Enhanced SWAT calibration through intelligent range-based parameter optimization.

Hydrological models are vital tools in environmental management. Weaknesses in model robustness for hydrological parameters transfer uncertainties to the model outputs. For streamflow, the optimized parameters are the primary source of uncertainty. A reliable calibration approach that reduces prediction uncertainty in model simulations is crucial for enhancing model robustness and reliability. The optimization of parameter ranges is a key aspect of parameter calibration, yet there is a lack of literature addressing the optimization of parameter ranges in hydrological models. In this paper, we introduce a parameter calibration strategy that applies a clustering technique, specifically the Self-Organizing Map (SM), to intelligently navigate the parameter space during the calibration of the Soil and Water Assessment Tool (SWAT) model for monthly streamflow simulation in the Baishan Basin, Jilin Province, China. We selected the representative algorithm, the Sequential Uncertainty Fitting version 2 (SUFI-2), from the commonly used SWAT Calibration and Uncertainty Programs for comparison. We developed three schemes: SUFI-2, SUFI-2-Narrowing Down (SUFI-2-ND), and SM. Multiple diagnostic error metrics were used to compare simulation accuracy and prediction uncertainty. Among all schemes, SM outperformed the others in describing watershed streamflow, particularly excelling in the simulation of spring snowmelt runoff (baseflow period). Additionally, the prediction uncertainty was effectively controlled, demonstrating the SM's adaptability and reliability in the interval optimization process. This provides managers with more credible prediction results, highlighting its potential as a valuable calibration tool in hydrological modeling.

Thermogravimetric experiments based prediction of biomass pyrolysis behavior: A comparison of typical machine learning regression models in Scikit-learn.

A variety of machine learning (ML) models have been extensively utilized in predicting biomass pyrolysis owing to their prowess in deciphering complex non-linear relationships between inputs and outputs, but there is still a lack of consensus on the optimal methods. This study elaborates on the development, optimization, and evaluation of three ML methodologies, namely, artificial neural networks, random forest (RF), and support vector machines, aimed to determine the optimal model for accurate prediction of biomass pyrolysis behavior using thermogravimetric data. This work assesses the utility of thermal data derived from these models in the computation of kinetic and thermodynamic parameters, alongside an analysis of their statistical performance. Eventually, the RF model exhibits superior physical interpretability and the least discrepancy in predicting kinetic and thermodynamic parameters. Furthermore, a feature importance analysis conducted within the RF model framework quantitatively reveals that temperature and heating rate account for 98.5 % and 1.5 %, respectively.

Kinetic reaction mechanism of lignocellulosic biomass oxidative pyrolysis based on combined kinetics.

The kinetics knowledge of lignocellulosic biomass decomposition is essential to develop efficient thermochemical conversion technology. However, the simplification of reaction mechanisms in existing oxidative pyrolysis studies largely compromises the application of kinetic models. To explore more exact kinetic parameters and reaction mechanism of lignocellulosic biomass oxidative pyrolysis, an updated oxidative pyrolysis kinetic model (seven-step reaction combined kinetics model) coupled with an optimization algorithm is proposed. Based on a series of thermogravimetric experiments in an air atmosphere, the extra oxidative pyrolysis kinetic parameters are obtained by the Shuffled Complex Evolution method. The proposed kinetic model is validated based on the degradation process of each component (hemicellulose, cellulose, and lignin). Furthermore, the obtained kinetic parameters are applied to predict the oxidative pyrolysis behavior, and the predicted mass loss rate is in good agreement with the experimental data. Eventually, according to the key combined kinetics parameters, it is found that the oxidative pyrolysis mechanisms of hemicellulose, cellulose, and lignin correspond to the power law, nucleation & growth, and chemical reaction order, respectively, while the combustion of char corresponds to the reaction order mechanism.

Synthesis of Cu2O Nanostructures with Tunable Crystal Facets for Electrochemical CO2 Reduction to Alcohols.

