Mechanical activation-enhanced metal-organic coordination strategy to fabricate high-performance starch/polyvinyl alcohol films by extrusion blowing.

The production of high-performance starch-based packaging films by extrusion blowing is challenging, ascribed to poor processability of the blend precursors. In this study, a new strategy of mechanical activation (MA)-enhanced metal-organic coordination was proposed to improve the processability of starch (St)/polyvinyl alcohol (PVA) blend precursor, with calcium acetate (CA) as a chelating agent and glycerol as a plasticizer. MA pretreatment activated the hydroxyl groups of starch and PVA for constructing strong metal-organic coordination between CA and St/PVA during reactive extrusion, which effectively enhanced the melt processing properties of the blend precursor, contributing to the fabrication of high-performance St/PVA films by the extrusion-blowing method. The as-prepared St/PVA films exhibited excellent mechanical properties (tensile strength of 34.5 MPa; elongation at break of 271.8 %), water vapor barrier performance (water vapor permeability of 0.704 × 10-12 g·cm-1·s-1·Pa-1), and oxygen barrier performance (oxygen transmission rate of 0.7 cm3/(m2·day·bar)), along with high transmittance and good uniformity. These outstanding characteristics and performances can be attributed to the improved interfacial interaction and compatibility between the two matrix phases. This study uncovers the mechanism of MA-enhanced metal-organic coordination for improving the properties of starch-based films, which provides a convenient and eco-friendly technology for the preparation of high-performance biodegradable films.

KLK10/LIPH/PARD6B/SLC52A3 are promising molecular biomarkers for the prognosis of pancreatic cancer through a ceRNA network.

Pancreatic adenocarcinoma (PAAD) remains challenging to diagnose and treat clinically due to its difficult early diagnosis, low surgical resection rate, and high risk of postoperative recurrence and metastasis. SMAD4 is a classical mutated gene in pancreatic cancer and is lost in up to 60%-90 % of PAAD patients, and its mutation often predicts a poor prognosis and treatment resistance. In this study, based on the expression profile data in The Cancer Genome Atlas database, we identified a ceRNA network composed of 2 lncRNAs, 1 miRNA, and 4 mRNAs through differential expression analysis and survival prognosis analysis. Among them, high expression of KLK10/LIPH/PARD6B/SLC52A3 influenced the prognosis and overall survival of PAAD patients. We confirmed the high expression of these target genes in pancreatic tissue of pancreatic-specific SMAD4-deficient mice. In addition, immune infiltration analysis showed that the high expression of these target genes affects the tumor immune environment and contributes to the progression of PAAD. Abnormal overexpression of these target genes may be caused by hypermethylation. In conclusion, we found that KLK10/LIPH/PARD6B/SLC52A3 is a potential prognostic marker for PAAD based on a competing endogenous RNA-mediated mechanism and revealed the potential pathogenic mechanism by which deficient expression of SMAD4 promotes pancreatic cancer progression, which provides a new pathway and theoretical basis for targeted therapy or improved prognosis of pancreatic cancer. These data will help reveal potential therapeutic targets for pancreatic cancer and improve the prognosis of pancreatic cancer patients.

Fabrication of a poly(N-isopropylacrylamide)-grafted alginate composite aerogel for efficient treatment of emulsified oily wastewater.

The treatment of emulsion wastewater poses significant challenges. In this study, a novel porous material, namely esterified bagasse/poly(N, N-dimethylacrylamide)/sodium alginate (SBS/PDMAA/Alg) aerogel, was developed for efficient demulsification and oil recovery. By grafting a poly(N-isopropylacrylamide) (PNIPAM) brush onto the SBS/PDMAA/Alg skeleton through free radical polymerization, the resulting aerogel exhibits both surface charge and a molecular brush structure. The aerogel demonstrates remarkable demulsification efficiency for cationic surfactant-stabilized emulsions at various concentrations, achieving a demulsification efficiency of 95.6% even at an oil content of 100 g L-1. Furthermore, the molecular brush structure extends the application range of the aerogel, enabling a demulsification efficiency of 98.3% for anionic and non-ionic surfactant-stabilized emulsions. The interpenetrating polymer network (IPN) structure formed by SBS, PDMAA, and alginate enhances the mechanical stability of the aerogel, enabling a demulsification efficiency of 91.3% even after 20 repeated cycles. The demulsification ability of the composite aerogel is attributed to its surface charge, high interfacial activity, and unique brush-like structure. A demulsification mechanism based on the synergistic effect of surface charge and molecular brush is proposed to elucidate the efficient demulsification process.

