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1.
Materials (Basel) ; 16(4)2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36837262

ABSTRACT

Recently, AI has been used in industry for very precise quality control of various products or in the automation of production processes through the use of trained artificial neural networks (ANNs) which allow us to completely replace a human in often tedious work or in hard-to-reach locations. Although the search for analytical formulas is often desirable and leads to accurate descriptions of various phenomena, when the problem is very complex or when it is impossible to obtain a complete set of data, methods based on artificial intelligence perfectly complement the engineering and scientific workshop. In this article, different AI algorithms were used to build a relationship between the mechanical parameters of papers used for the production of corrugated board, its geometry and the resistance of a cardboard sample to edge crushing. There are many analytical, empirical or advanced numerical models in the literature that are used to estimate the compression resistance of cardboard across the flute. The approach presented here is not only much less demanding in terms of implementation from other models, but is as accurate and precise. In addition, the methodology and example presented in this article show the great potential of using machine learning algorithms in such practical applications.

2.
Materials (Basel) ; 16(1)2023 Jan 03.
Article in English | MEDLINE | ID: mdl-36614797

ABSTRACT

The edge crush test is the most popular laboratory test in the corrugated packaging industry. It measures the edge crush resistance of a sample in the cross-fiber direction (CD), also known as the ECT index. This parameter is widely used for the specification of the board by its producers. It is also utilized in most analytical formulas describing the load capacity of the packaging. On the other hand, the ECT value can be estimated from both analytical and numerical models based on the basic parameters of each constituent paper. Knowing the compressive strength in CD (commonly known as SCT) and the elastic properties of the individual layers, the sample geometry (i.e., the period and height of the corrugated layer), as well as the boundary conditions, the ECT value can be calculated. This is very useful as new boards can be virtually analyzed before being manufactured. In this work, both detailed numerical models based on finite elements (FE) methods and very simple analytical (engineering) models were used for the ECT calculations. All presented models were validated with experimental data. The surprising consistency and high precision of the results obtained with the simplest approach was additionally analyzed in the study.

3.
Nat Nanotechnol ; 17(11): 1192-1197, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36138199

ABSTRACT

The MXene family of two-dimensional transition metal carbides and nitrides already includes ~50 members with distinct numbers of atomic layers, stoichiometric compositions and solid solutions, in-plane or out-of-plane ordering of atoms, and a variety of surface terminations. MXenes have shown properties that make them attractive for applications ranging from energy storage to electronics and medicine. Although this compositional variability allows fine-tuning of the MXene properties, it also creates challenges during the analysis of MXenes because of the presence of multiple light elements (for example, H, C, N, O, and F) in close proximity. Here, we show depth profiling of single particles of MXenes and their parent MAX phases with atomic resolution using ultralow-energy secondary-ion mass spectrometry. We directly detect oxygen in the carbon sublattice, thereby demonstrating the existence of oxycarbide MXenes. We also determine the composition of adjacent surface termination layers and show their interaction with each other. Analysis of the metal sublattice shows that Mo2TiAlC2 MAX exhibits perfect out-of-plane ordering, whereas Cr2TiAlC2 MAX exhibits some intermixing between Cr and Ti in the inner transition metal layer. Our results showcase the capabilities of the developed secondary-ion mass spectrometry technique to probe the composition of layered and two-dimensional materials with monoatomic-layer precision.

4.
Sensors (Basel) ; 22(13)2022 Jun 25.
Article in English | MEDLINE | ID: mdl-35808303

ABSTRACT

When producing packaging from corrugated board, material weakening often occurs both during the die-cutting process and during printing. While the analog lamination and/or printing processes that degrade material can be easily replaced with a digital approach, the die-cutting process remains overwhelmingly analog. Recently, new innovative technologies have emerged that have begun to replace or at least supplement old techniques. This paper presents the results of laboratory tests on corrugated board and packaging made using both analog and digital technologies. Cardboard samples with digital and analog creases are subject to various mechanical tests, which allows for an assessment of the impact of creases on the mechanical properties of the cardboard itself, as well as on the behavior of the packaging. It is proven that digital technology is not only more repeatable, but also weakens the structure of corrugated board to a much lesser extent than analog. An updated numerical model of boxes in compression tests is also discussed. The effect of the crushing of the material in the vicinity of the crease lines in the packaging arising during the analog and digital finishing processes is taken into account. The obtained enhanced computer simulation results closely reflect the experimental observations, which prove that the correct numerical analysis of corrugated cardboard packaging should be performed with the model taking into account the crushing.


