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•The Young's moduli of both λ-Cu2Se and ζ-Cu2Se increase gradually as the number of layers increases.•The Poisson's ratios of both λ-Cu2Se and ζ-Cu2Se are thickness independent.•The band gaps of both λ-Cu2Se and ζ-Cu2Se decrease with increasing thickness.•The absorption coefficients increase gradually for both λ-Cu2Se and ζ-Cu2Se from ML to bulk.

•Graphene/XAg4Y (X, Y = S, Se, and Te) possess different graphene/X interface, resulting in various Schottky barrier heights and contact types.•Schottky barrier heights and contact types can be modulated by the vertical strain and external electric field.•The mechanism of the tunable Schottky barrier via the vertical strain and external electric field are investigated.•Vertical strain or external electric field underlies that the relative Dirac-cone position of graphene in heterostructures can be tuned.

ABSTRACTAntimicrobial acroautophagy/autophagy plays a vital role in degrading intracellular pathogens or microbial molecules in host-microbe interactions. However, microbes evolved various mechanisms to hijack or modulate autophagy to escape elimination. Vector-transmitted phloem-limited bacteria, CandidatusLiberibacter (Ca. Liberibacter) species, cause Huanglongbing (HLB), one of the most catastrophic citrus diseases worldwide, yet contributions of autophagy to HLB disease proliferation remain poorly defined. Here, we report the identification of a virulence effector in “Ca. Liberibacter asiaticus” (Las), SDE3, which is highly conserved among the “Ca. Liberibacter”. SDE3expression not only promotes the disease development of HLB and canker in sweet orange (Citrus sinensis) plants but also facilitates Phytophthoraand viral infections in Arabidopsis, and Nicotiana benthamiana(N.benthamiana). SDE3 directly associates with citrus cytosolic glyceraldehyde-3-phosphate dehydrogenases (CsGAPCs), which negatively regulates plant immunity. Overexpression of CsGAPCsand SDE3significantly inhibits autophagy in citrus, Arabidopsis, and N.benthamiana. Intriguingly, SDE3 undermines autophagy-mediated immunity by the specific degradation of CsATG8 family proteins in a CsGAPC1-dependent manner. CsATG8 degradation is largely rescued by treatment with an inhibitor of the late autophagic pathway, E64d. Furthermore, ectopic expression of CsATG8senhances Phytophthoraresistance. Collectively, these results suggest that SDE3-CsGAPC interactions modulate CsATG8-mediated autophagy to enhance Las progression in citrus.Abbreviations:ACP: asian citrus psyllid; ACD2: ACCELERATED CELL DEATH 2; ATG: autophagy related; Ca. Liberibacter: CandidatusLiberibacter; CaMV: cauliflower mosaic virus; CMV: cucumber mosaic virus; Cs: Citrus sinensis; EV: empty vector; GAPC: cytosolic glyceraldehyde-3-phosphate dehydrogenase; HLB: huanglongbing; H2O2: hydrogen peroxide; Las: liberibacter asiaticus; Laf: liberibacter africanus; Lam: liberibacter americanus; Pst: Pseudomonas syringaepv. tomato; PVX: potato virus X; ROS: reactive oxygen species; SDE3: sec-delivered effector 3; TEM: transmission electron microscopy; VIVE : virus-induced virulence effector; WT: wild-type; Xcc: Xanthomonas citrisubsp. citri;

