In this work, the Riemann–Hilbert (RH) problem is employed to study the multiple high-order pole solutions of the cubic Camassa–Holm (cCH) equation with the term characterizing the effect of linear dispersion under zero boundary conditions and nonzero boundary conditions. Under the reflectionless situation, we generalize the residue theorem and obtain the multiple high-order pole solutions of cCH equation by solving an algebraic system. During the process of establishing the solution of RH problem, to simplify the calculations involving the implicitly expressed of variables (x, t) in the solution, we introduce a new scale (y, t) to ensure the solution of RH problem is explicitly expressed with respect to it. Finally, the exact solutions are obtained for cases involving one high-order pole and N high-order poles.

Time preference reversal refers to systematic inconsistencies between preferences and bids for intertemporal options. From the two eye-tracking studies (N1 = 60, N2 = 110), we examined the underlying mechanisms of time preference reversal. We replicated the reversal effect in which individuals facing a pair of intertemporal options choose the smaller-sooner option but assign a higher value to the larger-later one. Results revealed that the mean fixation duration and the proportion of gaze time on the outcome attribute varied across the choice and bid tasks. In addition, time preference reversals correlated with individual differences in maximizing tendencies. Findings support the contingent weighting hypothesis and strategy compatibility hypothesis and allow for improved theoretical understanding of the potential mechanisms and processes involved in time preference reversals.

Two new genera and six new species of trilobites are systematically documented herein: Sinagnostus mirabilis new genus new species, Yanpingia punctata n. gen. n. sp., Illaenus taoyuanensis n. sp., Panderia striolatus n. sp., Nileus yichongqiaoensis n. sp., and Paratiresias peculiaris n. sp. The materials were collected from the Darriwilian (late Middle Ordovician) strata in the Upper Yangtze Region, South China. Also provided is an emended diagnosis of the genus Paratiresias based on the new species Paratiresias peculiaris, which is the oldest known species of this genus with an extremely narrow (sag. and exsag.) preglabellar field. Those Chinese species previously referred to Nanillaenus are reassigned to Illaenus sensu lato. These trilobites add new data for the Darriwilian trilobite macroevolution and show highly endemic to South China and the faunal exchanges between South China and Tarim, Kazakhstan, Alborz, as well as Sibumasu and North China.

UUID: http://zoobank.org/ec3be9be-b003-4367-910d-7a0ac4edc982

Partial differential equations (PDEs) are used with huge success to model phenomena across all scientific and engineering disciplines. However, across an equally wide swath, there exist situations in which PDEs fail to adequately model observed phenomena, or are not the best available model for that purpose. On the other hand, in many situations, nonlocal models that account for interaction occurring at a distance have been shown to more faithfully and effectively model observed phenomena that involve possible singularities and other anomalies. In this article we consider a generic nonlocal model, beginning with a short review of its definition, the properties of its solution, its mathematical analysis and of specific concrete examples. We then provide extensive discussions about numerical methods, including finite element, finite difference and spectral methods, for determining approximate solutions of the nonlocal models considered. In that discussion, we pay particular attention to a special class of nonlocal models that are the most widely studied in the literature, namely those involving fractional derivatives. The article ends with brief considerations of several modelling and algorithmic extensions, which serve to show the wide applicability of nonlocal modelling.

This investigation addresses the dynamics of annular viscoelastic films flowing down a flexible tube. The fluid viscoelasticity is assumed to be weak in order to obtain approximate explicit expressions for the stresses. Based on Shkadov’s integral boundary layer method (Fluid Dyn., vol. 2(1), 1967, pp. 29–34), a set of nonlinear evolution equations is derived that is valid for flows with moderate Reynolds numbers. The linear stability property of the system is examined by using normal-mode analysis, which is verified by comparing the results with those resulting from the linearization of the full Navier–Stokes equations. The results indicate that the fluid viscoelasticity plays an unstable role in the stability of the annular film flow. The tube flexibility, which includes wall damping and wall tension, plays a dual role. A bifurcation analysis is performed, and the families of steady travelling waves are catalogued. It is found that the stiffness of the tube tends to stimulate the interfacial capillary ripples. The fluid viscoelasticity acts to strengthen the dispersion of the interfacial waves but weakens the interfacial capillary ripples. The spatio-temporal evolutions of the system are also solved numerically. When the tube radius is small enough, tube closure can be observed due to the Plateau–Rayleigh instability. The fluid viscoelasticity acts to promote tube closure while the tube radius is relatively small. However, it plays a role in postponing the closure of the tube with a large radius.