Electrochemical CO2 reduction enables the conversion of intermittent renewable energy to value-added chemicals and fuel, presenting a promising strategy to relieve CO2 emission and achieve clean energy storage. In this work, we developed nanosized Cu2O catalysts using the hydrothermal method for electrochemical CO2 reduction to alcohols. Cu2O nanoparticles (NPs) of various morphologies that were enclosed with different crystal facets, named as Cu2O-c (cubic structure with (100) facets), Cu2O-o (octahedron structure with (111) facets), Cu2O-t (truncated octahedron structure with both (100) and (111) facets), and Cu2O-u (urchin-like structure with (100), (220), and (222) facets), were prepared by regulating the content of a polyvinyl pyrrolidone (PVP) template. The electrochemical CO2 reduction performance of the different Cu2O NPs was evaluated in the CO2-saturated 0.5 M KHCO3 electrolyte. The as-synthesized Cu2O nanostructures were capable of reducing CO2 to produce alcohols including methanol, ethanol, and isopropanol. The alcohol selectivity of the different Cu2O NPs followed the order of Cu2O-t < Cu2O-u < Cu2O-c < Cu2O-o (with the total Faradaic efficiencies of alcohol products of 10.7, 25.0, 26.2, and 35.4%). The facet-dependent effects were associated with the varied concentrations of oxygen-vacancy defects, different energy barriers of CO2 reduction, and distinct Cu-O bond lengths over the different crystal facets. The desired Cu2O-o catalyst exhibited good reduction activity with the highest partial current density of 0.51 mA/cm2 for alcohols. The Faradaic efficiencies of alcohol products were 4.9% for methanol, 17.9% for ethanol, and 12.6% for isopropanol. The good electrochemical CO2 reduction performance was also associated with the surface reconstruction of Cu2O, which endowed the catalyst with abundant Cu0 and Cu+ sites for promoted CO2 activation and stabilized CO* adsorption for enhanced C-C coupling. This work will provide a new route for enhancing the alcohol selectivity of nanostructured Cu2O catalysts by crystal facet engineering.

Percutaneous Transhepatic Papillary Balloon Dilation versus Endoscopic Retrograde Cholangiopancreatography for Common Bile Duct Stones: A Multicenter Prospective Study.

Background Endoscopic retrograde cholangiopancreatography (ERCP) is recommended by major guidelines for the removal of common bile duct (CBD) stones but is technically challenging in patients with low cardiopulmonary reserve and anatomic abnormalities of the upper gastrointestinal (GI) tract. Purpose To compare percutaneous transhepatic papillary balloon dilation (PTPBD) with ERCP for CBD stone removal. Materials and Methods Participants with one to three CBD stones (largest stone ≤30 mm) and without intrahepatic bile duct or gallbladder stones were eligible for this prospective cohort study. PTPBD was recommended in participants with low cardiopulmonary reserve or definitive anatomic abnormalities of the upper GI tract. Otherwise, both procedures were offered without preference. Follow-up, including abdominal CT, was conducted at 1-week and 1-, 3- and 6-month follow-up, and every 6 months thereafter. US and MR cholangiopancreatography were conducted if recurrence could not be confirmed with CT. Technical success rate was the primary outcome. Results A total of 531 participants were analyzed: there were 360 undergoing PTPBD (median age, 76 years; interquartile range [IQR], 64-82 years; 163 men) and 171 undergoing ERCP (median age, 66 years; IQR, 57-74 years; 94 men). The technical success rate was 99% (355 of 360) in the PTPBD group and 98% (167 of 171) in the ERCP group (relative risk, 1.02; P = .12). The incidence of overall complications was 4% (13 of 360) for PTPBD and 8% (13 of 171) for ERCP (relative risk, 0.27; 95% CI: 0.12, 0.61; P < .001). The PTPBD group showed a longer fluoroscopy time and a higher radiation exposure, with adjusted differences of 28.7 minutes (95% CI: 22.2, 35.2) and 384.3 mGy (95% CI: 296.5, 472), respectively. A propensity score-matching analysis (n = 123 per group) indicated that PTPBD had a slightly higher technical success rate and significantly fewer complications. Conclusion When compared with endoscopic retrograde cholangiopancreatography, percutaneous transhepatic papillary balloon dilation has a similar technical success rate and fewer perioperative complications but a higher radiation exposure. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by van Sonnenberg and Mueller in this issue.

