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1.
J Spine Surg ; 10(2): 214-223, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38974487

RESUMO

Background: The absence of consensus for prophylaxis of venous thromboembolism (VTE) in spine surgery underscores the importance of identifying patients at risk. This study incorporated machine learning (ML) models to assess key risk factors of VTE in patients who underwent posterior spinal instrumented fusion. Methods: Data was collected from the IBM MarketScan Database [2009-2021] for patients ≥18 years old who underwent spinal posterior instrumentation (3-6 levels), excluding traumas, malignancies, and infections. VTE incidence (deep vein thrombosis and pulmonary embolism) was recorded 90-day post-surgery. Risk factors for VTE were investigated and compared through several ML models including logistic regression, linear support vector machine (LSVM), random forest, XGBoost, and neural networks. Results: Among the 141,697 patients who underwent spinal fusion with posterior instrumentation (3-6 levels), the overall 90-day VTE rate was 3.81%. The LSVM model demonstrated the best prediction with an area under the curve (AUC) of 0.68. The most important features for prediction of VTE included remote history of VTE, diagnosis of chronic hypercoagulability, metastatic cancer, hemiplegia, and chronic renal disease. Patients who did not have these five key risk factors had a 90-day VTE rate of 2.95%. Patients who had an increasing number of key risk factors had subsequently higher risks of postoperative VTE. Conclusions: The analysis of the data with different ML models identified 5 key variables that are most closely associated with VTE. Using these variables, we have developed a simple risk model with additive odds ratio ranging from 2.80 (1 risk factor) to 46.92 (4 risk factors) over 90 days after posterior spinal fusion surgery. These findings can help surgeons risk-stratify their patients for VTE risk, and potentially guide subsequent chemoprophylaxis.

2.
Value Health ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38977195

RESUMO

OBJECTIVES: To accurately capture informal care in healthcare evaluations, rigorous approaches are required to measure and value this important care component. In this systematic review and meta-analysis, we intended to summarize the current methods of measuring and valuing informal care costs in healthcare evaluations (full and partial healthcare evaluations, including cost of illness and cost analysis) in stroke. METHODS: A systematic search was conducted in Medline, Embase, EconLIT, and CINAHL. We used EndNote 20, Research Screener, and Covidence platforms for screening and data extraction. A meta-analysis was performed on informal care hours, and a sub-group meta-analysis was conducted based on stroke severity. RESULTS: A total of 31 articles were included in the qualitative synthesis. There was variation among the studies in the informal care measurement and valuation approaches. The meta-analysis of studies where data on informal care hours were available showed an estimate of informal care hours of 25.76 per week (95% Confidence interval [CI]: 13.36-38.16 with a high heterogeneity (I2=99.97%). The overall risk of bias in the studies was assessed as low. CONCLUSIONS: Standardizing the measurement and valuation of informal care costs is essential for improving the consistency and comparability of economic evaluations. Pilot studies that incorporate standardized informal care cost valuation methods can help identify any practical challenges and capture the impact of informal care more accurately.

3.
Med Phys ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977285

RESUMO

BACKGROUND: The dynamic collimation system (DCS) provides energy layer-specific collimation for pencil beam scanning (PBS) proton therapy using two pairs of orthogonal nickel trimmer blades. While excellent measurement-to-calculation agreement has been demonstrated for simple cube-shaped DCS-trimmed dose distributions, no comparison of measurement and dose calculation has been made for patient-specific treatment plans. PURPOSE: To validate a patient-specific quality assurance (PSQA) process for DCS-trimmed PBS treatment plans and evaluate the agreement between measured and calculated dose distributions. METHODS: Three intracranial patient cases were considered. Standard uncollimated PBS and DCS-collimated treatment plans were generated for each patient using the Astroid treatment planning system (TPS). Plans were recalculated in a water phantom and delivered at the Miami Cancer Institute (MCI) using an Ion Beam Applications (IBA) dedicated nozzle system and prototype DCS. Planar dose measurements were acquired at two depths within low-gradient regions of the target volume using an IBA MatriXX ion chamber array. RESULTS: Measured and calculated dose distributions were compared using 2D gamma analysis with 3%/3 mm criteria and low dose threshold of 10% of the maximum dose. Median gamma pass rates across all plans and measurement depths were 99.0% (PBS) and 98.3% (DCS), with a minimum gamma pass rate of 88.5% (PBS) and 91.2% (DCS). CONCLUSIONS: The PSQA process has been validated and experimentally verified for DCS-collimated PBS. Dosimetric agreement between the measured and calculated doses was demonstrated to be similar for DCS-collimated PBS to that achievable with noncollimated PBS.

