A Literature Review on the Development and Creation of Digital Twins, Cyber-Physical Systems, and Product-Service Systems

Digital Twins offer vast potential, yet many companies, particularly small and medium-sized enterprises, hesitate to implement them. This hesitation stems partly from the challenges posed by the interdisciplinary nature of creating Digital Twins. To address these challenges, this paper explores systematic approaches for the development and creation of Digital Twins, drawing on relevant methods and approaches presented in the literature. Conducting a systematic literature review, we delve into the development of Digital Twins while also considering analogous concepts, such as Cyber-Physical Systems and Product-Service Systems. The compiled literature is categorised into three main sections: holistic approaches, architecture, and models. Each category encompasses various subcategories, all of which are detailed in this paper. Through this comprehensive review, we discuss the findings and identify research gaps, shedding light on the current state of knowledge in the field of Digital Twin development. This paper aims to provide valuable insights for practitioners and researchers alike, guiding them in navigating the complexities associated with the implementation of Digital Twins.

Automatic Neurocranial Landmarks Detection from Visible Facial Landmarks Leveraging 3D Head Priors

The localization and tracking of neurocranial landmarks is essential in modern medical procedures, e.g., transcranial magnetic stimulation (TMS). However, state-of-the-art treatments still rely on the manual identification of head targets and require setting retroreflective markers for tracking. This limits the applicability and scalability of TMS approaches, making them time-consuming, dependent on expensive hardware, and prone to errors when retroreflective markers drift from their initial position. To overcome these limitations, we propose a scalable method capable of inferring the position of points of interest on the scalp, e.g., the International 10-20 System's neurocranial landmarks. In contrast with existing approaches, our method does not require human intervention or markers; head landmarks are estimated leveraging visible facial landmarks, optional head size measurements, and statistical head model priors. We validate the proposed approach on ground truth data from 1,150 subjects, for which facial 3D and head information is available; our technique achieves a localization RMSE of 2.56 mm on average, which is of the same order as reported by high-end techniques in TMS. Our implementation is available at https://github.com/odedsc/ANLD.

Systematic assessment of long-read RNA-seq methods for transcript identification and quantification

The Long-read RNA-Seq Genome Annotation Assessment Project (LRGASP) Consortium was formed to evaluate the effectiveness of long-read approaches for transcriptome analysis. The consortium generated over 427 million long-read sequences from cDNA and direct RNA datasets, encompassing human, mouse, and manatee species, using different protocols and sequencing platforms. These data were utilized by developers to address challenges in transcript isoform detection and quantification, as well as de novo transcript isoform identification. The study revealed that libraries with longer, more accurate sequences produce more accurate transcripts than those with increased read depth, whereas greater read depth improved quantification accuracy. In well-annotated genomes, tools based on reference sequences demonstrated the best performance. When aiming to detect rare and novel transcripts or when using reference-free approaches, incorporating additional orthogonal data and replicate samples are advised. This collaborative study offers a benchmark for current practices and provides direction for future method development in transcriptome analysis.

Characterizing the short-latency evoked response to intracortical microstimulation across a multi-electrode array

OBJECTIVE

Persons with tetraplegia can use brain-machine interfaces to make visually guided reaches with robotic arms. Without somatosensory feedback, these movements will likely be slow and imprecise, like those of persons who retain movement but have lost proprioception. Intracortical microstimulation (ICMS) has promise for providing artificial somatosensory feedback. If ICMS can mimic naturally occurring neural activity, afferent interfaces may be more informative and easier to learn than interfaces that evoke unnaturalistic activity. To develop such biomimetic stimulation patterns, it is important to characterize the responses of neurons to ICMS.

APPROACH

Using a Utah multi-electrode array, we recorded activity evoked by single pulses and trains of ICMS at a wide range of amplitudes and frequencies in two rhesus macaques. As the electrical artifact caused by ICMS typically prevents recording for many milliseconds, we deployed a custom rapid-recovery amplifier with nonlinear gain to limit signal saturation on the stimulated electrode. Across all electrodes after stimulation, we removed the remaining slow return to baseline with acausal high-pass filtering of time-reversed recordings.

MAIN RESULTS

After single pulses of stimulation, we recorded what was likely transsynaptically-evoked activity even on the stimulated electrode as early as ~0.7 ms. This was immediately followed by suppressed neural activity lasting 10-150 ms. After trains, this long-lasting inhibition was replaced by increased firing rates for ~100 ms. During long trains, the evoked response on the stimulated electrode decayed rapidly while the response was maintained on non-stimulated channels.

