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The objective of the study was to determine the minimum thickness of a thin wall for milling at a maximized axial depth of cut, considering the effect of cutting speed on residual stress and post-machining distortion. Test samples were made of aluminum alloy 7050 T7451. The milling operation at a maximized axial depth of cut was performed during finishing. Response surface methodology was employed. Wall thickness and cutting speed were considered as two independent variables, while dependent variables were flatness deviation, wall thickness deviation, and residual stress. Flatness deviation and wall thickness deviation were used as the indicators of post-machining wall deformation and their measurements were made using a coordinate measuring machine. Residual stress was measured with an X-ray diffractometer. The obtained results showed that thin wall milling at a maximized axial depth of cut was feasible; nevertheless, for a wall thickness of t = 1 mm, the formation of considerable post-machining deformation was observed. Therefore, for milling with the employed axial depth of cut, the wall thickness should be t ≥ 1.5 mm. The highest strain and residual stress were observed at vc ≈ 600 m/min; despite its subsequent decrease, the strain at vc = 900 m/min was still higher than that at vc = 300 m/min. The results also showed tensile stress to be dominant, while compressive stress only occurred at vc = 300 m/min for wall thicknesses of t = 1.5 mm and t = 2 mm. The developed response surface quadratic models make it possible to predict the tested variables under similar conditions.

This paper reports the results of a study examining the effect of thermomechanical interactions that occur during a milling process conducted at a maximum axial depth of cut for a thin wall made of aluminium alloy 7050 T7451. The impact of cutting speed and wall thickness on cutting force and cutting temperature was determined. Response surface methodology and face-centred central composite design were used. It was found that raising the cutting speed to approximately vc ≈ 700 m/min led to an increase in cutting force component Fx and cutting temperature T, followed by a decrease in their values. Nonetheless, the values of these variables were considerably higher than those observed at vc = 300 m/min. The thinnest tested wall of t = 1 mm exhibited the greatest process instability and evident signs of chatter, while a wall thickness increase to t = 2 mm resulted in improved process stability and reduced flatness deviation. The interaction between the cutting force and the cutting temperature, as well as the occurrence of chatter, were established as two dominant factors affecting thin wall machining accuracy. Results showed that the assumed empirical models could be used to predict the tested dependent variables under similar milling conditions.

Philadelphia-negative myeloproliferative neoplasms (MPNs) are a diverse group of diseases whose common feature is the presence of V617F mutation of the JAK2 gene. In the era of novel therapeutic strategies in MPNs, such as JAK-inhibitor therapy, there is a growing need for establishing high sensitive quantitative methods, which can be useful not only at diagnosis but also for monitoring therapeutic outcomes, such as minimal residual disease (MRD). In this study, we compared the qPCR and ddPCR methods and their clinical utility for diagnosis, prognostication, and treatment monitoring of MPNs with JAK2 V617F mutation in 63 MPN patients of which 6 were subjected to ruxolitinib treatment. We show a high conformance between the two methods (correlation coefficient r = 0.998 (p < 0.0001)). Our experiments revealed high analytical sensitivity for both tests, suggesting that they are capable of detecting the JAK2 V617F mutation at diagnosis of MPN with a limit of detection (LoD) of 0.12% for qPCR and 0.01% for ddPCR. The alterations of JAK2 V617F allele burden in patients treated with ruxolitinib were measured by both methods with equal accuracy. The results suggest an advantage of ddPCR in monitoring MRD because of allele burdens below the LoD of qPCR. Overall, the clinical utility of qPCR and ddPCR is very high, and both methods could be recommended for the routine detection of the V617F mutation at diagnosis, though ddPCR will probably supersede qPCR in the future due to cost-effectiveness.

This study aimed to investigate the association between selected variants of genes related to dopamine metabolism pathways and the risk of and progression of Parkinson’s disease (PD). This prospective cohort study was conducted in one academic teaching hospital. The study was conducted on 126 patients diagnosed with idiopathic Parkinson’s disease. Blood samples were collected to conduct a genotyping of MAOB, DRD1, DRD2, and DDC genes. Genotype and allele frequencies of MAOB (rs1799836) variants were not associated with the course of PD. Genotype and allele frequencies of DRD2 (rs2283265) variants were associated with risk of dementia (p = 0.001) and resulted in parts II and III of the UPDRS scale (p = 0.001). Genotype and allele frequencies of DRD2 (rs1076560) variants were associated with risk of dementia (p = 0.001) and resulted in parts II and III of the UPDRS scale (p = 0.001). Genotype and allele frequencies of DDC (rs921451) variants were not associated with the course of PD.

