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The influence of notches and fatigue on the ultimate tensile strength and elongation at break of aluminium alloys (2024-T3, 6061-T4, 6061-T4 uncoated, 6061-T6 uncoated, 7075-T0, and 7076-T6) is presented in this study. A total of 120 specimens were used. On all specimens, notches were made using a CNC machine, with 60 of them subjected to low-cycle fatigue (LCF) before undergoing the tensile test. Based on the statistical examination of the measured data, mathematical prediction models have been established. Compared to their unscratched counterparts, the results indicate a significant decrease in the UTS and elongation at break for both notched and notched-fatigued specimens. The LCF pre-treatment contributes to the negative impacts of the notches, resulting in reduced values for the UTS and elongation at break, thus concluding that surface integrity is critical for maintaining the structural strength of aircraft components.

A new Mg-Zn-Zr-Ca alloy in a powder state, intended to be used for custom shaped implants, was obtained via a mechanical alloying method from pure elemental powder. Further, the obtained powder alloy was processed by a PBF-LB/M (powder bed fusion with laser beam/of metal) procedure to obtain additive manufactured samples for small biodegradable implants. A series of microstructural, mechanical and corrosion analyses were performed. The SEM (scanning electron microscopy) analysis of the powder alloy revealed a good dimensional homogeneity, with a uniform colour, no agglutination and almost rounded particles, suitable for the powder bed fusion procedure. Further, the PBF-LB/M samples revealed a robust and unbreakable morphology, with a suitable porosity (that can reproduce that of cortical bone) and without an undesirable balling effect. The tested Young’s modulus of the PBF-LB/M samples, which was 42 GPa, is close to that of cortical bone, 30 GPa. The corrosion tests that were performed in PBS (Phosphate-buffered saline) solution, with three different pH values, show that the corrosion parameters have a satisfactory evolution comparative to the commercial ZK 60 alloy.

This review focuses on the complex connections between machine learning, mechatronics, and stretch forming, offering valuable insights that can lay the groundwork for future research. It provides an overview of the origins and fundamentals of these fields, emphasizes notable progress, and explores the influence of these fields on society and industry. Also highlighted is the progress of robotics research and particularities in the field of sheet metal forming and its various applications. This review paper focuses on presenting the latest technological advancements and the integrations of these fields from their beginnings to the present days, providing insights into future research directions.

To address diverse challenges and accelerate the adoption of PV technology, innovative and cost-effective PV assemblies are essential. The Analysis of Interconnected Decision Areas—the AIDA method—offers a promising approach to achieving this goal by providing a structured framework for identifying, assessing, and optimizing the design of PV assemblies. The aim is to demonstrate how AIDA can be effectively used to identify and assess potential improvements in PV assembly design, leading to the development of more efficient, cost-effective, and environmentally friendly PV systems. For this, out of 54 combinations, 10 of them were retained, so that in the end only two possible solutions obtained by applying AIDA remained. Both structures were assessed by applying FEM, analysing data regarding equivalent von Mises stresses and displacements but also the existence of stress hotspots. A design insight study was also carried out. Also, the models were first built by additive manufacturing (3D printing). These models were evaluated by a manufacturer so that the evaluation matrix and criteria satisfaction matrix could be successfully completed. Therefore, AIDA can be successfully used in solving problems in product design in the field of mounting structures for PV panels. Depending on the manufacturer’s capabilities, the intended functions can be adapted quickly, because AIDA is quite simple to apply if the data of the problem are known very well. Following the application of the FEM it was concluded that the surfaces as simple as possible are to be followed in the design of components. Also, an assessment of environmental impact was successfully undertaken by means of software assistance. The decision to use one option or another is a subjective one. If the technical data are followed, then one type of structure is the one that the manufacturer should adopt as a solution to the problem. However, if the manufacturer considers that the impact on the environment is important and dedicates resources in this direction, then a different type of structure should be adopted.

