Additive manufacturing (AM) or 3D printing is growing rapidly in the manufacturing industry and has gained a lot of attention from various fields owing to its ability to fabricate parts with complex ...features. The reliability of the 3D printed parts has been the focus of the researchers to realize AM as an end-part production tool. Machine learning (ML) has been applied in various aspects of AM to improve the whole design and manufacturing workflow especially in the era of industry 4.0. In this review article, various types of ML techniques are first introduced. It is then followed by the discussion on their use in various aspects of AM such as design for 3D printing, material tuning, process optimization, in situ monitoring, cloud service, and cybersecurity. Potential applications in the biomedical, tissue engineering and building and construction will be highlighted. The challenges faced by ML in AM such as computational cost, standards for qualification and data acquisition techniques will also be discussed. In the authors’ perspective, in situ monitoring of AM processes will significantly benefit from the object detection ability of ML. As a large data set is crucial for ML, data sharing of AM would enable faster adoption of ML in AM. Standards for the shared data are needed to facilitate easy sharing of data. The use of ML in AM will become more mature and widely adopted as better data acquisition techniques and more powerful computer chips for ML are developed.
Aims/hypothesis Insulin resistance (IR) is associated with obesity, but can also develop in individuals with normal body weight. We employed comprehensive profiling methods to identify metabolic ...events associated with IR, while controlling for obesity. Methods We selected 263 non-obese (BMI approximately 24 kg/m²) Asian-Indian and Chinese men from a large cross-sectional study carried out in Singapore. Individuals taking medication for diabetes or hyperlipidaemia were excluded. Participants were separated into lower and upper tertiles of IR based on HOMA indices of ≤1.06 or ≥1.93, respectively. MS-based metabolic profiling of acylcarnitines, amino acids and organic acids was combined with hormonal and cytokine profiling in all participants. Results After controlling for BMI, commonly accepted risk factors for IR, including circulating fatty acids and inflammatory cytokines, did not discriminate the upper and lower quartiles of insulin sensitivity in either Asian-Indian or Chinese men. Instead, IR was correlated with increased levels of alanine, proline, valine, leucine/isoleucine, phenylalanine, tyrosine, glutamate/glutamine and ornithine, and a cluster of branched-chain and related amino acids identified by principal components analysis. These changes were not due to increased protein intake by individuals in the upper quartile of IR. Increased abdominal adiposity and leptin, and decreased adiponectin and IGF-binding protein 1 were also correlated with IR. Conclusions/interpretation These findings demonstrate that perturbations in amino acid homeostasis, but not inflammatory markers or NEFAs, are associated with IR in individuals of relatively low body mass.
Summary
Background Null mutations in the filaggrin gene (FLG) cause ichthyosis vulgaris (IV) and predispose to atopic dermatitis (AD). Cohort studies in Europe and Japan have reported an FLG ...mutation carrier frequency of between 14% and 56%, but the prevalent European FLG mutations are rare or absent in Chinese patients with IV and AD.
Objectives To investigate further the spectrum of FLG‐null mutations in Chinese patients and to compare it with that in other populations.
Methods We conducted comprehensive FLG genetic analysis in a discovery cohort of 92 Singaporean Chinese individuals with IV and/or moderate‐to‐severe AD. All detected FLG mutations were then screened in a cohort of 425 patients with AD and 440 normal controls.
Results In total, 22 FLG‐null mutations, of which 14 are novel, were identified in this study; the combined null FLG genotype of 17 mutations detected in cases and controls showed strong association with AD Fisher’s exact test; P = 5·3 × 10−9; odds ratio (OR) 3·3, palmar hyperlinearity (Fisher’s exact test; P = 9·0 × 10−15; OR 5·8), keratosis pilaris (Fisher’s exact test; P = 0·001; OR 4·7) and with increased severity of AD (permutation test; P = 0·0063).
Conclusions This study emphasizes the wider genetic landscape of FLG‐null mutations in Asia that is slowly emerging.
Photoreceptor replacement by transplantation is proposed as a treatment for blindness. Transplantation of healthy photoreceptor precursor cells into diseased murine eyes leads to the presence of ...functional photoreceptors within host retinae that express an array of donor-specific proteins. The resulting improvement in visual function was understood to be due to donor cells integrating within host retinae. Here, however, we show that while integration occurs the majority of donor-reporter-labelled cells in the host arises as a result of material transfer between donor and host photoreceptors. Material transfer does not involve permanent donor-host nuclear or cell-cell fusion, or the uptake of free protein or nucleic acid from the extracellular environment. Instead, RNA and/or protein are exchanged between donor and host cells in vivo. These data require a re-evaluation of the mechanisms underlying rescue by photoreceptor transplantation and raise the possibility of material transfer as a strategy for the treatment of retinal disorders.
Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric ...asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re‐evaluate and fine‐tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype‐specific treatment choices; however, this goal has not yet been achieved.
