Prenatal features and postnatal follow-up of congenital ventricular outpouching: A retrospective study of two centers in China.

OBJECTIVES: Congenital ventricular outpouching (CVO) is a rare cardiac malformation that can manifest as congenital ventricular aneurysm (CVA) and/or congenital ventricular diverticula (CVD). In this study, we describe the prenatal features and postnatal follow-up of 27 cases of CVO. METHODS: The clinical data of 27 patients with CVO who attended Sir Run Run Shaw Hospital Affiliated to the Medical College of Zhejiang University (Zhejiang Province, China) and Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University (Zhejiang Province, China) from April 2013 to October 2022 were retrospectively analyzed. The patients were also followed up by telephone. The prenatal characteristics and postnatal outcomes of the patients with CVO were evaluated. RESULTS: CVO was detected in 26 cases prenatally, 14 (51.85%) were diagnosed with CVA, nine (33.33%) were diagnosed with CVD, three (11.11%) were equivocal for CVA/CVD, and one (3.70%) was detected with CVA postnatally. Six patients underwent follow-up fetal echocardiography approximately 4 weeks after the initial echocardiography examination, and a significant difference in CVO size was observed between the two examinations (P = .02). Eight patients (29.63%) demonstrated cardiovascular dysfunction, and the median CVO size in fetuses with and without cardiovascular dysfunction was 205 (range: 169-396) mm2 and 124 (range: 92-154.5) mm2 , respectively (P = .01). Correlation was found between CVO size and fetal cardiac dysfunction (p = .000, r = .778). Eight patients (29.63%) had cardiac/extracardiac defects. Thirteen patients were live born, 12 were terminated pregnancies, and two were lost to follow-up. The postpartum size of the CVOs remained stable in six patients, decreased in two patients, dissolved in three patients, and were surgically removed in two patients. With the exception of one patient with CVA complicated with complex congenital cardiac malformation who underwent surgical treatment after birth and who had postoperative left ventricular dysfunction (Case 1), the prognosis of all of the patients was good. CONCLUSION: CVO is often associated with cardiac malformations. The size of prenatal CVOs can increase with gestational development, and cardiovascular dysfunction is significantly related to CVO size. The postpartum prognosis of patients with CVO is good. Echocardiography plays a key role in the diagnosis of congenital ventricular outpouching. Prenatal counseling should be cautious regarding the diagnosis and the prognosis although our cases had a favorable prognosis.

Soft-Hard Janus Nanoparticles Triggered Hierarchical Conductors with Large Stretchability, High Sensitivity, and Superior Mechanical Properties.

There is a long-standing conflict between the large stretchability and high sensitivity for strain sensors, a strategy of decoupling the mechanical/electrical module by constructing the hierarchical conductor has been developed in this study. The hierarchical conductor, consisting of a mechanically stretchable layer, a conductive network layer, and a strongly bonded interface, can be produced in a simple one-step process with the aid of soft-hard Janus nanoparticles (JNPs). The introduction of JNPs in the stretchable layer can evenly distribute stress and dissipate energy due to forming the rigid-flexible homogeneous networks. Specifically, JNPs can drive graphene nanosheets (GNS) to fold or curl, creating the unique JNPs-GNS building block that can further construct the conductive network. Due to its excellent deformability to hinder crack propagation, the flexible conductive network could be stretched continuously and the local conductive pathways could be reconstructed. Consequently, the hierarchical conductor could detect both subtle strain of 0-2% and large strain of up to 370%, with a gauge factor (GF) from 66.37 to 971.70, demonstrating outstanding stretchability and sensitivity. And it also owns large tensile strength (5.28 MPa) and high deformation stability. This hierarchical design will give graphene-based sensors a major boost in emerging applications.

Active control of terahertz waves based on hybrid VO2 periodic corrugated waveguides.

We describe a method for the active control of terahertz (THz) waves using hybrid vanadium dioxide (VO2) periodic corrugated waveguide. Unlike liquid crystals, graphene and semiconductors and other active materials, VO2 exhibits a unique insulator-metal transition characteristic by the electric fields, optical, and thermal pumps, resulting in five orders of magnitude changes in its conductivity. Our waveguide consists of two gold coated plates with the VO2-embedded periodic grooves, which are placed in parallel with the grooves face to face. Simulations show that this waveguide can realize mode switching by changing the conductivity of the embedded VO2 pads, whose mechanism is attributed to the local resonance induced by defect mode. Such a VO2-embedded hybrid THz waveguide is favorable in practical applications such as THz modulators, sensors and optical switches, and provides an innovative technique for manipulating THz waves.

Surface Charge Density Gradient Printing To Drive Droplet Transport: A Numerical Study.