IntroductionNatural killer (NK) cells are key anti-tumor effectors of the innate immunity. Phenotypic differences allow us to discriminate in between three functional stages of maturation, named immature, mature and hypermature that are distinctive in terms of receptor expression, cytokine secretion, cytotoxic properties and organ trafficking. NKs display an impressive repertoire of highly polymorphic germline encoded receptors that can be either activating, triggering the effector’s function, or inhibitory, limiting the immune response. In our study, we have investigated peripheral blood NK cells of acute myeloid leukemia (AML) patients.MethodsThe Killer Immunoglobulin-like receptors (KIRs) and the HLA-C genotypes were assessed, as HLA-C molecules are cognate antigens for inhibitory KIRs.ResultsThe AA mainly inhibitory KIR haplotype was found in a higher proportion in AML, while a striking low frequency of the 2DS3 characterized the mainly activating Bx haplotype. Flow cytometry immunophenotyping evidenced a lower overall count of NK cells in AML versus healthy controls, with lower percentages of the immature and mature subpopulations, but with a markedly increase of the hypermature NKs. The analysis of the KIR2DL1, KIR2DL2, KIR2DL3, KIR3DL1, and NKG2A inhibitory receptors surface expression revealed a remarkable heterogeneity. However, an overall trend for a higher expression in AML patients could be noticed in all maturation subpopulations. Some of the AML patients with complex karyotypes or displaying a FLT3 gene mutation proved to be extreme outliers in terms of NK cells percentages or inhibitory receptors expression.DiscussionWe conclude that while the genetic background investigation in AML offers important pieces of information regarding susceptibility to disease or prognosis, it is flow cytometry that is able to offer details of finesse in terms of NK numbers and phenotypes, necessary for an adequate individual evaluation of these patients.

Saliva is a biofluid that reflects general health and that can be collected in order to evaluate and determine various pathologies and treatments. Biomarker analysis through saliva sampling is an emerging method of accurately screening and diagnosing diseases. Anti-epileptic drugs (AEDs) are prescribed generally in seizure treatment. The dose–response relationship of AEDs is influenced by numerous factors and varies from patient to patient, hence the need for the careful supervision of drug intake. The therapeutic drug monitoring (TDM) of AEDs was traditionally performed through repeated blood withdrawals. Saliva sampling in order to determine and monitor AEDs is a novel, fast, low-cost and non-invasive approach. This narrative review focuses on the characteristics of various AEDs and the possibility of determining active plasma concentrations from saliva samples. Additionally, this study aims to highlight the significant correlations between AED blood, urine and oral fluid levels and the applicability of saliva TDM for AEDs. The study also focuses on emphasizing the applicability of saliva sampling for epileptic patients.

To make the most accurate behavioral assessments of mechanical parts, engineers rely heavily on numerous software solutions. These software solutions are able to solve more or less complex problems with a fairly high degree of accuracy and similarity to physical experiments. The common feature of these software solutions is that they need generous resources from the computer on which they are installed. Can't it be done differently? One possible answer may be the use of cloud-based solutions. The main purpose of this paper is to make a comparison and find the limitations of such a solution relative to the established ones in the field of finite element analysis. Therefore, this paper is a case study in which an industrial component – beam bracket – is subjected to a structural analysis on three different software solutions. The reference systems are: ANSYS, a solution dedicated to finite element analysis and SolidWorks Simulation, a solution often used in industry for the assessment of mechanical structures. The cloud-based solution is SimScale, a software product based on open-source codes: Code_Aster and CalculiX.

Self-adaptive mechanisms are gaining momentum in industrial processes. It is understandable that as the complexity increases, the human work must be augmented. Considering this, the authors have developed one such solution for the punch-forming process, using additive manufacturing, i.e., a 3D-printed punch, to draw into shape 6061-T6 aluminum sheets. This paper aims to highlight the topological study used to optimize the punch form shape, the methodology of the 3D printing process, and the material used. For the adaptive algorithm, a complex Python-to-C++ bridge was created. It was necessary as the script has computer vision (used for calculating stroke and speed), punch force, and hydraulic pressure measurement capabilities. The algorithm uses the input data to control its subsequent actions. Two approaches are used in this experimental paper, a pre-programmed direction and an adaptive one, for comparison purposes. The results, namely the drawing radius and flange angle, were statistically analyzed using the ANOVA methodology for significance. The results indicate significant improvements when using the adaptive algorithm.