Fabrication of biodegradable and cold-water-soluble starch/polyvinyl alcohol films as inner packaging materials of pesticides: Enhanced emulsification, dispersibility, and efficacy.

Developing environmentally friendly film materials for packaging pesticides is significant yet challenging. The use of native starch for preparing inner packaging materials of pesticides is limited by its physicochemical properties. In this study, a novel strategy of synergetic mechanical activation (MA)-enhanced solid-phase esterification of starch and cooperative combination of starch and polyvinyl alcohol (PVA) was proposed to fabricate biodegradable and cold-water-soluble starch (St)/PVA films. The appropriate esterification of starch and favorable compatibility between starch and PVA contributed to the production of St/PVA films by the extrusion-blowing method. The as-prepared film with St/PVA ratio of 4:6 exhibited outstanding mechanical properties (tensile strengths of 21.0 MPa; elongation at break of 213.9 %), cold-water solubility (dissolution time of 90 s), and oxygen barrier performance (oxygen transmission rate of 1.41 cm3/(m2·day·bar)). The dissolved St/PVA films with amphiphilic groups were conducive to the emulsification of butachlor (a fat-soluble liquid pesticide) and the dispersibility of oxyfluorfen (a fat-soluble solid pesticide). Furthermore, a mechanism of the interaction between pesticides and the surface of weed leaves was proposed to reveal the enhanced efficacy of St/PVA films-packaged pesticides. The strategy based on MA-enhanced esterification and PVA blending is efficient to produce starch-based films suitable for inner packaging materials of pesticides.

Effects of sevoflurane on left ventricular function by speckle-tracking echocardiography in coronary bypass patients: A randomized trial.

The present study aimed to dynamically observe the segmental and global myocardial movements of the left ventricle during coronary artery bypass grafting by transesophageal speckle-tracking echocardiography, and to assess the effect of sevoflurane on cardiac function. Sixty-four patients scheduled for the off-pump coronary artery bypass grafting were randomly divided into a sevoflurane-based anesthesia (AS) group and a propofol-based total intravenous anesthesia (AA) group. The AS group demonstrated a higher absolute value of left ventricular global longitudinal strain than that of the AA group at both T 1 (after harvesting all grafts and before coronary anastomosis) and T 2 (30 min after completing all coronary anastomoses) ( P < 0.05). Moreover, strain improvement in the segment with the highest preoperative strain was significantly reduced in the AS group, compared with the AA group at both T 1 and T 2 ( P < 0.01). The flow of the left internal mammary artery-left anterior descending artery graft was superior, and the postoperative concentration of troponin T decreased rapidly in the AS group, compared with the AA group ( P < 0.05). Compared with total intravenous anesthesia, sevoflurane resulted in a significantly higher global longitudinal strain, stroke volume, and cardiac output. Sevoflurane also led to an amelioration in the condition of the arterial graft. Furthermore, sevoflurane significantly reduced strain improvement in the segmental myocardium with a high preoperative strain value. The findings need to be replicated in larger studies.

Effect of Gut Microbiota on the Pharmacokinetics of Nifedipine in Spontaneously Hypertensive Rats.