Two-dimensional (2D) transition metal chalcogenides have garnered significant research interest owing to their novel properties and potential applications. In this paper, we report a novel class of group-11 chalcogenide MX (M = Cu, Ag, Au; X = S, Se, Te) monolayers based on first-principles calculations, which demonstrate significant application potential as polarized metals and visible-light-driven photo-catalysts. ι-CuS, ι-AgS ι-AgTe, η-CuSe, and η-CuTe were found to be metals, while β-AgSe, α-AuS, α-AuSe, and α-AuTe were observed to be semiconductors with a bandgap of 1.46, 2.14, 1.77, and 1.37 eV respectively. Interestingly, the work functions of the bottom and top sides of ι-CuS, ι-AgS, and ι-AgTe differed owing to the out-of-plane inversion asymmetry of the ι phase. Moreover, these metallic MX monolayers were used to form graphene-based metal-metal heterostructures; accordingly, the work function of graphene could be modulated from 4.35 eV to the range of 3.87–5.04 eV. For semiconducting MX monolayers, a-phase and β-phase monolayers just satisfied the band edge requirement for the H+/H2and H2O/O2reaction at pH 0/7, respectively. Further investigations on the α-AuSe/α-AuTe heterostructure demonstrated its great application potential as a Z-scheme photocatalyst in visible-light-driven overall water splitting with appropriate band alignment, enhanced optical absorbance and high solar-to-hydrogen energy conversion efficiency (20.47%). Benefitting from these excellent properties, 2D group-11 chalcogenide MX monolayers can be potentially used as polarized metals and visible-light-driven water splitting photocatalysts.

Objective Auriculocondylar syndrome (ARCND) is a set of rare craniofacial malformations characterized by variable micrognathia, ear malformations, and mandibular condyle hypoplasia, and other accompanying features with phenotypic complexity. ARCND2 caused by pathogenic variants in the PLCB4gene is a very rare disease with less than 50 patients reported and only 36 different variants of the PLCB4gene recorded in HGMD. This study aims to enrich the patient resources, clinical data and mutational spectrum of ARCND2.Design Case series study.Setting Guangzhou Women and Children's Medical Center and Guangdong Women and Children Hospital.Patients Two Chinese patients with ARCND2.Main Outcome Measures Clinical, radiological and molecular findings.Results Both the two patients presented with craniofacial and ear malformations, and feeding difficulties. Whole exome sequencing identified two different variants of the PLCB4gene in these two patients with a heterozygous allele and a de novomode of inheritance respectively. Patient 1 carried a known pathogenic c.1861C > T(p.Arg621Cys) missense variant, whereas Patient 2 had a novel c.225 + 1G > A splicing variant. Sanger sequencing confirmed the presence of PLCB4variants in the proband and absence in the unaffected parents. These two PLCB4variants were suggested as disease-causing candidates for these two patients. During a 5-year follow-up, Patient 2 gradually manifested crowded teeth, underweight, motor delay and intellectual disability.Conclusions In this study, we report two Chinese patients with ARCND2, describe their clinical and mutational features, and share a 5-year follow-up of one patient. Our study adds two additional patients to ARCND2, reveals a novel PLCB4variant, and expands the phenotypic and genotypic spectrum.

•Au2Te is mechanically stable and has excellent mechanical flexibility.•The highly anisotropic mechanical, electronic and optical properties indicate that it can be applied to direction-sensitive sensors.•The band gaps can be effectively tuned by uniaxial and biaxial strain.•The optical absorbances and TDM are more sensitive to biaxial strain.

In this paper, we investigate the effects of time delay and non-Gaussian noise on the dynamics properties of the attractor network model of perceptual bistability. Using delay Fokker–Planck equation and projection operator method, the stationary probability distribution Pst(x), the associated relaxation time Tc, and the normalized correlation function C(s) for perceptual bistability are obtained, respectively. Research results show that: (i) the time delay τand the correlation time τ0 from non-Gaussian noise can induce the change of the peaks in the Pst(x), i.e., the phase transition of the system appears; (ii) there exhibits an optimal value of the τ0 or τby which the Tc or C(s) is maximum, this maximum shows the τ0 or τfirst reduces the stability of the attractor network model of perceptual bistability in the steady state, and then enhances it; and (iii) the noise intensity P or departure q from the Gaussian noise only enhances the stability of the attractor network model of perceptual bistability in the steady state.

