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Nodal link semimetals as a type of topological semimetals are characterized by the nodal link rings in the Brillouin zone. The magneto-optical conductivity of nodal link semimetals is investigated numerically based on a system with a magnetic field. We find that in the system, the Landau levels (LLs) and magnetic field show a relationship of three halves power, which can lead to an intricate curved LLs. Due to the rich structure of LLs, we divided the LLs into four different regions to calculate the magneto-optical conductivity. We calculated the absorption peaks of longitudinal and Hall conductance of a neutral system and with different chemical potential. We find that the absorption peaks of longitudinal conductance are in a curved background in the whole range of magnetic field. When chemical potential is tuned to pass through the LLs, there are not only the intraband transition but also weak redistributed peaks in the low frequency. From the transition peaks of Hall conductance, we can find that there are several negative peaks because of the striking LLs spectrum structure. This will provide a feasible way to distinguish nodal link semimetals from other materials. [ABSTRACT FROM AUTHOR]

Background: Dandy-Walker syndrome (DWS) is a rare congenital malformation of the central nervous system (CNS), characterized by underdevelopment or dysplasia of the cerebellar vermis, expansion of the fourth ventricle and posterior fossa cistern. The incidence is aboutapproximately 1/25000–1/35000. At present, the etiology and pathogenesis of DWS are not completely clear. It is mostly considered to be a multifactorial genetic disease that is related to both genetic factors and environmental factors. There is no large sample size analysis of the chromosomal profile of DWS up to now. This study aims to provide clinical reference for prenatal diagnosis via summarizing the clinical features and pregnancy outcomes of Dandy-Walker syndrome. Methods: A total of 76 cases of foetal Dandy-Walker syndrome out of 19,506 pregnant women underwent cordocentesis or amniocentesis for genetic detection. Rapid prenatal karyotyping, single nucleotide polymorphism array (SNP-array) and BACs-on-Beads™ (BoBs) were performed for prenatal genetic diagnosis. The results of ultrasonography, genetic analysis and pregnancy outcome were recorded. Results: Of the 76 cases, 19 were isolated DWS, while 57 cases were accompanied by other ultrasound-visible abnormalities. Ultrasound abnormalities of the CNS were most frequently observed, accompanied by DWS. Twenty-five out of 76 cases had chromosomal abnormalities, and the rate of chromosomal abnormalities increased in pregnant women of advanced maternal age or in combination with other ultrasound abnormalities. Of the 19 cases in the isolated DWS group, nine pregnant women chose to terminate the pregnancy, while seven cases continued the pregnancy and all infants were normal. Among the 57 pregnant women with pathological ultrasound manifestations other than foetal DWS, 44 chose to terminate the pregnancy, while 12 cases continued the pregnancy. Further follow-up revealed one newborn with postnatal neurodevelopmental delay. A female term neonate presented with very severe sensorineural deafness, and an infant died 7 days after birth with abnormal development of multiple organs. Conclusions: Pregnant women with DWS in foetal ultrasonic examination should be offered a careful and comprehensive foetal ultrasound scan and further prenatal genetic testing including karyotype analysis and SNP-array. The prognosis of the foetus without chromosomal aberration is good in isolated DWS pregnancies but poor in nonisolated DWS pregnancies. [ABSTRACT FROM AUTHOR]

The gapless edge states with a certain spin and valley index can be realized in topological domain walls. In this work, we study various domain walls thoroughly and demonstrate that multiple kinds of edge states with a perfect spin and valley polarization can be realized, leading to the possibility of establishing spin filters and spin-valley filters. Moreover, the spin and valley index of the edge states can be tuned by an external electric field. We also investigate the finite size effect on the edge states when two domain walls approach each other. Generally, the finite size effect can cause the hybridization of edge states and open a gap. We find that the evolutions of the bandgap as a function of the finite size effect for different topological edge states are distinguished from each other. [ABSTRACT FROM AUTHOR]

In recent years, advanced oxidation process (AOPs) based on sulfate radical (SO4●−) and singlet oxygen (1O2) has attracted a lot of attention because of its characteristics of rapid reaction, efficient treatment, safety and stability, and easy operation. SO4●− and 1O2 mainly comes from the activation reaction of peroxymonosulfate (PMS) or persulfate (PS), which represent the oxidation reactions involving radicals and non-radicals, respectively. The degradation effects of target pollutants will be different due to the type of oxidant, reaction system, activation methods, operating conditions, and other factors. In this paper, according to the characteristics of PMS and PS, the activation methods and mechanisms in these oxidation processes, respectively dominated by SO4●− and 1O2, are systematically introduced. The research progress of PMS and PS activation for the degradation of organic pollutants in recent years is reviewed, and the existing problems and future research directions are pointed out. It is expected to provide ideas for further research and practical application of advanced oxidation processes dominated by SO4●− and 1O2. [ABSTRACT FROM AUTHOR]

The pyrabactin resistance (PYR)/PYR-like (PYL)/regulatory component of ABA receptor (RCAR) proteins are the core components in ABA signaling pathway. A salt and cold induced ABA receptor gene VsPYL5 from common vetch was identified in the present study. Transgenic Arabidopsis overexpressing VsPYL5 had increased ABA sensitivity and higher levels of seed germination rate, survival rate, and the maximal photochemical efficiency of photosystem II (F v /F m) than the wild type (WT) under salinity conditions. Lower levels of the temperature that leads to 50% electrolyte leakage (TEL 50) and higher levels of survival rate after freezing treatment were observed in transgenic lines compared with WT. The results indicated that VsPYL5 regulated salt and cold tolerance positively. Lower levels of Na+ and Na+/K+ ratio but higher levels of K+ and AKT1 , GORK , KAT1 , HKT1 and KUP4 transcripts were observed in transgenic lines compared with WT under salinity conditions. The results indicated that the increased salt tolerance in transgenic lines was associated with the altered Na+ and K+ levels as a result of improved expression of genes involved in Na+ and K+ homeostasis. Antioxidant enzyme activities and their encoding gene transcripts, proline concentration and reactive oxygen species (ROS) levels were increased after treatment with salinity or cold, with lower levels in transgenic lines compared with WT. It is suggested that VsPYL5 -regulated salt and cold tolerance was associated with the increased proline level and antioxidant defense capacity for maintenance of ROS as a result of improved the relevant gene expression under salinity and cold conditions. Overexpression of VsPYL5 led to increased salt and cold tolerance through improved expression of genes involved in Na+ and K+ homeostasis and ROS homeostasis and increased antioxidant defense capacity • Transgenic Arabidopsis overexpressing VsPYL5 had increased ABA sensitivity and enhanced salt and cold tolerance. • Transgenic lines had lower levels of Na+ but higher levels of K+ under salinity conditions. • Maintenance of ROS were associated with cold and salt tolerance in transgenic lines. [ABSTRACT FROM AUTHOR]