Traditional strategies, such as morphological or chemical gradients, struggle to realize the high-velocity and long-distance transport for droplets on a solid surface because of the pinning hydrodynamic equilibrium. Thus, there is a continuing challenge for practical technology to drive droplet transport over the last decades. The surface charge density (SCD) gradient printing method overcame the theoretical limit of traditional strategies and tackled this challenge [Nat. Mater. 2019, 18: 936], which utilized the asymmetric electric force to realize the high-velocity and long-distance droplet transport along a preprinted SCD gradient pathway. In the present work, by coupling the electrostatics and the hydrodynamics, we developed an unexplored numerical model for the water droplet transporting along the charged superhydrophobic surface. Subsequently, the effects of SCD gradients on the droplet transport were systematically discussed, and an optimized method for SCD gradient printing was proposed according to the numerical results. The present approach can provide early guidance for the SCD gradient printing to drive droplet transport on a solid surface.

In vivo study on the repairment of distal femur defects in rabbit with nano-pearl powder bone substitute. / çº³ç±³çç ç²‰äººå·¥éª¨ä¿®å¤å ”è‚¡éª¨è¿œç«¯ç¼ºæŸ.

OBJECTIVES: To evaluate the repairing ability of nano-pearl powder bone substitute in rabbit with defect of distal femur bone. METHODS: Thirty-two New Zealand rabbits were randomly divided into four groups: a nano-pearl powder/recombinant human bone morphogenetic protein 2 (rhBMP-2)/hyaluronic acid group, a nano-pearl powder/hyaluronic acid group, a nano-pearl powder group and a blank control group (n=8 in each group). A defect with the diameter of 7 mm and height of 10 mm was prepared at the distal femoral metaphysis line of the rabbit.Different bone substitutes were planted, and the effect of repair was evaluated by macroscopic observation, imaging examination, and histopathological examination. RESULTS: The results of imageology showed that: the bone repairing effect in the nano-pearl powder/rhBMP-2/hyaluronic acid group was better than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group, and which in the 3 experimental groups was better than that in the blank control group; The results of histology showed that: at the 4th, 8th and 12th weeks after the modeling operation, the speed of bone repair in the nano-pearl powder/rhBMP-2/hyaluronic acid group was faster than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group, and which in the blank control group was far slower than that in the 3 experimental groups. The results of immunohistochemistry staining for osteocalcin antibody showed that: the osteogenic effect in the nano-pearl powder/rhBMP-2/hyaluronic acid group was better than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group (both P<0.05); there was no significant difference between the nano-pearl powder/hyaluronic acid group and the pure pearl powder group (P>0.05); however, there was significant difference between the pure pearl powder group and the blank control group (P<0.05). According to the staining results of Type I collagen antibody, there was no significant difference in the osteogenic effect between the nano-pearl powder/rhBMP-2/hyaluronic acid group and the nano-pearl powder/hyaluronic acid group (P>0.05), but the osteogenic effect in the nano-pearl powder/hyaluronic acid group was better than that in the pure pearl powder group and the blank control group (both P<0.05). CONCLUSIONS: Nano-pearl powder and its bone substitute can promote the repair of bone defect, and the nano-pearl powder which contains rhBMP-2 has better osteogenic and repairing effect on defect.

The Strengthening and Toughening of Biodegradable Poly (Lactic Acid) Using the SiO2-PBA Core-Shell Nanoparticle.

The balance of strengthening and toughening of poly (lactic acid) (PLA) has been an intractable challenge of PLA nanocomposite development for many years. In this paper, core-shell nanoparticles consisting of a silica rigid core and poly (butyl acrylate) (PBA) flexible shell were incorporated to achieve the simultaneous enhancement of the strength and toughness of PLA. The effect of core-shell nanoparticles on the tensile, flexural and Charpy impact properties of PLA nanocomposite were experimentally investigated. Scanning electron microscopy (SEM) and small-angle X-ray scattering (SAXS) measurements were performed to investigate the toughening mechanisms of nanocomposites. The experimental results showed that the addition of core-shell nanoparticles can improve the stiffness and strength of PLA. Meanwhile, its elongation at break, tensile toughness and impact resistance were enhanced simultaneously. These observations can be attributed to the cavitation of the flexible shell in core-shell nanoparticles and the resultant shear yielding of the matrix. In addition, a three-dimensional finite element model was also proposed to illustrate the damage processes of core-shell nanoparticle-reinforced polymer composites. It was found that, compared with the experimental performance, the proposed micromechanical model is favorable to illustrate the mechanical behavior of nanocomposites.

Tensile, Quasistatic and Dynamic Fracture Properties of Nano-Al2O3-Modified Epoxy Resin.

