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1.
Artigo em Inglês | MEDLINE | ID: mdl-39028606

RESUMO

Mild cognitive impairment (MCI) and gait deficits are commonly associated with Parkinson's disease (PD). Early detection of MCI associated with Parkinson's disease (PD-MCI) and its biomarkers is critical to managing disability in PD patients, reducing caregiver burden and healthcare costs. Gait is considered a surrogate marker for cognitive decline in PD. However, gait kinematic and kinetic features in PD-MCI patients remain unknown. This study was designed to explore the difference in gait kinematics and kinetics during single-task and dual-task walking between PD patients with and without MCI. Kinematic and kinetic data of 90 PD patients were collected using 3D motion capture system. Differences in gait kinematic and kinetic gait features between groups were identified by using: first, univariate statistical analysis and then a supervised machine learning analysis. The findings of this study showed that the presence of MCI in PD patients is coupled with kinematic and kinetic deviations of gait cycle which may eventually identify two different phenotypes of the disease. Indeed, as shown by the demographical and clinical comparison between the two groups, PD-MCI patients were older and more impaired. Moreover, PD-MCI kinematic results showed that cognitive dysfunction coexists with more severe axial symptoms and an increase postural flexion. A lack of physiological distal-to-proximal shift in joint kinetics was evidenced in the PD phenotype associated with cognitive impairments.

2.
Breast Cancer ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811515

RESUMO

BACKGROUND: To assess contrast-enhanced mammography (CEM) in the management of BI-RADS3 breast architectural distortions (AD) in digital breast tomosynthesis (DBT). METHODS: We retrospectively reviewed 328 women with 332 ADs detected on DBT between 2017 and 2021 and selected those classified as BI-RADS3 receiving CEM as problem-solving. In CEM recombined images, we evaluated AD's contrast enhancement (CE) according to its presence/absence, type, and size. AD with enhancement underwent imaging-guided biopsy while AD without enhancement follow-up or biopsy if detected in high/intermediate-risk women. RESULTS: AD with enhancement were 174 (52.4%): 72 (41.4%) were malignant lesions, 102 (59.6%) false positive results: 28 (16%) B3 lesions, and 74 (42.5%) benign lesions. AD without enhancement were 158 (47.6%): 26 (16.5%) were subjected to biopsy (1 malignant and 25 benign) while the other 132 cases were sent to imaging follow-up, still negative after two years. CEM's sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and accuracy were 98.63%, 60.62%, 41.38%, 99.37%, and 68.98%. The AUC determined by ROC was 0.796 (95% CI, 0.749-0.844). CONCLUSION: CEM has high sensitivity and NPV in evaluating BI-RADS3 AD and can be a complementary tool in assessing AD, avoiding unnecessary biopsies without compromising cancer detection.

3.
Int J Prosthodont ; 0(0): 1-22, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758586

RESUMO

AIMS: The aim of this prospective study was to evaluate and compare the implant survival rate, marginal bone levels and prostheses failure rate, of three-unit fixed dental prostheses (FDPs) supported by three vs. two implants immediately loaded in the posterior area. MATERIAL AND METHODS: Partially edentulous patients in need of a three-unit implant supported FDP in the maxillary/mandibular posterior region were recruited and randomly split into two groups: Group 1 with three-unit FDP supported by three implants (Control); Group 2 with three-unit FDP supported by two implants (Test). Implants were inserted and immediately loaded with a temporary FDP. RESULTS: Sixty-three patients were included in the study. A total of 178 implants were placed and immediately loaded (128 maxillary/50 mandibular) to support 74 immediate provisional fixed prostheses (52 maxillary and 22 mandibular) delivered on the same day of implant insertion/placement; 30 in Group 1 and 44 in Group 2. The comparison of three vs. two implants resulted in comparable implant survival rate, marginal bone loss, and prostheses failure rate. All implants healed uneventfully with no adverse clinical and radiographical signs or symptoms except for one implant failure in Group 1 resulting in a cumulative success rate of 99,5%, 98,9% for Group 1 and 100% for Group 2 with a follow-up of 6-to-10 (mean 7 years). Once loaded, the implants remained in function from a minimum of 6 years to 10 years. CONCLUSIONS: Although more studies and larger sample sizes are needed to validate this study, the results showed no difference between the two Groups, demonstrating the potential viability of both clinical options.