• The electronic simulation of the from pressure stimuli to nociceptors was conducted. • A bionic sensory system has been developed to present tactile perception. • The piezoelectric film sensor serves as an electronic skin. • The NiAl-LDHs/gelatin heterojunction memristor emulates biological nociceptors. • The essential characteristics of nociceptors, including threshold, no adaptation, relaxation, and sensitization were demonstrated. The sensations of touch and pain are fundamental components of our daily existence, serving as conduits for providing crucial insights into our environment and ensuring the safeguarding of our health. To date, the exploration of artificial systems that combine pain and touch perception has remained very limited. Moreover, memristor based visualization of pain degree is rarely reported. The electronic simulation of the from pressure stimuli to nociceptors was conducted in this work. For this purpose, a bionic sensory system has been developed to present tactile perception. In this system, the piezoelectric film sensor serves as an electronic skin to mimic artificial mechanoreceptors for sensing external pressure stimulation and generating signals. Meanwhile, the Ni-Al layered double hydroxides (LDHs)/gelatin heterojunction memristor emulates biological nociceptors to receive and process receptor signals, with luminous diode used as displays to indicate the degree of artificial contusion. The Ni-Al LDHs/gelatin heterojunction memristor demonstrates essential characteristics of nociceptors, including threshold, no adaptation, relaxation, and sensitization phenomena of allodynia and hyperalgesia. This biomimetic artificial tactile and pain perception system successfully simulates the perception threshold and sensitivity to pressure stimuli. The potential ability of humanoid robots could be demonstrated by utilizing the system as an artificial tactile alarm system. [ABSTRACT FROM AUTHOR]

In this work, a resistive switching memory device was fabricated based on egg protein, a natural biomaterial. The effect of graphene composite on the resistive switching characteristics of the device was investigated. The experimental results show that both pure egg protein and graphene composite devices exhibit bipolar nonvolatile resistive conversion properties. Both devices have good data retention capability. Furthermore, the composite of graphene can effectively improve the device endurance and the consistency of the on-state current distribution of the device. Based on the theory of capture and de-capture of charge carrier, the mechanism of resistive switching is analyzed. The biological egg protein was used as functional layer, and graphene was used as channel medium and trap layer material. Then, the effect of graphene composite on biological egg protein resistance switching memory properties was investigated. The endurance property and the consistency of the on-state current distribution of the device have been effectively improved by the composite of graphene. [ABSTRACT FROM AUTHOR]

Many ingredients in Wenshen Shengjing Decoction (WSSJD) can cause epigenetic changes in the development of different types of cells. It is not yet known whether they can cause epigenetic changes in sperms or early embryos. Here, we investigated the role of WSSJD in epigenetic modifications of sperms or early embryos and early embryo development. A mouse model with spermatogenesis disorders was established with cyclophosphamide (CPA). WSSJD was administrated for 30 days. The male model mice after the treatment were mated with the female mice treated with superovulation. The embryo development rate of each stage was calculated. Immunofluorescence staining was used to detect the expression of H3K27me3 in sperm, pronuclear embryos, and 2-cell embryos. Western blotting was used to detect the expression of histone demethylase KDM6A and methyltransferase EZH2 in 2-cell embryos with developmental arrest. The expressions of zygotic genome activation genes (ZSCAN4, E1F1AX, HSPA1A, ERV4-2, and MYC) in 2-cell embryos with developmental arrest were analyzed with qRT-PCR. Comparing with the control group, CPA destroyed the development of seminiferous epithelium, significantly increased the expression level of H3K27me3 in sperm, reduced the expression ratio of H3K27me3 in female and male pronuclei, delayed the development of 2-cell embryos, and increased the developmental arrest rate and degeneration rate of 2-cell embryos. Moreover, the expressions of EZH2 and H3K27me3 were significantly increased in the 2-cell embryos with developmental arrest, and the expression of zygotic genome activation genes (ZSCAN4, E1F1AX, HSPA1A, ERV4-2, and MYC) was significantly decreased. Compared with the CPA group, WSSJD promoted the development of seminiferous epithelium, maintained a low level of H3K27me3 modification in sperm and male pronucleus, significantly increased the development rate of 2-cell embryos and 3-4 cell embryos, and reduced the developmental arrest rate and degeneration rate of 2-cell embryos. WSSJD may promote early embryonic development by maintaining a low level of H3K27me3 modification in sperm and male pronucleus and regulating the zygotic genome activation in mice with spermatogenesis disorders induced by CPA. [ABSTRACT FROM AUTHOR]

The synaptic behavior of the Ni–Co layered double hydroxide-based memristor was demonstrated. The modulation effect of pulse amplitude, duration, and excitation interval on the conductance of memristor is analyzed. On account of analog resistive switching features, and the nonlinear transmission characteristics of synapses, pulse-time-dependent plasticity, long-term/short-term memory, and "learning" and "forgetting" behaviors of synapses are simulated and carried out. The analog bipolar resistance switch was ascribed to the formation and breakdown of oxygen filaments formed in Ni–Co layered double hydroxides films. This kind of memristor with an analog resistance switch is very promising to provide an implementation method for the development of electronic synapse function. [ABSTRACT FROM AUTHOR]

The bionic features offered by memory device are being actively explored. However, two-terminal memristors exhibit variability and limited capacity due to their inherent single presynaptic input scheme. Compared with the two-terminal memristor, the memtransistor can realize the modulation of conductive channel through the synergistic effect of gate, which enables the multifunctional modulation. Here, based on Schottky barrier tuning at metal-semiconductor interfaces by means of ferroelectric domain switching, a programmable memtransistor with arithmetic calculating and logic function is realized. Memtransistor with drain and gate adjustable non-volatile memory function effectively simulates the plasticity of biological synapses. Moreover, four arithmetical operations: addition, subtraction, multiplication and division are carried out by using the synaptic device. At the same time, the logic gate functions of "XOR" and "XNOR" were implemented based on ferroelectric memtransistor. This result will be helpful to further promote the development of memory computing for synaptic devices. [ABSTRACT FROM AUTHOR]

Organic materials are the key to the next generation of electric memory elements because of their low cost, high flexibility and high scalability. Solution-processed n-channel and p-channel organic field effect transistors (FETs) by spinning coating technique was demonstrated. We use based-poly (vinylcarbazole) (PVK) p-type transistor and based-6-phenyl-C61 butyric acid methyl ester (PCBM) n-type transistor as the channel of bottom gate structure FET, respectively, to fabricate the complementary inverter. The maximum voltage gain of the electrically isolated FET complementary inverter is up to 22, the power consumption is less than 3 μW, and the transition voltage is −4.2 V. In addition, our devices are able to implement "AND", "NAND", "OR", and "NOT" gate logic well. But more than that, p-type transistor based on PVK and n-type transistor based on PCBM were combined with the memristor, reward-modulated spike timing dependent plasticity was implemented by introduced reward/punishment signals to guide synaptic weight updates. It shows great potential in the electronic application system with low cost and high energy efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the pricing problems of European spread options with the floating interest rate. In this model, uncertain differential equation and stochastic differential equation are used to describe the fluctuation of stock price and the floating interest rate, respectively. We derive the pricing formulas for spread options including the European spread call option and the European spread put option. Finally, numerical algorithms are provided to illustrate our results. [ABSTRACT FROM AUTHOR]