4.
Brachytherapy ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38964977

RESUMO

PURPOSE: High dose-rate (HDR) brachytherapy is integral for the treatment of numerous cancers. Preclinical studies involving HDR brachytherapy are limited. We aimed to describe a novel platform allowing multi-modality studies with clinical HDR brachytherapy and external beam irradiators, establish baseline dosimetry standard of a preclinical orthovoltage irradiator, to determine accurate dosimetric methods. METHODS: A dosimetric assessment of a commercial preclinical irradiator was performed establishing the baseline dosimetry goals for clinical irradiators. A 3D printed platform was then constructed with 14 brachytherapy channels at 1cm spacing to accommodate a standard tissue culture plate at a source-to-cell distance (SCD) of 1 cm or 0.4 cm. 4-Gy CT-based treatment plans were created in clinical treatment planning software and delivered to 96-well tissue culture plates using an Ir192 source or a clinical linear accelerator. Standard calculation models for HDR brachytherapy and external beam were compared to corresponding deterministic model-based dose calculation algorithms (MBDCAs). Agreement between predicted and measured dose was assessed with 2D-gamma passing rates to determine the best planning methodology. RESULTS: Mean (±standard deviation) and median dose measured across the plate for the preclinical irradiator was 423.7 ± 8.5 cGy and 430.0 cGy. Mean percentage differences between standard and MBDCA dose calculations were 9.4% (HDR, 1 cm SCD), 0.43% (HDR, 0.4 cm SCD), and 2.4% (EBRT). Predicted and measured dose agreement was highest for MBDCAs for all modalities. CONCLUSION: A 3D-printed tissue culture platform can be used for multi-modality irradiation studies with great accuracy. This tool will facilitate preclinical studies to reveal biologic differences between clinically relevant radiation modalities.

5.
Arch Pharm (Weinheim) ; : e2400067, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967191

RESUMO

The development of targeted phthalazine-1,4-dione acetylcholinesterase (AChE) inhibitors for treating Alzheimer's disease involved the synthesis of 32 compounds via a multistage process. Various analytical techniques confirmed the compounds' identities. Thirteen compounds were found to inhibit AChE by more than 50% without affecting butyrylcholinesterase (BChE). Among these, three compounds, 8m, 8n, and 8p, exhibited extraordinary activity similar to donepezil, a reference AChE inhibitor. During enzyme kinetic studies, compound 8n, displaying the highest AChE inhibitory activity, underwent evaluation at three concentrations (2 × IC50, IC50, and IC50/2). Lineweaver-Burk plots indicated mixed inhibition activity for compound 8n against AChE, suggesting a combination of competitive and noncompetitive characteristics. Additionally, effective derivatives 8m, 8n, and 8p exhibited high blood-brain barrier (BBB) permeability in in vitro parallel artificial membrane permeability assay tests. Molecular docking studies revealed that these compounds bind to the enzyme's active site residues in a position similar to donepezil. Molecular dynamic simulations confirmed the stability of the protein-ligand system, and the chemical reactivity characteristics of the compounds were investigated using density functional theory. The compounds' wide energy gaps suggest stability and therapeutic potential. This research represents a significant step toward finding a potential cure for Alzheimer's disease. However, further research and testing are required to determine the compounds' safety and efficacy. The unique structure of phthalazine derivatives makes them suitable for various biological activities, and these compounds show promise for developing effective drugs for treating Alzheimer's disease. Overall, the development of these targeted compounds is a crucial advancement in the search for an effective treatment for Alzheimer's disease.