Subject(s)
Product Packaging , Computer Simulation
5.
Materials (Basel) ; 15(6)2022 Mar 15.
Article in English | MEDLINE | ID: mdl-35329601

ABSTRACT

Designing corrugated board packaging is a real challenge, especially when the packaging material comes from multiple recycling. Recycling itself is a pro-ecological and absolutely necessary process, but the mechanical properties of materials that are processed many times deteriorate with the number of cycles. Manufacturers are trying to use unprecedented design methods to preserve the load-bearing capacity of packaging, even when the material itself is of deteriorating quality. An additional obstacle in the process of designing the structure of paper packaging is the progressive systematic reduction of the grammage (the so-called lightweight process) of corrugated cardboard. Therefore, this research presents a critical look at the process of optimal selection of corrugated cardboard for packaging structures, depending on the paper used. The study utilizes analytical, simplified formulas to estimate the strength of cardboard itself as well as the strength of packaging, which are then analyzed to determine their sensitivity to changes in cardboard components, such as the types of paper of individual layers. In the performed sensitivity analysis, numerical homogenization was used, and the influence of initial imperfections on the packaging mechanics was determined. The paper presents a simple algorithm for the optimal selection of the composition of corrugated cardboard depending on the material used and the geometry of the packaging, which allows for a more conscious production of corrugated cardboard from materials derived, e.g., from multiple recycling.

6.
Materials (Basel) ; 15(3)2022 Jan 18.
Article in English | MEDLINE | ID: mdl-35160666

ABSTRACT

The optimal selection of the composition of corrugated cardboard dedicated to specific packaging structures is not an easy task. The use of lighter boards saves material, but at the same time increases the risk of not meeting the guaranteed load capacity. Therefore, the answer to the question "in which layer the basis weight of the paper should be increased?" is not simple or obvious. The method proposed here makes it easy to understand which components and to what extent they affect the load-bearing capacity of packages of various dimensions. The use of numerical homogenization allows for a quick transformation of a cardboard sample, i.e., a representative volume element (RVE) into a flat plate structure with effective parameters describing the membrane and bending stiffness. On the other hand, the use of non-local sensitivity analysis makes it possible to find the relationship between the parameters of the paper and the load capacity of the packaging. The analytical procedures presented in our previous studies were used here to determine (1) the edge crush resistance, (2) critical load, and (3) the load capacity of corrugated cardboard packaging. The method proposed here allows for obtaining a comprehensive and hierarchical list of the parameters that play the most important role in the process of optimal packaging design.

7.
Materials (Basel) ; 15(2)2022 Jan 16.
Article in English | MEDLINE | ID: mdl-35057380

ABSTRACT

Bending stiffness (BS) is one of the two most important mechanical parameters of corrugated board. The second is edge crush resistance (ECT). Both are used in many analytical formulas to assess the load capacity of corrugated cardboard packaging. Therefore, the correct determination of bending stiffness is crucial in the design of corrugated board structures. This paper focuses on the analytical determination of BS based on the known parameters of the constituent papers and the geometry of the corrugated layers. The work analyzes in detail the dependence of the bending stiffness of an asymmetric, five-layer corrugated cardboard on the sample arrangement. A specimen bent so that the layers on the lower wave side are compressed has approximately 10% higher stiffness value. This is due to imperfections, which are particularly important in the case of compression of very thin liners. The study showed that imperfection at the level of a few microns causes noticeable drops in bending stiffness. The method has also been validated by means of experimental data from the literature and simple numerical finite element model (FEM). The obtained compliance of the computational model with the experimental model is very satisfactory. The work also included a critical discussion of the already published data and observations of other scientists in the field.