The dislocation widths, Peierls barriers and Peierls stresses for shuffle screw dislocations in diamond structure crystals, Si and Ge, have been calculated by the improved P-N theory. The widths are about 0.6b, where b is the Burgers vector. The Peierls barrier for shuffle screw dislocation in Si and Ge, is about 3.61~4.61meV/Å and 5.31~13.32meV/Å, respectively. The Peierls stress is about 0.28~0.33GPa and 0.31~0.53GPa, respectively. The calculated Peierls barriers and stresses are likely the results of shuffle screw dislocation with metastable core which is centered on the bond between two atoms.

Abstract: In this paper, we investigate the escape of Brownian particles and stochastic resonance (SR) with low-temperatures quantum fluctuations by using the quantum Smoluchowski equations at low-temperature. Two specific examples have been considered: one is the example of bistable system, and the other is the example of metastable system. The explicit expressions of the mean-first passage time (MFPT) and signal-to-noise ratio (SNR) for both specific examples are obtained, respectively. Based on the numerical computations, we compare the quantum case with its classical counterpart. Our research results show that: (i) the quantum effect accelerates the escape of the Brownian particle in comparison with the classical result and (ii) the quantum effect enhances the SR in the SNR as a function of β for a bistable system (i.e., β = 1/k B T, k B is the Boltzmann constant and T is the temperature), while for a metastable system, the β amplifies the quantum effects, and the quantum effect weakens the SNR as a function of β.

Chalcogenide perovskite materials have received extensive attention in the field of thermoelectrics (TEs) due to their inherent large Seebeck coefficient and ultra-low thermal conductivity. Herein, we demonstrate that the orthorhombic CaZrS3perovskite is a promising TE material by using first-principles calculations combined with the semiclassical Boltzmann transport theory. The anisotropic property has been observed clearly on the electronic properties and TE performances of CaZrS3along a, b, and cdirections. The orthorhombic CaZrS3shows excellent thermal stability, which leads to superior performance of electric and thermal conductivities simultaneously; thus it possesses outstanding power factor and ultra-low thermal conductivity and yields impressive ZT values of n-4.06 and p-2.62. This study provides a guideline for chemical doping and provides inspiration for the promotion of related experimental investigations.

• The stability of tumor-immune responses to chemotherapy system with Gaussian white noises is researched. • The upper Lyapunov exponents of linearized system with Gaussian white noises are computed. • The related conclusions give reference value for the effect of chemotherapy. The stability of tumor-immune responses to chemotherapy system driven by Gaussian white noises is researched because noises can have an important role in tumor treatment. In this system, there are several steady states. In order to explore the stability of these steady states, the upper Lyapunov exponents of linearized system in these steady states are computed by means of second-order algorithm for stochastic simulation Gaussian white noises. The results show that, one steady state is globally asymptotical stable if and only if the noises are weak, but another steady state is always unstable whether the noise is strong or weak. Moreover, the trajectory of system evolution initiating from anywhere is simulated by same algorithm, which proves preceding conclusions and exhibits the globally asymptotical stable steady state is a sink when noises are weak. In fact, the related conclusions give reference value for the effect of chemotherapy on tumor treatment. [ABSTRACT FROM AUTHOR]

We consider an inertial Brownian particle moving in a symmetric periodic potential which is subjected to an unbiased time-periodic force combined with a constant static force and the fluctuant generated by a dichotomous noise. For the deterministic case, there are multiple current reversals as the mass increases, which would imply the phenomena of negative mass and mobility. A physical explanation of these phenomena is derived from basins of attraction. For the case of an additional random mass, the results show that the system may be very sensitive to a small change of the strength of dichotomous noise. An increase of the strength of dichotomous noise leads not only to significant decrease of the intervals of negative mass but also to shrinking the regions of negative mobility or even vanishing it. The probability distribution of the Brownian particle' velocity is used to interpret the underlying mechanisms. We also study diffusion corresponding to these mobilities in the system. It is found that the negative mass and mobility can strengthen the diffusion. Our findings may extensively exist in physical, chemical, and material fields, which provides a way to manipulate the mobility of Brownian particle by altering the strength of dichotomous noise. [ABSTRACT FROM AUTHOR]