4.
Ig Sanita Pubbl ; 80(2): 30-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38739439

RESUMO

Falls are a widespread concern in hospitals settings. In Italy, falls are the fourth frequent damage claim type after surgical, diagnostic and therapeutic error and 90% of falls are avoidable. The first necessary action for the prevention of falls consists in identifying the possible risk factors, in relation to the characteristics of the patient and those of the environment and the structure that hosts him, in terms of safety, organization and adequacy of the process welfare. In this work we wanted to evaluate the extent, frequency and characteristics of the phenomenon of falls in the population hospitalized at the Local Health Authority called "Roma 2", with the aim of analyzing the critical issues to allow the identification of possible preventive and improvement interventions as well as reducing the risk of falls.


Assuntos
Acidentes por Quedas , Gestão de Riscos , Humanos , Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Itália , Gestão de Riscos/métodos , Idoso , Masculino , Feminino , Fatores de Risco , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adulto
5.
Heliyon ; 10(7): e28723, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596118

RESUMO

Electrical impedance spectroscopy (EIS) stands as a widely employed characterization technique for studying muscular tissue in both physio/pathological conditions. This methodology commonly involves modeling tissues through equivalent electrical circuits, facilitating a correlation between electrical parameters and physiological properties. Within existing literature, diverse equivalent electrical circuits have been proposed, varying in complexity and fitting properties. However, to date, none have definitively proven to be the most suiTable for tissue impedance measurements. This study aims to outline a systematic methodology for EIS measurements and to compare the performances of three widely used electrical circuits in characterizing both physiological and pathological muscle tissue conditions. Results highlight that, for optimal fitting with electrical parameters relevant to tissue characterization, the choice of the circuit to be fitted closely hinges on the specific measurement objectives, including measurement parameters and associated physiological features. Naturally, this necessitates a balance between simplicity and fitting accuracy.

6.
Transl Med UniSa ; 26(1): 1-14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560616

RESUMO

Aims: This study delves into the two-year opioid prescription trends in the Local Sanitary Agency Naples 3 South, Campania Region, Italy. The research aims to elucidate prescribing patterns, demographics, and dosage categories within a population representing 1.7% of the national total. Perspectives on artificial intelligence research are discussed. Methods: From the original dataset, spanning from January 2022 to October 2023, we processed multiple variables including demographic data, medications, dosages, drug consumption, and administration routes. The dispensing quantity was calculated as defined daily doses (DDD). Results: The analysis reveals a conservative approach to opioid therapy. In subjects under the age of 20, prescriptions accounted for 2.1% in 2022 and declined to 1.4% in 2023. The drug combination paracetamol/codeine was the most frequently prescribed, followed by tapentadol. Approximately two-thirds of the consumption pertains to oral formulations. Transdermal formulations were 15% (fentanyl 9.8%, buprenorphine 5.1%) in 2022; and 16.6% (fentanyl 10%, buprenorphine 6.6%) in 2023. These data were confirmed by the DDD analysis. The trend analysis demonstrated a significant reduction ( p < 0.001) in the number of prescribed opioids from 2022 to 2023 in adults (40-69 years). The study of rapid-onset opioids (ROOs), drugs specifically used for breakthrough cancer pain, showed higher dosage (>267 mcg) consumption among women, whereas a lower dosage (<133 mcg) was calculated for men. Fentanyl pectin nasal spray accounted for approximately one-fifth of all ROOs. Conclusion: Despite limitations, the study provides valuable insights into prescribing practices involving an important study population. The findings underscore the need for tailored approaches to prescribing practices, recognizing the complexities of pain management in different contexts. This research can contribute to the ongoing discourse on opioid use, advocating for innovative strategies that optimize therapeutic outcomes while mitigating potential risks.