6.
J Mol Model ; 30(8): 251, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967703

RESUMO

CONTEXT: Silicon carbide nanowires (SiCNWs) are considered a promising alternative material for application in lithium-ion batteries, with researchers striving to develop new electrode materials that exhibit high capacity and high charge/discharge rate performance. To gain a deeper understanding of the application of SiCNWs in semiconductor material science and energy supply fields, we investigated the effects of nanoscale and surface lithiation on the electrical and mechanical properties of SiCNWs grown along the [111] direction. First-principles calculation was used to study their geometries, electronic structures, and associated electrochemical properties. Herein, we considered SiCNWs with full hydrogen passivation, full lithium passivation, and mixed passivation at different sizes. The formation energy indicates that the stability of SiCNWs increases with the increasing diameter, and the surface-lithiated SiC nanowires (Li-SiCNWs) are found to be energetically stable. The mixed passivated SiCNWs exhibit the properties of indirect band gap with the increase of lithium atoms on the surface, while the fully lithium passivated nanowires exhibit metallic behavior. Charge analysis shows that a portion of the electrons on the lithium atoms are transferred to the surface atoms of the nanowires and electrons prefer to cluster more near the C atoms. Additionally, Li-SiCNWs still have good mechanical resistance during the lithiation process. The stable open-circuit voltage range and theoretical capacity of these SiCNWs indicate their suitability as anode materials. METHOD: In this study, Materials Studio 8.0 was used to construct the models of the SiCNWs. And all the density functional theory (DFT) calculations were performed by the Vienna ab initio Simulation Package (VASP). The self-consistent field calculations are performed over a Monkhorst-Pack net of 1 × 1 × 6 k-points. The energy convergence criteria for the self-consistent field calculation were set to 10-5 eV/atom with a cutoff energy of 400 eV.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38967775

RESUMO

PURPOSE: To evaluate formulas for intraocular lens (IOL) calculation in children undergoing lens extraction and IOL implantation. METHODS: Retrospective, consecutive case series at the Department of Ophthalmology, Goethe University Frankfurt, Germany. We included eyes that received lens extraction and IOL implantation (SN60AT, Alcon, Fort Worth, TX) due to congenital or juvenile cataract. Preoperative assessments included biometry (IOLMaster 500/700, Carl Zeiss Meditec, Germany). To evaluate the measurements, we compared the mean prediction error (MPE), mean and median absolute prediction error (MAE, MedAE) of six different formulas, and number of eyes within ± 0.5, ± 1.0, ± 2.0D of target refraction. Postoperative spherical equivalent was measured by retinoscopy 4-12 weeks after surgery. RESULTS: 66 eyes matched our inclusion criteria with a mean age of 6.3 years ± 3.2. MedAE was lowest in SRK/T (0.55D ± 1.08) followed by Holladay I (0.75D ± 1.00), EVO 2.0 (0.80D ± 0.89), Barrett Universal II (BUII, 0.86D ± 1.00), Hoffer Q (0.97 D ± 0.94), and Haigis (1.10D ± 0.95). Regarding eyes within ± 0.5D SRK/T (45.5.%, 30 eyes) performed best, followed by Holladay I (36.4%, 24 eyes), EVO 2.0 and BUII (each 34.8%, 23 eyes). There was a myopic shift seen in all formulas (MPE: -0.21 to -0.90D). CONCLUSION: Using modern formulas, or even AI formulas, for IOL calculation in children's eyes does barely improve predictability of the postoperative refraction. A myopic shift can be found for all formulas. However, specific formulas like SRK/T seem to better anticipate this.