Background: Although Chromosomal microarray analysis (CMA) is a powerful diagnostic technology for detecting chromosomal copy number variants (CNVs), it detects numerous variants of unknown significance (VUSs), which poses a great challenge for genetic counselling. Terminal deletion of the long arm of chromosome 4 is a rare genetic aberration. Few cases of interstitial deletion sharing the common deleted segment have been reported. Case presentation: A male foetus with a 7.22-Mb deletion at chromosome 4q32.2q32.3 was found in the proband. The paternal genotype was normal. His asymptomatic mother with a normal phenotype and intelligence was found to carry the same deletion at the long arm of chromosome 4. The clinical significance of arr[GRCh37] 4q32.2q32.3(162858958_170081268)×1 remains uncertain. To the best of our knowledge, this is the first case report on a VUS of 4q32 deletion and the second report of a heterochromatic CNV involving part of the long arm of chromosome 4 in a phenotypically normal mother and child. The identification of this case contributes to additional understanding of deletion at 4q32.2q32.3. This report may provide a reference for prenatal diagnosis and genetic counselling in patients who have genotypes of similar cytogenetic abnormalities. Conclusions: The novel 7.22-Mb deletion at chromosome 4q32.2q32.3 (162858958-170081268) is a VUS. The foetus inherited this VUS from a phenotypically normal mother. [ABSTRACT FROM AUTHOR]

Bacteriophages (phages), or bacterial viruses, have recently received increasing attention, especially considering pan-drug-resistant bacteria, and studies on lytic bacteriophage proteins would help develop antibiotic candidates to treat these bacterial infections. We previously isolated and sequenced a Streptomyces avermitilis bacteriophage, phiSASD1. This study aimed to clone and express ORF40 and ORF19, previously predicted as endolysin (termed LytSD) and holin (termed HolSD), two crucial phage proteins involved in host lysis. The yield of LytSD was 17.2 mg per liter of culture, and the optimal lysis conditions were investigated. When applied exogenously, LytSD lysed 7/18 of the tested bacterial strains, including S. avermitilis , Bacillus subtilis , Staphylococcus aureus , Sarcina lutea , and Enterococcus faecalis. As regards HolSD, it resulted in growth inhibition of several tested strains and abrupt lysis of E. coli BL21 (DE3) pLysS; furthermore, it complemented the defective λ S allele of non-suppressing E. coli strains to produce phage plaques. Together, these results indicate the function of ORF40 and ORF19 of phage phiSASD1 and their potentials as novel antibiotics to inhibit or lyse pathogens. [ABSTRACT FROM AUTHOR]

Smith‒Magenis syndrome (SMS, OMIM: 182290) is a multiple congenital anomalies and intellectual disability syndrome due to a 3.45 Mb microdeletion involving 17p11.2 and is estimated to occur about one in 25,000 births. Up to now, the ultrasound findings of the foetus with SMS and their external genital defects in patients are rarely reported. This case indicates that foetus with SMS may present polyhydramnios and ventriculomegaly in the second trimester. The newborn male patient had an abnormal phenotype in which he has micropenis and his anus is close to the perineal body. The identification of this case may further expand the phenotypic spectrum of this genetic disorder. [ABSTRACT FROM AUTHOR]

Magnetic CuO nanosheet (Mag-CuO), as a cheap, stable, efficient and easily separated peroxymonosulfate (PMS) activator, was prepared by a simple one-step precipitation method for the removal of organic compounds from salt-containing wastewater. The experiments showed that the removal efficiencies of various organic pollutants including Acid Orange 7, Methylene Blue, Rhodamine B and atrazine in a high-salinity system (0.2 mol/L Na 2 SO 4) with the Mag-CuO/PMS process were 95.81%, 74.57%, 100% and 100%, respectively. Meanwhile, Mag-CuO still maintained excellent catalytic activity in other salt systems including one or more salt components (NaCl, NaNO 3 , Na 2 HPO 4 , NaHCO 3). A radical-quenching study and electron paramagnetic resonance analysis confirmed that singlet oxygen (1O 2) was the dominant reactive oxygen species for the oxidation of organic pollutants in high-salinity systems, which is less susceptible to hindrance by background constituents in wastewater than radicals (•OH or SO 4 •−). The surface hydroxylation of the catalyst and catalytic redox cycle including Cu and Fe are responsible for the generation of 1O 2. The developed Mag-CuO catalyst shows good application prospects for the removal of organic pollutants from saline wastewater. Unlabelled Image [ABSTRACT FROM AUTHOR]

Background: Cordocentesis in our practice is most commonly indicated for rapid karyotyping in the second or third trimester and is regarded as the gold standard for foetal chromosomal aberration diagnosis in pregnancies at high risk for chromosomal abnormalities. In this study, we investigated 3387 umbilical cord blood samples for karyotyping from pregnant women who underwent cordocentesis and explored the pregnancy outcomes of foetal sex chromosome mosaicism and chromosomal polymorphism. Results: Out of the 3387 samples, 182 abnormal karyotypes were detected. Ultrasound soft markers were the most common prenatal diagnostic indication, but the detection rate of abnormal karyotypes was 2.02%, while it was 46.97% in the genome-wide NIPT-positive group. The rate of aneuploidy was lower in the soft marker group than in the other groups. Out of 16 cases with sex chromosome mosaicism, three pregnant women with foetuses with a lower proportion of sex chromosome mosaicism delivered healthy foetuses; the foetus with karyotype 46,X,i(Y)(q10)[20]/45,X[6] showed unclear genitals. Three foetuses with chromosomal polymorphisms had postnatal disorders. Conclusions: NIPT should not be recommended as the first-tier screening for chromosomal aberration for pregnancies with ultrasound soft markers or pathological ultrasound findings, but NIPT can be considered an acceptable alternative for pregnancies with contraindications to cordocentesis or the fear of procedure-related foetal loss. Mosaicism found in amniotic fluid cell culture requires further cordocentesis for karyotype confirmation, and the continuation of pregnancy is safe when a normal karyotype is identified in foetal blood culture. Further genetic testing and parental karyotype analysis are needed for foetal chromosomal polymorphisms. [ABSTRACT FROM AUTHOR]

A multifunctional resistive switching memory devices with the typical sandwich structure of Al/Poly(4-vinylphenol) (PVP)+2-Amino-5-methyl-1,3,4-thiadiazole/Al is fabricated. Al as the bottom and top electrodes is easy to realize by simple thermal evaporation process, and a PVP and 2-Amino-5-methyl-1,3,4-thiadiazole composite film as the active layer is prepared by sol-gel method and spin coating process. The as-fabricated resistive switching memory device shows write-once-read-many (WORM) and rewritable multifunctional memory behaviors, for the rewritable and WORM memory modes, the ON/OFF ratio is 104 and 80, respectively. The as-fabricated device shows tristable conductivity states which equivalent to "0", "1" and "2", and these three conductance states are steady under the constant voltage retention test, as well as during the endurance test, indicating advantageous features of stable operation and dependable endurance. It is noteworthy that the simple preparation process is expected to promisingly hold the post of industrialization low-cost preparation in future electronic devices for ternary data storage utilities. • A multifunctional resistive switching memory devices was fabricated. • The as-fabricated device shows tristable conductivity states. • It is expected to promisingly hold the post of ternary data storage utilities. [ABSTRACT FROM AUTHOR]