The pharmacokinetic variability of nifedipine widely observed in the clinic cannot be fully explained by pharmacogenomics. As a new factor affecting drug metabolism, how the gut microbiota affects the pharmacokinetics of nifedipine needs to be explored. Spontaneously hypertensive rats (SHRs) have been commonly used in hypertension-related research and served as the experimental groups; Wistar rats were used as control groups. In this study, the bioavailability of nifedipine decreased by 18.62% (p < 0.05) in the SHRs compared with the Wistar rats. Changes in microbiota were associated with the difference in pharmacokinetics. The relative abundance of Bacteroides dorei was negatively correlated with AUC0-t (r = -0.881, p = 0.004) and Cmax (r = -0.714, p = 0.047). Analysis of serum bile acid (BA) profiles indicated that glycoursodeoxycholic acid (GUDCA) and glycochenodeoxycholic acid (GCDCA) were significantly increased in the SHRs. Compared with the Wistar rats, the expressions of CYP3A1 and PXR were upregulated and the enzyme activity of CYP3A1 increased in the SHRs. Spearman's rank correlation revealed that Bacteroides stercoris was negatively correlated with GUDCA (r = -0.7126, p = 0.0264) and GCDCA (r = -0.6878, p = 0.0339). Moreover, GUDCA was negatively correlated with Cmax (r = -0.556, p = 0.025). In primary rat hepatocytes, GUDCA could induce the expressions of PXR target genes CYP3A1 and Mdr1a. Furthermore, antibiotic treatments in SHRs verified the impact of microbiota on the pharmacokinetics of nifedipine. Generally, gut microbiota affects the pharmacokinetics of nifedipine through microbial biotransformation or by regulating the enzyme activity of CYP3A1.

Direct and efficient conversion of cellulose to levulinic acid catalyzed by carbon foam-supported heteropolyacid with Brønsted-Lewis dual-acidic sites.

This study aimed to produce bio-based levulinic acid (LA) via direct and efficient conversion of cellulose catalyzed by a sustainable solid acid. A carbon foam (CF)-supported aluminotungstic acid (HAlW/CF) catalyst with Brønsted-Lewis dual-acidic sites was creatively engineered by a hydrothermal impregnation method. The activity of the HAlW/CF catalyst was determined via the hydrolysis and conversion of cellulose to prepare LA in aqueous system. The cooperative effect of Brønsted and Lewis acids in HAlW/CF resulted in high cellulose conversion (89.4%) and LA yield (60.9%) at 180 °C for 4 h, which were greater than the combined catalytic efficiencies of single HAlW and CF under the same conditions. The HAlW/CF catalyst in block form exhibited superior catalytic activity, facile separation from reaction system, and favorable reusability. This work offers novel perspectives for the development of recyclable dual-acidic catalysts to achieve one-pot catalytic conversion of biomass to value-added chemicals.

Practical Electrochemical Method to Enhance Needle Visibility during Ultrasound Imaging.

Ultrasound-guided needle interventions play a pivotal role in the diagnosis and treatment processes in clinical practice. However, existing echogenic needles face challenges in achieving a balance between effectiveness, ease of manufacturing, and inexpensiveness. In this study, we developed an echogenic needle that encompassed the aforementioned advantages through the use of the electrolysis technology. The overall contour of the needle after electrolysis was observed using bright-field microscopy, while scanning electron microscopy (SEM) was employed to examine the micro-variations on the needle's surface. Subsequently, we validated the enhanced visualization effects in vitro (pork) and in vivo (anesthetized rabbit's thigh) puncture phantoms. To ensure the safety of the needles after the puncture procedure, we conducted Vickers hardness tests, SEM detection, bright-field microscopy, and DAPI staining. The results demonstrated that the surface roughness of the needle increased with the duration of electrolysis. Taking into account the comprehensive safety tests, the needle, subjected to 40 s of electrolysis, demonstrated a safe and effective enhancement of ultrasound visualization.

Characteristics, Thrombus Resolution, and Long-Term Outcomes in Patients with Nonvalvular Atrial Fibrillation and Atrial Thrombus.

