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Herein, we analyzed total polyphenol content, total flavonoid content, and the antioxidant activity of the ethanol and distilled water extracted Houttuynia cordata perennial herb. Later, we investigated the possibility of producing Houttuynia cordata extract (HCE) loaded Polyurethane (PU) nanofibers via the electrospinning technique. The analysis confirmed that the total polyphenol, total flavonoid content, and antioxidant activity of the ethanol extracted HCE were higher than the distilled water extracted HCE. Therefore, the ethanol extracted HCE was used to prepare HCE/PU nanofibers by varying concentrations of HCE and PU. The HCE/PU nanofibers showed a mixed pattern of beads and fibers at a PU concentration of 10 wt%. However, at 12 wt% PU concentration, relatively uniform nanofibers with an average diameter of about 200 nm were formed at 1.0% and 1.5 wt% of HCE. The successful incorporation of HCE in PU nanofibrous matrix was confirmed by the presence of its characteristic bands in Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectra. The addition of HCE increased the crystallinity, the amount of heat required for pyrolysis, and the thermal stability of HCE/PU nanofibers, which must be credited to the HCE-derived quercitrin and quercetin crystallite solids.

Objectives To explore the causes of sudden unexpected death (SUD) and to search for high-risk people, whole exome sequencing (WES) was performed in families with SUDs. Methods Whole exome sequencing of 25 people from 14 SUD families were screened based on cardiac disease-associated gene variants, and their echocardiograms and electrocardiograms (ECG) were also examined. The protein function of mutated genes was predicted by SIFT, PolyPhen2 and Mutation Assessor. Results In the group of 25 people from 14 SUD families, 49 single nucleotide variants (SNVs) of cardiac disease-associated genes were found and verified by Sanger sequencing. 29 SNVs of 14 cardiac disorder-related genes were predicted as pathogens by software. Among them, 7 SNVs carried by two or more members were found in 5 families, including SCN5A (c.3577C > T), IRX4 (c.230A > G), LDB3 (c.2104 T > G), MYH6 (c.3G > A), MYH6 (c.3928 T > C), TTN (c.80987C > T) and TTN (c.8069C > T). 25 ECGs were collected. In summary, 4 people had J-point elevation, 2 people had long QT syndrome (LQTS), 4 people had prolonged QT interval, 3 people had T-wave changes, 3 people had sinus tachycardia, 4 people had sinus bradycardia, 4 people had left side of QRS electrical axis, and 3 people had P wave broadening. Echocardiographic results showed that 1 person had atrial septal defect, 1 person had tricuspid regurgitation, and 2 people had left ventricular diastolic dysfunction. Conclusions Of the 14 heart disease-associated genes in 14 SUDs families, there are 7 possible pathological SNVS may be associated with SUDs. Our results indicate that people with ECG abnormalities, such as prolonged QT interval, ST segment changes, T-wave change and carrying the above 7 SNVs, should be the focus of prevention of sudden death.

Adding fumed silica (SiO2) has been considered as an effective method for tailoring the phase morphology and performance of elastomer-toughened plastic binary blends. It has been demonstrated that the selective distribution of SiO2 plays a decisive role in the mechanical properties of plastic/elastomer/SiO2 nanocomposites, especially for the impact toughness. In this work, we aim to illuminate the role of specific surface area in controlling their selective distribution of fumed SiO2 and consequent mechanical properties of plastic/elastomer binary blends. Three types of SiO2 with different specific surface areas were incorporated into polylactide/ethylene-co-vinyl-acetate (PLA/EVA) model blends by melt blending directly. It was found that the selective distribution of SiO2 is largely determined by their specific surface areas, i.e. SiO2 nanoparticles with low specific surface area has a stronger tendency to be located at the interface between PLA matrix and EVA dispersed phase as compared to those with high specific surface area. The specific surface area-dependent interfacial selective distribution of SiO2 is mainly attributed to the extent of increased viscosity of EVA dispersed phase in which SiO2 nanoparticles are initially dispersed and resultant migration rate of SiO2 nanoparticles. The interfacial localized SiO2 nanoparticles induce an obvious enhancement in the impact toughness with strength and modulus well maintained. More importantly, in the case of the same interfacial distribution, toughening efficiency is increased with the specific surface area of SiO2. Therefore, this is an optimum specific surface area of SiO2 for the toughening. This work not only provides a novel way to manipulate the selective distribution of SiO2 in elastomer-toughened plastic blends toward high-performance, but also gives a deep insight into the role of interfacial localized nanoparticles in the toughening mechanism.

Graphdiyne (GDY) is emerging as a promising material for various applications owing to its unique structure and fascinating properties. However, the application of GDY in electronics and optoelectronics are still in its infancy, primarily owing to the huge challenge in the synthesis of large-area and uniform GDY film for scalable applications. Here a modified van der Waals epitaxy strategy is proposed to synthesize wafer-scale GDY film with high uniformity and controllable thickness directly on graphene (Gr) surface, providing an ideal platform to construct large-scale GDY/Gr-based optoelectronic synapse array. Essential synaptic behaviors have been realized, and the linear and symmetric conductance-update characteristics facilitate the implementation of neuromorphic computing for image recognition with high accuracy and strong fault tolerance. Logic functions including “NAND” and “NOR” are integrated into the synapse which can be executed in an optical pathway. Moreover, a visible information sensing-memory-processing system is constructed to execute real-time image acquisition, in situ image memorization and distinction tasks, avoiding the time latency and energy consumption caused by data conversion and transmission in conventional visual systems. These results highlight the potential of GDY in applications of neuromorphic computing and artificial visual systems.