In this work, a Ru(II) complex [Ru(bpy) 2 (pip-CO 2 H)]2+ (Ru 1) and its hexaarginine peptide conjugate [Ru(bpy) 2 (pic-Arg 6)]8+ (Ru 2) have been synthesized and characterized. The binding of Ru 1 and Ru 2 with poly(U)•poly(A)*poly(U) triplex has been studied. Results suggest that Ru 1 binds in the surface of the minor groove while Ru 2 binds to the minor groove of the triplex. Consequently, the triplex stabilization is barely affected by Ru 1 , while with Ru 2 the triplex stabilizing effect is so strong that that dissociation of the triplex shows an overlapping of both melting processes with the melting temperature increased to a maximum of 56.1 °C at the C Ru 2 / C UAU ratio of 0.05, where Δ T m1 and Δ T m2 are 19.6 and 10.1 °C, respectively. Furthermore, the effect of Ru 2 stabilizing the third strand at such a low binding ratio of 0.05 is more marked than what obsereved for flavone luteolin and [Ru(bpy) 2 (mdpz)]2+, which are so far the strongest triplex stabilizers in the reported organic small molecules and metal complexes, respectively. Considering the structure natures of Ru 2 , conceivably except for electrostatic interaction, the forces stabilizing the triplex should also involve hydrophobic interaction and hydrogen bingding. To our knowledge, this work represents a first example of improving the triplex stabilization by a metallopeptide. [ABSTRACT FROM AUTHOR]

• Ag-doped chitosan as function layer was employed to develop the bio-memristor. • A current–voltage (I-V) hysteresis with a typical capacitive effect is impressively observed. • Nonvolatile data storage is feasible using the non-zero-crossing I-V hysteresis. • The evolution of the resistive behavior of the memristor is observed. Three flexible transparent transient memristors based on degradable natural chitosan coating films are reported. The Mg/Ag-doped chitosan/ITO sandwich structures were prepared by spin coating and drop coating, respectively. The plane structure device was also prepared. Three kinds of device exhibit different memory behaviors, namely, bipolar resistive switching behavior and butterfly resistive switching behavior accompanied by capacitance and negative resistance effect. The elucidated behavior of the bipolar resistive switching can be attributed to filament conduction. The behavior of the butterfly resistive switching is attributed to interface effects. In addition, the three devices have a large on/off ratio and long data retention time, showing promising non-volatile memory characteristics in flexible memory applications. The switching mechanism was evaluated by Schottky emission, hopping and direct tunneling. The transient memristor device prepared in this paper has excellent transient characteristics and controllable performance. This work reveals the potential of biodegradable flexible electronic devices. [ABSTRACT FROM AUTHOR]

Abstract The influence of blending ratio on resistive switching effect in donor-acceptor type composite of [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM) and poly(N -vinylcarbazole) (PVK)-based memory devices are investigated. Current-voltage (I - V) curves for the ITO/PCBM + PVK/Al devices with 9 wt.% of PCBM showed a current bistability with a maximum OFF/ON resistance ratio of 9 × 104, which was 100 times larger than that of the device with 23 wt.% of PCBM and was 2000 times larger than that of the device with 41 wt.% of PCBM. Furthermore, the threshold voltage obviously decreased as the PCBM concentration increases. The retention time was above 105 s indicative of the memory stability of the as-fabricated devices. The I - V characteristics at OFF state dominantly comply with the rules of space-charge-limited-current behaviors, and I - V curve at ON state obey Ohmic laws. The proposed device suggests a promising approach for adjustale OFF/ON resistance ratio and threshold voltage in electronic memory devices. Graphical abstract Image Highlights • The influence of blending ratio on resistive switching effect are investigated. • The threshold voltage obviously decreased as the PCBM concentration increases. • The resistance ratio obviously increased with the PCBM concentration decreases. [ABSTRACT FROM AUTHOR]

Aims In order to investigate the effects and mechanism of Bisphenol A (BPA) on the growth of preantral follicles and the maturation of oocytes in vitro , preantral follicles were harvested from mouse ovaries and in vitro cultured for 11 days with different concentrations of BPA (0, 4.5 and 45 μM) for calculating the percentages of antral follicles, denuded oocytes, degenerative oocytes and the maturation rate of oocytes, besides measuring the diameter of follicles and the thickness of cumulus cell layers. Methods The contents of estradiol (E 2 ) in the culture media on Day 4, 8 and 10 were detected by ELISA. The estrogen receptor (ER) expression, spindle morphology and chromosome distribution in oocytes on Day 10 and 11 were observed by immunofluorescence. Western blotting was used to detect the expressions of growth differentiation factor 9 (GDF-9), bone morphogenetic protein-15 (BMP-15), phosphorylated extracellular signal-regulated kinase 1 (p-Erk1) and phosphorylated Ca 2 + /calmodulin-dependent protein kinase II (p-CaMKII) in the oocytes. Results Compared with control, BPA (45 μM) significantly reduced percentages of antral follicles (9.25% vs. 91.17%, P   <   0.05 ) and the maturation rate of oocytes (7.61% vs. 79.83%, P   <   0.05 ), but increased the percentages of denuded oocytes (30.29% vs. 3.36%, P   <   0.05 ) and degenerative oocytes (45.70% vs. 2.45%, P   <   0.05 ). The diameter of follicles and the thickness of the cumulus cell layers were decreased significantly ( P   <   0.05 ). Moreover, BPA (45 μM) significantly decreased E 2 contents in the culture medium on Day 8 and 10 ( P <   0.05 ) and the expressions of ER, GDF-9 and BMP-15 in oocytes ( P   <   0.05 ). Furthermore, BPA (4.5 and 45 μM) treatment resulted in the abnormal spindle morphology and chromosome distribution, and the decreased expressions of p-Erk1 and p-CaMKII in the MII oocytes. Conclusion Together, these results clearly demonstrated BPA retarded the preantral follicle growth in vitro through interfering with the synthesis and secretion of E 2 and reducing the expressions of ER, GDF-9 and BMP-15, and led to the abnormal meioses of oocytes through reducing p-Erk1 and p-CaMKII expressions in the preantral follicles, which will help us to further unsderstand the mechanism of BPA exposure retarding in vitro growth of preantral follicles and maturation of oocyes. [ABSTRACT FROM AUTHOR]

Common vetch (Vicia sativa L.) is a leguminous crop used to feed livestock with vegetative organs or fertilize soils by returning to the field. Survival of fall-seeded plants is often affected by freezing damage during overwintering. This study aims to investigate the transcriptomic profiling in response to cold in a mutant with reduced accumulation of anthocyanins under normal growth and low-temperature conditions for understanding the underlying mechanisms. The mutant had increased cold a tolerance with higher survival rate and biomass during overwintering compared to the wild type, which led to increased forage production. Transcriptomic analysis in combination with qRT-PCR and physiological measurements revealed that reduced anthocyanins accumulation in the mutant resulted from reduced expression of serial genes involving in anthocyanin biosynthesis, which led to the altered metabolism, with an increased accumulation of free amino acids and polyamines. The higher levels of free amino acids and proline in the mutant under low temperature were associated with improved cold tolerance. The altered expression of some genes involved in ABA and GA signaling was also associated with increased cold tolerance in the mutant. • The mutant had increased cold tolerance and reduced anthocyanin accumulation. • Expression of the genes associated with anthocyanin was reduced in the mutant. • The altered amino acid and polyamine concentrations were associated with cold tolerance. [ABSTRACT FROM AUTHOR]

We report the application of graphene oxide (GO) as the active layer of memory devices. The indium-tin-oxide/GO/Al devices present the ternary write-once-read-many times resistive switching memory, and retain the data information for 3 × 1 0 5 s. In the OFF states, the I – V characteristics in the applied voltage dominantly followed the space-charge-limited-current behaviors. The intermediate resistance state was attributed to the thermionic emission mechanism. In the ON state, the curve in the applied voltage range was related to an Ohmic mechanism. The sandwich structure, ITO/GO/Al resistive switching device, was fabricated. The as-fabricated devices exhibit nonvolatile ternary WORM features memory with retention performance of 3 × 1 0 5 s. The ternary WORM memory of ITO/GO/Al devices open up the door to the possibility of ultrahigh density data storage of high performance nonvolatile memory devices at low cost. [ABSTRACT FROM AUTHOR]

