To assess whether CT-based radiomics of the ablation zone (AZ) can predict local tumour progression (LTP) after thermal ablation for colorectal liver metastases (CRLM).
Eighty-two patients with 127 ...CRLM were included. Radiomics features (with different filters) were extracted from the AZ and a 10 mm periablational rim (PAR)on portal-venous-phase CT up to 8 weeks after ablation. Multivariable stepwise Cox regression analyses were used to predict LTP based on clinical and radiomics features. Performance (concordance c-statistics) of the different models was compared and performance in an ‘independent’ dataset was approximated with bootstrapped leave-one-out-cross-validation (LOOCV).
Thirty-three lesions (26 %) developed LTP. Median follow-up was 21 months (range 6−115).
The combined model, a combination of clinical and radiomics features, included chemotherapy (HR 0.50, p = 0.024), cT-stage (HR 10.13, p = 0.016), lesion size (HR 1.11, p = <0.001), AZ_Skewness (HR 1.58, p = 0.016), AZ_Uniformity (HR 0.45, p = 0.002), PAR_Mean (HR 0.52, p = 0.008), PAR_Skewness (HR 1.67, p = 0.019) and PAR_Uniformity (HR 3.35, p < 0.001) as relevant predictors for LTP. The predictive performance of the combined model (after LOOCV) yielded a c-statistic of 0.78 (95 %CI 0.65−0.87), compared to the clinical or radiomics models only (c-statistic 0.74 (95 %CI 0.58−0.84) and 0.65 (95 %CI 0.52−0.83), respectively).
Combining radiomics features with clinical features yielded a better performing prediction of LTP than radiomics only. CT-based radiomics of the AZ and PAR may have potential to aid in the prediction of LTP during follow-up in patients with CRLM.
The present study aimed to explore the behavior of unpolarized fragmentation functions (FFs) of pion in the regions of small momentum fractions
z
. This study used a novel phenomenological QCD ...approach in the framework of fractal (or self-similar) behavior of FFs to quantify the small-
z
region. To this end, a simple parameterization for the pion fractal FFs is considered and small
z
experimental datasets on single inclusive pion production in electron–positron (
e
+
e
-
) annihilation (SIA) for the range of
10.54
<
Q
<
91.28
GeV and
z
<
0.1
are included in this analysis. The estimations of the uncertainty in the present analysis are carried out using the standard “Hessian” approach. In total, considering the overall value of
χ
2
/
dof
and theory/data comparisons, the results indicate excellent agreements between the experimental datasets and the theory predictions at small momentum fractions
z
. Finally, we present detailed comparisons between predictions for the relevant small-
z
observables obtained with various recent models of pion FFs available in literature. Considering the findings presented in this study, we discuss how our knowledge of pion FFs may be improved at small-
z
by future measurements.
•A dynamic model for cable driven parallel robots is proposed.•The model includes position and tension dependent properties of the manipulator.•The model has been validated comparing experimental and ...numerical responses.•The response is characterized by structural and cable-induced modes.
In this paper we propose a modeling strategy for Cable Driven Parallel Robots (CDPRs) that - given their complexity - are typically addressed using simplified analysis, therefore neglecting relevant dynamics. Specifically, the finite element method is used for cables modeling, in order to account for their mass and stress-dependent stiffness. Geometrical effects given by platform motion in the 3D space have been included in our study, coupling cables finite element model and platform dynamic, also mimicking the wrapping of cords around winches. As a result, frequency and time domain responses under harmonic excitation are well captured and, in contrast with other works, the modal analysis revealed system vibrations characterized by local and global modes.
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► Modification of magnetite nanoparticles with aminopropyl groups gave APTSCMNPs. ► Reaction of APTSCMNPs with polyoxometalates afforded new hybrid nanomaterials. ► The prepared ...hybrid nanomaterials showed superparamagnetic properties.
Magnetite–polyoxometalate hybrid nanomaterials were prepared by surface modification of magnetite nanoparticles with polyoxometalates. Silica coating of magnetite nanoparticles with tetraethyl orthosilicate and then functionalization with aminopropyl trimethoxy silane (APTS) yielded aminopropyl modified silica coated magnetite nanoparticles (APTSCMNPs). Reaction of the resulted nanoparticles with H3PMo12O40 and H3PW12O40 heteropoly acids produced hybrid nanomaterials, PMo-APTSCMNPs and PW-APTSCMNPs, respectively. The resulted nanomaterials were characterized with different physicochemical techniques such as Fourier transform infrared (FT-IR) and atomic absorption spectroscopies, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), and thermogravimetric analyzes (TGA and DTA). VSM analysis showed superparamagnetic properties of the materials and TEM and SEM analyses indicated the relatively uniform spherical nanoparticles with 20nm average size.
