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The main purpose of this paper is to consider the multiple birth properties for multi-type Markov branching processes. We first construct a new multi-dimensional Markov process based on the multi-type Markov branching process, which can reveal the multiple birth characteristics. Then the joint probability distribution of multiple birth of multi-type Markov branching process until any time t is obtained by using the new process. Furthermore, the probability distribution of multiple birth until the extinction of the process is also given. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced silicon carbide matrix composites (Cf/SiC composites) are lightweight, high strength, wear-resistant, and heat-resistant, making them widely used in aerospace and other industries. However, machining holes in Cf/SiC composites is a great challenge due to the anisotropy and high hardness of the material. In this paper, a brazed diamond grinding rod was employed to grind 1 mm diameter holes in Cf/SiC composites, and the influence of grinding parameters on grinding force, hole entrance/exit defects, and hole wall quality was investigated. In addition, the material removal mechanism of Cf/SiC composites and the wear mechanism of the diamond grinding rod were explored. The findings showed that the damage at the hole entrance and exit predominantly manifests as tearing and burring. The damage factor at the hole exit is 3.5% larger than that at the hole entrance, and the damage factor at both the hole entrance and exit reduces with the growth of spindle speed and the decrease of feed rate. In addition, the diameter errors of the hole entrances and exits are all less than 10%, and the entrance diameter is 2.9% larger than the exit. The hole wall defects include fiber fracture, silicon carbide matrix peeling, and inherent porosity, with poorer surface quality at fiber orientation angles (FOA) of 90° to 180°. The main wear mechanisms were identified as abrasive wear and the spalling of abrasive grains. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important pathogens affecting the swine industry. In this report, a novel PRRSV strain SXht2012 was isolated from Shanxi province in China. To identify genetic characteristics of SXht2012, we conducted phylogenetic and homology analyses after sequencing its complete genome. The results revealed that SXht2012 belonged to NADC30-like strain and shared 91.3% nucleotide (nt) identity with strain NADC30. Notably, sequence alignment showed that a distinctive feature in the NSP2 region, where a 131-amino acid (aa) deletion was found in the hypervariable region (HVR). Additionally, variations were also detected in the GP5 protein, specifically in the decoy peptide, T cell peptide, and a potential glycosylation site (aa 32). Furthermore, we also found that SXht2012 was likely a recombination virus originating from NADC30-like and JXA1-like strains, and three recombination breakpoints were identified in the genome at nt positions 1516, 5280 and 6851, which correspond to the NSP2, NSP3, and NSP7 regions. Overall, these findings have significant implications for understanding the genetic variation and evolutionary dynamics of PRRSV strains. [ABSTRACT FROM AUTHOR]

Let { X t ; t ≥ 0 } be a Markov branching process with immigration, in which each particle has exponential lifetime distribution with parameter a and offspring law { p k ; k = 0 , 1 , 2 , ... } . The time interval of immigration follows an exponential distribution with parameter θ . Let p 0 = 0 and λ : = a (∑ k = 1 ∞ k p k - 1) < ∞ . In this paper, we investigate the large deviation behavior of X t + s / X t ; t ≥ 0 , s > 0 by studying the asymptotic behavior of harmonic moments E [ X t - r ] for r > 0 . We obtain that there is a "phase transition" in rates depending on whether λ r - a - θ is less than, equal to or greater than 0. [ABSTRACT FROM AUTHOR]

The hybrid aerial underwater vehicle (HAUV) could operate in the air and underwater might provide a great convenience for aerial and underwater exploration, and the fixed-wing HAUV (FHAUV) has time, space and cost advantages in future large-scale applications, while the large difference between the aerial and underwater environments is a challenge to control, especially in the air/water transition. However, for FHAUV control, there is a lack of research on phenomena or problems caused by large changes in the air/water transition. In addition, the effects of wind, wave, other factors and conditions on motion control are not investigated. This paper presents the first control study on the above issues. The motion model of FHAUV is developed, with the effects of wind and wave disturbances. Then, this paper improves a cascade gain scheduling (CGS) PID for different media environments (air and water) and proposes a cascade state feedback (CSF) control strategy to address the convergence problem of FHAUV control caused by large speed change in the air/water transition. In the comparisons of the two control schemes in various tracking cases including trajectory slopes, reference speeds, wind and wave disturbances, CSF has a better control effect, convergence rate and robustness; the key factors and conditions of the air/water transition are investigated, the critical relations and feasible domains of the trajectory slopes and reference speeds that the FHAUV must meet to successfully exit the water and enter the air are obtained, the critical slope decreases as the reference speed increases, and the feasible domain of CSF is larger than that of CGS, revealing that CSF is superior than CGS for exiting the water. [ABSTRACT FROM AUTHOR]