To assess the prevalence and management of atrial thrombus in patients with nonvalvular atrial fibrillation (NVAF) and identify the risk factors of the nonresolution of atrial thrombus. This single-center retrospective observational study consecutively enrolled patients with NVAF and atrial thrombus detected using transesophageal echocardiography (TEE) or cardiac computed tomography angiography (CTA) from January 2012 to December 2020. Patients with prior left atrial appendage (LAA) intervention were excluded. The primary endpoint was the presence of atrial thrombus, while the secondary endpoint was the complete resolution of atrial thrombus. The prevalence of atrial thrombus in patients with NVAF was 1.4%. Ninety patients with atrial thrombus (mean age 62.8 ± 11.9 years and 61.1% men) were finally analyzed. Atrial thrombus was in the LAA in 82 (91.1%) patients. During follow up, 60% of the patients showed complete resolution of atrial thrombus. Congestive heart failure (odds ratio [OR]: 8.94; 95% confidence interval [CI]: 1.67-47.80) and a history of ischemic stroke (OR: 8.28; 95% CI: 1.48-46.42) were independently associated with the risk of the nonresolution of atrial thrombus. The presence of atrial thrombus in patients with NVAF who received anticoagulation therapy is non-negligible. Even in anticoagulated patients, TEE or cardiac CTA might still be needed. Congestive heart failure and a history of ischemic stroke are risk factors of the nonresolution of atrial thrombus.

Facile solid-phase synthesis of starch-fatty acid complexes via mechanical activation for stabilizing curcumin-loaded Pickering emulsions.

Starch-fatty acid complexes used as emulsifiers have caught great attention because of their renewability and excellent emulsifying property, the development of a simple and efficient synthesis method for the fabrication of starch-fatty acid complexes is still greatly challenging. Herein, the rice starch-fatty acid complexes (NRS-FA) were successfully prepared by mechanical activation method using different long chain fatty acids (myristic acid, palmitic acid, and stearic acid) and native rice starch (NRS) as the raw materials. The results showed that the prepared NRS-FA with a V-shaped crystalline structure exhibited a higher digestion resistance than NRS. Moreover, when the chain length of fatty acids increased from 14 to 18 carbons, the contact angle of the complexes was much closer to 90°, and the average particle size was smaller, deriving the better emulsifying property of NRS-FA18 complexes, which were suitable to be used as an emulsifier to stabilize curcumin-loaded Pickering emulsions. The results of storage stability and in vitro digestion showed that the curcumin retention could reach 79.4 % after 28 days of storage and 80.8 % of curcumin was retained in the system after simulated gastric digestion, showing good encapsulation and delivery performance of prepared Pickering emulsions, which attributed to the enhancement of the coverage of particles at the oil-water interface.

Construction of a stable biochar-supported amorphous aluminum solid acid catalyst with Brønsted-Lewis dual acid sites for efficient conversion of cellulose.

The development of sustainable catalysts for the efficient conversion of biomass to desirable chemicals is significant and challenging. Herein, a stable biochar (BC)-supported amorphous aluminum solid acid catalyst with Brønsted-Lewis dual acid sites was constructed through one-step calcination of a mechanical activation (MA)-treated precursor (starch, urea, and Al(NO3)3). The as-prepared N-doped BC (N-BC)-supported Al composite (MA-Al/N-BC) was used for the selective catalytic conversion of cellulose to produce levulinic acid (LA). MA treatment promoted uniform dispersion and stable embedding of Al-based components in the N-BC support with nitrogen- and oxygen-containing functional groups. This process provided the MA-Al/N-BC catalyst with Brønsted-Lewis dual acid sites and improved its stability and recoverability. When the MA-Al/N-BC catalyst was used under optimal reaction conditions (180 °C, 4 h), it achieved a cellulose conversion rate of 93.1% and a LA yield of 70.1%. Additionally, it also showed high activity for catalytic conversion of other carbohydrates. The results of this study offer a promising solution for the production of sustainable biomass-derived chemicals through the use of stable and eco-friendly catalysts.

Retrogradation behavior of starch dough prepared from damaged cassava starch and its application in functional gluten-free noodles.

A novel starch-based model dough used to exploit staple foods was demonstrated to be feasible, which was based on damaged cassava starch (DCS) obtained by mechanical activation (MA). This study focused on the retrogradation behavior of starch dough and the feasibility of its application in functional gluten-free noodles. Starch retrogradation behavior was investigated by low field-nuclear magnetic resonance (LF-NMR), X-ray diffraction (XRD), scanning electron microscope (SEM), texture profile and resistant starch (RS) content analysis. During starch retrogradation, water migration, starch recrystallization and microstructure changes were observed. Short-term retrogradation could significantly alter the texture properties of starch dough, and long-term retrogradation promoted the formation of RS. The damage level influenced starch retrogradation, and damaged starch with the increasing damage level was beneficial to facilitate the starch retrogradation. Gluten-free noodles made from the retrograded starch had acceptable sensory quality, with darker color and better viscoelasticity than Udon noodles. This work provides a novel strategy for the proper utilization of starch retrogradation for the development of functional foods.