8.
Beilstein J Org Chem ; 20: 1444-1452, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952960

RESUMO

Although hypervalent iodine(III) reagents have become staples in organic chemistry, the exploration of their isoelectronic counterparts, namely hypervalent bromine(III) and chlorine(III) reagents, has been relatively limited, partly due to challenges in synthesizing and stabilizing these compounds. In this study, we conduct a thorough examination of both homolytic and heterolytic bond dissociation energies (BDEs) critical for assessing the chemical stability and functional group transfer capability of cyclic hypervalent halogen compounds using density functional theory (DFT) analysis. A moderate linear correlation was observed between the homolytic BDEs across different halogen centers, while a strong linear correlation was noted among the heterolytic BDEs across these centers. Furthermore, we developed a predictive model for both homolytic and heterolytic BDEs of cyclic hypervalent halogen compounds using machine learning algorithms. The results of this study could aid in estimating the chemical stability and functional group transfer capabilities of hypervalent bromine(III) and chlorine(III) reagents, thereby facilitating their development.

9.
Clin Res Cardiol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953945

RESUMO

BACKGROUND: The relationship between inflammatory bowel disease (IBD) and cardiovascular outcomes among pregnant women has yet to be thoroughly investigated. Our aim is to assess the odds of cardiovascular disease and cardiac arrhythmias during hospital admissions for delivery and identify contributing factors associated with cardiovascular complications in pregnant women with IBD. METHODS: We performed a retrospective analysis of data from the National Inpatient Sample, obtained from delivery admissions of pregnant women with and without IBD, identified via International Classification of Diseases codes, from 2009 to 2019. Using a regression model, we compared the odds of cardiovascular complications between these two groups, adjusting for traditional cardiovascular risk factors as confounding variables. RESULTS: Our study included 71,361 pregnancies with IBD and 41,117,443 pregnancies without this condition. The incidence of IBD in pregnancy rose near three-fold increase over the decade. In comparison to pregnancies without IBD, those involving pregnant patients with IBD exhibited an increased likelihood of encountering cardiovascular complications, with an adjusted odds ratio (AOR) of 1.37 (95% CI, 1.29-1.46). This heightened risk encompasses a range of conditions, including peripartum cardiomyopathy (AOR, 9.45; 95% CI, 3.86-23.15), cardiac arrhythmias (AOR, 2.03; 95% CI, 1.59-2.60), and hypertensive disorders of pregnancy (AOR, 1.51; 95% CI, 1.37-1.66), notably preeclampsia, eclampsia, and the syndrome of hemolysis, elevated liver enzymes, and low platelet count (HELLP syndrome). Pregnancies with IBD were also associated with three-fold higher odds of venous thromboembolism (AOR, 3.91; 95% CI, 1.45-10.48). CONCLUSIONS: Pregnant patients with IBD had an increased odds of cardiovascular complications during delivery admissions, independent of traditional cardiovascular risk factors. Further research is needed to elucidate the underlying mechanisms and develop targeted prevention strategies for this high-risk population.

10.
Acta Ophthalmol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994803

RESUMO

PURPOSE: To evaluate whether the intraocular lens (IOL) calculation of the fellow eye (FE) can be used in eyes undergoing combined phacovitrectomy. METHODS: In this retrospective, consecutive case series, we enrolled patients who underwent combined phacovitrectomy with silicone oil removal and IOL implantation at the Goethe-University. Preoperative examinations included biometry (IOLMaster 700; Carl Zeiss). We used the IOL calculation of the FE (FE group) to calculate the prediction error compared with the IOL calculation using only the axial length (AL) of the FE (AL-FE group), as well as using the AL of the operated eye (OE group) in addition to the measurable biometric parameters. IOL calculation was performed using the Barrett Universal II formula. We compared the mean (MAE) and median absolute prediction error (MedAE) with each other. Furthermore, the number of eyes with ±0.50, ±1.00 and ±2.00 dioptres (D) deviation from the target refraction was compared. RESULTS: In total, 79 eyes of 79 patients were included. MedAE was lowest in the OE group (0.41 D), followed by FE group (1.00 D) and AL-FE group (1.02 D). Comparison between the AL-FE and FE groups showed no statistically significant difference (p = 0.712). Comparing eyes within ±0.50 D of the target refraction, the OE group (63.3%) performed best, followed by the AL-FE group (27.8%) and the FE group (26.6%). CONCLUSION: Our results indicate no clinically relevant difference between using the IOL calculation of the FE versus using only the AL of the FE in addition to the measurable parameters for the IOL calculation. A two-step procedure should always be strived for.