The aim of this study is to investigate the impact of machining parameters on the deflection of a cutting tool (i.e., end mill) in the milling of a surface with a curvilinear profile. Test samples were made of aluminium alloy EN AW-7075 T651. Experiments were conducted using the Gocator 2530 laser line profile sensor for real-time measurement of dynamic tool displacement with an inspection speed up to 10 kHz at resolution ranging from 0.028 to 0.054 mm. Response surface methodology was used. Five main technological factors were analysed: cutting speed, feed per tooth (cutting parameters), amplitude, term (curvilinear profile parameters), and the number of flutes (end mill parameter). Obtained data were filtered and visualised as 3D plots. The results showed that cutting speed and amplitude had the greatest impact on tool deflection, while feed per tooth also played a significant role in process stability. In particular, the use of tools with a higher number of flutes led to a considerable reduction in tool deflection, confirming their positive effect on the stability of the machining process. These findings may serve as a basis for the optimisation of machining parameters by taking into account the dynamic deformation of cutting tools.

Non-small cell lung cancer is the predominant form of lung cancer and is associated with a poor prognosis. MiRNAs implicated in cancer initiation and progression can be easily detected in liquid biopsy samples and have the potential to serve as non-invasive biomarkers. In this study, we employed next-generation sequencing to globally profile miRNAs in serum samples from 71 early-stage NSCLC patients and 47 non-cancerous pulmonary condition patients. Preliminary analysis of differentially expressed miRNAs revealed 28 upregulated miRNAs in NSCLC compared to the control group. Functional enrichment analyses unveiled their involvement in NSCLC signaling pathways. Subsequently, we developed a gradient-boosting decision tree classifier based on 2588 miRNAs, which demonstrated high accuracy (0.837), sensitivity (0.806), and specificity (0.859) in effectively distinguishing NSCLC from non-cancerous individuals. Shapley Additive exPlanations analysis improved the model metrics by identifying the top 15 miRNAs with the strongest discriminatory value, yielding an AUC of 0.96 ± 0.04, accuracy of 0.896, sensitivity of 0.884, and specificity of 0.903. Our study establishes the potential utility of a non-invasive serum miRNA signature as a supportive tool for early detection of NSCLC while also shedding light on dysregulated miRNAs in NSCLC biology. For enhanced credibility and understanding, further validation in an independent cohort of patients is warranted.

Background Pluripotent stem cells present the ability to self-renew and undergo differentiation into any cell type building an organism. Importantly, a lot of evidence on embryonic stem cell (ESC) differentiation comes from in vitro studies. However, ESCs cultured in vitro do not necessarily behave as cells differentiating in vivo. For this reason, we used teratomas to study early and advanced stages of in vivo ESC myogenic differentiation and the role of Pax7 in this process. Pax7 transcription factor plays a crucial role in the formation and differentiation of skeletal muscle precursor cells during embryonic development. It controls the expression of other myogenic regulators and also acts as an anti-apoptotic factor. It is also involved in the formation and maintenance of satellite cell population. Methods In vivo approach we used involved generation and analysis of pluripotent stem cell-derived teratomas. Such model allows to analyze early and also terminal stages of tissue differentiation, for example, terminal stages of myogenesis, including the formation of innervated and vascularized mature myofibers. Results We determined how the lack of Pax7 function affects the generation of different myofiber types. In Pax7−/− teratomas, the skeletal muscle tissue occupied significantly smaller area, as compared to Pax7+/+ ones. The proportion of myofibers expressing Myh3 and Myh2b did not differ between Pax7+/+ and Pax7−/− teratomas. However, the area of Myh7 and Myh2a myofibers was significantly lower in Pax7−/− ones. Molecular characteristic of skeletal muscles revealed that the levels of mRNAs coding Myh isoforms were significantly lower in Pax7−/− teratomas. The level of mRNAs encoding Pax3 was significantly higher, while the expression of Nfix , Eno3 , Mck , Mef2a , and Itga7 was significantly lower in Pax7−/− teratomas, as compared to Pax7+/+ ones. We proved that the number of satellite cells in Pax7−/− teratomas was significantly reduced. Finally, analysis of neuromuscular junction localization in samples prepared with the iDISCO method confirmed that the organization of neuromuscular junctions in Pax7−/− teratomas was impaired. Conclusions Pax7−/− ESCs differentiate in vivo to embryonic myoblasts more readily than Pax7+/+ cells. In the absence of functional Pax7, initiation of myogenic differentiation is facilitated, and as a result, the expression of mesoderm embryonic myoblast markers is upregulated. However, in the absence of functional Pax7 neuromuscular junctions, formation is abnormal, what results in lower differentiation potential of Pax7−/− ESCs during advanced stages of myogenesis.