Epoxy resin, modified with different particle sizes (50 nm, 100 nm, 200 nm) and contents (1 wt %, 3 wt %, 5 wt %, 7 wt %) was manufactured. The mechanical behaviors of tensile, quasistatic fracture and dynamic fracture under SHPB (split Hopkinson pressure bar) loading were investigated. The dynamic fracture behaviors of the composites were evaluated by 2D-DIC (digital image correlation) and the strain gauge technique, and the fracture surface was examined by SEM (scanning electron microscope). According to the results, the tensile modulus and strength significantly increased for epoxy resin modified with 5 wt % Al2O3 of 50 nm. The quasistatic fracture toughness of modified epoxy resin increased with the particle content. However, the fracture toughness of epoxy resin modified with high content fillers decreased for particle agglomeration that existed in epoxy resin. The crack propagation velocity can be decreased for epoxy resin modified with particles under dynamic loading. The dynamic initiation fracture toughness of modified epoxy resin increases with both particle size and content, but when the fillers have a high content, the particle size effects are weak. For the composite under dynamic loading conditions, the toughening mechanism is also affected by particle size.

The removal efficiency of constructed wetlands filled with the zeolite-slag hybrid substrate for the rural landfill leachate treatment.

The removal efficiencies of two horizontal subsurface flow constructed wetlands (HSSF CWs, down-flow (F1) and up-flow (F2)) filled with the zeolite-slag hybrid substrate for the rural landfill leachate treatment were investigated. The adsorption experiment was conducted to evaluate the potential of zeolite and slag as the wetland substrate. The effects of distance variations along the longitudinal profile of wetland bed on pollutant removal were assessed by sampling at four locations (inlet, outlet, 0.55 m, and 1.10 m from the inlet). During the operation time, the influent and effluent concentrations of chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total nitrogen (TN), heavy metals, and polycyclic aromatic hydrocarbon (PAH) were measured. The results showed that the constructed wetlands were capable of removing COD, 20.5-48.2% (F1) and 18.6-61.2% (F2); NH3-N, 84.0-99.9% (F1) and 93.5-99.2% (F2); TN, 80.3-92.1% (F1) and 80.3-91.2% (F2); and heavy metals, about 90% (F1 and F2). The zeolite-slag hybrid substrate performed excellent removal efficiency for the nitrogen and heavy metals. The inlet area was the most active region of leachate removal. The up-flow constructed wetland (F2) has a higher removal efficiency for the PAH compounds. The significant removal efficiency illustrated that the rural landfill leachate can be treated using the horizontal subsurface flow constructed wetland filled with the zeolite-slag hybrid substrate.

COD removal efficiency and mechanism of HMBR in high volumetric loading for ship domestic sewage treatment.

The hybrid membrane bioreactor (HMBR) has been applied in ship domestic sewage treatment under high volumetric loading for ship space saving. The mechanism and influence factors on the efficiency, including hydraulic retention time (HRT), dissolved oxygen (DO) of chemical oxygen demand (COD) removal were investigated. The HMBR's average COD removal rate was up to 95.13% on volumetric loading of 2.4 kgCOD/(m3•d) and the COD concentration in the effluent was 48.5 mg/L, far below the International Maritime Organization (IMO) discharge standard of 125 mg/L. DO had a more remarkable effect on the COD removal efficiency than HRT. In addition, HMBR revealed an excellent capability of resisting organics loading impact. Within the range of volumetric loading of 0.72 to 4.8 kg COD/(m3•d), the effluent COD concentration satisfied the discharge requirement of IMO. It was found that the organics degradation in the aeration tank followed the first-order reaction, with obtained kinetic parameters of vmax (2.79 d-1) and Ks (395 mg/L). The original finding of this study had shown the effectiveness of HMBR in organic contaminant degradation at high substrate concentration, which can be used as guidance in the full scale of the design, operation and maintenance of ship domestic sewage treatment devices.

[Quality comparison between two cultivated Chinese yam-Kunming yam and Tiegun yam].

OBJECTIVE: To compare the quality of cultivated Chinese yam (Dioscorea polystachya Turcz.) from Yunnan (Kunming yam) and Henan (Tiegum yam) by determining the content of dry substance in fresh sample and the contents of water extracts, ethanol extracts, starch, protein, crude-fat and polysaccharide in dry sample. METHOD: The above-mentioned indexes were determined by methods of air desiccation, cold-immersing, hot-immersing, iodine-blue coloration, half Micro-Kjeldahl, Soxhlet extraction and spectrophotometric method respectively. RESULT: In fresh sample, the content of dry substance of Kunming yam is a little lower than Tiegun yam; in dry sample, all indexes of Kunming yam are higher than or approach to those of Tiegun yam except the content of crude-fat. Especially the content of polysaccharide in Kunming yam is 64% higher than that of Tiegun yam. CONCLUSION: Kunming yam, with high quality, high yield and good taste, deserves paying close attention as a good variety.