7.
Int J Oral Implantol (Berl) ; 17(1): 75-86, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501400

RESUMO

PURPOSE: To evaluate the survival and success rate of and the incidence of complications affecting implants inserted and immediately loaded in sites where an impacted tooth was present in the maxilla. MATERIALS AND METHODS: A total of 10 patients were treated and 14 implants were inserted, 4 in healed sites and 10 in extraction sites. The implant site preparation started in the crestal bone and continued in the enamel and dentine of the impacted tooth. The radiographic depth of implant penetration into the impacted tooth, peri-implant soft tissue and hard tissue condition at the 1-year follow-up and the last follow-up appointment, marginal bone loss at the 1-year follow-up and the last follow-up appointment, and the final aesthetic result were evaluated. RESULTS: The implants healed uneventfully with an adequate hard and soft tissue response and no adverse clinical or radiographic signs or symptoms. They were in function for a minimum of 3 and a maximum of 11 years (mean 7.2 years). CONCLUSION: Although further studies with a larger sample size are required to validate this unconventional approach, it can be considered a valuable clinical option to replace teeth in an area of impaction.


Assuntos
Implantes Dentários para Um Único Dente , Implantes Dentários , Carga Imediata em Implante Dentário , Dente Impactado , Humanos , Seguimentos , Resultado do Tratamento , Estudos Retrospectivos , Implantes Dentários/efeitos adversos , Dente Impactado/etiologia , Carga Imediata em Implante Dentário/efeitos adversos , Alvéolo Dental/cirurgia , Estética Dentária
8.
Proc Natl Acad Sci U S A ; 121(12): e2318716121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38483991

RESUMO

Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.

9.
Diagnostics (Basel) ; 14(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38535000

RESUMO

Occupational ergonomics aims to optimize the work environment and to enhance both productivity and worker well-being. Work-related exposure assessment, such as lifting loads, is a crucial aspect of this discipline, as it involves the evaluation of physical stressors and their impact on workers' health and safety, in order to prevent the development of musculoskeletal pathologies. In this study, we explore the feasibility of machine learning (ML) algorithms, fed with time- and frequency-domain features extracted from inertial signals (linear acceleration and angular velocity), to automatically and accurately discriminate safe and unsafe postures during weight lifting tasks. The signals were acquired by means of one inertial measurement unit (IMU) placed on the sternums of 15 subjects, and subsequently segmented to extract several time- and frequency-domain features. A supervised dataset, including the extracted features, was used to feed several ML models and to assess their prediction power. Interesting results in terms of evaluation metrics for a binary safe/unsafe posture classification were obtained with the logistic regression algorithm, which outperformed the others, with accuracy and area under the receiver operating characteristic curve values of up to 96% and 99%, respectively. This result indicates the feasibility of the proposed methodology-based on a single inertial sensor and artificial intelligence-to discriminate safe/unsafe postures associated with load lifting activities. Future investigation in a wider study population and using additional lifting scenarios could confirm the potentiality of the proposed methodology, supporting its applicability in the occupational ergonomics field.

10.
Chemistry ; 30(18): e202303631, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38059669

RESUMO

Carbon dots (CDs) are an emerging class of carbon nanoparticles, which for their characteristics have found applications in many fields such as catalysis, materials and biomedicine. Within this context, the application of CDs as antibacterial agents has received much attention in very recent years, while their use as antifungal nanoparticles has been scarcely investigated. Here we report a systematic investigation of the surface functional groups of CDs to study their influence on these nanoparticles' against Candida albicans. Three classes of CDs have been synthesised and fully characterized. A thorough in vitro and in vivo biological screening against C. albicans was performed to test their antifungal, antiadhesion and antibiofilm formation activities. Moreover, the interaction with C. albicans cells was investigated by microscopic analysis. Our results evidence how the presence of a positively polarised surface results crucial for the internalization into COS-7 cells. Positively charged nanoparticles were also able to inhibit adhesion and biofilm formation, to interact with the cellular membrane of C. albicans, and to increase the survival of G. mellonella infected larvae after the injection with positive nanoparticles. The antifungal activity of CDs and their extremely low toxicity may represent a new strategy to combat infections sustained by C.albicans.