8.
Cent European J Urol ; 74(3): 422-428, 2021.
Article in English | MEDLINE | ID: mdl-34729232

ABSTRACT

INTRODUCTION: The aim of this article was to evaluate non-invasive tests, which were typically used in preoperative diagnosis of male patients with anterior urethral strictures in the assessment of the urethral resistance caused by urethral occlusion. MATERIAL AND METHODS: A total of 63 adult males with confirmed urethral stricture and aged below 55 years old were enrolled in the study. Data obtained from non-invasive tests such as uroflowmetry (UF), ultrasound examination (USG), and questionnaires such as from The International Prostatic Symptom Score (IPSS), and The Patient-Reported Outcome Measure for Urethral Stricture Surgery (USS-PROM) were analyzed. RESULTS: Among all analyzed non-invasive tests, bladder wall thickness (BWT) showed the highest correlation with the degree of urethral occlusion described as percentage of preserved urethral lumen (r = -0.70; p <0.0001). UF variables presented medium degree of correlation, with maximum flow rate (Qmax) as the best parameter (p = 0.45; p = 0.0005). Results from both questionnaires did not show any correlation with the severity of the urethral stricture. Multiple linear regression analysis showed that only BWT was an independent predictor in detection degree of urethral occlusion. CONCLUSIONS: UF and USG seem to be useful additional diagnostic tools in assessment severity of urethral occlusion in men suffering from anterior urethral stricture. Among them, USG had the highest correlation with degree of urethral occlusion.

9.
Materials (Basel) ; 14(19)2021 Oct 02.
Article in English | MEDLINE | ID: mdl-34640164

ABSTRACT

The standard edge crush test (ECT) allows the determination of the crushing strength of the corrugated cardboard. Unfortunately, this test cannot be used to estimate the compressive stiffness, which is an equally important parameter. This is because any attempt to determine this parameter using current lab equipment quickly ends in a fiasco. The biggest obstacle is obtaining a reliable measurement of displacements and strains in the corrugated cardboard sample. In this paper, we present a method that not only allows for the reliable identification of the stiffness in the loaded direction of orthotropy in the corrugated board sample, but also the full orthotropic material stiffness matrix. The proposed method uses two samples: (a) traditional, cut crosswise to the wave direction of the corrugated core, and (b) cut at an angle of 45°. Additionally, in both cases, an optical system with digital image correlation (DIC) was used to measure the displacements and strains on the outer surfaces of samples. The use of a non-contact measuring system allowed us to avoid using the measurement of displacements from the crosshead, which is burdened with a large error. Apart from the new experimental configuration, the article also proposes a simple algorithm to quickly characterize all sought stiffness parameters. The obtained results are finally compared with the results obtained in the homogenization procedure of the cross-section of the corrugated board. The results were consistent in both cases.

10.
Materials (Basel) ; 14(18)2021 Sep 09.
Article in English | MEDLINE | ID: mdl-34576402

ABSTRACT

In the modern world, all manufacturers strive for the optimal design of their products. This general trend is recently also observed in the corrugated board packaging industry. Colorful prints on displays, perforations in shelf-ready-packaging and various types of ventilation holes in trays, although extremely important for ergonomic or functional reasons, weaken the strength of the box. To meet the requirements of customers and recipients, packaging manufacturers outdo each other with new ideas for the construction of their products. Often the aesthetic qualities of the product become more important than the attention to maintaining the standards of the load capacity of the packaging (which, apart from their attention-grabbing functions, are also intended to protect transported products). A particular flaps design (both top and bottom) and its influence on the strength of the box are investigated in this study. An updated analytical-numerical approach is used here to predict the strength of packaging with various flap offsets. Experimental results indicated a significant decrease in the static load-bearing capacity of packaging in the case of shifted flap creases. The simulation model proposed in our previous work has been modified and updated to take into account this effect. The results obtained by the model presented in this paper are in satisfactory agreement with the experimental data.