Double-template-regulated biomimetic construction and tribological properties of superdispersed calcium borate@polydopamine/cellulose acetate-laurate nanocomposite.

Herein, a novel superdispersed calcium borate@polydopamine/cellulose acetate-laurate nanocomposite (CTAB-CB@PDA/CAL) is successfully synthesized by a double-template-regulated biomimetic mineralization strategy using PDA/CAL as a hard template and cetyltrimethylammonium bromide (CTAB) as a soft template and surface hydrophobic modifier. The results show that CB can grow uniformly on the CAL surface, and CTAB can improve the hydrophobicity of CTAB-CB@PDA/CAL due to the synergistic effect of the double templates, which contributes to the enhanced dispersibility and long-term dispersion stability of CTAB-CB@PDA/CAL in poly-alpha-olefin (PAO) base oil. Furthermore, CB can rapidly enter the friction interface due to the long substituents of CTAB and CAL, so CTAB-CB@PDA/CAL used as a lubricant additive in PAO base oil exhibits superior tribological performance compared to CB, CB/CAL, and CB@PDA/CAL.

Myocardial work and energy loss of left ventricle obtained by pressure-strain loop and vector flow mapping: a new perspective on idiopathic left bundle branch block.

Background: To date, no research has been conducted on the electrical activity and mechanical dyssynchrony of idiopathic left bundle branch block (iLBBB) with normal left ventricular ejection fraction (LVEF). This study sought to assess the left ventricular summation of energy loss (EL-SUM) and average energy loss (EL-AVE) using vector flow mapping as well as myocardial work using pressure-strain loop (PSL) in patients with iLBBB and normal LVEF. Methods: We prospectively recruited 35 patients with iLBBB and 35 control participants with normal LVEF. Echocardiography was performed. Conventional echocardiographic parameters, myocardial work, and energy loss (i.e., the EL-SUM and EL-AVE) were calculated. Results: In relation to global myocardial work, compared to the control participants, the iLBBB patients showed decreased global longitudinal strain (GLS; -15.32%±2.58% vs. -18.27%±2.12%; P=0.001), a decreased global work index (GWI; 1,428.24±338.18 vs. 1,964.87±264.16 mmHg%; P<0.001), decreased global work efficiency (GWE) (84.48±5.19 vs. 91.73±5.31 mmHg%; P<0.001), and significantly increased global waste work (GWW; 341.60±132.62 vs. 161.80±106.81 mmHg%; P<0.001). In relation to the regional index, the iLBBB patients had a significantly reduced basal anteroseptal segment (879.15±370.50 vs. 1,746.38±154.44 mmHg%; P<0.001), basal inferoseptal segment (1,111.42±389.04 vs. 1,677.25±223.10 mmHg%; P<0.001), mid-anteroseptal segment (1,097.54±394.83 vs. 1,815.06±291.22 mmHg%; P<0.001), mid-inferoseptal segment (1,012.54±353.33 vs. 1,880.88±254.39 mmHg%; P<0.001), apical anterior segment (1,592.42±366.64 vs. 1,910.00±170.27 mmHg%; P=0.001), apical lateral segment (1,481.62±342.95 vs. 1,817.19±227.55 mmHg%; P=0.001), apical septal segment (1,437.65±428.22 vs. 1,852.25±275.19 mmHg%; P=0.001), and apex (1,542.62±342.89 vs. 1,907.06±197.94 mmHg%; P<0.001). The iLBBB patients had increased EL-AVE and EL-SUM during the late-diastole, isovolumic-systole, and rapid-ejection periods [EL-AVE in T2: 28.3 (8.7, 49.0) vs. 6.8 (5.4, 9.4) J/(s·m3); P=0.029]; [EL-AVE in T3: 24.7 (13.0, 46.8) vs. 7.2 (5.4, 10.8) J/(s·m3), P<0.001]; [EL-AVE in T4: 18.3 (12.0, 27.6) vs. 7.7 (4.1, 11.6) J/(s·m3), P=0.002]; [EL-SUM in T2: 8.3 (2.2, 14.5) vs. 2.1 (1.6, 3.2) J/(s·m), P=0.049]; [EL-SUM in T3: 7.6 (4.0, 14.5) vs. 2.2 (1.7, 3.3) J/(s·m), P<0.001]; [EL-SUM in T4: 5.3 (3.6, 9.7) vs. 2.2 (1.4, 3.0) J/(s·m), P=0.004]. Conclusions: The GWI and GWE were reduced in patients with iLBBB, especially in the septum and apex. The EL-SUM and EL-AVE were higher in patients with iLBBB during the late-diastole, isovolumic-systole, and rapid-ejection periods. EL and PSL reflect the LV hemodynamics of patients with iLBBB.