A novel injury site-natural antibody targeted complement inhibitor protects against lung transplant injury.

Complement is known to play a role in ischemia and reperfusion injury (IRI). A general paradigm is that complement is activated by self-reactive natural IgM antibodies (nAbs), after they engage postischemic neoepitopes. However, a role for nAbs in lung transplantation (LTx) has not been explored. Using mouse models of LTx, we investigated the role of two postischemic neoepitopes, modified annexin IV (B4) and a subset of phospholipids (C2), in LTx. Antibody deficient Rag1-/- recipient mice were protected from LTx IRI. Reconstitution with either B4 or C2nAb restored IRI, with C2 significantly more effective than B4 nAb. Based on these information, we developed/characterized a novel complement inhibitor composed of single-chain antibody (scFv) derived from the C2 nAb linked to Crry (C2scFv-Crry), a murine inhibitor of C3 activation. Using an allogeneic LTx, in which recipients contain a full nAb repertoire, C2scFv-Crry targeted to the LTx, inhibited IRI, and delayed acute rejection. Finally, we demonstrate the expression of the C2 neoepitope in human donor lungs, highlighting the translational potential of this approach.

FBXW5 acts as a negative regulator of pathological cardiac hypertrophy by decreasing the TAK1 signaling to pro-hypertrophic members of the MAPK signaling pathway.

Pathological cardiac hypertrophy is a crucial cause of cardiac morbidity and mortality worldwide. However, the molecular mechanisms of this disease remain incompletely understood. As a member of E3 ubiquitin ligases, F-box/WD repeat-containing protein 5 (FBXW5) has been implicated in various pathophysiological processes. However, the role of FBXW5 in pathological cardiac hypertrophy remains largely unknown. In this study, decreased expression of FBXW5 was observed in both neonatal rat cardiomyocytes and mouse hearts with hypertrophic remodeling. Gain- and loss-of-function experiments were performed to study the potential function of FBXW5 in pathological cardiac hypertrophy. The in vitro results showed that FBXW5 had a protective effect against cardiac hypertrophy induced by phenylephrine (PE). FBXW5 knockout mice and mice with AAV9-mediated FBXW5 overexpression were generated. Consistent with the in vitro results, FBXW5 deficiency aggravated cardiac hypertrophy induced by pressure overload. FBXW5 overexpression protected mice from hypertrophic stimuli. Remarkably, FBXW5 ameliorated pathological cardiac hypertrophy by directly interacting with the protein transforming growth factor-beta-activated kinase 1 (TAK1) and blocking the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, inhibition of TAK1 prevented the effects of FBXW5 on agonist- or pressure overload-induced cardiac hypertrophy. These findings imply that FBXW5 is an essential negative regulator and may be a potential therapeutic target for pathological cardiac hypertrophy.

Experimental study of the effect of internal pressure on oscillating behavior of pool fires.

A series of experiments have been conducted to study the flame behavior of ethanol pool fires in a closed chamber. The effect of internal pressure and the size of the pool burner is considered. Tests include pressure conditions ranging from 50 kPa to 350 kPa and 5 circular pool burners with different diameters (2 cm, 4 cm, 6 cm, 8 cm, and 10 cm). Measurements such as gas temperature, internal pressure, oxygen concentration, and video record for all tests are obtained. Steady-state burning period is identified to facilitate a quantitative analysis of flame behavior. Image processing is carried out to obtain time average appearance of pool fires. The concept of oscillation intensity is introduced. Oscillation behaviors of pool fires in a closed system as a function of internal pressure and pan diameter are correlated with oscillation intensity. Four flame structures are observed: laminar, tip flicking, sinuous meandering, and turbulent flame. Relationships between oscillation intensity to flame structure and Grashof number to flame structure are established. Effect of internal pressure and gravitational force to oscillation frequency is also accessed. Simple theoretical model is developed. An empirical expression using the relationship of Strouhal number and Grashof number is established. Two distinct behaviors on oscillation frequency as a function of pressure are observed. Results obtained from this work will facilitate the understanding of oscillation behavior of ethanol pool fires in different sizes with various internal pressure conditions in a closed chamber.