The objective of this review is to summarize specialty data regarding possible manifestations of diffuse idiopathic skeletal hyperostosis in general otorhinolaryngology practice in order to increase awareness of this entity. Research on the topic was based on consulting specialty books, electronic databases like PubMed, Scopus (Elsevier), Web of Science, Research Gate, Up-to-date and also, on clinical experience. Even though asymptomatic in most patients and many times found during cervical pain investigations or by accident, this overlooked disorder, in rare cases, may cause two of the main complains in practice, dysphagia and dyspnea.

The immunomodulatory effect of a novel biomaterial obtained through electrospinning, based on polylactic acid (PLA) and nano-hydroxyapatite (nano-HAP), loaded with doxycycline (doxy) was evaluated in an animal model. The treatment capabilities as a local non-surgical treatment of periodontitis was investigated on the lower incisors of Wistar rats, after the induction of localized periodontitis using the ligature technique. Following the induction of the disease, the non-surgical treatment of scaling and root planing was applied, in conjunction with the application of the new material. The results of the treatment were evaluated clinically, using the tooth mobility and gingival index scores, as well as histologically. The salivary concentrations of matrix metalloproteinase 8 (MMP-8) and plasmatic concentrations of interleukin 1 (IL-1), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) were also monitored. Two weeks after the ligature application, the periodontal disease was successfully induced in rats. The application of the novel biomaterial obtained through electrospinning was proven to be more effective in improving the clinical parameters, while decreasing the salivary MMP-8 and plasmatic IL-1 and TNF-α concentrations, compared to the simple scaling and root planing. Thus, the novel electrospun biomaterial could be a strong candidate as an adjuvant to the non-surgical periodontal therapy.

Mucoadhesive films loaded with doxycycline hyclate (Doxy Hyc), consisting of mixtures of hydroxypropylmethyl cellulose (HPMC) E3, K4 and polyacrylic acid (Carbopol 940), were prepared by casting method, aiming to design a formulation intended for application in the oral cavity. The obtained film formulations exhibited a Doxy Hyc content between 7.52 ± 0.42 and 7.83 ± 0.41%, which had adequate mechanical properties for application in the oral cavity and pH values in the tolerance range. The x-ray diffraction studies highlighted the amorphisation of Doxy Hyc in the preparation process and the antibiotic particles present on the surface of the films, identified in the TEM images, which ensured a burst release effect in the first 15 min of the in vitro dissolution studies, after which Doxy Hyc was released by diffusion, the data presenting a good correlation with the Peppas model, n < 0.5. The formulation F1, consisting of HPMC K4 combined with C940 in a ratio of 5:3, the most performing in vitro, was tested in vivo in experimentally-induced periodontitis and demonstrated its effectiveness in improving the clinical parameters and reducing the salivary levels of matrix metalloproteinase-8 (MMP-8). The prepared Doxy Hyc loaded mucoadhesive buccal film could be used as an adjuvant for the local treatment of periodontitis, ensuring prolonged release of the antibiotic after topical application.

The present paper is presenting a case study of a rescue archaeological investigation following the building of a motorway. The research area revealed the civilian baths complex of the Roman auxiliary fort of Optatiana in the province of Dacia (today, Sutor, Sălaj County, Romania). The analysis of coin finds, issuers, types, denominations, within the archaeological contexts they were found in, reveal the fact that only one-two coins may lead the archaeologist into a chronological pitfall, while a group of more than five single finds with similar dating elements (e.g. same issuer or his successor(s) from the same context/phase may be a true help in understanding the development of an archaeological complex.