Antibiotics-Induced Depletion of Rat Microbiota Induces Changes in the Expression of Host Drug-Processing Genes and Pharmacokinetic Behaviors of CYPs Probe Drugs.

The metabolism of exogenous substances is affected by the gut microbiota, and the relationship between them has become a hot topic. However, the mechanisms by which the microbiota regulates drug metabolism have not been clearly defined. This study characterizes the expression profiles of host drug-processing genes (DPGs) in antibiotics-treated rats by using an unbias quantitative RNA-sequencing method and investigates the effects of antibiotics-induced depletion of rat microbiota on the pharmacokinetic behaviors of cytochrome P450s (CYPs) probe drugs, and bile acids metabolism by ultra-performance liquid chromatography-tandem mass spectrometry. Our results show that antibiotics treatments altered the mRNA expressions of 112 DPGs in the liver and jejunum of rats. The mRNA levels of CYP2A1, CYP2C11, CYP2C13, CYP2D, CYP2E1, and CYP3A of CYP family members were significantly downregulated in antibiotics-treated rats. Furthermore, antibiotics treatments also resulted in a significant decrease in the protein expressions and enzyme activities of CYP3A1 and CYP2E1 in rat liver. Pharmacokinetic results showed that, except for tolbutamide, antibiotics treatments significantly altered the pharmacokinetic behaviors of phenacetin, omeprazole, metoprolol, chlorzoxazone, and midazolam. In conclusion, the presence of stable, complex, and diverse gut microbiota plays a significant role in regulating the expression of host DPGs, which could contribute to some individual differences in pharmacokinetics. SIGNIFICANCE STATEMENT: This study investigated how the depletion of rat microbiota by antibiotics treatments influences the expression profiles of host DPGs and the pharmacokinetic behaviors of CYPs probe drugs. Combined with previous studies in germ-free mice, this study will improve the understanding of the role of gut microbiota in drug metabolism and contribute to the understanding of individual differences in the pharmacokinetics of some drugs.

Resource utilization of pig hair to prepare low-cost adsorbents with high density of sulfhydryl for enhanced and trace level removal of aqueous Hg(II).

Pig hair (PH), a keratinous waste, was modified by ammonium thioglycolate in a ball milling to promote its performance of Hg(II) sequestration. The ball milling broke the hydrophobic cuticle sheath and enhanced the reduction of disulfide bond, which increased the sulfydryl content of the modified PH (BTPH) from 0.07 to 11.05 µmol/g. BTPH exhibited a significantly higher capture capacity of Hg(II) (415.4 mg/g) than PH (3.1 mg/g), as well as the commercial activated carbon (219.7 mg/g), and persisted its performance over a wide range of solution pH. Meanwhile, BTPH with a distribution coefficient of 5.703 × 105 mL/g could selectively capture Hg(II) from the water with the coexisting metal ions such as Mg(II), Cd(II) and Pb(II). Moreover, the low-cost BTPH could reduce the Hg(II) from 1.0 mg/L to well below the limit of drinkable water (2 µg/L) in real-world samples. Density functional theory (DFT) calculations and state-of-the-art characterizations illustrated that the binding of Hg(II) to sulfydryl groups was the main adsorption mechanism. Notably, BTPH decreased the mercury content of water spinaches from 24.1 to 0.50 mg/kg and thereby significantly reduced the phytotoxicity of Hg(II). This work therefore provides a sustainable way to utilize keratinous wastes for the remediation of aqueous Hg(II).