Assuntos
Antifúngicos , Candida albicans , Animais , Antifúngicos/farmacologia , Carbono , Biofilmes , Larva , Testes de Sensibilidade Microbiana
11.
Gut ; 73(3): 496-508, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-37758326

RESUMO

OBJECTIVE: Cytotoxic agents are the cornerstone of treatment for patients with advanced intrahepatic cholangiocarcinoma (iCCA), despite heterogeneous benefit. We hypothesised that the pretreatment molecular profiles of diagnostic biopsies can predict patient benefit from chemotherapy and define molecular bases of innate chemoresistance. DESIGN: We identified a cohort of advanced iCCA patients with comparable baseline characteristics who diverged as extreme outliers on chemotherapy (survival <6 m in rapid progressors, RP; survival >23 m in long survivors, LS). Diagnostic biopsies were characterised by digital pathology, then subjected to whole-transcriptome profiling of bulk and geospatially macrodissected tissue regions. Spatial transcriptomics of tumour-infiltrating myeloid cells was performed using targeted digital spatial profiling (GeoMx). Transcriptome signatures were evaluated in multiple cohorts of resected cancers. Signatures were also characterised using in vitro cell lines, in vivo mouse models and single cell RNA-sequencing data. RESULTS: Pretreatment transcriptome profiles differentiated patients who would become RPs or LSs on chemotherapy. Biologically, this signature originated from altered tumour-myeloid dynamics, implicating tumour-induced immune tolerogenicity with poor response to chemotherapy. The central role of the liver microenviroment was confrmed by the association of the RPLS transcriptome signature with clinical outcome in iCCA but not extrahepatic CCA, and in liver metastasis from colorectal cancer, but not in the matched primary bowel tumours. CONCLUSIONS: The RPLS signature could be a novel metric of chemotherapy outcome in iCCA. Further development and validation of this transcriptomic signature is warranted to develop precision chemotherapy strategies in these settings.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Animais , Camundongos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Perfilação da Expressão Gênica , Transcriptoma , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/metabolismo
12.
Sensors (Basel) ; 23(24)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38139705

RESUMO

The use of wearable sensors for calculating gait parameters has become increasingly popular as an alternative to optoelectronic systems, currently recognized as the gold standard. The objective of the study was to evaluate the agreement between the wearable Opal system and the optoelectronic BTS SMART DX system for assessing spatiotemporal gait parameters. Fifteen subjects with progressive supranuclear palsy walked at their self-selected speed on a straight path, and six spatiotemporal parameters were compared between the two measurement systems. The agreement was carried out through paired data test, Passing Bablok regression, and Bland-Altman Analysis. The results showed a perfect agreement for speed, a very close agreement for cadence and cycle duration, while, in the other cases, Opal system either under- or over-estimated the measurement of the BTS system. Some suggestions about these misalignments are proposed in the paper, considering that Opal system is widely used in the clinical context.