Auscultation based diagnosis of pulmonary disorders relies on the presence of adventitious sounds. In this paper, we propose a new set of features based on temporal characteristics of filtered ...narrowband signal to classify respiratory sounds (RSs) into normal and continuous adventitious types. RS signals are first decomposed in the time–frequency domain and features are extracted over selected frequency bins containing distinct signal characteristics based on auto-regressive averaging, the recursively measured instantaneous kurtosis, and the sample entropy histograms distortion. The presented features are compared with existing features using a modified clustering index with different distance metrics. Mean classification accuracies of 97.7% and 98.8% for inspiratory and expiratory segments respectively have been achieved using Support Vector Machine on real recordings.
While a number of tools have been developed for researchers to compute the lexical characteristics of words, extant resources are limited in their useability and functionality. Specifically, some ...tools require users to have some prior knowledge of some aspects of the applications, and not all tools allow users to specify their own corpora. Additionally, current tools are also limited in terms of the range of metrics that they can compute. To address these methodological gaps, this article introduces LexiCAL, a fast, simple, and intuitive calculator for lexical variables. Specifically, LexiCAL is a standalone executable that provides options for users to calculate a range of theoretically influential surface, orthographic, phonological, and phonographic metrics for any alphabetic language, using any user-specified input, corpus file, and phonetic system. LexiCAL also comes with a set of well-documented Python scripts for each metric, that can be reproduced and/or modified for other research purposes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background: Femoroacetabular impingement has become a well-recognized entity predisposing to acetabular labral tears and chondral damage, and subsequently development of osteoarthritis of the hip ...joint. In the authors’ experience, it is common to see bony abnormalities predisposing to femoroacetabular impingement in the contralateral asymptomatic hips in patients with unilateral femoroacetabular impingement.
Purpose: This study was undertaken to investigate the prevalence of bony abnormalities predisposing to femoroacetabular impingement in asymptomatic individuals without exposing study participants to unnecessary radiation.
Study Design: Cross-sectional study; Level of evidence, 4.
Methods: Fifty individuals (100 hip joints), ranging from 15 to 40 years of age, who were seen at a local hospital between March and August 2008 with abdominal trauma or nonspecific abdominal pain in whom abdominal computed tomography was performed to aid diagnosis were prospectively studied. These patients were not known to have any history of hip-related problems. Raw data from the abdominal computed tomography scan, performed on a 64-slice multidetector computed tomography scanner, were reformatted using bone algorithm into several different planes. Several measurements and observations of the hip joints were made in relation to femoroacetabular impingement.
Results: The 100 hip joints from 50 patients with no history of hip problems demonstrated that 39% of the joints (31% of female, 48% of male joints) have at least 1 morphologic aspect predisposing to femoroacetabular impingement. The majority (66% to 100% ) of the findings were bilateral; 33% of female and 52% of male asymptomatic participants in our study had at least 1 predisposing factor for femoroacetabular impingement in 1 or both of their hip joints. Based on the data collected from this study, the acetabular crossover sign had a 71% sensitivity and 88% specificity for detecting acetabular retroversion. Nonquantitative assessment of the femoral head at the anterior, anterolateral, and lateral head/neck junctions demonstrated that 74% of the joints had an aspherical femoral head.
Conclusion: The study demonstrated substantial prevalence of bony characteristics predisposing to femoroacetabular impingement in asymptomatic individuals according to the established measurement parameters in current literature.
This article provides a database of the mechanical properties of additively manufactured polymeric materials fabricated using material extrusion (e.g., fused filament fabrication (FFF)). Mechanical ...properties available in the literatures are consolidated in table form for different polymeric materials for FFF. Mechanical properties such as tensile, compressive, flexural, interlayer, fatigue, and creep properties are discussed in detail. The effects of printing parameters such as raster angle, infill, and specimen orientation on properties are also provided, together with a discussion of the possible causes (e.g., texture, microstructure changes, and defects) of anisotropy in properties. In addition to that, research gaps are identified which warrant further investigation.
While significant progress has been made in understanding laser powder bed fusion (L-PBF) as well as the fabrication of various materials using this technology, there is still limited adoption in the ...industry. One of the key obstacles identified is the lack of materials that can truly manufacture functional parts directly with L-PBF. This paper covers the emerging research on in-situ alloying and multi-metal processing. A comprehensive overview of the underlying scientific topics behind them is presented. The current state of research and progress from different perspectives (the materials and L-PBF processing parameters) are reviewed in order to provide a basis for follow-up research and development of these approaches. Defects, especially those associated with these two material processing routes, are also elucidated by discussing the mechanisms of their formation, including the main influencing factors, and the tendency for them to occur. Future research trends and potential topics are illustrated. The final part of this paper summarizes findings from this review and outlines the possibility of in-situ alloying and multi-metal processing using L-PBF.
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