Influence of a single hemodialysis on left ventricular energy loss and wall shear stress in patients with uremic cardiomyopathy assessed with vector flow mapping.

Background: The influence of hemodialysis (HD) on hydromechanics of the left ventricle has not been reported. This study evaluated the left ventricular summation of energy loss (EL-SUM), average energy loss (EL-AVE), and wall shear stress (WSS) before and after HD using vector flow mapping (VFM) in patients with end-stage renal disease (ESRD). Methods: We prospectively recruited 40 patients receiving long-term HD and excluded those with structural cardiac disease. Echocardiography was performed before and within 24 hours after HD. Conventional echocardiographic parameters, summation, and average energy loss (EL-SUM, EL-AVE, EL-base, EL-mid and EL-apex), and WSS in each segment were compared. Results: A total of 40 patients with uremia were recruited. After HD, left ventricular EL-AVE-total, and EL-SUM-total decreased significantly in the early diastolic [29.43 (18.76 to 46.28) vs. 17.70 (10.76 to 95.60) N/(m2·s) and 12 (6 to 17) vs. 5 (3 to 11) e-2 J; P<0.001, respectively], mid-diastolic [17.07 (10.38 to 24.35) vs. 10.29 (5.86 to 16.30) N/(m2·s) and 7 (3 to 10) vs. 4 (2 to 6) e-2 J; P<0.001, respectively], and early systolic [17.82 (12.79 to 24.77) vs.14.90 (10.23 to 19.05) N/(m2·s) P=0.011 and 8 (5 to 11) vs. 5 (4 to 8) e-2 J, P=0.002, respectively] phases. It was revealed that HD did not change EL-AVE-total and EL-SUM-total in the late diastolic and late systolic phases. The EL-AVE decreased after HD in the left ventricular (LV) basal [50.70 (24.19 to 77.92) vs. 26.00 (11.50 to 47.68) N/(m2·s); P<0.001] and mid [15.52 (8.88 to 20.90) vs. 9.47 (6.41 to 14.21) N/(m2·s); P=0.001] segments during the early diastolic phase; in the LV basal [18.64 (10.33 to 29.80) vs. 10.25 (6.98 to 19.43) N/(m2·s); P<0.001), mid (15.70 (9.93 to 23.08) vs. 9.99 (6.03 to 16.25) N/(m2·s); P<0.001), and apical [9.78 (4.06 to 15.77) vs. 4.52 (3.14 to 10.36) N/(m2·s); P=0.001) segments during the mid-diastolic phase; in the LV mid [14.34 (8.34 to 23.88) vs. 9.36 (6.48 to 17.05) N/(m2·s); P=0.013] and apex [11.25 (6.37 to 21.88) vs. 6.60 (5.33 to 12.17) N/(m2·s); P=0.016] segments during the late diastolic phase; and in the apical [10.28 (6.05 to 17.01) vs. 7.59 (3.73 to 13.20) N/(m2·s) P=0.025] segment during the early systolic phase. After HD, WSS significantly reduced in the mid-diastolic [0.51 (0.32 to 0.69) vs. 0.38 (0.30 to 0.46) Pa, P=0.001] and early systolic [0.60 (0.45 to 0.81) vs. 0.57 (0.42 to 0.68) Pa, P=0.029] phases. There was no change in WSS during the early diastolic, late diastolic, and late systolic phases. Conclusions: After HD, EL and WSS of LV decrease during the systolic and diastolic phases. The VFM can reflect the LV hemodynamics in patients undergoing HD under different fluid loads.

Stroke risk evaluation for patients with atrial fibrillation: Insights from left atrial appendage with fluid-structure interaction analysis.