SIGNIFICANCE

The detailed description of the spatial and temporal response to ICMS can be used to better interpret results from experiments that probe circuit connectivity or function of cortical areas. These results can also contribute to the design of stimulation patterns to improve afferent interfaces for artificial sensory feedback.

Multichannel power electronics and magnetic nanoparticles for selective thermal magnetogenetics

OBJECTIVE

We present a combination of a power electronics system and magnetic nanoparticles that enable frequency-multiplexed magnetothermal-neurostimulation with rapid channel switching between three independent channels spanning a wide frequency range.

APPROACH

The electronics system generates alternating magnetic field spanning 50 kHz to 5 MHz in the same coil by combining silicon (Si) and gallium-nitride (GaN) transistors to resolve the high spread of coil impedance and current required throughout the wide bandwidth. The system drives a liquid-cooled field coil via capacitor banks, forming three series resonance channels which are multiplexed using high-voltage contactors. We characterized the system by the output channels' frequencies, field strength, and switching time, as well as the system's overall operation stability. Using different frequency-amplitude combinations of the magnetic field to target specific magnetic nanoparticles with different coercivity, we demonstrate actuation of iron oxide nanoparticles in all three channels, including a novel nanoparticle composition responding to magnetic fields in the megahertz range.

MAIN RESULTS

The system achieved the desired target field strengths for three frequency channels, with switching speed between channels on the order of milliseconds. Specific absorption rate measurements and infrared thermal imaging performed with three types of magnetic nanoparticles demonstrated selective heating and validated the system's intended use.

SIGNIFICANCE

The system uses a hybrid of Si and GaN transistors in bridge configuration instead of conventional amplifier circuit concepts to drive the magnetic field coil and contactors for fast switching between different capacitor banks. Series-resonance circuits ensure a high output quality while keeping the system efficient. This approach could significantly improve the speed and flexibility of frequency-multiplexed nanoparticle actuation, such as magnetogenetic neurostimulation, and thus provide the technical means for selective stimulation below the magnetic field's fundamental spatial focality limits.

Prediction of Force Recruitment of Neuromuscular Magnetic Stimulation From 3D Field Model of the Thigh

Neuromuscular magnetic stimulation is a promising tool in neurorehabilitation due to its deeper penetration, notably lower distress, and respectable force levels compared to surface electrical stimulation. However, this method faces great challenges from a technological perspective. The systematic design of better equipment and the incorporation into modern training setups requires better understanding of the mechanisms and predictive quantitative models of the recruited forces. This article proposes a model for simulating the force recruitment in isometric muscle stimulation of the thigh extensors based on previous theoretical and experimental findings. The model couples a 3D field model for the physics with a parametric recruitment model. This parametric recruitment model is identified with a mixed-effects design to learn the most likely model based on available experimental data with a wide range of field conditions. This approach intentionally keeps the model as mathematically simple and statistically parsimonious as possible in order to avoid over-fitting. The work demonstrates that the force recruitment particularly depends on the effective, i.e., fiber-related cross section of the muscles, and that the local median electric field threshold amounts to about 65 V/m, which agrees well with values for magnetic stimulation in the brain. The coupled model is able to accurately predict key phenomena observed so far, such as a threshold shift for different distances between coil and body, the different recruiting performance of various coils with available measurement data in the literature, and the saturation behavior with its onset amplitude. The presented recruitment model could also be readily incorporated into dynamic models for biomechanics as soon as sufficient experimental data are available for calibration.

Does the identification of seniors at risk (ISAR) score effectively select geriatric patients on emergency admission?

The number of older patients admitted to emergency departments (ED) increases continuously. The Identification of Seniors at Risk (ISAR) score is currently recommended to screen patients in German ED, but its appropriateness is being criticized. ISAR scores and clinical characteristics from 98 emergency admissions (EA), 80 from acute geriatrics (AG) and 89 from a geriatric rehabilitation (GR) unit were compared retrospectively. No significant differences were found between groups, being the ISAR score positive in 87.7% of EA, 94.9% of AG and 94.4% of GR cases. None of positively identified geriatric patients in the EA was transferred to the geriatric ward of competence. EA patients showed significantly higher number of functional impairments (p = 0.001) and higher BI score (p < 0.0001) compared to AG and GR groups. A higher ISAR score threshold and additional functional information might be needed to better select patients in need of prompt treatment by a geriatric team.