The genetic diversity and mating status of seed production stands are crucial factors impacting the genetic quality and ecological stability of progeny plantations. The genetic homogeneity of seeds collected from a seed production population in different years has not yet been clearly described. In this study, the genetic diversity and differentiation of a seed-tree stand of 58-year-old Pinus massoniana (P1959) and four-open pollinated plantations of its progeny (OS1996, OS2000, OS2006 and OS2015) were determined by using microsatellite markers. The results showed that similar high genetic diversity was preserved in the seed-tree stand and its four progenies. This implied that current artificial seed harvesting from the seed-tree stand for reforestation does not lead to a significant reduction in genetic diversity; the F index across most loci was significantly greater than zero, indicating population homozygote excess. The pairwise genetic differentiation of the five populations ranged from 0.035 to 0.075, among which OS2015 was the most differentiated from the parent. The differentiation between the parental population and its progeny seemed to increase with increasing age of the seed-trees. This implied that a limited pollination coupled with variable within-stand pollen availability has created opportunities for both self- and foreign pollination to be successful in various periods, resulting in a seemingly paradoxical scenario of both high selfing and gene flow, ultimately resulting in gradually increasing differences in the gene frequency composition between the parental population and its progeny. Management considerations in addressing these problems in similar seed production stands were discussed.

Rhizoctonia solani is the causal agent of stem canker and black scurf in potato, resulting in significant yield and economic losses. To understand the infection process of R. solani and potato responses to the pathogen, histological observation of inoculated potato was performed under light and electron microscopes, under laboratory conditions. R. solani was observed at the invasion site, for the initial infection time, and for the presence of infection structures (appressoria, infection cushions). These attributes were compared when R. solani affected different parts of the host: aboveground stems, underground stems, tubers; as well as in different potato cultivars: ‘Desiree’ (resistant to R. solani) and ‘Atlantic’ (susceptible). In aboveground stems of potato, the invasion of R. solani was mainly limited to intercellular spaces. In underground stems and tubers, the primary invasion sites were epidermal cracks and lenticels. Initial infection time was 8 to 12 h post inoculation (HPI) in aboveground stems, 8 HPI in underground stems, and 4 HPI in tubers. The hyphae of R. solani produced various infection structures, with a few infection cushions, and a large number of appressoria with different morphologies. In aboveground stems, more infection structures were found than in underground stems and tubers. ‘Desiree’ had fewer numbers and smaller sizes of lenticels, thicker cuticle and periderm, and fewer epidermal cracks compared to ‘Atlantic’. Fewer numbers of infection structure of R. solani were observed in ‘Desiree’ than in ‘Atlantic’. It was suggested that the epidermal and perithelial structures of potato were related to disease resistance, such as number and size of lenticels, thickness of cuticle and periderm, and epidermal cracks.

Three new complexes, {[Cu3(2,3-pyma)2(sip)2(H2O)5]·5H2O} n , {[Zn(H-2,3-pyma)(sip)(H2O)]·H2O} n , and {[Cd(H-2,3-pyma)(sip)(H2O)]·H2O} n (2,3-pyma = (2-pyridylmethyl,3-pyridylmethyl)amine and H3sip = 5-sulfoisophthalic acid) were synthesized and structurally characterized by single-crystal X-ray diffraction. The Cu(II) complex crystallizes in neutral two-dimensional layers in which the Cu(II) centers are bridged by both the flexible 2,3-pyma and the rigid sip ligands. The Zn(II) and Cd(II) complexes contain neutral one-dimensional chains linked by the rigid sip anions, whereas the flexible H-2,3-pyma ions only act as terminal ligands. The Cu(II) complex shows weak antiferromagnetic interactions, while the Zn(II) and Cd(II) complexes exhibit fluorescent emissions in the solid state.

Three new complexes, {[Mn(Hbpma)2(pm)(H2O)2]·8H2O}n, {[Co(Hbpma)2(pm)(H2O)2]·8H2O}n and {[Zn(Hbpma)2(pm)(H2O)2]·8H2O}n (bpma = N,N′-bis(3-pyridylmethyl)amine and H4pm = pyromellitic acid) were synthesized and structurally characterized by single-crystal X-ray diffraction. All three complexes are isomorphous consisting of one-dimensional coordination polymers bridged by rigid pm ligands, while the flexible dipyridyl bpma only acts as a terminal ligand. The bpma ligand adopts the trans–trans conformation in all three complexes. The magnetic properties of the Mn(II) and Co(II) complexes show the occurrence of antiferromagnetic interactions between adjacent metal atoms. The Zn(II) complex exhibits fluorescent emission in the solid state at room temperature.

The changes of microbial community during agricultural waste composting were successfully studied by quinone profiles. Mesophilic bacteria indicated by MK-7 and mesophilic fungi containing Q-9 as major quinone were predominant and seemed to be important during the initial stage of composting. Actinobacteria indicated by a series of partially saturated and long-chain menaquinones were preponderant during the thermophilic period. While Actinobacteria, fungi and some bacteria, especially those microbes containing MK-7(H4) found in Gram-positive bacteria with a low G+C content or Actinobacteria were found cooperate during the latter maturating period. Since lignocellulose is abundant in the agricultural wastes and its degradation is essential for the operation of composting, it's important to establish the correlation between the quinone profiles changes and lignocellulose degradation. The microbes containing Q-9 or Q-10(H2) as major quinone were found to be the most important hemicellulose and cellulose degrading microorganisms during composting. While the microorganisms containing Q-9(H2) as major quinone and many thermophilic Actinobacteria were believed to be responsible for lignin degradation during agricultural waste composting.