Microbes play important roles during river remediation and the interaction mechanism illustration between microorganisms and sewage is of great significance to improve restoration technology. In this study, micro-nano bubble and submerged resin floating bed composite technology (MBSR) was firstly used to restore two black and stinking urban rivers. After restoration, the water pollution indices such as dissolved oxygen (DO), ammonia nitrogen (NH 4 + -N), total phosphorous (TP), chemical oxygen demand (COD Cr ), water clarity, and the number of facial coliform were significantly improved. Microbial community composition and relative abundance both varied and more aerobic microbes emerged after remediation. The microbial changes showed correlation with DO, NH 4 + -N, TP and COD Cr of the rivers. In summary, the MBSR treatment improved the physiochemical properties of the two black and stinking urban rivers probably through oxygen enrichment of micro-nano bubble and adsorption of submerged resin floating bed, which thereby stimulated functional microbes to degrade pollutants. [ABSTRACT FROM AUTHOR]

Abstract: A non‐enzymatic electrochemical glucose sensor based on a Cu‐based metal‐organic framework (Cu‐MOF) modified electrode was developed. The Cu‐MOF was prepared by a simple ionothermal synthesis, and the characterizations of the Cu‐MOF were studied by Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), single‐crystal X‐ray powder diffraction (SCXRD), and X‐ray powder diffraction (XRD). Electrochemical behaviors of the Cu‐MOF modified electrode to glucose were measured by differential pulse voltammetry (DPV). The electrochemical results showed that the Cu‐MOF modified electrode exhibited an excellent electro‐catalytic oxidation towards glucose in the range of 0.06 μM to 5 mM with a sensitivity of 89 μA/mM cm2 and a detection limit of 10.5 nM. Moreover, the fabricated sensor showed a high selectivity to the oxidation of glucose in coexistence with other interferences. The sensor was satisfactorily applied to the determination of glucose in urine samples. With the significant electrochemical performances, MOFs may provide a suitable platform in the construction of kinds of electrochemical sensors and/or biosensors and hold a great promise for sensing applications. [ABSTRACT FROM AUTHOR]

Two-dimensional NiAl layered double hydroxides (LDHs) were synthesized by urea hydrolysis method. Considering its unique layered structure and high-speed carrier transfer channel, NiAl-LDHs were applied to the active layer of memristor through spin coating process. It is found that the Al/NiAl-LDHs/Al memristor exhibits unipolar resistance switching characteristics, which resistive switching mechanism is attributed to formation and fusing of conductive filaments controlled by oxygen vacancies. Based on this Al/NiAl-LDHs/Al memristor, a D -type latch was constructed. A memtransistor with Si/SiO 2 /graphene oxide (GO)/Al/NiAl-LDHs/Al structure was built by connecting Al/NiAl-LDHs/Al memristor in series on the drain electrode of GO transistor. The memtransistor exhibits excellent gate controllability and resistive switching characteristics. Combined with its characteristics, we used the memtransistor to build a D -trigger and verify its memory logical function. The result shows the great potential of layered bimetallic hydroxide materials in the field of resistance switching memory and memory computing. • The unipolar resistive switching characteristics of NiAl-LDHs memristor were investigated. • A D -type latch was constructed using NiAl-LDHs memristor, which logical function was verified. • A memtransistor was built by connecting Al/NiAl-LDHs/Al memristor in series on the drain electrode of GO transistor. • A D -trigger was constructed by the memtransistor, which exhibits excellent memory logical function. [ABSTRACT FROM AUTHOR]

Enshi City, in the Hubei Province of China, is known as the world capital of selenium with the most abundant selenium resource. An important selenium hyperaccumulator plant, Cardamine violifolia , was found to naturally grow in this high-selenium ecosystem. However, relatively little is known about the impact of the selenium levels on microbial community and functional shifts in C. violifolia rhizosphere. Here, we tested the hypothesis that underground microbial diversity and function vary along a selenium gradient, including antibiotic resistance genes (ARGs). Comprehensive metagenomic analyses, such as taxonomic investigation, functional detection, and ARG annotation, showed that selenium, mercury, cadmium, lead, arsenic, and available phosphorus and potassium were correlated with microbial diversity and function. Thaumarchaeota was exclusively dominant in the highest selenium concentration of mine outcrop, and Rhodanobacter and Nitrospira were predominant in the high-selenium ecosystem. The plant C. violifolia enriched a high concentration of selenium in the rhizosphere compared to those in the bulk soil, and it recruited Variovorax and Polaromonas in its rhizosphere. Microbial abundance showed a trend of increasing first and then decreasing from low to high selenium concentrations. Annotation of ARGs showed that the multidrug resistance genes ade F, mtr A, and poxt A, the aminoglycoside resistance gene rps L, and the sulfonamide resistant gene sul 2 were enriched in the high-selenium system. It was discovered that putative antibiotic resistant bacteria displayed obvious differences in the farmland and the soils with various selenium concentrations, indicating that a high-selenium ecosystem harbors the specific microbes with a higher capacity to enrich or resist selenium, toxic metals, or antibiotics. Taken together, these results reveal the effects of selenium concentration and the selenium hyperaccumulator plant C. violifolia on shaping the microbial functional community and ARGs. Metalloid selenium-inducible antibiotic resistance is worth paying attention to in future. [Display omitted] • Selenium is associated with a variety of toxic metals in the high-selenium system. • Low levels of selenium promote microbial growth, while high levels do the opposite. • Functional microbes such as Rhodanobacter and Variovorax were found in the high-selenium system. • Multidrug resistance genes were enriched in the high-selenium system. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants are thought to be potential reservoirs of antibiotic resistance genes. In this study, GeoChip was used for analyzing multiple antibiotic resistance genes, including four multidrug efflux system gene groups and three β-lactamase genes in ten large-scale membrane bioreactors (MBRs) for municipal wastewater treatment. Results revealed that the diversity of antibiotic genes varied a lot among MBRs, but about 40% common antibiotic resistance genes were existent. The average signal intensity of each antibiotic resistance group was similar among MBRs, nevertheless the total abundance of each group varied remarkably and the dominant resistance gene groups were different in individual MBR. The antibiotic resistance genes majorly derived from Proteobacteria and Actinobacteria. Further study indicated that TN, TP and COD of influent, temperature and conductivity of mixed liquor were significant ( P < 0.05) correlated to the multiple antibiotic resistance genes distribution in MBRs. [ABSTRACT FROM AUTHOR]

Two ruthenium(II) polypyridyl complexes containing 1,8-naphthalimide group as DNA binders, photonucleases, and inhibitors of topoisomerases I and IIα are evaluated. The binding properties of [Ru(phen) 2 (pnip)] 2 + { 1 ; phen = 1,10-phenanthroline; pnip = 12-[ N -( p -phenyl)-1,8-napthalimide]- imidazo[4′,5′- f ] [1,10]phenanthroline} and [Ru(bpy) 2 (pnip)] 2 + ( 2 ; bpy = 2,2′-bipyridine) with calf thymus DNA increases with increasing the bulkiness and hydrophobic character of ancillary ligands, although the two complexes possess high affinities for DNA via intercalation. Moreover, photoirradiation (λ = 365 nm) of the two complexes are found to induce strand cleavage of closed circular pBR322 plasmid DNA via singlet oxygen mechanism, while complex 1 displays more effective photocleavage activity than complex 2 under the same conditions. Topoisomerase inhibition and DNA strand passage assay reflect that complexes 1 and 2 are efficient dual poisons of topoisomerases I and IIα. [ABSTRACT FROM AUTHOR]

