sEMG-Based Robust Recognition of Grasping Postures with a Machine Learning Approach for Low-Cost Hand Control

The design and control of artificial hands remains a challenge in engineering. Popular prostheses are bio-mechanically simple with restricted manipulation capabilities, as advanced devices are pricy or abandoned due to their difficult communication with the hand. For social robots, the interpretation of human intention is key for their integration in daily life. This can be achieved with machine learning (ML) algorithms, which are barely used for grasping posture recognition. This work proposes an ML approach to recognize nine hand postures, representing 90% of the activities of daily living in real time using an sEMG human-robot interface (HRI). Data from 20 subjects wearing a Myo armband (8 sEMG signals) were gathered from the NinaPro DS5 and from experimental tests with the YCB Object Set, and they were used jointly in the development of a simple multi-layer perceptron in MATLAB, with a global percentage success of 73% using only two features. GPU-based implementations were run to select the best architecture, with generalization capabilities, robustness-versus-electrode shift, low memory expense, and real-time performance. This architecture enables the implementation of grasping posture recognition in low-cost devices, aimed at the development of affordable functional prostheses and HRI for social robots.

Distortions in time perception related to videogames, pornography, and TV series exposure: An experimental study in three independent samples

Background and aims

Time perception is a cognitive process involving both the ability to estimate the duration of an event (time estimation, TE) and the subjective perception of its passage (time passage, TP). Studies show that alteration in TE/TP is associated with substance use disorders. However, little is known about the impact of these alterations in potentially problematic online behaviors. We explore TE and TP while participants were exposed to cues related to videogames, pornography, and TV series, and the relationship of TE and TP with scores from instruments that measure problematic gaming (PG), problematic pornography use (PPU), and problematic binge-watching (BW).

Methods

Participants from three independent samples (40 men from Luxembourg; 99 Spanish men, 111 Spanish women) completed an experimental task designed to assess TE and TP while they were exposed to short clips related to videogames, pornography, TV series, and documentaries (control condition). Participants also completed different self-reports.

Results

Whereas men underestimated the time that they were exposed to pornography and TV series, women overestimated it. For videogames, we showed a consistent pattern of overestimation of time duration. Time was systematically perceived as passing faster while participants were presented with TV series and pornography. Regarding the association between time perception and PG, PPU, and BW, TE did not correlate with any of the indicators of problematic engagement assessed; but TP correlated with several of these indicators.

Discussion and conclusions

The present preliminary results showed mixed evidence regarding the involvement of time perception in gaming, pornography use, and binge-watching.

Coping with the Stress through Individual and Contextual Resilient Factors in Primary School Settings

Children face school stress as students through all educational stages. A negative association between resilience and stress has been demonstrated by many authors, but most of these studies have been carried out in higher educational stages. So, the aim of the present study is, on the one hand, to find out the level of stress of primary school children and also the types of stressful situations in school settings, and on the other hand, to analyze the effect of individual and contextually resilient factors on their level of school stress. The study involved 427 children between 6 and 12 years of age, who were administered the IECI school stress scale and the RES-PRIM Resilience questionnaire for children. Descriptive analyses, correlations, and regression analyses were performed on the data. Results showed an average level of school stress, with the most stressful situations being: participating in too many activities, concentration problems, and nervousness when being asked by the teacher in class. Predictive analysis showed that part of the school stress could be explained by both individual factors (self-esteem, introspection, future purpose, and social skills) and resilient contextual factors (teacher support, parental support, and peer support). It is concluded that it is necessary to pay more attention to the transitions between different educational stages with programs that reinforce academic information and encourage the development of individual resilient skills, stressing the importance of the role of teachers, peers, and parents as support groups.

Improving Nursing Assessment in Adult Hospitalization Units: A Secondary Analysis

The main objective of this study was to analyze the impact of a multifaceted strategy to improve the assessment of functional capacity, risk of pressure injuries, and risk of falls at the time of admission of patients in adult hospitalization units. This was a secondary analysis of the VALENF project databases during two periods (October-December 2020, before the strategy, and October-December 2021, after the strategy). The quantity and quality of nursing assessments performed on patients admitted to adult hospitalization units were evaluated using the Barthel index, Braden index, and Downton scale. The number of assessments completed before the implementation of the new strategy was n = 686 (28.01%), versus n = 1445 (58.73%) in 2021 (p < 0.001). The strategy improved the completion of the evaluations of the three instruments from 63.4% (n = 435) to 71.8% (n = 1038) (p < 0.001). There were significant differences depending on the hospitalization unit and the assessment instrument (p < 0.05). The strategy employed was, therefore, successful. The nursing assessments show a substantial improvement in both quantity and quality, representing a noticeable improvement in nursing practice. This study was not registered.

Foot Sole Contact Forces vs. Ground Contact Forces to Obtain Foot Joint Moments for In-Shoe Gait-A Preliminary Study