Recent evidence shows that excess nicotinamide can cause epigenetic changes in developing rats. The aim of the present study was to investigate the effects of maternal nicotinamide supplementation on the fetus. Female rats were randomised into four groups fed a standard chow diet (control group) or diets supplemented with 1 g/kg of nicotinamide (low-dose group), 4 g/kg of nicotinamide (high-dose group) or 4 g/kg of nicotinamide plus 2 g/kg of betaine (betaine group) for 14–16 d before mating and throughout the study. Fetal tissue samples were collected on the 20th day of pregnancy. Compared with the control group, the high-dose group had a higher fetal death rate, and the average fetal body weight was higher in the low-dose group but lower in the high-dose group. Nicotinamide supplementation led to a decrease in placental and fetal hepatic genomic DNA methylation and genomic uracil contents (a factor modifying DNA for diversity) in the placenta and fetal liver and brain, which could be completely or partially prevented by betaine. Moreover, nicotinamide supplementation induced tissue-specific alterations in the mRNA expression of the genes encoding nicotinamide N-methyltransferase, DNA methyltransferase 1, catalase and tumour protein p53 in the placenta and fetal liver. High-dose nicotinamide supplementation increased fetal hepatic α-fetoprotein mRNA level, which was prevented by betaine supplementation. It is concluded that maternal nicotinamide supplementation can induce changes in fetal epigenetic modification and DNA base composition. The present study raises the concern that maternal nicotinamide supplementation may play a role in the development of epigenetic-related diseases in the offspring.

Cryopreservation can cause cumulus cell damage around the immature oocytes, which may result in poor subsequent development. To evaluate the effect of the meiosis stage on the cumulus cell cryoinjury and determine the suitable stage for cryopreservation in immature oocytes, mouse oocytes at germinal vesicle (GV) and germinal vesicle breakdown (GVBD) stages were vitrified using open pulled straw (OPS) method. Cumulus cells damage was scored immediately after thawing by double-fluorescent staining. The survival rate of the oocytes was evaluated and the subsequent development of oocytes was assessed through in vitro culture (IVC) and in vitro fertilization (IVF) separately. After vitrification, a higher proportion of cumulus cells of GV oocytes were damaged than those of GVBD and untreated control groups. The survival rate of vitrified GVBD oocytes (94.1%) was significantly higher (p < 0.05) than that of GV oocytes (85.4%). Oocytes vitrified at GVBD stage (55.7%) showed similar cleavage rate compared to those at GV stage (49.2%), but significantly higher (p < 0.05) blastocyst rate (40.9% vs. 27.4%). These results demonstrate that oocytes at GVBD stage remain better cumulus membrane integrity and developmental ability during vitrification than those at GV stage, indicating they are more suitable for immature oocytes cryopreservation in mice.

Tyrosinase (TYR) is a key enzyme of melanin biosynthesis. Single-strand conformation polymorphism (SSCP) analysis was applied to detect the single nucleotide polymorphisms (SNPs) in the upstream regulating region from -641 to -2125 bp of the TYR gene. Three SNPs were found in this region. Correlations were obtained between genotypes of the SNP sites and pigment traits in chicken parental and F2 generations of the Chinese Agricultural University (CAU) resource population. The chi-square test indicated that these mutations were significantly related to shank and body skin colours.