The present study aimed to assess the in vitro antimicrobial effects of a novel biomaterial containing polylactic acid (PLA), nano-hydroxyapatite (nano-HAP) and Doxycycline (Doxy) obtained by electrospinning and designed for the non-surgical periodontal treatment. The antimicrobial activity of two samples (test sample, PLA-HAP-Doxy7: 5% PLA, nano-HAP, 7% Doxy and control sample, PLA-HAP: 5% PLA, nano-HAP) against two periodontal pathogens—Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis—was assessed using the Kirby–Bauer Disk Diffusion Susceptibility Test and compared with the effect of four antibiotics used as adjuvants in periodontal therapy: Amoxicillin, Ampicillin, Doxy and Metronidazole. The test sample (embedded with Doxy) showed higher inhibitory effects than commonly used antibiotics used in the treatment of periodontitis, while the control sample showed no inhibitory effects. Moreover, significant differences were observed between the inhibition zones of the two samples (p < 0.05). The Doxy-loaded PLA nanofibres had an antimicrobial effect against the periodontal pathogens. Based on these results, the novel biomaterial could be a promising candidate as adjuvant for the non-surgical local treatment in periodontitis.

New products based on a structure that represents a combination of known elements in a higher quality set, as well as products that refer to new shapes, new curves, new surfaces can be obtained logically - analytically - deductively or by methods specific to the optimal calculation. The present paper focuses on the method of analyzing tridimensional morphology, some possible solutions being evaluated on value criteria. Of course, these methods can be applied in the field of engineering with very good results. The focus of this study is to obtain new thin walled tubular structures - such as car crash members - which in the case of axial shock loads have a higher predictable behavior compared to those already used in various technical fields. Following the study, it can be said that depending on the amount of absorbed energy in the case of axial collisions and the absorption of kinetic energy developed at the time of impact, the optimal crashworthiness solution could be tubular structures with a circular support base and rectangular deformable area for impact.

Introduction. MRgFUS is a novel technology, which can have profound implications in the current treatment of neurological disorders. Its applications range widely, from the alteration of the blood-brain barrier, ablation of tumours to the treatment of movement disorders. Objective. To review, following thorough research of the literature, the principles of its use in the treatment of neurological diseases and the main reported evidence of its clinical implementation. Material and method. Interrogation of the MEDLINE database, using the PubMed search engine, for the following MESH words: “MRgFUS”, “FUS” “BRAIN”, from 2000 to the current year. Conclusion. MRgFUS can be safely used today for the treatment of Essential Tremor. New research is warranted for the evaluation of its safety and effectiveness in other neurological disorders.

Even though they initially appeared as a method of using waste from other production processes, tailored welded blanks (TWB) presented several advantages by combining materials with different characteristics. On the one hand, this study focuses on minimizing the adverse effects caused by the springback of TWB parts. The proposed method is based on the Taguchi technique using orthogonal type 23 networks. On the other hand, genetic algorithms were applied to obtain maximum performance parameters within the dynamic loadings of tubular structures made of TWB by advantageous positioning of the weld line. The obtained data were compared and evaluated through software platforms such as MATLAB, Design Expert, and Dynaform, and experimental validation. By generating an objective function, the construction of thin-walled tubular structures can be controlled for a predetermined deformation and maximum energy absorption. The data obtained has an error rate of less than 3%, thus considering that this method can be used successfully in the qualitative and quantitative estimation of dynamically loaded TWB tubular structures.