Assuntos
Paralisia Supranuclear Progressiva , Dispositivos Eletrônicos Vestíveis , Humanos , Paralisia Supranuclear Progressiva/diagnóstico , Marcha , Caminhada
13.
Front Bioeng Biotechnol ; 11: 1282024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38149173

RESUMO

Introduction: The aging population poses significant challenges to healthcare systems globally, necessitating a comprehensive understanding of age-related changes affecting physical function. Age-related functional decline highlights the urgency of understanding how tissue composition changes impact mobility, independence, and quality of life in older adults. Previous research has emphasized the influence of muscle quality, but the role of tissue composition asymmetry across various tissue types remains understudied. This work develops asymmetry indicators based on muscle, connective and fat tissue extracted from cross-sectional CT scans, and shows their interplay with BMI and lower extremity function among community-dwelling older adults. Methods: We used data from 3157 older adults from 71 to 98 years of age (mean: 80.06). Tissue composition asymmetry was defined by the differences between the right and left sides using CT scans and the non-Linear Trimodal Regression Analysis (NTRA) parameters. Functional mobility was measured through a 6-meter gait (Normal-GAIT and Fast-GAIT) and the Timed Up and Go (TUG) performance test. Statistical analysis included paired t-tests, polynomial fitting curves, and regression analysis to uncover relationships between tissue asymmetry, age, and functional mobility. Results: Findings revealed an increase in tissue composition asymmetry with age. Notably, muscle and connective tissue width asymmetry showed significant variation across age groups. BMI classifications and gait tasks also influenced tissue asymmetry. The Fast-GAIT task demonstrated a substantial separation in tissue asymmetry between normal and slow groups, whereas the Normal-GAIT and the TUG task did not exhibit such distinction. Muscle quality, as reflected by asymmetry indicators, appears crucial in understanding age-related changes in muscle function, while fat and connective tissue play roles in body composition and mobility. Discussion: Our study emphasizes the importance of tissue asymmetry indicators in understanding how muscle function changes with age in older individuals, demonstrating their role as risk factor and their potential employment in clinical assessment. We also identified the influence of fat and connective tissue on body composition and functional mobility. Incorporating the NTRA technology into clinical evaluations could enable personalized interventions for older adults, promoting healthier aging and maintaining physical function.

14.
Sci Rep ; 13(1): 22462, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38105340

RESUMO

Functional bone marrow studies have focused primarily on hematopoietic progenitors, leaving limited knowledge about other fragile populations, such as bone marrow adipocytes (BMAds) and megakaryocytes. The isolation of these cells is challenging due to rupture susceptibility and large size. We introduce here a label-free cytometry microsystem, MarrowCellDLD, based on deterministic lateral displacement. MarrowCellDLD enables the isolation of large, fragile BM-derived cells based on intrinsic size properties while preserving their viability and functionality. Bone marrow adipocytes, obtained from mouse and human stromal line differentiation, as well as megakaryocytes, from primary human CD34+ hematopoietic stem and progenitor cells, were used for validation. Precise micrometer-range separation cutoffs were adapted for each cell type. Cells were sorted directly in culture media, without pre-labeling steps, and with real-time imaging for quality control. At least 106 cells were retrieved intact per sorting round. Our method outperformed two FACS instruments in purity and yield, particularly for large cell size fractions. MarrowCellDLD represents a non-destructive sorting tool for large, fragile BM-derived cells, facilitating the separation of pure populations of BMAds and megakaryocytes to further investigate their physiological and pathological roles.


Assuntos
Medula Óssea , Células-Tronco Hematopoéticas , Humanos , Camundongos , Animais , Microfluídica , Separação Celular/métodos , Megacariócitos , Antígenos CD34 , Células da Medula Óssea , Diferenciação Celular , Citometria de Fluxo
15.
Sensors (Basel) ; 23(19)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37836872