The effect of non-Gaussian noise on the coherent feed-forward loop with time delay is researched. Based on delayed Fokker–Planck equation, the expressions of the steady-state probability distribution, mean, normalized variance, normalized skewness, and normalized kurtosis of concentration variables y and z of two transcription factors X, Y and a target gene Z in the model are derived. Then, the impacts of the noise intensity D , parameter q indicating the departure from Gaussian noise, correlation time τ 0 of non-Gaussian noise, and time delay τ on the steady-state probability distribution, mean, normalized variance, skewness, and kurtosis are discussed. The results show that, non-Gaussian noise will weaken the stability of Y and Z , increase the concentration of y and z , and ultimately benefit the output of target gene Z. Time delay also weaken the stability of Y and Z , but increase the concentrations of y and decrease the concentrations of z , i.e., suppress the output of target gene Z. In addition, numerical simulations are performed and consistent with approximate theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the stochastic kinetics in a time-delayed foraging colony system under non-Gaussian noise were investigated. Using delay Fokker–Planck approach, the stationary probability distribution (SPD), the normalized variance β 2 , skewness β 3 and kurtosis β 4 of the state variable are obtained, respectively. The effects of the time delayed feedback and non-Gaussian noise on the SPD are analyzed theoretically. The numerical simulations about the SPD are obtained and in good agreement with the approximate theoretical results. Furthermore, the impacts of the time delayed feedback and non-Gaussian noise on the β 2 , β 3 and β 4 are discussed, respectively. It is found that the curves in β 2 , β 3 and β 4 exhibit an optimum strength of feedback where β 2 , β 3 and β 4 have a maximum. This maximum indicates the large deviations in β 2 , β 3 and β 4 . From the above findings, it is easy for us to have a further understanding of the roles of the time delayed feedback and non-Gaussian noise in the foraging colonies system. [ABSTRACT FROM AUTHOR]

In this paper, stationary probability distribution (SPD), mean first passage time (MFPT) and stochastic resonance (SR) phenomenon of an abstract model of the Myc/E2F/MiR-17-92 network with time delay and cross-correlation noise sources are investigated. The impacts of time delay τ , additive and multiplicative noise intensities Q and D , and cross-correlation intensity λ between noises on the SPD, MFPT, and SNR are discussed, respectively. Research results show that: (i) the high protein level (or ON) state is enhanced (or weaken) by the τ (or λ ); (ii) the MFPT as a function of Q or D exhibits a maximum, which is the signature of the noise enhanced stability (NES) of the ON state. The stability of the ON state can also enhance (or weaken) by the λ (or τ ); (iii) the existence of a maximum and a minimum in the signal-to-noise ratio (SNR) is identifying the characteristics of the SR and stochastic reverse-resonance (SRR) phenomenon, τ and λ enhance the SR and weaken the SRR phenomenon for SNR as a function of Q , while τ (or λ ) weakens (or enhances) the SR phenomenon for SNR as a function of D ; and (iv) the time delay weakens the SR, and causes the SR phenomenon to disappear for SNR as a function of λ . [ABSTRACT FROM AUTHOR]

We numerically investigate the transport properties and dynamic relaxation of a classical inertia Brownian particle in a biased periodic potential under the action of friction and thermal fluctuations. The both fluctuations may be related to friction, thus they may be correlated with each other. We mainly focus on how particle's transport and dynamic relaxation are affected by fluctuations and the correlation between them. It is unexpected that the combinations of them can tune transport of the particle, including current reversal, and anomalous mobility and diffusions. These results are explained via the stationary probability distributions, which suggest that the bias of the potential can lead to a transition between unimodal and bimodal stationary probability distributions of particle's velocity. To understand the physical mechanism of these findings, we present dynamic relaxations, namely, the transient probability distributions of velocity and position. These distributions suggest that the motion of the particle is not only related to systematic parameters, but also sensitive to the initial conditions. Our findings may be potentially helpful for research on various transport of the particle and on similar circuits, such as particle separation, Josephson junctions, the phase-locked loops, etc. [ABSTRACT FROM AUTHOR]