Effect of pressure on the heat transfer of pool fire in a closed chamber.

A combined experimental and analytical study was performed to determine the effect of pressure on the heat transfer of pool fire in a closed chamber. A series of ethanol pool fires with nominal diameters from 4 cm to 10 cm were conducted for a wide range of pressure conditions in between ~ 60 kPa to 250 kPa. Considering the effect of pressure, a theoretical formulation was proposed to estimate the radiation flux received by the pool surface from the chamber wall and hot gases. The relationship between the modified mass burning flux of pool fire and pressure was obtained. It was found that external radiation heat transfer received by pool surface depends significantly on gas temperature and its radiative properties and wall temperature. Results showed that these parameters are highly coupled in determining the effect of pressure to the external radiation. Furthermore, the average mass burning flux modified by the obtained external radiation was fitted with pressure by a power function and the fitted exponent value was consistent with theoretical analysis.

Microtopography-Guided Radial Gradient Circle Array Film with Nanoscale Resolution.

Distribution of multimaterials at arbitrary positions with nanoscale resolution and over a large area substrate is essential to future advances in functional graded materials. Such stringent requirements are highly beyond the reach of current techniques, although newly developed 3D printing technologies are addressed. Here, a radial gradient circle array film with the distribution accuracy up to ≈18 nm is fabricated by using microtopographic substrate. A mathematical model is developed to guide the distribution of position, size, shape, and type of materials on an arbitrary section for the given morphology of substrate. The periodic electrical and mechanical properties of the radial gradient circle film are identified, which can be beneficial for further functionalization and applications, such as gradient refractive index lenses, microcoils, and microantennas.

Multimaterial 3D Printing for Arbitrary Distribution with Nanoscale Resolution.

At the core of additive manufacturing (3D printing) is the ability to rapidly print with multiple materials for arbitrary distribution with high resolution, which can remove challenges and limits of traditional assembly and enable us to make increasingly complex objects, especially exciting meta-materials. Here we demonstrate a simple and effective strategy to achieve nano-resolution printing of multiple materials for arbitrary distribution via layer-by-layer deposition on a special deposition surface. The established physical model reveals that complex distribution on a section can be achieved by vertical deformation of simple lamination of multiple materials. The deformation is controlled by a special surface of the mold and a contour-by-contour (instead of point-by-point) printing mode is revealed in the actual process. A large-scale concentric ring array with a minimum feature size below 50 nm is printed within less than two hours, verifying the capacity of high-throughput, high-resolution and rapidity of printing. The proposed printing method opens the way towards the programming of internal compositions of object (such as functional microdevices with multiple materials).

Efficacy and Safety of a Novel Catheter for Transradial Cerebral Angiography.

BACKGROUND: The goal of this study is to evaluate the safety and efficacy of a novel catheter for right radial artery approach cerebral angiography. METHODS: Patients from the Neurology Department of The Second Affiliated Hospital of Guangxi Traditional Chinese Medical University who underwent diagnostic cerebral angiography of either the left vertebral artery dominant type or balanced type were enrolled in this study. RESULTS: A total of 167 patients were treated between February 2016 and December 2017, of whom 44 were excluded based on study exclusion criteria and 123 were enrolled in the present analysis. Bilateral subclavian artery catheterization and bilateral common carotid artery catheterization were conducted successfully in all 123 patients. The success rate of selective catheterization of the left vertebral artery was 87.8% (108/123). The success rate of selective catheterization of the right vertebral artery using the novel catheter was 89.0% (73/82). The average fluoroscopy time was 6.5 ± 3.4 min, the average operation duration was 47 ± 3.7 (range 50-90) min, and the average dosage of contrast agent was 112.3 ± 8.1 mL. One patient exhibited an absence of pulse in the punctual radial artery after the removal of the arterial compression band, but there was no evidence of ischemia of the distal hand. One patient who was undergoing dual anti-platelet drug treatment suffered from bleeding at the puncture point when deflated for 2 hr after operation; this patient was re-pressurized and re-timed. CONCLUSIONS: This novel catheter improved the success rate of selective left vertebral artery catheterization, and allowed for simplification of the relevant surgical steps. The controllability of this novel catheter was satisfactory, and its associated surgical risk was found to be low.