In-shoe models are required to extend the clinical application of current multisegment kinetic models of the bare foot to study the effect of foot orthoses. Work to date has only addressed marker placement for reliable kinematic analyses. The purpose of this study is to address the difficulties of recording contact forces with available sensors. Ten participants walked 5 times wearing two different types of footwear by stepping on a pressure platform (ground contact forces) while wearing in-shoe pressure sensors (foot sole contact forces). Pressure data were segmented by considering contact cells' anteroposterior location, and were used to compute 3D moments at foot joints. The mean values and 95% confidence intervals were plotted for each device per shoe condition. The peak values and times of forces and moments were computed per participant and trial under each condition, and were compared using mixed-effect tests. Test-retest reliability was analyzed by means of intraclass correlation coefficients. The curve profiles from both devices were similar, with higher joint moments for the instrumented insoles at the metatarsophalangeal joint (~26%), which were lower at the ankle (~8%) and midtarsal (~15%) joints, although the differences were nonsignificant. Not considering frictional forces resulted in ~20% lower peaks at the ankle moments compared to previous studies, which employed force plates. The device affected both shoe conditions in the same way, which suggests the interchangeability of measuring joint moments with one or the other device. This hypothesis was reinforced by the intraclass correlation coefficients, which were higher for the peak values, although only moderate-to-good. In short, both considered alternatives have drawbacks. Only the instrumented in-soles provided direct information about foot contact forces, but it was incomplete (evidenced by the difference in ankle moments between devices). However, recording ground reaction forces offers the advantage of enabling the consideration of contact friction forces (using force plates in series, or combining a pressure platform and a force plate to estimate friction forces and torque), which are less invasive than instrumented insoles (which may affect subjects' gait).

Microbiological Characterization of the Biofilms Colonizing Bioplastics in Natural Marine Conditions: A Comparison between PHBV and PLA

Biodegradable polymers offer a potential solution to marine pollution caused by plastic waste. The marine biofilms that formed on the surfaces of poly(lactide acid) (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were studied. Bioplastics were exposed for 6 months to marine conditions in the Mediterranean Sea, and the biofilms that formed on their surfaces were assessed. The presence of specific PLA and PHBV degraders was also studied. PHBV showed extensive areas with microbial accumulations and this led to higher microbial surface densities than PLA (4.75 vs. 5.16 log CFU/cm²). Both polymers' surfaces showed a wide variety of microbial structures, including bacteria, fungi, unicellular algae and choanoflagellates. A high bacterial diversity was observed, with differences between the two polymers, particularly at the phylum level, with over 70% of bacteria affiliated to three phyla. Differences in metagenome functions were also detected, revealing a higher presence of proteins involved in PHBV biodegradation in PHBV biofilms. Four bacterial isolates belonging to the Proteobacteria class were identified as PHBV degraders, demonstrating the presence of species involved in the biodegradation of this polymer in seawater. No PLA degraders were detected, confirming its low biodegradability in marine environments. This was a pilot study to establish a baseline for further studies aimed at comprehending the marine biodegradation of biopolymers.

Unveiling the Potential of BenzylethyleneAryl-Urea Scaffolds for the Design of New Onco Immunomodulating Agents

This work focuses on the development of thirteen benzylethylenearyl ureas and one carbamate. After the synthesis and purification of the compounds, we studied their antiproliferative action on cell lines, such as HEK-293, and cancer ones, such as HT-29, MCF-7 or A-549, on the immune Jurkat T-cells and endothelial cells HMEC-1. Compounds C.1, C.3, C.12 and C.14 were selected for further biological studies to establish their potential as immunomodulating agents. Some of the derivatives exhibited significant inhibitory effects on both targets: PD-L1 and VEGFR-2 in the HT-29 cell line, showing that urea C.12 is active against both targets. Some compounds could inhibit more than 50% of cancer cell proliferation compared to non-treated ones when assessed in co-cultures using HT-29 and THP-1 cells. In addition, they significantly reduced CD11b expression, which is a promising target for immune modulation in anticancer immunotherapies.

Exploring BenzylethoxyAryl Urea Scaffolds for Multitarget Immunomodulation Therapies

Thirteen benzylethoxyaryl ureas have been synthesized and biologically evaluated as multitarget inhibitors of VEGFR-2 and PD-L1 proteins to overcome resistance phenomena offered by cancer. The antiproliferative activity of these molecules on several tumor cell lines (HT-29 and A549), on the endothelial cell line HMEC-1, on immune cells (Jurkat T) and on the non-tumor cell line HEK-293 has been determined. Selective indexes (SI) have been also determined and compounds bearing p-substituted phenyl urea unit together with a diaryl carbamate exhibited high SI values. Further studies on these selected compounds to determine their potential as small molecule immune potentiators (SMIPs) and as antitumor agents have been performed. From these studies, we have concluded that the designed ureas have good tumor antiangiogenic properties, exhibit good inhibition of CD11b expression, and regulate pathways involved in CD8 T-cell activity. These properties suggest that these compounds could be potentially useful in the development of new cancer immune treatments.

Long Non-Coding RNAs, Extracellular Vesicles and Inflammation in Alzheimer's Disease

Alzheimer's Disease (AD) has currently no effective treatment; however, preventive measures have the potential to reduce AD risk. Thus, accurate and early prediction of risk is an important strategy to alleviate the AD burden. Neuroinflammation is a major factor prompting the onset of the disease. Inflammation exerts its toxic effect via multiple mechanisms. Amongst others, it is affecting gene expression via modulation of non-coding RNAs (ncRNAs), such as miRNAs. Recent evidence supports that inflammation can also affect long non-coding RNA (lncRNA) expression. While the association between miRNAs and inflammation in AD has been studied, the role of lncRNAs in neurodegenerative diseases has been less explored. In this review, we focus on lncRNAs and inflammation in the context of AD. Furthermore, since plasma-isolated extracellular vesicles (EVs) are increasingly recognized as an effective monitoring strategy for brain pathologies, we have focused on the studies reporting dysregulated lncRNAs in EVs isolated from AD patients and controls. The revised literature shows a positive association between pro-inflammatory lncRNAs and AD. However, the reports evaluating lncRNA alterations in EVs isolated from the plasma of patients and controls, although still limited, confirm the value of specific lncRNAs associated with AD as reliable biomarkers. This is an emerging field that will open new avenues to improve risk prediction and patient stratification, and may lead to the discovery of potential novel therapeutic targets for AD.