11.
Materials (Basel) ; 14(14)2021 Jul 06.
Article in English | MEDLINE | ID: mdl-34300705

ABSTRACT

The corrugated board packaging industry is increasingly using advanced numerical tools to design and estimate the load capacity of its products. This is why numerical analyses are becoming a common standard in this branch of manufacturing. Such trends cause either the use of advanced computational models that take into account the full 3D geometry of the flat and wavy layers of corrugated board, or the use of homogenization techniques to simplify the numerical model. The article presents theoretical considerations that extend the numerical homogenization technique already presented in our previous work. The proposed here homogenization procedure also takes into account the creasing and/or perforation of corrugated board (i.e., processes that undoubtedly weaken the stiffness and strength of the corrugated board locally). However, it is not always easy to estimate how exactly these processes affect the bending or torsional stiffness. What is known for sure is that the degradation of stiffness depends, among other things, on the type of cut, its shape, the depth of creasing as well as their position or direction in relation to the corrugation direction. The method proposed here can be successfully applied to model smeared degradation in a finite element or to define degraded interface stiffnesses on a crease line or a perforation line.

12.
Materials (Basel) ; 14(12)2021 Jun 10.
Article in English | MEDLINE | ID: mdl-34200842

ABSTRACT

The article presents the results of research on the structural evolution of the composite Fe-Al-based coating deposited by arc spray with initial low participation of in situ intermetallic phases. The arc spraying process was carried out by simultaneously melting two different electrode wires, aluminum and low alloy steel (98.6 wt.% of Fe). The aim of the research was to reach protective coatings with a composite structure consisting of a significant participation of FexAly as intermetallic phases reinforcement. Initially, synthesis of intermetallic phases took place in situ during the spraying process. In the next step, participation of FexAly fraction was increased through the annealing process, with three temperature values, 700 °C, 800 °C, and 900 °C. Phase structure evolution of the Fe-Al arc-sprayed coating, stimulated by annealing, has been described by means of SEM images taken with a QBSD backscattered electron detector and by XRD and conversion electron Mössbauer spectroscopy (CEMS) investigations. Microhardness distribution of the investigated annealed coatings has been presented.

13.
Am J Med Genet A ; 158A(6): 1442-6, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22581569

ABSTRACT

We present a boy diagnosed with partial 3p monosomy and partial 4q trisomy. The patient was 9 years of age with intellectual disability, dysmorphic features, and ataxia. A family history and medical evaluation showed that the father manifested similar facial dysmorphic features, intellectual disability, quadriparesis, and progressive cerebrospinal ataxia. The chromosomal aberration found in the proband was inherited from his father who was found to have a balanced reciprocal translocation of chromosomes 3p and 4q, which was in turn inherited from the paternal grandfather. The final cytogenetic diagnosis according to microarray was 46,XY,der(3)t(3;4)(p26.1;q32.2)arr 3p26.1(39,066-5,363,502)x1,4q32.2q35.2(162,555,236-191,173,881)x3. We describe the cytogenetic investigations that led to the identification of the breakpoints. In addition, we present an overview of the clinical features found in patients with partial 3p monosomies and partial 4q trisomies as reported in the literature.


Subject(s)
Abnormalities, Multiple/genetics , Ataxia/genetics , Chromosome Deletion , Intellectual Disability/genetics , Trisomy , Abnormalities, Multiple/diagnosis , Ataxia/diagnosis , Child , Child, Preschool , Chromosomes, Human, Pair 3 , Chromosomes, Human, Pair 4 , Comparative Genomic Hybridization , Humans , Intellectual Disability/diagnosis , Karyotyping , Male , Pedigree
14.
Kardiol Pol ; 70(4): 421-3, 2012.
Article in Polish | MEDLINE | ID: mdl-22528724

ABSTRACT

Systemic lupus erythematosus (SLE) is an autoimmune disorder resulting in multiorgan inflammatory damage. The heart is frequently involved in SLE. The best known cardiac manifestations are pericarditis and Libman-Saks endocarditis. Severe valvular impairment is rather rare and occurs in few years and in advanced stage of the disease. In this study we report a case of a young women with SLE and heart failure due to mitral regurgitation as the first manifestation of the disease.