Natural killer (NK) cells are key innate immunity effectors that play a major role in malignant cell destruction. Based on expression patterns of CD16, CD56, CD57, and CD94, three distinct NK cell maturation stages have been described, which differ in terms of cytokine secretion, tissue migration, and the ability to kill target cells. Our study addressed NK cell maturation in bone marrow under three conditions: a normal developmental environment, during pre-leukemic state (myelodysplastic syndrome, MDS), and during leukemic transformation (acute myeloblastic leukemia, AML). In this study, we used a new tool to perform multicolor flow cytometry data analysis, based on principal component analysis, which allowed the unsupervised, accurate discrimination of immature, mature, and hypermature NK subpopulations. An impaired NK/T cell distribution was observed in the MDS bone marrow microenvironment compared with the normal and AML settings, and a phenotypic shift from the mature to the immature state was observed in NK cells under both the MDS and AML conditions. Furthermore, an impaired NK cell antitumor response, resulting in changes in NK cell receptor expression (CD159a, CD158a, CD158b, and CD158e1), was observed under MDS and AML conditions compared with the normal condition. The results of this study provide evidence for the failure of this arm of the immune response during the pathogenesis of myeloid malignancies. NK cell subpopulations display a heterogeneous and discordant dynamic on the spectrum between normal and pathological conditions. MDS does not appear to be a simple, intermediate stage but rather serves as a decisive step for the mounting of an efficient or ineffective immune response, leading to either the removal of the tumor cells or to malignancy.

Methods and techniques to stimulate creativity are indispensable in the process of obtaining more reliable and competitive products. For the elaboration and efficient use of logical-deductive methods and techniques in creativity, it is necessary to know a minimum of combinatorics, which include arrangements, combinations, permutations, graphs and finite networks. From the multitude of methods of orderly enumeration of all ensembles, without omissions or repetitions, the lexicographic method is recommended, according to which, the assemblies are ordered in ascending order according to the sum of the component elements index. The main purpose of this paper is to apply the lexicographic method to obtain a more efficient flow faucet body in terms of working fluid behavior. Thus, the pressure, flow, velocity variation and degree of fluid vorticity have better values for the faucet body obtained by applying the lexicographic method. Therefore, by applying the flow simulation method, it was possible to characterize the behavior of the working fluid.

Periodic removal of sediment from aquaculture ponds is practiced to maintain their productivity and animal welfare. The recovery of sediment as a plant fertilizer could alleviate the costs of sediment removal. The objective of this study was to test the effects of a dried sediment, extracted from an aquaculture pond used for common carp cultivation, on the growth and physiology of potted wheat grass and the quality of the juice obtained from wheat grass. The results showed that sediment application did not produce significant morphological changes, although the values for plant height (16.94–19.22 cm), leaf area (19.67–139.21 mm2), and biomass (3.39–4.26 g/plant) were higher in sediment-grown plants. However, at a physiological level, the effect was negative, decreasing photosynthesis (0.82–1.66 μmol CO2 m2s−1), fluorescence ΦPSII (0.737–0.782), and chlorophyll content (1.40–1.83 CCI). The juice yield was reduced in the sediment treatments (46–58 g/100 g), while the quality was improved by increasing the content of phenols (2.55–3.39 µg/mL gallic acid equivalent), flavonoids (1.41–1.85 µg/mL quercetin equivalent), and antioxidant activity (47.99–62.7% inhibition of; 2,2-diphenyl-1-picrylhydrazyl). The positive results obtained in this study can be attributed to the moderate nutrient content of the sediment and a negligible concentration of heavy metals.

Most technological manufacturing lines include hydraulically operated stationary tools, devices and equipment. During a manufacturing cycle, there are phases, usually short, in which part of the hydraulic cylinders of the drive systems concerned, with small gauges and displacement speeds, have to generate / maintain high clamping or pressing forces, which implies functioning at high working pressures. The solution for such cylinders is to use modular hydraulic pumping units comprising: oil tank; low-pressure electric pump; hydraulic directional valve for starting, stopping and changing the direction of displacement of the cylinder; electric pump pressure control valve; pressure filter; return filter; oscillating hydraulic pressure intensifier (minibooster mounted directly on the cylinder). Such pumping units, which consume low pressure (in the primary side of the minibooster) to generate high pressure (in the secondary side of the minibooster), are cost-effective when it comes to the procurement of components, installing them, the space required for installation, and their maintenance, too. The classic applications of using them are for achieving and maintaining high pressure values, either in volumes of closed spaces (endurance tests on pipes and tanks), or at the active stroke end of hydraulic cylinders (hydraulic presses). The authors demonstrate, on a laboratory test bench, the following: - The range of applications of such pumping units can be extended in a third direction, namely for actuation of hydraulic cylinders with low gauge / speeds and constant high load (high working pressure) over the entire stroke; - The uniformity of displacement of these cylinders with load over the entire stroke, fed and actuated by such pumping units, is weakly affected by the pulsating mode of operation of the hydraulic pressure intensifier.