Stable RNA triplexes play key roles in many biological processes, while triplexes are thermodynamically less stable than the corresponding duplexes due to the Hoogsteen base pairing. To understand the factors affecting the stabilization of RNA triplexes by octahedral ruthenium(II) complexes, the binding of [Ru(bpy) 2 (ppn)] 2 + ( 1 , bpy = 2,2′-bipyridine, ppn = 2,4-diaminopyrimido[5,6-b]dipyrido[2,3-f:2′,3′-h]quinoxaline) and [Ru(phen) 2 (ppn)] 2 + ( 2 , phen = 1,10-phenanthroline) to poly(U)·poly(A)*poly(U) (· denotes the Watson-Crick base pairing and * denotes the Hoogsteen base pairing) has been investigated. The main results obtained here suggest that complexes 1 and 2 can serve as molecular “light switches” and stabilizers for poly(U)·poly(A)*poly(U), while the effectiveness of complex 2 are more marked, suggesting that the hydrophobicity of ancillary ligands has a significant effect on the two Ru(II) complexes binding to poly(U)·poly(A)*poly(U). This study further advances our knowledge on the binding of RNA triplexes with metal complexes, particularly with octahedral ruthenium polypyridyl complexes. [ABSTRACT FROM AUTHOR]

Membrane biofouling in membrane bioreactor (MBR), resulted from microbes and their associated extracellular polymeric substances (EPS), is a primary challenge for wide application of MBR. However, the dynamic change of microbes attached on membrane remains little understood. In the study, a pilot MBR was constructed to estimate the effects of online chemical cleaning on membrane biofouling and meanwhile to study the microbial compositions and dynamic change before and after online chemical cleaning. Results showed that the trans-membrane pressure (TMP) increased with running time and online chemical cleaning temporarily eased TMP. Using the scanning electron microscopy, it was clearly observed that the microbes adhered into the EPS and formed biofilm before online chemical cleaning, and the biofilm was disrupted and most microbes on the membrane surface were removed after online chemical cleaning. EPS assay results showed that online chemical cleaning removed most protein and humic substances, but only a little part of polysaccharide. Microbial phylogenetic cluster displayed that some microbes attached on the membrane were clustered together and obviously separated from those in the mixed liquor sludge, indicating the special property of the microbes on the membrane. The microbial community dynamic analysis demonstrated that the dominant group on the membrane was changed from Burkholderiaceae to Flavobacteriaceae and Saprospiraceae after online chemical cleaning. Furthermore, some microbes such as Acinetobacter , Xanthomonas , Cloacibacterium and Flavobacterium were found to repeatedly cause the membrane fouling. The results might be helpful for developing biological-based cleaning method and antifouling strategies in the future. [ABSTRACT FROM AUTHOR]

Common vetch (Vicia sativa L.) is an important leguminous crop, providing humans with starch from seeds, feeding livestock with vegetative organs, or fertilizing soils by returning to field. It is aimed to evaluate salt tolerance in common vetch collections for breeding programs and to investigate the underlined physiological mechanisms. Relative germination rate and relative seedling growth showed great difference among common vetch collections in response to salt. A lower level of Na+ and higher levels of K+ and K+/Na+ ratio were maintained in both shoots and roots in salt-tolerant collections than in salt-sensitive ones under salt stress. Expression of the genes involved in transportation and redistribution of Na+ and K+ were cooperatively responsible for salt stress. Transcript levels of NHX7 , HKT1 , AKT2, and HAK17 in leaves and roots were induced after salt stress, with higher transcript levels in salt-tolerant collections compared with the sensitive ones. Proline and P5CS1 transcript levels were increased after salt stress, with higher levels in salt-tolerant collection compared with salt-sensitive ones. Both O 2 − and H 2 O 2 were accumulated after salt stress, and lower levels were accumulated in salt-tolerant collection compared with salt-sensitive ones. Superoxide dismutase, catalase and ascorbate peroxidase activities were altered in response to salt and higher levels were maintained in salt-tolerant collections compared with salt-sensitive ones. It is suggested that salt tolerance in common vetch is associated with maintenance of K+ and Na+ homeostasis and the associated gene expression and promoted proline accumulation and antioxidant defense system. • Salt tolerant collections of common vetch were selected and identified. • Ion homeostasis, proline and antioxidants were associated with salt tolerance. • Salt tolerant collections had higher Na+ and K+ transporter transcripts under salinity. • Salt tolerant collections had higher levels of proline and antioxidants under salinity. [ABSTRACT FROM AUTHOR]

Synaptic behavior simulation in transistors based on MoS2 has been reported. MoS2 was utilized as the active layer to prepare ambipolar thin-film transistors. The excitatory postsynaptic current phenomenon was simulated, observing a gradual voltage decay following the removal of applied pulses, ultimately resulting in a response current slightly higher than the initial current. Subsequently, ±5 V voltages were separately applied for ten consecutive pulse voltage tests, revealing short-term potentiation and short-term depression behaviors. After 92 consecutive positive pulses, the device current transitioned from an initial value of 0.14 to 28.3 mA. Similarly, following 88 consecutive negative pulses, the device current changed, indicating long-term potentiation and long-term depression behaviors. We also employed a pair of continuous triangular wave pulses to evaluate paired-pulse facilitation behavior, observing that the response current of the second stimulus pulse was ∼1.2× greater than that of the first stimulus pulse. The advantages and prospects of using MoS2 as a material for thin-film transistors were thoroughly displayed. [ABSTRACT FROM AUTHOR]

A novel multilevel resistive switching was observed in epoxy methacrylate resin (EMAR) and carbon nanotubes (CNTs) composite films fabricated by spin coating method. The fabricated devices demonstrated the rewritable nonvolatile memory characteristics. More significantly, the memory device based on EMAR+CNTs composite exhibits multilevel stable conductivity states with stable intermediate resistance states in response to the applied voltage. By setting different compliance current and content of CNTs in composite film, the multilevel ON-states and even the multilevel OFF-states have been observed in our memory device. As fabricated devices exhibited multilevel resistive switching with stable resistance ratio between different resistance states having good data retention and endurance characteristics. It offers a novel design strategy for solution processable multilevel data storage. [ABSTRACT FROM AUTHOR]

The memory characteristic based on nonvolatile tuning behavior in indium tin oxide/poly( N -vinylcarbazole)/aluminum (ITO/PVK/Al) was investigated, the different memory behaviors were first observed in PVK film as the film thickness changing. By control of PVK film thickness with different spinning speeds, the nonvolatile behavior of ITO/PVK/Al sandwich structure can be tuned in a controlled manner. Obviously different nonvolatile behaviors, such as (i) flash memory behavior and (ii) write-once-read-many times (WORM) memory behavior are from the current–voltage ( I – V ) characteristics of the PVK films. The results suggest that the film thickness plays a key part in determining the memory type of the PVK. [ABSTRACT FROM AUTHOR]