Subject(s)
Heart Failure/etiology , Lupus Erythematosus, Systemic/complications , Mitral Valve Insufficiency/etiology , Mitral Valve/surgery , Echocardiography, Doppler, Color/methods , Female , Heart Failure/surgery , Heart Valve Prosthesis Implantation/methods , Humans , Mitral Valve Insufficiency/surgery , Time Factors , Young Adult
15.
Neurol Neurochir Pol ; 45(4): 391-8, 2011.
Article in Polish | MEDLINE | ID: mdl-22102001

ABSTRACT

The FMR1 gene premutation has recently been reported to be associated with a neurodegenerative syndrome, characterized by intention tremor, gait ataxia and cognition deficits in persons older than 50 years. We present a 74-year-old man with very severe intention tremor, slight postural tremor and gait ataxia. The molecular analysis revealed that he was a carrier of 91 CGG repeats in the FMR1 gene. His sister (68 years old), with head tremor, was found to be a carrier of 81 CGG repeats, while his younger brother, also with slight head and postural tremor, was a carrier of 98 CGG repeats. Molecular analysis of the proband's asymptomatic daughter revealed an expansion over 120 CGG. Her daughter, with mild intellectual disability, was a carrier of a full mutation. Thus, in the presented family with heterogeneous clinical presentation we found 4 premutations and one full mutation in the FMR1 gene.


Subject(s)
Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Mutation/genetics , Pedigree , Aged , Ataxia/genetics , Genetic Predisposition to Disease/genetics , Humans , Male , Phenotype , Tremor/genetics
16.
Neurol Neurochir Pol ; 44(3): 238-45, 2010.
Article in English | MEDLINE | ID: mdl-20625959

ABSTRACT

BACKGROUND AND PURPOSE: Autosomal dominant spinocerebellar ataxias (SCAs) belong to a group of neurodegenerative disorders usually of adult age at onset. Predominant clinical features are progressive ataxia, dysarthria, as well as pyramidal signs and polyneuropathy. Molecular analysis allows particular types of SCA to be distinguished. Genetic tests are applied in 10 types of SCA resulting from dynamic mutations: SCA1, SCA2, SCA3, SCA6, SCA7, SCA8, SCA10, SCA12, SCA17 and DRPLA. MATERIAL AND METHODS: DNA samples from 1598 patients with ataxia symptoms were analysed to establish the number of CAG/CTG repeats in respective genes excluding SCA10. RESULTS: We diagnosed 224 cases of SCA1 (120 families) and 49 cases of SCA2 (23 families). Moreover, presymptomatic testing was done in 85 individuals from SCA1 families and for 21 cases from SCA2 families. An increased number of CTG repeats in the SCA8 gene was observed in 14 families and in 3 families a rare type of SCA, SCA17, was detected. CONCLUSIONS: Our data suggest that frequencies of some types of SCA in Poland are different from those in other European countries, with irregular distribution within the country. The most frequent types are SCA1 and SCA2. A striking feature of the Polish population is the lack of SCA3 - the most frequent type in Western Europe.


Subject(s)
Gene Frequency , Mutation , Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , Repressor Proteins/genetics , Spinocerebellar Ataxias/genetics , Adult , Age of Onset , Aged , Alleles , Ataxin-1 , Ataxin-10 , Ataxin-3 , Ataxin-7 , Ataxins , Calcium Channels/genetics , DNA Mutational Analysis , Female , Genetics, Population , Humans , Male , Middle Aged , Poland/epidemiology , Protein Phosphatase 2/genetics , RNA, Long Noncoding , RNA, Untranslated , Spectrin/genetics , Spinocerebellar Ataxias/epidemiology , TATA-Box Binding Protein/genetics
17.
Neurol Neurochir Pol ; 44(3): 264-76, 2010.
Article in Polish | MEDLINE | ID: mdl-20625963

ABSTRACT

Myotonic dystrophy (DM), the most common dystrophy in adults, is an autosomal dominant disease characterized by a variety of multisystemic features. Two genetically distinct forms of DM are identified - type 1 (DM1), the classic form first described by Steinert, and type 2 (DM2), identified by Ricker. DM1 is caused by trinucleotide expansion of CTG in the myotonic dystrophy protein kinase gene, whereas in DM2 the expansion of tetranucleotide repeats (CCTG) in the zinc finger protein 9 gene was identified. Both mutations are dynamic and are located in non-coding parts of the genes. Phenotype variability of DM1 and DM2 is caused by a molecular mechanism due to mutated RNA toxicity. This paper reviews the clinical features of both types of myotonic dystrophies and summarizes current views on pathogenesis of myotonic dystrophy.