Continuous, non-intrusive measurements of time-varying viscosity of Pseudomonas sp. biofilms are made using a microfluidic method that combines video tracking with a semi-empirical viscous flow ...model. The approach uses measured velocity and height of tracked biofilm segments, which move under the constant laminar flow of a nutrient solution. Following a low viscosity growth stage, rapid thickening was observed. During this stage, viscosity increased by over an order of magnitude in less than ten hours. The technique was also demonstrated as a promising platform for parallel experiments by subjecting multiple biofilm-laden microchannels to nutrient solutions containing NaCl in the range of 0 to 34 mM. Preliminary data suggest a strong relationship between ionic strength and biofilm properties, such as average viscosity and rapid thickening onset time. The technique opens the way for a combinatorial approach to study the response of biofilm viscosity under well-controlled physical, chemical and biological growth conditions.
Human serum albumin (HSA) is a soluble blood protein which binds to small molecules (such as drugs and toxins) and transfers them within the blood circulation. In this research, the interaction of ...diazinon, as a toxic organophosphate, with HSA was investigated. Various biophysical methods such as fluorescence, ultraviolet–visible (UV-vis), Fourier transform infrared spectroscopy, and molecular docking were utilized to characterize the binding properties of diazinon to HSA under physiological-like condition. The UV-vis spectroscopy showed that the absorption increased and the fluorescence intensity of HSA decreased regularly with regard to the gradual increases of the concentrations of diazinon. Due to the binding constant of (k
a = 3.367 × 10+4 M−1), the α-helix structure for the first day and 35 days of incubation were obtained 66.09–55.4% and 59.99–46.48%, respectively, and their amounts in other secondary structures (β-sheet, β-anti, and random (r) coils) were increased. The molecular docking revealed a good binding site in HSA (Trp-214) for diazinon which was related to the considerable alterations in HSA secondary and tertiary structures. There is a close relationship between the secondary structure of protein and its biological activity and after 35 days of incubation, the high toxic concentrations of diazinon can make HSA to be partially unfolded and lose its structure.
A design methodology for multioctave RF power amplifiers (PAs) is presented in this brief using sequential harmonic characterization. The investigation of in-band harmonics on the multioctave ...performance of the RF PA shows that a more optimal performance can be achieved using the proposed technique compared to the conventional load-pull. To demonstrate the capability of this technique, a broadband multioctave PA prototype was designed and fabricated using sequential second harmonic characterization. The fabricated prototype uses a GaN HEMT from Cree Inc. and exhibits a drain efficiency of 53%-64% in the range of 0.7-4.0 GHz while having an output power of 37.5-39.1 dBm corresponding to the fractional bandwidth of 140%. Measurement results validate the proposed method as a robust PA design procedure for broadband and multistandard applications.
Dielectrophoresis is the electro‐mechanical phenomenon where a force is generated on a dielectric material when exposed to a non‐uniform electric field. It has potential to be exploited in smart ...materials for robotic manipulation and locomotion, but to date it has been sparsely studied in this area. Herein, a new type of dielectrophoretic actuator exploiting a novel electroactive polymer is described, termed as dielectrophoretic elastomer (DPE), which undergoes electric field‐driven actuation through dielectrophoresis. Unique deflection and morphing behavior of the elastomer induced by controlling the dielectrophoretic phenomenon, such as out‐of‐plane deformation and independence of electric field polarity, are illustrated. The dielectric and mechanical properties of the DPE are studied to gain insight into the influence of materials composition on deformation. Actuation performance using different electrode parameters is experimentally investigated with supplementary analysis through finite element simulation, revealing the relationship between electric field inhomogeneity and deflection. The applications of DPE actuators in a range of robotic devices is demonstrated, including a pump, an adjustable optical lens, and a walking robot. This diverse range of applications illustrates the wide potential of these new soft‐and‐smart electric field‐driven materials for use in soft robotics and soft compliant devices.
A new class of electroactive material is introduced, termed as dielectrophoretic elastomer, which is the first‐ever demonstrated active morphing and moving matter that is driven by inhomogeneities in the electric field. Its potential for applications in pumps, optical lenses, and walking robots, providing new solutions for the design of soft and compliant devices, is explored.
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