Preliminary evidence that testosterone's association with aggression depends on self-construal

A contribution to a special issue on Hormones and Human Competition. Previous research and theory suggest testosterone is an important hormone for modulating aggression and self-regulation. We propose that self-construal, a culturally-relevant difference in how individuals define the self in relation to others, may be an important moderator of the relationship between testosterone and behaviors linked to aggression. Within two studies (Study 1 N=80; Study 2 N=237) and an integrated data analysis, we find evidence suggesting that acute testosterone changes in men are positively associated with aggressive behavior for those with more independent self-construals, whereas basal testosterone is negatively associated with aggression when individuals have more interdependent self-construals. Although preliminary, these findings suggest that self-construal moderates the association between testosterone and aggression, thereby paving the way toward future work examining the potential cultural moderation of the behavioral effects of testosterone.

A preliminary experimental examination of worldview verification, perceived racism, and stress reactivity in African Americans

OBJECTIVE

According to worldview verification theory, inconsistencies between lived experiences and worldviews are psychologically threatening. These inconsistencies may be key determinants of stress processes that influence cardiovascular health disparities. This preliminary examination considers how experiencing injustice can affect perceived racism and biological stress reactivity among African Americans. Guided by worldview verification theory, it was hypothesized that responses to receiving an unfair outcome would be moderated by fairness of the accompanying decision process, and that this effect would further depend on the consistency of the decision process with preexisting justice beliefs.

METHOD

A sample of 118 healthy African American adults completed baseline measures of justice beliefs, followed by a laboratory-based social-evaluative stressor task. Two randomized fairness manipulations were implemented during the task: participants were given either high or low levels of distributive (outcome) and procedural (decision process) justice. Glucocorticoid (cortisol) and inflammatory (C-reactive protein) biological responses were measured in oral fluids, and attributions of racism were also measured.

RESULTS

The hypothesized 3-way interaction was generally obtained. Among African Americans with a strong belief in justice, perceived racism, cortisol, and C-reactive protein responses to low distributive justice were higher when procedural justice was low. Among African Americans with a weak belief in justice however, these responses were higher when a low level of distributive justice was coupled with high procedural justice.

CONCLUSIONS

Biological and psychological processes that contribute to cardiovascular health disparities are affected by consistency between individual-level and contextual justice factors. (PsycINFO Database Record

Coordination of cortisol response to social evaluative threat with autonomic and inflammatory responses is moderated by stress appraisals and affect

Recent approaches to stress regulation have emphasized coordination among multiple biological systems. This study builds on evidence that hypothalamic-pituitary-adrenal (HPA) axis activity should be considered in coordination with other stress-sensitive biological systems to characterize healthy responses. Healthy African-Americans (n=115) completed the Trier Social Stress Test, and biological responses were assessed through salivary cortisol, dehydroepiandrosterone-sulfate (DHEA-S), alpha amylase (sAA), and C-reactive protein (sCRP). Multilevel modeling demonstrated that cortisol responses typically aligned with changes in DHEA-S, sAA, and sCRP across the session. At the same time, the degree of cortisol coordination with sAA and sCRP varied by participants' subjective stress following the task; participants with higher secondary stress appraisals showed greater cortisol-sAA alignment, whereas those experiencing more negative affect showed greater cortisol-sCRP alignment. Results highlight the importance of a multisystem approach to stress and suggest that positive HPA axis coordination with the autonomic response, but not with the immune/inflammatory response, may be adaptive.

Muscle force development after low-frequency magnetic burst stimulation in dogs

INTRODUCTION

Magnetic stimulation allows for painless and non-invasive extrinsic motor nerve stimulation. Despite several advantages, the limited coupling to the target reduces the application of magnetic pulses in rehabilitation. According to experience with electrical stimulation, magnetic bursts could remove this constraint.

METHODS

A novel burst stimulator was used to apply single and burst pulses to the femoral nerve in 10 adult dogs. A figure-of-eight coil was connected, and pulses were applied at 7.5 HZ. Contractions of the quadriceps muscle were measured via an angle force transducer.

RESULTS

Muscle forces were significantly higher upon burst stimulation than after single pulses. Four consecutive burst pulses proved most effective. Stimulation by more bursts resulted in fatigue.

CONCLUSION

Burst stimulation is superior to standard magnetic single pulses, and 4 consecutive burst pulses proved most effective.