The aim of this paper is to analyse the effect of the selected geometric properties of thin-walled structures on post-machining deformations. In the study, EN AW-7075 T651 and EN AW-6082 T651 aluminium alloys were used to prepare specially designed thin-walled sample elements, i.e., elements with walls arranged in a semi-open and closed structure and with a dimension of 165 × 262 × 50.8 mm consisting of bottom and vertical stiffening walls and so-called ribs with a thickness of 1 mm. The measurements of the absolute deformations of the thin-walled bottom were performed with the use of a Vista coordinate-measuring machine by Zeiss with a PH10 head by Renishaw. Based on the obtained results, it was found that absolute deformation values were higher for walls arranged in a semi-open structure. It is related to a lower rigidity of the tested structure resulting from the lack of a stiffening wall, which is the so-called “rib”. Notwithstanding the geometry of the elements, greater absolute deformation values were recorded following conventional cutting methods. The use of high-speed cutting (HSC) provided positive outcomes in terms of minimising the deformation of thin-walled elements. Additionally, it was found that higher absolute deformations were obtained for EN AW-7075 T651 alloy.

The paper presents an evaluation of post-machining deformations of thin-walled elements as regards the mechanical properties of the applied, rolled semi-finished products. Nowadays, wrought aluminum alloys, supplied primarily in the form of rolled plates, are widely applied in the production of thin-walled integral parts. Considering the high requirements for materials, especially in the aviation sector, it is important to be aware of their mechanical properties and for semi-finished products delivered after plastic working to take into account the so-called “technological history” concerning, inter alia, the direction of rolling. The study focused on determining the influence of the ratio of the tension direction to the rolling direction on the selected mechanical properties of the EN AW-2024 T351 aluminum alloy depending on the sample thickness and its relation to the deformation of thin-walled parts. Based on the obtained results, it was found that the sample thickness and the ratio of the tension direction to the rolling direction affected the mechanical properties of the selected aluminum alloy, which in turn translated into post-machining deformations. Summarizing, the textured surface layer had a significant impact on the mentioned deformation. Greater deformations were noted for samples made of a semi-finished product with a thickness of 5 mm in comparison to 12 mm. It was the result of the influence of the surface layer, which at lower thickness had a higher percentage of contents than in thicker samples.

In this study, the correlations between milling conditions—namely, the cutting tool feed direction relative to the rolling direction, the milling type, the coolant application, as well as the cutting speed—and the surface residual stress of a selected aluminum alloy (2024 T351) were investigated. Determining the type and magnitude of residual stress is of paramount importance as this stress is among the primary causes of post-machining strain of thin-walled components. On the basis of the experimental results, it was found that all factors analyzed significantly affect the residual stress state. Specifically, milling in the parallel direction induces lower residual tensile stress compared to milling in the perpendicular direction. Analogously, up-milling yields lower tensile residual stress than down-milling, and flood cooling leads to lower tensile residual stress than MQL. It was clearly confirmed that as cutting speed increases, tensile residual stress also increases, but only up to a certain threshold; once the high-speed cutting regime is reached, tensile residual stress begins to decrease. Consequently, the proper selection of milling parameters is a crucial consideration for optimizing machining processes and minimizing machining-induced residual stress.