An industrial process is defined through its quality of parts and their production costs. Labour-intensive operations must be applied to produce high-quality components with inexpensive resources. Recent development in dedicated software allows the industrial sector to rely on more and more autonomous solutions to obtain an optimum ratio between part quality and cost. The stretch forming process is an operation that has a high degree of difficulty, due to the process parameters and the spring-back effect of materials. Our approach to solving several of the shortcomings of this process was to develop a self-adaptive algorithm with computer vision capabilities that adapts to the process in real-time. This experimental study highlights the results obtained using this method, as well as a comparison to a classical method for the stretch-forming process (SFP). The results have noted that the stretch-forming algorithm improves the process, while adapting its decisions with each step.

The purpose of this article is twofold – on the one hand, it offers an overview of the main theoretical orientations of libertarianism, with a focus on right-libertarianism, and its potential support for a universal basic income guarantee; on the other hand, it looks at what seems the most developed case in the right-libertarian camp for such a scheme. Although sympathetic to Zwolinski’s arguments, I contend that a neo-Lockean framework cannot conduce to a basic income institutional arrangement without an interpretation of the Lockean proviso in a left-libertarian manner and the most promising strategy for a right-libertarian argument would be one carried in other frameworks.

Shockwave therapy is a noninvasive treatment technique used in multidisciplinary fields, such as sports medicine, physical therapy, and orthopedics. This method of treatment is recommended for medical conditions, such as muscle contractions, intramuscular hematoma, or Dupuytren’s contracture. The shockwaves are high-energy pressure waves characterized by nonlinearity, high frequency, and peak pressure followed by low-pressure amplitude which are transmitted through an applicator to the affected tissue. In the case of spinal muscles, the conventional applicator can only be used on one side of the spinal cord at a time. Taking this into consideration, the approach suggested in this paper involves the design of a dedicated dual-tip applicator. This process implied predesign, finite element analysis, statistical analysis of the data, and optimization. We analyzed the input factors, such as frequency, pressure, applicator tip distance, shape, flatness, and material along with their effects, namely induced stress, tissue contact pressure, total strain energy, and propagation velocity. The proposed final design of the applicator uses geometric features suggested by the optimization analysis and also mechanical design features.

Background: Saliva has been recently proposed as an alternative to classic biofluid analyses due to both availability and reliability regarding the evaluation of various biomarkers. Biosensors have been designed for the assessment of a wide spectrum of compounds, aiding in the screening, diagnosis, and monitoring of pathologies and treatment efficiency. This literature review aims to present the development in the biosensors research and their utility using salivary assessment. Methods: a comprehensive literature search has been conducted in the PubMed database, using the keywords “saliva” and “sensor”. A two-step paper selection algorithm was devised and applied. Results: The 49 papers selected for the present review focused on assessing the salivary biomarkers used in general diseases, oral pathologies, and pharmacology. The biosensors proved to be reliable tools for measuring the salivary levels of biochemical metabolic compounds such as glucose, proteinases and proteins, heavy metals and various chemical compounds, microorganisms, oncology markers, drugs, and neurotransmitters. Conclusions: Saliva is a biofluid with a significant clinical applicability for the evaluation and monitoring of a patient’s general health. Biosensors designed for assessing a wide range of salivary biomarkers are emerging as promising diagnostic or screening tools for improving the patients’ quality of life.

Guy Halsall, Worlds of Arthur. Facts and Fictions of the Dark Ages, Oxford: University Press, 2014. 384 pp. (20 black and white halftones, 15 maps) ISBN 978–0–19–965817–6