RESUMO

Patients affected with type 1 diabetes and a non-negligible number of patients with type 2 diabetes are insulin dependent. Both the injection technique and the choice of the most suitable needle are fundamental for allowing them to have a good injection experience. The needles may differ in several parameters, from the length and diameter, up to the forces required to perform the injection and to some geometrical parameters of the needle tip (e.g., number of facets or bevels). The aim of the research is to investigate whether an increased number of bevels could decrease forces and energy involved in the insertion-extraction cycle, thus potentially allowing patients to experience lower pain. Two needle variants, namely, 31 G × 5 mm and 32 G × 4 mm, are considered, and experimental tests are carried out to compare 3-bevels with 5-bevels needles for both the variants. The analysis of the forces and energy for both variants show that the needles with 5 bevels require a statistically significant lower drag or sliding force (p-value = 0.040 for the 31 G × 5 mm needle and p-value < 0.001 for 32 G × 4 mm), extraction force (p-value < 0.001 for both variants), and energy (p-value < 0.001 for both variants) during the insertion-extraction cycle. As a result, 3-bevels needles do not have the same functionality of 5-bevels needles, show lower capacity of drag and extraction, and can potentially be related to more painful injection experience for patients.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Injeções Subcutâneas , Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina , Dor , Agulhas
16.
RSC Adv ; 13(42): 29308-29315, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37809030

RESUMO

Graphene oxide (GO) is known to be a 2D metastable nanomaterial that can be reconstructed under thermal annealing into distinct oxidized and graphitic phases. Up to now, such phase transformation, mainly related to epoxide and hydroxyl functional groups, has been usually achieved by thermally treating layers of GO in the solid state. Here, we present the mild annealing of GO dispersed in an aqueous medium, performed at two temperatures, 50 °C and 80 °C, for different intervals of time. We show experimental evidences of the epoxide instability in the presence of water by means of XPS, cyclic voltammetry and Raman spectroscopy, demonstrating the reorganization of epoxide and hydroxyl moieties initiated by water molecules. In fact, at 50 °C an increase in oxygen content is detected in all annealed samples compared to untreated GO, with a transformation of epoxide groups into vicinal diols. On the other hand, at 80 °C the oxygen content decreases towards the initial value since the vicinal diols, previously formed, transform into single hydroxyls and C[double bond, length as m-dash]C bonds. Moreover, the higher temperature annealing likely favours oxygenated functional groups rearrangements and clustering, in accordance with the literature, leading to a higher electron affinity and conductivity of the graphenic network.

17.
Bioengineering (Basel) ; 10(9)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37760205

RESUMO

Manual material handling and load lifting are activities that can cause work-related musculoskeletal disorders. For this reason, the National Institute for Occupational Safety and Health proposed an equation depending on the following parameters: intensity, duration, frequency, and geometric characteristics associated with the load lifting. In this paper, we explore the feasibility of several Machine Learning (ML) algorithms, fed with frequency-domain features extracted from electromyographic (EMG) signals of back muscles, to discriminate biomechanical risk classes defined by the Revised NIOSH Lifting Equation. The EMG signals of the multifidus and erector spinae muscles were acquired by means of a wearable device for surface EMG and then segmented to extract several frequency-domain features relating to the Total Power Spectrum of the EMG signal. These features were fed to several ML algorithms to assess their prediction power. The ML algorithms produced interesting results in the classification task, with the Support Vector Machine algorithm outperforming the others with accuracy and Area under the Receiver Operating Characteristic Curve values of up to 0.985. Moreover, a correlation between muscular fatigue and risky lifting activities was found. These results showed the feasibility of the proposed methodology-based on wearable sensors and artificial intelligence-to predict the biomechanical risk associated with load lifting. A future investigation on an enriched study population and additional lifting scenarios could confirm the potential of the proposed methodology and its applicability in the field of occupational ergonomics.

18.
Micromachines (Basel) ; 14(9)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37763906

RESUMO

A minimally-invasive manipulator characterized by hyper-redundant kinematics and embedded sensing modules is presented in this work. The bending angles (tilt and pan) of the robot tip are controlled through tendon-driven actuation; the transmission of the actuation forces to the tip is based on a Bowden-cable solution integrating some channels for optical fibers. The viability of the real-time measurement of the feedback control variables, through optoelectronic acquisition, is evaluated for automated bending of the flexible endoscope and trajectory tracking of the tip angles. Indeed, unlike conventional catheters and cannulae adopted in neurosurgery, the proposed robot can extend the actuation and control of snake-like kinematic chains with embedded sensing solutions, enabling real-time measurement, robust and accurate control of curvature, and tip bending of continuum robots for the manipulation of cannulae and microsurgical instruments in neurosurgical procedures. A prototype of the manipulator with a length of 43 mm and a diameter of 5.5 mm has been realized via 3D printing. Moreover, a multiple regression model has been estimated through a novel experimental setup to predict the tip angles from measured outputs of the optoelectronic modules. The sensing and control performance has also been evaluated during tasks involving tip rotations.