11.
J Colloid Interface Sci ; 676: 89-100, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39018814

RESUMO

Graphite carbon nitride (g-C3N4) is a promising photocatalyst,but its inadequate reactive sites, weak visible light responsiveness, and sluggish separation of photogenerated carriers hamperthe improvement of photodegradation efficiency. In this work, potassium (K) and halogen atoms co-modified g-C3N4 photocatalysts (CN-KX, X = F, Cl, Br, I) were constructed to adjust the electrical and band structure for enhanced generation of reactive oxygen species. Through an integration of theoretical calculation and experimental exploration, the doping sites of halogen atoms as well as the evolution of crystal, band, and electronic structures were investigated. The results show that a covalent bond is formed between the F atom and the C atom, substitution of the N atom occurs with a Cl atom, and doping of Br, I, or K atoms takes place at the interstitial site. CN-KX photocatalysts exhibits lower band gap, faster photogenerated electron migration, and enhanced photocatalytic activity. Specifically, the CN-KI photocatalyst exhibits the highest photodegradation efficiency because of its smaller interplanar spacing, formation of the midgap state, and adjustable local electron density. Equally, the doping of I atom not only provides a stable adsorption site for oxygen (O2) but also facilitates electron transfer, promoting the production of superoxide radicals (O2-) and contributing to the process of photodegradation.

12.
Phys Med Biol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019051

RESUMO

OBJECTIVE: To allow the estimation of secondary cancer risks from radiation therapy treatment plans in a comprehensive and user-friendly Monte Carlo framework. Approach: Patient planning CTs were extended superior-inferior using the ICRP Publication 145 computational mesh phantoms and skeletal matching. Dose distributions were calculated with the TOPAS Monte Carlo system using novel mesh capabilities and the DICOM-RT interface. Finally, in-field and out-of-field cancer risk was calculated using both sarcoma and carcinoma risk models with two alternative parameter sets. Main results: The TOPAS Monte Carlo framework was extended to facilitate epidemiological studies on radiation-induced cancer risk. The framework is efficient and allows automated analysis of large datasets. Out-of-field organ dose was small compared to in-field dose, but the risk estimates indicate a non-negligible contribution to the total radiation induced cancer risk. Significance: The implementation of anatomical extension, mesh phantom capabilities, and cancer risk models into the TOPAS Monte Carlo system makes state-of-the-art out-of-field dose calculation and risk estimation accessible to a large pool of users while facilitating further refinement of risk models and sensitivity analysis of patient specific treatment options.

13.
Chemosphere ; : 142855, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019195

RESUMO

This study aimed to design an efficient and easily collected/regenerated adsorbent for trace concentration sulfamethoxazole (SMX) removal to eliminate its negative impacts on human health, reduce the risk of adsorbed SMX release and boost the reusability of adsorbent. Various multiple modified sludge-derived biochars (SBC) were synthesized in this work and applied to adsorb trace level SMX. The results demonstrated that hydrothermal N-doping, magnetization coupled with ball milling co-functionalized SBC (BMNSBC) displayed the greater adsorption ability for SMX. The maximum adsorption capacity of BMNSBC for SMX calculated by Langmuir model was 1.02×105 µg/g, which was 12.9 times of SBC. Characterization combined with adsorption experiments (e.g., models fitting) and DFT calculation confirmed that π-π conjugation, Lewis acid-base, pore filling and Fe3O4 complexation were the primary forces driving SMX binding to BMNSBC. These diversified physicochemical forces contributed to the fine anti-interference of BMNSBC to background substances (e.g., inorganic compounds and organic matter) and its remarkable adsorption ability for SMX in diverse real waters. The great magnetization strength of BMNSBC was advantage for its collection and efficient regeneration by NaOH desorption. Additionally, BMNSBC exhibited a outstanding security in view of its low leaching levels of iron (Fe) and total nitrogen (TN). The multiple superiority of BMNSBC enable it to be a prospective material for emerging contaminants (e.g., SMX) purification, also offering a feasible disposal approach for municipal waste (e.g., sludge).

