in the structure of Co(II) complex.

AVMs are vessel anomalies where a connection between arterial and venous systems is present and the capillary bed is absent between the two. AVMs tend to present with seizures, headaches, focal neurological deficits and hemorrhage. Hemorrhage is the most common form of presentation. AVM's have a 2–4% annual risk of hemorrhage. Certain studies report this rate as 1%. The greatest discussion in AVM treatment is whether to use interventional treatment or monitor with medical treatment. There are 3 modalities that can be used for interventional treatment; microsurgical resection, endovascular embolization and stereotactic radiosurgery. Combined techniques are also possible. We defined the ‘radical combined approach’ combines embolization and microsurgery. We will discuss this procedure in this article as we believe it has several advantages.

Coronavirus disease 2019 (COVID-19) is a rapidly spreading deadly respiratory disease that emerged in the city of Wuhan in December 2019. As a result of its rapid and widespread transmission, the WHO declared a pandemic on March 11, 2020 and studies evaluating mortality and prognosis in COVID-19 gained importance. The aim of this study was to determine the factors affecting the survival of COVID-19 patients followed up in a tertiary intensive care unit (ICU) and undergoing chest computed tomography (CT) scoring. This retrospective cross-sectional study was conducted with the approval of Uşak University Medical Faculty Ethics Committee between July and September 2020. It included 187 symptomatic patients (67 females, 120 males) with suspected COVID-19 who underwent chest CT scans in the ICU. Demographics, acute physiology and chronic health evaluation (APACHE II), chest CT scores, COVID-19 real-time polymerase chain reaction (RT PCR) results, and laboratory parameters were recorded. SPSS 15.0 for Windows was used for the data analysis. The ages of the patients ranged from 18 to 94 and the mean age was 68.0 ± 13.9 years. The COVID-19 RT PCR test was positive in 86 (46.0%) patients and 110 patients (58.8%) died during the follow-up. ICU stay (P = .024) and total invasive mechanical ventilation time (P < .001) were longer and blood urea nitrogen (BUN) was higher (P < .001) in the nonsurvivors. Patients with an APACHE II score of 23 and above had a 1.12-fold higher mortality rate (95% CI 0.061–0.263). There was no significant difference in total chest CT score between the survivors and nonsurvivors (P = .210). Chest CT score was not significantly associated with mortality in COVID-19 patients. Our idea that COVID-19 will cause greater mortality in patients with severe chest CT findings has changed. More studies on COVID-19 are needed to reveal the markers that affect prognosis and mortality in this period when new variants are affecting the world.

AbstractBackground/aims:No data are available examining the relationship between carotid intima media thickness (IMT) and left ventricular mass (LVM) in obese adolescents with non-alcoholic fatty liver disease (NAFLD). Therefore, we investigated LVM and carotid IMT in obese adolescents with NAFLD.Methods:Eighty obese adolescents and 37 lean subjects were enrolled in the study. The obese subjects were divided into two subgroups based on the presence or absence of fatty liver with high transaminases (NAFLD group and non-NAFLD group). Fasting blood samples were assayed for serum transaminases, glucose and insulin levels. Insulin resistance was calculated by the homeostasis model assessment (HOMA-IR).Results:LVM measurements were higher in both NAFLD and non-NAFLD obese patients in comparison with the lean children. The NAFLD group had significantly higher LVM measurements than the non-NAFLD and lean groups. Carotid IMT was higher in both the NAFLD and non-NAFLD obese patients in comparison with the lean group. The NAFLD group had significantly higher carotid IMT measurements than the non-NAFLD and lean groups. LVM was positively correlated with HOMA-IR and serum alanine aminotransferase levels in the NAFLD obese group. Carotid IMT was positively correlated with HOMA-IR, serum alanine aminotransferase levels and LVM in the NAFLD obese group.Conclusions:We demonstrated that obese adolescents with NAFLD have increased LVM and carotid IMT and low insulin sensitivity. Obese adolescents with NAFLD and increased carotid IMT may demonstrate a more adverse cardiovascular risk profile and higher LVM. Therefore, assessment of carotid IMT, in addition to echocardiography, may assist in risk stratification in obese adolescents with NAFLD with elevated cardiovascular risk factor levels.

Estimation of the ethanol content in flexible-fuel vehicles (FFVs) has attracted increasing attention given the possibility of a variety of fuel blends, beyond E10 and E85, at the pumping stations. In this paper we develop an ethanol estimation algorithm for FFVs equipped with cylinder pressure sensing and direct injection. The algorithm utilizes the cylinder pressure measurements to infer the charge cooling effect associated to evaporating fuel with various ethanol concentrations [Oliverio et al. (2009)]. The ethanol detection feature using the charge cooling effect is named LHV estimation due to the fact that it relies on the Latent Heat of Vaporization characteristics of the fuel. The LHV estimation is shown to be more robust to fuel injector drifts than the traditional ethanol content estimation based on the stoichiometric air-to-fuel ratio (SAFR) identified through the closed-loop air/fuel regulation using the exhaust gas oxygen (EGO) sensor [Ahn et al. (2010)]. In this paper, a method is presented to enable robust ethanol estimation in the presence of fuel injector drifts by integrating the LHV and SAFR based detection features. Dynamometer testing and simulations of a 2.0L turbocharged spark ignition direct injection (SIDI) engine has demonstrated the feasibility of implementing the proposed method at specific operation conditions.

Objective: The aim was to investigate the effect of mechanical vibration on root resorption with or without orthodontic force application. Material and methods: Twenty patients who required maxillary premolar extractions as part of orthodontic treatment were randomly divided into two groups of 10: no-force group and force group. Using a split-mouth procedure, each patient’s maxillary first premolar teeth were randomly assigned as either vibration or control side for both groups. A buccally directed vibration of 50 Hz, with an Oral-B HummingBird device, was applied to the maxillary first premolar for 10 min/day for 12 weeks. After the force application period, the maxillary first premolars were extracted and scanned with micro-computed tomography. Fiji (ImageJ), performing slice-by-slice quantitative volumetric measurements, was used for resorption crater calculation. Total crater volumes were compared with the Wilcoxon and Mann–Whitney U tests. Results: The total crater volumes in the force and no-force groups were 0.476 mm3and 0.017 mm3on the vibration side and 0.462 mm3and 0.031 mm3on the control side, respectively. There was no statistical difference between the vibration and control sides (P> 0.05). There was more resorption by volume in the force group when compared to the no-force group (P&lt; 0.05). Conclusion: Mechanical vibration did not have a beneficial effect on reducing root resorption; however, force application caused significant root resorption.