19.
Gels ; 9(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37623076

RESUMO

In this study, we present the synthesis of a novel peptide-based magnetogel obtained through the encapsulation of γ-Fe2O3-polyacrylic acid (PAA) nanoparticles (γ-Fe2O3NPs) into a hydrogel matrix, used for enhancing the ability of the hydrogel to remove Cr(III), Co(II), and Ni(II) pollutants from water. Fmoc-Phe (Fluorenylmethoxycarbonyl-Phenylalanine) and diphenylalanine (Phe2) were used as starting reagents for the hydrogelator (Fmoc-Phe3) synthesis via an enzymatic method. The PAA-coated magnetic nanoparticles were synthesized in a separate step, using the co-precipitation method, and encapsulated into the peptide-based hydrogel. The resulting organic/inorganic hybrid system (γ-Fe2O3NPs-peptide) was characterized with different techniques, including FT-IR, Raman, UV-Vis, DLS, ζ-potential, XPS, FESEM-EDS, swelling ability tests, and rheology. Regarding the application in heavy metals removal from aqueous solutions, the behavior of the obtained magnetogel was compared to its precursors and the effect of the magnetic field was assessed. Four different systems were studied for the separation of heavy metal ions from aqueous solutions, including (1) γ-Fe2O3NPs stabilized with PAA, (γ-Fe2O3NPs); (2) Fmoc-Phe3 hydrogel (HG); (3) γ-Fe2O3NPs embedded in peptide magnetogel (γ-Fe2O3NPs@HG); and (4) γ-Fe2O3NPs@HG in the presence of an external magnetic field. To quantify the removal efficiency of these four model systems, the UV-Vis technique was employed as a fast, cheap, and versatile method. The results demonstrate that both Fmoc-Phe3 hydrogel and γ-Fe2O3NPs peptide magnetogel can efficiently remove all the tested pollutants from water. Interestingly, due to the presence of magnetic γ-Fe2O3NPs inside the hydrogel, the removal efficiency can be enhanced by applying an external magnetic field. The proposed magnetogel represents a smart multifunctional nanosystem with improved absorption efficiency and synergic effect upon applying an external magnetic field. These results are promising for potential environmental applications of γ-Fe2O3NPs-peptide magnetogels to the removal of pollutants from aqueous media.

20.
Bioengineering (Basel) ; 10(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37508862

RESUMO

Mathematical models can improve the understanding of physiological systems behaviour, which is a fundamental topic in the bioengineering field. Having a reliable model enables researchers to carry out in silico experiments, which require less time and resources compared to their in vivo and in vitro counterparts. This work's objective is to capture the characteristics that a nonlinear dynamical mathematical model should exhibit, in order to describe physiological control systems at different scales. The similarities among various negative feedback physiological systems have been investigated and a unique general framework to describe them has been proposed. Within such a framework, both the existence and stability of equilibrium points are investigated. The model here introduced is based on a closed-loop topology, on which the homeostatic process is based. Finally, to validate the model, three paradigmatic examples of physiological control systems are illustrated and discussed: the ultrasensitivity mechanism for achieving homeostasis in biomolecular circuits, the blood glucose regulation, and the neuromuscular reflex arc (also referred to as muscle stretch reflex). The results show that, by a suitable choice of the modelling functions, the dynamic evolution of the systems under study can be described through the proposed general nonlinear model. Furthermore, the analysis of the equilibrium points and dynamics of the above-mentioned systems are consistent with the literature.

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