A facile one-pot preparation of Bi2O2CO3/g-C3N4 composites with enhanced photocatalytic activity.

Bi2O2CO3 modified graphitic carbon nitride (g-C3N4) nanosheets were prepared by a simple one-pot synthetic strategy. In the presence of ammonium nitrate, different mass ratios of bismuth nitrate/melamine were used to fabricate these catalysts, which were characterized by X-ray diffraction (XRD), N2-physisorption, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis analysis, and photoluminescence (PL). The catalytic properties of composites were evaluated by photodegrading tetracycline hydrochloride (TC) under visible light irradiation. Among these catalysts, Bi2O2CO3(1.5)/g-C3N4 showed the highest catalytic activity, which was more than 16 times greater than the pristine g-C3N4 material. The improved photocatalytic properties of Bi2O2CO3/g-C3N4 may be due to the formation of a heterojunction between Bi2O2CO3 and g-C3N4, leading to the effective separation of photo-induced carriers and the enhanced absorption of visible light. Furthermore, the Bi2O2CO3/g-C3N4 composites had considerable catalytic stability, which was a key element for their potential applications.

Emphysema-associated Autoreactive Antibodies Exacerbate Post-Lung Transplant Ischemia-Reperfusion Injury.

Chronic obstructive pulmonary disease-associated chronic inflammation has been shown to lead to an autoimmune phenotype characterized in part by the presence of lung autoreactive antibodies. We hypothesized that ischemia-reperfusion injury (IRI) liberates epitopes that would facilitate preexisting autoantibody binding, thereby exacerbating lung injury after transplant. We induced emphysema in C57BL/6 mice through 6 months of cigarette smoke (CS) exposure. Mice with CS exposure had significantly elevated serum autoantibodies compared with non-smoke-exposed age-matched (NS) mice. To determine the impact of a full preexisting autoantibody repertoire on IRI, we transplanted BALB/c donor lungs into NS or CS recipients and analyzed grafts 48 hours after transplant. CS recipients had significantly increased lung injury and immune cell infiltration after transplant. Immunofluorescence staining revealed increased IgM, IgG, and C3d deposition in CS recipients. To exclude confounding alloreactivity and confirm the role of preexisting autoantibodies in IRI, syngeneic Rag1-/- (recombination-activating protein 1-knockout) transplants were performed in which recipients were reconstituted with pooled serum from CS or NS mice. Serum from CS-exposed mice significantly increased IRI compared with control mice, with trends in antibody and C3d deposition similar to those seen in allografts. These data demonstrate that pretransplant CS exposure is associated with increased IgM/IgG autoantibodies, which, upon transplant, bind to the donor lung, activate complement, and exacerbate post-transplant IRI.

A Universal Solution of Controlling the Distribution of Multimaterials during Macroscopic Manipulation via a Microtopography-Guided Substrate.