Bistable nonvolatile memory devices with resistive switching characteristics were fabricated based on polyurethane (PU) doping with single-wall carbon nanotubes (SWCNTs). It has been demonstrated that the addition of SWCNTs in PU layer could enlarge the ON/OFF current ratio from 10 2 –10 4 and keep a long retention time over 9 h. Besides, the increase of SWCNTs and charge traps induced by SWCNT reduced the current in OFF state and enhanced the memory window significantly. Furthermore, the resistive switching behavior of indium tin oxide/PU + SWCNTs/aluminum device was attributed to the formation and breakdown of SWCNTs percolated network structure in the PU composites. [ABSTRACT FROM AUTHOR]

Bistable electrical switching and nonvolatile memory devices with the configuration of indium tin oxide (ITO)/active layer/aluminum (Al) are reported. The active layer were prepared from the mixed compositions of 2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole, (PBD) and poly( N -vinylcarbazole) (PVK). The as-fabricated ITO/PBD:PVK/Al sandwiched devices exhibited rewriteable flash memory property. Due to the strong interaction between oxadiazole acceptor and carbazole donor, the devices demonstrate excellent performance. The memory devices can operate over a small voltage range, the absolute value of switching-on threshold voltage is less than 1 V and the switching-off threshold voltage is less than 3.5 V. The ON/OFF ratio of current switches in the range of 10 4 –10 2 during the variation of applied voltage and the two different resistance states can be maintained over 4 h. [ABSTRACT FROM AUTHOR]

Two new Ru(II) complexes with 1,8-naphthalimide group, [Ru(phen) 2 (pnip)] 2 + (Ru 1 ; phen = 1,10-phenanthroline, pnip = 2-[ N -( p -phenyl)-1,8-napthalimide]imidazo[4',5'- f ][1,10]phenanthroline) and [Ru(bpy) 2 (pnip)] 2 + (Ru 2 ; bpy = 2,2′-bipyridine), have been synthesized and characterized. The interactions of Ru 1 and Ru 2 with the triplex RNA poly(U)•poly(A)*poly(U) (where • denotes the Watson–Crick base pairing and * denotes the Hoogsteen base pairing) were studied by various biophysical. Electronic spectra established that the binding affinity for Ru 1 was greater than that for Ru 2 . Fluorescence and viscosity studies gave convincing evidence for a true intercalative binding of both complexes with the RNA triplex. UV melting studies confirmed that the two complexes could stabilize the triplex, whereas the effects of the two complexes on the stability of the Hoogsteen base-paired strand ploy(U) and the Watson–Crick base-paired duplex poly(U)•poly(A) of the triplex were different. In the case of Ru 1 , the increase of the thermal stability of the Hoogsteen base-paired strand was stronger than that of the Watson–Crick base-paired duplex. However, an opposite effect was observed in the case of Ru 2 . Circular dichroic studies suggested that the RNA triplex undergoes a conformational transition in the presence of Ru 1 , whereas the helicity of the RNA triplex still remains A-type in the presence of Ru 2 . The main results obtained here further advance our knowledge on the interaction of RNA triple-stranded structures with metal complexes, particularly ruthenium(II) complexes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The asymmetric gate design was used to suppress the inherent ambipolarity of graphene. • Combined with chemically doped method to suppress the off state current of graphene transistors. • The on-state current is increased while the off-state current is effectively suppressed. • The on/off ratio is increased by nearly two orders of magnitude compared with the normal gate structure device. • Better threshold swing and smaller threshold voltage are obtained. Graphene is considered a promising transistor component for future integrated circuits. Due to high operating speed and low power consumption, high on/off ratio and low off state current are ideal transistors. However, due to the inherent ambipolarity of graphene, a significant ambipolarity behavior with a fairly high off state current is usually observed in graphene transistors. In this work, an asymmetric gate design combined with a chemically doped method to suppress the ambipolarity of graphene transistors was reported. Thus, the off-state current is effectively reduced and the on-state current is increased. The on/off ratio is increased by nearly two orders of magnitude. Compare to the normal gate structure device, better threshold swing and smaller threshold voltage are obtained. [ABSTRACT FROM AUTHOR]

Abstract: Large-scale membrane bioreactors (MBRs) have been widely used for the municipal wastewater treatment, whose performance relies on microbial communities of activated sludge. Nevertheless, microbial functional structures in MBRs remain little understood. To gain insight into functional genes and their steering environmental factors, we adopted GeoChip, a high-throughput microarray-based tool, to examine microbial genes in four large-scale, in-operation MBRs located in Beijing, China. The results revealed substantial microbial gene heterogeneity (43.7–85.1% overlaps) among different MBRs. Mantel tests indicated that microbial nutrient cycling genes were significantly (P < 0.05) correlated to influent COD, –N, TP or sulfate, which signified the importance of microbial mediation of wastewater constituent removal. In addition, functional genes shared by all four MBRs contained a large number of genes involved in antibiotics resistance, metal resistance and organic remediation, suggesting that they were required for degradation or resistance to toxic compounds in wastewater. The linkages between microbial functional structures and environmental variables were also unveiled by the finding of hydraulic retention time, influent COD, –N, mixed liquid temperature and humic substances as major factors shaping microbial communities. Together, the results presented demonstrate the utility of GeoChip-based microarray approach in examining microbial communities of wastewater treatment plants and provide insights into the forces driving important processes of element cycling. [Copyright &y& Elsevier]

Abstract: The long-term effect of set potential on oxygen reducing biocathodes was investigated in terms of electrochemical and biological characteristics. Three biocathodes were poised at 200, 60 and −100mV vs. saturated calomel electrode (SCE) for 110days, including the first 17days for startup. Electrochemical analyses showed that 60mV was the optimum potential during long-term operation. The performance of all the biocathodes kept increasing after startup, suggesting a period longer than startup time needed to make potential regulation more effective. The inherent characteristics without oxygen transfer limitation were studied. Different from short-term regulation, the amounts of biomass were similar while the specific electrochemical activity was significantly influenced by potential. Moreover, potential showed a strong selection for cathode bacteria. Clones 98% similar with an uncultured Bacteroidetes bacterium clone CG84 accounted for 75% to 80% of the sequences on the biocathodes that showed higher electrochemical activity (60 and −100mV). [Copyright &y& Elsevier]

Abstract: Four materials, carbon felt cube (CFC), granular graphite (GG), granular activated carbon (GAC) and granular semicoke (GS) were tested as packed anodic materials to seek a potentially practical material for microbial fuel cells (MFCs). The microbial community and its correlation with the electricity generation performance of MFCs were explored. The maximum power density was found in GAC, followed by CFC, GG and GS. In GAC and CFC packed MFCs, Geobacter was the dominating genus, while Azospira was the most populous group in GG. Results further indicated that GAC was the most favorable for Geobacter adherence and growth, and the maximum power densities had positive correlation with the total biomass and the relative abundance of Geobacter, but without apparent correlation with the microbial diversity. Due to the low content of Geobacter in GS, power generated in this system may be attributed to other microorganisms such as Synergistes, Bacteroidetes and Castellaniella. [Copyright &y& Elsevier]