14.
Artigo em Inglês | MEDLINE | ID: mdl-39013074

RESUMO

Two-dimensional materials have been extensively studied in field-effect transistors (FETs). However, the performance of p-type FETs has lagged behind that of n-type, which limits the development of complementary logical circuits. Here, we investigate the electronic properties and transport performance of anisotropic monolayer GaSCl for p-type FETs through first-principles calculations. The anisotropic electronic properties of monolayer GaSCl result in excellent device performance. The p-type GaSCl FETs with 10 nm channel length have an on-state current of 2351 µA/µm for high-performance (HP) devices along the y direction and an on-state current of 992 µA/µm with an on/off ratio exceeding 107 for low-power (LP) applications along the x direction. In addition, the delay-time (τ) and power dissipation product of GaSCl FETs can fully meet the International Technology Roadmap for Semiconductors standards for HP and LP applications. Our work illustrates that monolayer GaSCl is a competitive p-type channel for next-generation devices.

15.
Environ Res ; 260: 119604, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002636

RESUMO

Fluoride pollution and water scarcity are urgent issues. Reducing fluoride concentration in water is crucial. Kaolinite has been used to study adsorption and fluoride removal in water and to characterize material properties. The experimental results showed that the adsorption capacity of kaolinite decreased with increasing pH. The highest adsorption of fluoride occurred at pH 2, with a capacity of 11.1 mg/g. The fluoride removal efficiency remained high after four regeneration cycles. The fitting results with the Freundlich isotherm model and the external diffusion model showed that the non-homogeneous adsorption of kaolinite fit the adsorption behavior better. Finally, the adsorption mechanism was analyzed by FT-IR and XPS. The binding energies of various adsorption sites and the chemical adsorption properties of atomic states were discussed in relation to DFT calculations. The results showed that Al and H sites were the main binding sites, and the bonding stability for different forms of fluoride varies, with the size of Al-F (-7.498 eV) > H-F (-6.04 eV) > H-HF (-3.439 eV) > Al-HF (-3.283 eV). Furthermore, the density of states and Mulliken charge distribution revealed that the 2p orbital of F was found to be active in the adsorption process and was the main orbital for charge transfer.

16.
Sci Rep ; 14(1): 16293, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009787

RESUMO

In the present work, we report on theoretical studies of thermodynamic properties, structural and dynamic stabilities, dependence of unit-cell parameters and elastic constants upon hydrostatic pressure, charge carrier effective masses, electronic and optical properties, contributions of interband transitions in the Brillouin zone of the novel Tl2HgGeSe4 crystal. The theoretical calculations within the framework of the density-functional perturbation theory (DFPT) are carried out employing different approaches to gain the best correspondence to the experimental data. The present theoretical data indicate the dynamical stability of the title crystal and they reveal that, under hydrostatic pressure, it is much more compressible along the a-axis than along the c-axis. Strikingly, the charge effective mass values ( m e ∗ and m h ∗ ) vary considerably when the high symmetry direction changes indicating a relative anisotropy of the charge-carrier's mobility. Furthermore, the Young modulus and compressibility are characterized by the maximum and minimum values ( E max and E min ) and ( ß max and ß min ) that are equal to (62.032 and 28.812) GPa and (13.672 and 6.7175) TPa-1, respectively. Additionally, we have performed calculations of the Raman spectra (RS) and reached a good correspondence with the experimental RS spectra of the Tl2HgGeSe4 crystal. The XPES associated to RS constitutes powerful techniques to explore the oxidized states of Se and Ge in Tl2HgGeSe4 system.