Any object can be considered as a spatial distribution of atoms and molecules; in this sense, we can manufacture any object as long as the precise distribution of atoms and molecules is achieved. However, the current point-by-point methods to precisely manipulate single atoms and single molecules, such as the scanning tunneling microscope (STM), have difficulty in manipulating a large quantity of materials within an acceptable time. The macroscopic manipulation techniques, such as magnetron sputtering, molecular beam epitaxy, and evaporation, could not precisely control the distribution of materials. Herein, we take a step back and present a universal method of controlling the distribution of multimaterails during macroscopic manipulation via microtopography-guided substrates. For any given target distribution of multimaterials in a plane, the complicated lateral distribution of multimaterials was firstly transformed into a simple spatial lamellar body. Then, a deposition mathematical model was first established based on a mathematical transformation. Meanwhile, the microtopographic substrate can be fabricated according to target distribution based on the deposition mathematical model. Following this, the deposition was implemented on the substrate according to the designed sequence and thickness of each material, resulting in the formation of the deposition body on the substrate. Finally, the actual distribution was obtained on a certain section in the deposition body by removing the upside materials. The actual distribution can mimic the target one with a controllable accuracy. Furthermore, two experiments were performed to validate our method. As a result, we provide a feasible and scalable solution for controlling the distribution of multimaterials, and point out the direction of improving the position accuracy of each material. We may achieve real molecular manufacturing and nano-manufacturing if the position accuracy of distribution approaches the atomic level.

Novel p-n junction UiO-66/BiOI photocatalysts with efficient visible-light-induced photocatalytic activity.

Novel visible-light-induced UiO-66/BiOI photocatalysts with a p-n junction structure have been prepared for the first time through a facile hydrothermal method. The prepared photocatalysts were characterized using the powder X-ray diffraction, high resolution transmission electron microscopy, scanning electron microscopy, UV-visible diffuse reflectance spectra, and N2 adsorption-desorption (Brunauer-Emmett-Teller) techniques respectively. The photodegradation performances of UiO-66/BiOI photocatalysts were evaluated by photodegrading salicylic acid under visible-light irradiation. The UiO-66/BiOI composites displayed much higher photocatalytic efficiencies than pure BiOI under visible light. When the content of UiO-66 was 5.2 wt%, the composite (UiO-66/BiOI-2) has the best photocatalytic activity. Most of the salicylic acid molecules can be degraded in 100 min. The degradation rate of UiO-66/BiOI-2 samples is higher than single BiOI and UiO-66. The enhanced photocatalytic performance of UiO-66/BiOI may be ascribed to the formation of p-n heterojunctions between BiOI and UiO-66, which facilitates the transfer and separation of the photogenerated charge carriers. After recycling of the photocatalyst for five times for the photodegradation of salicylic acid, more than 85% of salicylic acid could still be degraded in the fifth cycle, implying that the as-prepared photocatalysts are highly stable.

Seawater splitting for hydrogen evolution by robust electrocatalysts from secondary M (M = Cr, Fe, Co, Ni, Mo) incorporated Pt.

Water splitting is a promising technique for clean hydrogen energy harvesting. The creation of cost-effective electrocatalysts with improved hydrogen evolution reaction (HER) activity and stability is crucial in realizing persistent hydrogen evolution by reducing the reaction overpotential and minimizing energy consumption. Herein, we present the preparation of alloyed PtM (M = Cr, Fe, Co, Ni, Mo) modified titanium (Ti) mesh by a simple electrodeposition method, aiming at hydrogen generation from seawater splitting. The preliminary results indicate that the Ti/PtM electrodes feature markedly reduced onset overpotentials and Tafel slopes as well as significantly increased exchange current densities compared with pristine Pt electrodes, arising from the incorporation of secondary M atoms into the Pt lattice for alloying effects. Moreover, the competitive dissolution reaction between guest M species to Pt with Cl2 in seawater is beneficial for enhancing the long-term stability of resultant PtM alloy electrodes. The optimized PtMo alloy electrode maintains 91.13% of the initial current density upon 172 h operation in real seawater, making it promising in practical applications.

Regulation of ERK and AKT pathways by hepatitis B virus X protein via the Notch1 pathway in hepatocellular carcinoma.