Subject(s)
Myotonic Dystrophy/diagnosis , Myotonic Dystrophy/genetics , Protein Serine-Threonine Kinases/genetics , RNA-Binding Proteins/genetics , Adult , Humans , Mutation , Myotonic Dystrophy/therapy , Myotonin-Protein Kinase , Phenotype
19.
Genet Test Mol Biomarkers ; 13(5): 651-5, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19715468

ABSTRACT

Molecular genetic testing of myotonic dystrophy type 1 (DM1) is based on the identification and determination of a cytosine-thymine-guanine (CTG) repeat expansion in the DMPK gene. This is usually done by Southern blot analysis-a time-consuming and very laborious technique requiring high molecular weight DNA. The aim of our study was to develop a highly sensitive, rapid, and cost-effective molecular analysis characterizing the CTG repeat region of the DMPK gene based on a two-step polymerase chain reaction (PCR) protocol. (1) For the detection of alleles of up to 100 repeats, a quantitative fluorescent (QF) amplification with primers flanking the repeat region of the DM1 locus and two reference genes (PAX2 and DHCR7) for standardization was used. By this method it was possible to identify both homozygous and heterozygous DM1 alleles. (2) Long PCR was only performed if a single wild-type allele was detected that gave a QF-PCR signal of only half intensity compared to a homozygous sample. The results obtained using combined QF and Long PCR are highly accurate compared with Southern blot analysis. We conclude that our new rapid analysis is reliable for genetic testing of DM1 patients.


Subject(s)
Myotonic Dystrophy/genetics , Polymerase Chain Reaction/methods , Base Sequence , Blotting, Southern , DNA Primers , Fluorescence , Heterozygote , Homozygote , Humans , Myotonic Dystrophy/diagnosis
20.
Cardiol J ; 15(5): 441-5, 2008.
Article in English | MEDLINE | ID: mdl-18810719

ABSTRACT

BACKGROUND: Heart rate turbulence (HRT) assessment is used as noninvasive method based on physiological sinus node response to the premature ventricular beat. Blunted HRT may indicate the autonomic nervous system impairment and can be helpful in identifying high-risk patients. Obstructive sleep apnea syndrome (OSAS) leads to cardiovascular complications. Autonomic nervous system and baroreflex dysfunctions may play the main role in the development of cardiovascular diseases. In the present study we aimed to assess HRT parameters in OSAS patients with and without coronary artery disease (CAD) in comparison to control group. METHODS: HRT analysis (TO--turbulence onset and TS--turbulence slope) was performed in 22 OSAS patients (confirmed by polisomnography, apnea-hypopnea index >or= 15) and 21 healthy persons, obtained from 24-hour ECG recordings. CAD was confirmed in 10 OSAS patients, by positive exercise test ECG and coronary angiography. RESULTS: TS was significantly lower in OSAS patients in comparison to control group (1.14 +/- +/- 2.83 vs. 21.28 +/- 16.2, p < 0.001). TO didn't differ in both group. Significant negative correlation between TS and apnea-hypopnea index was observed (r = 0.49, p < 0.01). There were no significant HRT changes in OSAS and CAD patients vs. OSAS without CAD patients, although tendency to more impaired HRT in OSAS and CAD patients was observed. CONCLUSIONS: In OSAS patients, blunted HRT (especially TS) was observed. This may indicate baro-reflex dysfunction correlated with the severity of sleep disorders. The additional diagnosis of CAD did not significantly influence HRT parameters.


Subject(s)
Autonomic Nervous System Diseases/complications , Coronary Artery Disease/complications , Heart Rate , Sleep Apnea, Obstructive/complications , Ventricular Premature Complexes/etiology , Adult , Aged , Autonomic Nervous System Diseases/physiopathology , Baroreflex/physiology , Coronary Artery Disease/physiopathology , Electrocardiography, Ambulatory , Female , Humans , Male , Middle Aged , Polysomnography , Sinoatrial Node/physiopathology , Ventricular Premature Complexes/diagnosis , Ventricular Premature Complexes/physiopathology
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