[Display omitted] • Memristor based on Co-Ni LDHs hybrid nanosheets is reported. • Devices exhibit nonvolatile resistance switching behavior. • Multiple progressive resistance switches could be achieved. • Memristors were used to simulate synaptic function in biology. • O vacancy is the physical mechanism of the resistance switch behavior. Because of its excellent electrical properties and promising application prospects, two-dimensional materials have attracted extensive research interests of researchers. Among them, Co-Ni layered double hydroxide (LDH) has semiconductor properties and has been widely studied in super capacitor. However, there are few reports about 2D Co-Ni LDHs materials as memristors. In this work, a memristor based on Co-Ni LDHs hybrid nanosheets is reported. After electroforming, Al/Co-Ni LDHs/Al devices exhibit nonvolatile resistance switching behavior. More importantly, multiple progressive resistance switches could be achieved by adjusting the duration or amplitude of the applied pulse (less than the set threshold voltage to prevent a sudden setting process). Given its gradual resistive switching, Co-Ni LDHs-based memristors were used to simulate synaptic function in biology, including: "learning" and "forgetting" process, STP and LTP, PPF characteristics, and STDP. By studying the microstructure, it is proposed that the O vacancy is the physical mechanism of the resistance switch behavior. This work reveals that Co-Ni LDH nanosheets have excellent application potential in memristors, which may open the door to more functions and applications. [ABSTRACT FROM AUTHOR]

We research the transport properties on a three-region structure of the bulk Weyl semimetals. We show the change of electron scattering with field b 0 in center transport region when electrons pass through the center transport region. A valley is filtered when b 0 is near Fermi energy E F by calculating valley-resolved transmission probability and valley-resolved reflection probability of Weyl electrons. We also research the influence of short-range disorders on valley transport property. These results can not only contribute to the comprehending of Weyl semimetals and valleytronics, but also provide a feasible method to design valley filter in view of the Weyl semimetals. • The Weyl semimetals appear by adding perturbation to break inversion or time reversal symmetries in system, and the field b 0 and b z of perturbation can make Weyl points shift in energy E and momentum k. • The intervalley and intravalley scatterings with change of b 0 are calculated in the three-region structure, and one of the valleys can be filtered. • The influence of short-range disorders on valley transport property is researched. Due to the presence of short-range disorders, the transport channel of valley is affected. [ABSTRACT FROM AUTHOR]

• Threshold switching characteristics has been reported in 2D composite nanomaterials. • The effectiveness of cross crosstalk suppression was indicated by assembled 1S1R unit. • The developmental potentiality to restrain the crosstalk issue was indicated. 2D composite nanomaterials of insulating boron nitride (BN) and semiconductor molybdenum disulfide (MoS 2)-based flexible threshold switching selectors (Ag/BN+MoS 2 /Ag based on BM1 and BM2) are fabricated. Both selectors shown excellent bidirectional threshold switching characteristics. The assembled 1S1R unit comprising Ag/BN+MoS 2 /Ag based on BM1 selector and bipolar rewritable Ag/ZnO/Ag resistive switching memory shows the effectiveness of cross crosstalk suppression. The thermal conductivity of the functional layer based on BM2 decreasing to some extent with the content of BN decreasing, resulting in an increasing trend of V hold compared with selector based on BM1. And the selectors of Ag/BN+MoS 2 /Ag based on BM2 were assembled with a unidirectional open WORM Ag/polyvinyl carbazole/Ag memory, it also shows a good effect in restraining the crosstalk. It has large developmental potentiality in flexible 2D composite nanomaterials threshold switching selector to restrain the crosstalk issue for a large RRAM array. [ABSTRACT FROM AUTHOR]

We investigate the magneto-optical transport properties and Landau levels of type-II nodal line semimetals. The tilted liner dispersion in type-II nodal line semimetals makes the conduction band and valence band asymmetric, and Landau levels are coupling in the presence of a magnetic field. We find the background of absorption peaks is curved. The oscillation peaks are tailless with the change of magnetic field. Through tuning tilt term, we find the absorption peaks of optical conductivity change from incomplete degenerate structure to splitting double peaks structure. We also find interband absorption peaks is no longer zero in the imaginary part of Hall conductivity. With the change of the tilt term, the contribution of the absorption peak has two forms, one is that the negative peak only appears at high frequencies, and the other is two adjacent peaks with opposite signs. In addition, the resistivity, circularly polarized light and magnetic oscillation of Hall conductivity are studied. [ABSTRACT FROM AUTHOR]

• A layered materials memristor was introduced. • Memristors characteristic was modulated by hexazinone. • Gradual current changes were took on. • The memory device demonstrate programmable peculiarities. The nonvolatile resistive switching memory devices and the effect of adsorbed small molecule hexazinone have been investigated. Resistive switching behaviour of Co-Al layered double hydroxides (Co-Al LDHs)-based is gradually varied. At the same time, when Co-Al LDHs adsorbed the small molecule hexazinone, its resistive switching behaviour changed suddenly. Both memristors exhibit non-volatile data storage and good data retention characteristics. The influence of small molecule hexazinone on microcarrier transport was analyzed. This research manifests the promising potential of nanocomposite materials adsorbed electroactive small molecules in rectifying the resistive switching properties and provides some ideas for designing advanced devices of nanocomposite memristors. [ABSTRACT FROM AUTHOR]

A memory device based on MoS 2 -polyvinyl alcohol was fabricated. As a good dispersant, polyvinyl alcohol solution can disperse 2D layered materials more evenly in the solution. The 19 states of the device conductance are modulated step by step by direct current scanning, which makes it possible to perform the computing task in memory. Then, the presence of conductive filaments allows the resistance state of the memristor to be dynamically transformed, which is similar to some basic behavior of biological synapses. Further, a variety of conductivity states such as short-term potentiation, short term depression, long term potentiation and long-term depression behavior are modulated by applying voltage to simulate the basic behavior of biological synapses. Finally, the paired pulse facilitation, paired pulse depression, spiking timing dependent plasticity and spiking voltage dependent plasticity behaviors of biological synapses are simulated in memristor devices. [Display omitted] • A memory device based on MoS 2 and polyvinyl alcohol composite was fabricated. • The multi-states of the device conductance are modulated step by step. • The presence of conductive filaments allows the resistance state of the memristor to be dynamically transformed. • The basic behavior of biological synapses was simulated in memristor devices. [ABSTRACT FROM AUTHOR]

Predicting interactions between microbes and hosts plays critical roles in microbiome population genetics and microbial ecology and evolution. How to systematically characterize the sophisticated mechanisms and signal interplay between microbes and hosts is a significant challenge for global health risks. Identifying microbe-host interactions (MHIs) can not only provide helpful insights into their fundamental regulatory mechanisms, but also facilitate the development of targeted therapies for microbial infections. In recent years, computational methods have become an appealing alternative due to the high risk and cost of wet-lab experiments. Therefore, in this study, we utilized rich microbial metagenomic information to construct a novel heterogeneous microbial network (HMN)-based model named KGVHI to predict candidate microbes for target hosts. Specifically, KGVHI first built a HMN by integrating human proteins, viruses and pathogenic bacteria with their biological attributes. Then KGVHI adopted a knowledge graph embedding strategy to capture the global topological structure information of the whole network. A natural language processing algorithm is used to extract the local biological attribute information from the nodes in HMN. Finally, we combined the local and global information and fed it into a blended deep neural network (DNN) for training and prediction. Compared to state-of-the-art methods, the comprehensive experimental results show that our model can obtain excellent results on the corresponding three MHI datasets. Furthermore, we also conducted two pathogenic bacteria case studies to further indicate that KGVHI has excellent predictive capabilities for potential MHI pairs. [ABSTRACT FROM AUTHOR]