Hepatitis B virus (HBV) is the dominant risk factor for hepatocellular carcinoma (HCC). HBV X protein (HBx) plays crucial roles in HCC carcinogenesis. HBx interferes with several signaling pathways including the Notch1 pathway in HCC. In this study, we found that Notch1 was highly expressed in HCC, especially in large HCCs. Notch1 and HBx co-localized in HCC and their levels were positively correlated with each other. Notch1 expression was more elevated in HepG2.2.15 cells than that in HepG2 cells. HBx activated the Notch1 pathway in HepG2.2.15 cells. Suppression of HBx and the Notch1 pathway attenuated the growth of HepG2.2.15 cells. Notch1, ERK, and AKT pathways were inhibited after γ-secretase inhibitor treatment. Dual-specificity phosphatase 1 (DUSP1) and phosphatase and tensin homolog (PTEN) were upregulated after γ-secretase inhibitor treatment and Hes1 inhibition. Luciferase reporter assays showed that Hes1 suppressed the promoters of DUSP1 and PTEN genes, which was reversed by γ-secretase inhibitor treatment. Western blotting demonstrated that DUSP1 dephosphorylated pERK and PTEN dephosphorylated pAKT. Collectively, we found a link among HBx, the Notch1 pathway, DUSP1/PTEN, and ERK/AKT pathways, which influenced HCC cell survival and could be a therapeutic target for HCC treatment.

Classification of multi-class motor imagery with a novel hierarchical SVM algorithm for brain-computer interfaces.

Pattern classification algorithm is the crucial step in developing brain-computer interface (BCI) applications. In this paper, a hierarchical support vector machine (HSVM) algorithm is proposed to address an EEG-based four-class motor imagery classification task. Wavelet packet transform is employed to decompose raw EEG signals. Thereafter, EEG signals with effective frequency sub-bands are grouped and reconstructed. EEG feature vectors are extracted from the reconstructed EEG signals with one versus the rest common spatial patterns (OVR-CSP) and one versus one common spatial patterns (OVO-CSP). Then, a two-layer HSVM algorithm is designed for the classification of these EEG feature vectors, where "OVO" classifiers are used in the first layer and "OVR" in the second layer. A public dataset (BCI Competition IV-II-a)is employed to validate the proposed method. Fivefold cross-validation results demonstrate that the average accuracy of classification in the first layer and the second layer is 67.5 ± 17.7% and 60.3 ± 14.7%, respectively. The average accuracy of the classification is 64.4 ± 16.7% overall. These results show that the proposed method is effective for four-class motor imagery classification.

Infrahepatic inferior vena cava clamping with Pringle maneuvers for laparoscopic extracapsular enucleation of giant liver hemangiomas.

BACKGROUND: This study aimed to determine the feasibility of the extracapsular enucleation method for giant liver hemangiomas by infrahepatic inferior vena cava (IVC) clamping and the Pringle maneuver to control intraoperative bleeding under laparoscopic hepatectomy. METHODS: From January 2012 to January 2016, 36 patients underwent laparoscopic extracapsular enucleation of giant liver hemangiomas. Patients were divided into two groups: infrahepatic IVC clamping + Pringle maneuvers group (IVCP group, n = 15) and the Pringle maneuvers group (Pringle group, n = 21). Operative parameters, postoperative laboratory tests, and morbidity and mortality were analyzed. RESULTS: The mean size of liver hemangiomas was 13.3 cm (range 10-25 cm). Infrahepatic IVC clamping + the Pringle maneuvers with laparoscopic extracapsular enucleation significantly reduced intraoperative blood loss (586.7 vs 315.3 mL, p < 0.001) and transfusion rates (23.8 vs 6.7%, p = 0.001), compared with the Pringle maneuver alone. The gallbladder was retained in both groups. The mean arterial pressure (MAP) in Pringle group remained virtually stable before and after clamping of hepatic portal, while it was significantly decreased after IVC clamping in IVCP group than that pre-clamping (p < 0.001). The heart rate of all patients was significantly increased after clamping when compared to pre-clamping heart rates (p < 0.001). Once vascular occlusion was released, MAP returned to normal levels within a few minutes. There were no significant differences in postoperative complications between two groups. The vascular occlusion techniques in both groups had no serious effect on postoperative of hepatic and renal function. CONCLUSIONS: Extracapsular enucleation with infrahepatic IVC clamping + the Pringle maneuver is a safe and effective surgical treatment to control bleeding for giant liver hemangiomas in laparoscopic hepatectomy.