Babelomics: an integrative platform for the analysis of transcriptomics, proteomics and genomic data with advanced functional profiling

Babelomics is a response to the growing necessity of integrating and analyzing different types of genomic data in an environment that allows an easy functional interpretation of the results. Babelomics includes a complete suite of methods for the analysis of gene expression data that include normalization (covering most commercial platforms), pre-processing, differential gene expression (case-controls, multiclass, survival or continuous values), predictors, clustering; large-scale genotyping assays (case controls and TDTs, and allows population stratification analysis and correction). All these genomic data analysis facilities are integrated and connected to multiple options for the functional interpretation of the experiments. Different methods of functional enrichment or gene set enrichment can be used to understand the functional basis of the experiment analyzed. Many sources of biological information, which include functional (GO, KEGG, Biocarta, Reactome, etc.), regulatory (Transfac, Jaspar, ORegAnno, miRNAs, etc.), text-mining or protein–protein interaction modules can be used for this purpose. Finally a tool for the de novo functional annotation of sequences has been included in the system. This provides support for the functional analysis of non-model species. Mirrors of Babelomics or command line execution of their individual components are now possible. Babelomics is available at http://www.babelomics.org.

Babelomics: advanced functional profiling of transcriptomics, proteomics and genomics experiments

We present a new version of Babelomics, a complete suite of web tools for the functional profiling of genome scale experiments, with new and improved methods as well as more types of functional definitions. Babelomics includes different flavours of conventional functional enrichment methods as well as more advanced gene set analysis methods that makes it a unique tool among the similar resources available. In addition to the well-known functional definitions (GO, KEGG), Babelomics includes new ones such as Biocarta pathways or text mining-derived functional terms. Regulatory modules implemented include transcriptional control (Transfac, CisRed) and other levels of regulation such as miRNA-mediated interference. Moreover, Babelomics allows for sub-selection of terms in order to test more focused hypothesis. Also gene annotation correspondence tables can be imported, which allows testing with user-defined functional modules. Finally, a tool for the ‘de novo’ functional annotation of sequences has been included in the system. This allows using yet unannotated organisms in the program. Babelomics has been extensively re-engineered and now it includes the use of web services and Web 2.0 technology features, a new user interface with persistent sessions and a new extended database of gene identifiers. Babelomics is available at http://www.babelomics.org

GEPAS, a web-based tool for microarray data analysis and interpretation

Gene Expression Profile Analysis Suite (GEPAS) is one of the most complete and extensively used web-based packages for microarray data analysis. During its more than 5 years of activity it has continuously been updated to keep pace with the state-of-the-art in the changing microarray data analysis arena. GEPAS offers diverse analysis options that include well established as well as novel algorithms for normalization, gene selection, class prediction, clustering and functional profiling of the experiment. New options for time-course (or dose-response) experiments, microarray-based class prediction, new clustering methods and new tests for differential expression have been included. The new pipeliner module allows automating the execution of sequential analysis steps by means of a simple but powerful graphic interface. An extensive re-engineering of GEPAS has been carried out which includes the use of web services and Web 2.0 technology features, a new user interface with persistent sessions and a new extended database of gene identifiers. GEPAS is nowadays the most quoted web tool in its field and it is extensively used by researchers of many countries and its records indicate an average usage rate of 500 experiments per day. GEPAS, is available at http://www.gepas.org.

Intermediate results of health related quality of life after vertical banded gastroplasty

OBJECTIVES

The purpose of this study is to evaluate (a) health-related quality of life (HRQL) after vertical banded gastroplasty (VBG) (Mason) and (b) predictors of HRQL.

SUBJECTS

Eighty-two consecutive patients were assessed preoperatively and then after 6, 12 and 24 months. Patients filled out questionnaires for subjective appraisal of HRQL (physical well-being, mood, physical performance, perceived health, social support and coping/adjustment).

RESULTS

The greatest improvement in weight and HRQL was seen within 6 months of surgery. Twenty-four months after VBG weight reduction (P<0.05), perceived health (P<0.05), physical well-being (P<0.05), physical performance (P<0.05), mood (P<0.05), coping/adjustment (P<0.05) continued to be better than before surgery. Preoperative binge eating was the most important predictor of HRQL.

CONCLUSION

Two years after VBG weight loss and a significant improvement of HRQL can be found. HRQL and weight loss are not associated in terms of outcome, indicating that weight loss alone may not be enough to improve HRQL.