The majority of cardioembolic strokes in patients with non-valvular atrial fibrillation (NVAF) are resulted from clot formation in the left atrial appendage (LAA). Current stroke risk stratification is based on the overall risks estimated from demographic and clinical profiles but not on individual anatomy or physiology. We aim to explore the differences in LAA morphological and hemodynamic parameters by comparing patients with and without a stroke history. Thirty-nine patients with persistent NVAF were included. Of these, 17 patients without a stroke history (non-stroke group) were compared with 22 patients with a history of stroke (stroke group). Their LAA geometric models were first reconstructed, and the morphological parameters were then measured. Furthermore, their LAA hemodynamic parameters were calculated by fluid-structure interaction analysis. Moreover, particle residual rates (PRR) and blood renewal rates (BRR) analyses were also employed to characterize the thrombogenesis dynamics. The results showed that compared to the non-stroke group, the stroke group had significant smaller LAA tortuosity and LAA orifice area, and significantly lower LAA orifice velocities (0.16 ± 0.10 vs 0.15 ± 0.06 cm/s; p = 0.044), but higher PRR (14.58 ± 9.43 vs 9.25 ± 4.67; p = 0.040) and BRR (52.41 ± 18.11 vs 38.36 ± 24.07; p = 0.044). These LAA morphological and hemodynamic parameters may be used to assess stroke risk in patients with NVAF.

Low-Temperature-Graphitized and Interpenetrating Network C/Fe3O4 Magnetic Nanocomposites with Enhanced Tribological Properties under High Temperature.

Although the core-shell structure magnetic nanocomposites have been widely used as lubricant additives, their tribological properties are still poor under high temperature and high load. Herein, the graphitized C/Fe3O4 magnetic nanocomposites (g-C/Fe3O4) with an interpenetrating network structure were successfully fabricated by an in situ hydrothermal carbonization method combined with a subsequent ball milling process at room temperature. The results showed that the ball milling process not only promoted the transformation of graphitized carbon but also effectively eliminated the interfacial effect between carbon and Fe3O4. Moreover, the g-C/Fe3O4 used as a lubricant additive in rapeseed oil exhibited excellent tribological properties and high thermo-stability under 155 °C and 980 N, with the friction coefficient reduced by 32.8% compared to the independent Fe3O4. The enhanced tribological performance of g-C/Fe3O4 could be attributed to the graphitized carbon and its interpenetrating network structure under low load force (392 N), while under high load force (980 N), it could be ascribed to the synergistic effect between the graphitized carbon and magnetic Fe3O4 nanoparticles. This work not only offers a method for the synthesis of nanocomposite lubricant additives but also shows great potential in practical applications for high-temperature tribology.

Fast-thermoresponsive carboxylated carbon nanotube/chitosan aerogels with switchable wettability for oil/water separation.

The use of aerogels to selectively recover oil from oily wastewater is effective but challenging. In this study, a new carboxylated carbon nanotube/chitosan aerogel (CCNT/CA) with switchable wettability was developed as a smart adsorbent for fast oil absorption and oil recovery. Vinyltrimethoxysilane and thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) was grafted onto the surface of the CCNT/CA skeleton, and the resulting smart aerogel (PNI-Si@CCNT/CA) exhibited temperature responsiveness. PNI-Si@CCNT/CA exhibited an excellent reversible conversion between hydrophilicity and hydrophobicity when the temperature was changed to below or above the lower critical solution temperature (LCST) of PNIPAAm (~32 °C). Most importantly, CCNT significantly increased the oil absorption capacity, improved the mechanical properties, accelerated phonon conduction, enhanced thermal conductivity (80.57 mW m-1 K-1), improved the temperature response rate, shortened the oil desorption time (15 min), and improved the oil/water separation efficiency of PNI-Si@CCNT/CA because a strong interface interaction occurred between CCNT and chitosan. Moreover, PNI-Si@CCNT/CA absorbed oil at 45 °C and released the absorbed oil at 25 °C. It maintained its good adsorption performance after 15 cycles, and this was ascribed to its excellent mechanical properties and stable structure.