17.
Sensors (Basel) ; 24(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39000875

RESUMO

It is worthwhile to calculate the execution cost of a manipulator for selecting a planning algorithm to generate trajectories, especially for an agricultural robot. Although there are various off-the-shelf trajectory planning methods, such as pursuing the shortest stroke or the smallest time cost, they often do not consider factors synthetically. This paper uses the state-of-the-art Python version of the Robotics Toolbox for manipulator trajectory planning instead of the traditional D-H method. We propose a cost function with mass, iteration, and residual to assess the effort of a manipulator. We realized three inverse kinematics methods (NR, GN, and LM with variants) and verified our cost function's feasibility and effectiveness. Furthermore, we compared it with state-of-the-art methods such as Double A* and MoveIt. Results show that our method is valid and stable. Moreover, we applied LM (Chan λ = 0.1) in mobile operation on our agricultural robot platform.

18.
Sensors (Basel) ; 24(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000995

RESUMO

A reliable and efficient rail track defect detection system is essential for maintaining rail track integrity and avoiding safety hazards and financial losses. Eddy current (EC) testing is a non-destructive technique that can be employed for this purpose. The trade-off between spatial resolution and lift-off should be carefully considered in practical applications to distinguish closely spaced cracks such as those caused by rolling contact fatigue (RCF). A multi-channel eddy current sensor array has been developed to detect defects on rails. Based on the sensor scanning data, defect reconstruction along the rails is achieved using an inverse algorithm that includes both direct and iterative approaches. In experimental evaluations, the EC system with the developed sensor is used to measure defects on a standard test piece of rail with a probe lift-off of 4-6 mm. The reconstruction results clearly reveal cracks at various depths and spacings on the test piece.

19.
Sensors (Basel) ; 24(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39001047

RESUMO

The Broad Learning System (BLS) has demonstrated strong performance across a variety of problems. However, BLS based on the Minimum Mean Square Error (MMSE) criterion is highly sensitive to label noise. To enhance the robustness of BLS in environments with label noise, a function called Logarithm Kernel (LK) is designed to reweight the samples for outputting weights during the training of BLS in order to construct a Logarithm Kernel-based BLS (L-BLS) in this paper. Additionally, for image databases with numerous features, a Mixture Autoencoder (MAE) is designed to construct more representative feature nodes of BLS in complex label noise environments. For the MAE, two corresponding versions of BLS, MAEBLS, and L-MAEBLS were also developed. The extensive experiments validate the robustness and effectiveness of the proposed L-BLS, and MAE can provide more representative feature nodes for the corresponding version of BLS.

20.
J Hazard Mater ; 476: 135082, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39003810

RESUMO

Iron oxide minerals control the environmental behavior of trace elements. However, the potential effects of electron transfer directions by iron oxides between organic acids and trace elements remain unclear. This study investigates the redox capacity of tartaric acid (TA) with chromate (Cr(Ⅵ)) or arsenate (As(V)) on lepidocrocite (Lep) from the perspective of electron transfer. The results demonstrated the configurations of TA (bidentate binuclear (BB)), As(V) (BB), and Cr(Ⅵ) (BB and protonated monodentate binuclear (HMB)) on Lep. Frontier molecular orbital calculations and X-ray photoelectron spectroscopy (XPS) binding energy shifts further indicated different electron transfer directions between TA and the oxyanions on Lep. The iron of Lep might act as electron acceptors when TA is adsorbed, whereas the iron and oxygen of Lep act as electron donors when As(V) is adsorbed. The iron of Lep might accept electrons from its oxygen and subsequently transfer these electrons to Cr(Ⅵ). Macroscopic validation experiments showed the reduction of Cr(VI), whereas no reduction of As(V). The XPS analysis showed a peak shift, with the possible formation of As-Fe-TA ternary complexes and electron transfer on Lep. These findings indicate that mineral interfacial electron transfer considerably influences the transport and transformation of oxyanions.

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