Discoidin domain receptor 1 (DDR1) signaling in PC12 cells: activation of juxtamembrane domains in PDGFR/DDR/TrkA chimeric receptors

The discoidin domain receptor (DDR1) is characterized by a discoidin I motif in the extracellular domain, an unusually long cytoplasmic juxtamembrane (JM) region, and a kinase domain that is 45% identical to that of the NGF receptor, TrkA. DDR1 also has a major splice form, which has a 37 amino acid insert in the JM region with a consensus Shc PTB site that is lacking in the shorter receptor. One class of ligands for the DDR receptors has recently been identified as being derived from the collagen family, but neither native PC12 cells, which express modest amounts of DDR1, nor transfected PC12 cells, which express much larger amounts of DDR1, respond to this ligand. A chimeric receptor, containing the extracellular domain of hPDGFRbeta fused to the transmembrane and intracellular regions of DDR1, also fails to mediate neuronal-like differentiation in stably transfected PC12 cells and is only weakly autophosphorylated. However, chimeric receptors, which are composed of combinations of intracellular regions from DDR1 and TrkA (with the extracellular domain of hPDGFRbeta), in some cases provided ligand (PDGF) -inducible receptor responses. Those with the TrkA kinase domain and the DDR1 JM regions were able to produce differentiation to varying degrees, whereas the opposite combination did not. Analysis of the signaling responses of the two chimeras with DDR1 JM sequences (with and without the insert) indicated that the shorter sequence bound and activated FRS2 whereas the insert-containing form activated Shc instead. Both activated PLCgamma through the carboxyl-terminal tyrosine of the TrkA domain (Y785 in TrkA residue numbering). Mutation of this site (Y-->F) eliminated PLCgamma activation (indicating there are no other cryptic binding sites for PLCgamma in the DDR1 sequences) and markedly reduced the differentiative activity of the receptor. This is in contrast to TrkA (or PDGFRbeta/TrkA chimeras), where ablation of this pathway has no notable effect on PC12 cell morphogenic responses. Thus, the activation of FRS2 and Shc (leading to MAPK activation) is weaker in the DDR1/TrkA chimeras than in TrkA alone, and the PLCgamma contribution becomes essential for full response. Nonetheless, both DDR1 JM regions contain potentially usable signaling sites, albeit they apparently are not activated directly in DDR1 (or DDR1 chimeras) in a ligand-dependent fashion. These findings suggest that the DDR1 receptors do have signaling capacity but may require additional components or altered conditions to fully activate their kinase domains and/or sustain the activation of the JM sites.

Forensic issues in the psychiatric emergency department

To function effectively in the ED, mental health clinicians must be able to: Competently evaluate and manage psychiatric patients in acute crisis. Obtain informed consent for treatment or procedures from patients or substitute health care decision makers. Develop clinical data about patients from collateral sources, such as family members and current treaters. Retrieve records of previous admissions to the ED or hospital psychiatric unit. Conduct competent suicide and violence risk assessments that direct clinical interventions. Conduct risk-benefit assessments before discharging suicidal or potentially violent patients. Observe basic safety precautions and procedures with potentially violent patients. Work with community mental health facilities for the follow-up care of chronically mentally ill patients. Possess a working knowledge of the legal regulation of mental health practice, especially as it applies to evaluating and treating patients in the ED. Obtain legal consultation when in doubt about matters of law affecting patient care.

[Struma, hyper- and hypothyroidism]

Careful history and physical examination form the basis of thyroid diagnostics. They are important for the choice of the appropriate laboratory and imaging tests such as sonography and scintigraphy. Estimation of FT4 and TSH (measured with a 'sensitive' assay) are nowadays considered to be the principal laboratory tests for thyroid disease. Euthyroidism and hypothyroidism are confirmed by measuring FT4 and TSH (not FT3 or TT3), hyperthyroidism by measuring FT3, FT4 and TSH. If a goitre is observed, the primary tests are TSH and sonography.

High "need for control" as a psychological risk in women suffering from ischemic stroke: a controlled retrospective exploratory study

The assumption is tested that women scoring high on dimensions of coping pattern termed "need for control," which underlies several of the components of Type A behavior, are at increased risk of ischemic cerebrovascular disease. Consecutively admitted patients to medical wards, nineteen with ischemic cerebrovascular disease, were compared with nineteen patients with non-arteriovascular disease and nineteen healthy females doing volunteer hospital work. "Need for control" was assessed by a psychometric test based on forty-five dichotomous items defining six unidimensional scales. The Bortner Type A behavior was filled out by the subjects and by their next of kin for an impression of the subject. In ANOVA the dimensions "work commitment, hard driving" (F = 6.87, p less than .002), "perfectionism, need for making plans" (F = 6.26, p less than .003), and "inability to withdraw from work obligations" (F = 3.89, p less than .02) differentiated the three groups in the expected direction. Duncan multiple range test resulted in very similar, significant findings, as did Bortner measures, filled out by a next of kin (F = 4.63, p less than .01). In all analyses, effects of age, current smoking, and coronary artery disease (CAD) were controlled. Our results suggest that high "need for control" defines a psychological risk in women suffering from ischemic stroke. Prospective studies should be undertaken. If they confirm our results, interventions aimed at modifying the "need for control" should be planned.