Based on the resolvent decomposition theorems presented very recently by Chen (J Theor Probab 33:2089–2118, 2020), in this paper we focus on investigating the fundamental problems of existence and uniqueness criteria for Denumerable Markov Processes with finitely many instantaneous states. Some elegant sufficient and necessary conditions are obtained for this less-investigated topic. A few important examples including the generalized Kolmogorov models are presented to illustrate our general results. [ABSTRACT FROM AUTHOR]

In this paper, we consider n-type Markov branching–immigration processes. The uniqueness criterion is first established. Then, we construct a related system of differential equations based on the branching property. Furthermore, the explicit expression of extinction probability and the mean extinction time are successfully obtained in the absorbing case by using the unique solution of the related system of differential equations and Kolmogorov forward equations. Finally, the recurrence and ergodicity criteria are given if the zero state 0 is not absorbing. [ABSTRACT FROM AUTHOR]

This study aimed to explore the occurrence of necroptosis in skeletal muscle after eccentric exercise and investigate the role and possible mechanisms of ZBP1 and its related pathway proteins in the process, providing a theoretical basis for the study of exercise-induced skeletal muscle injury and recovery. Forty-eight male adult Sprague–Dawley rats were randomly divided into a control group (C, n = 8) and an exercise group (E, n = 40). The exercise group was further divided into 0 h (E0), 12 h (E12), 24 h (E24), 48 h (E48), and 72 h (E72) after exercise, with 8 rats in each subgroup. At each time point, gastrocnemius muscle was collected under general anesthesia. The expression levels of ZBP1 and its related pathway proteins were assessed using Western blot analysis. The colocalization of pathway proteins was examined using immunofluorescence staining. After 48 h of eccentric exercise, the expression of necroptosis marker protein MLKL reached its peak (P < 0.01), and the protein levels of ZBP1, RIPK3, and HMGB1 also peaked (P < 0.01). At 48 h post high-load eccentric exercise, there was a significant increase in colocalization of ZBP1/RIPK3 pathway proteins, reaching a peak (P < 0.01). (1) Eccentric exercise induced necroptosis in skeletal muscle, with MLKL, p-MLKLS358, and HMGB1 significantly elevated, especially at 48 h after exercise. (2) After eccentric exercise, the ZBP1/RIPK3-related pathway proteins ZBP1, RIPK3, and p-RIPK3S232 were significantly elevated, particularly at 48 h after exercise. (3) Following high-load eccentric exercise, there was a significant increase in the colocalization of ZBP1/RIPK3 pathway proteins, with a particularly pronounced elevation observed at 48 h post-exercise. [ABSTRACT FROM AUTHOR]

In order to improve the oxidation resistance of SiC/SiC composites, four types of modified SiC/SiC composites were fabricated by PIP method using polyborosilazane and/or polycarbosilane precursor. The order to use polyborosilazane and polycarbosilane precursor during PIP process plays a key role to affect the oxidation resistance of composites. The SiC/SiBCN-SiC composites reveals the highest oxidation resistance. The SiC matrix outside the SiBCN matrix can effectively inhibit the volatilization of liquid B2O3 at 1200 °C. Liquid B2O3 filled the micro-cracks of matrix during the oxidation process, which prevent further oxidation damages. Micro-cracks in the matrix of SiC/SiBCN and SiC/SiC-SiBCN composites cannot be sealed due to the volatilization of liquid B2O3 at 1200 °C, leading to higher oxidation damages in the composites. [ABSTRACT FROM AUTHOR]

To observe whether downhill running can lead to DNA damage in skeletal muscle cells and changes in mitochondrial membrane permeability and to explore whether the DNA damage caused by downhill running can lead to changes in mitochondrial membrane permeability by regulating the components of the endoplasmic reticulum mitochondrial coupling structure (MAM). A total of 48 male adult Sprague–Dawley rats were randomly divided into a control group (C, n = 8) and a motor group (E, n = 40). Rats in Group E were further divided into 0 h (E0), 12 h (E12), 24 h (E24), 48 h (E48) and 72 h (E72) after prescribed exercise, with 8 rats in each group. At each time point, flounder muscle was collected under general anaesthesia. The DNA oxidative damage marker 8-hydroxydeoxyguanosine (8-OHdG) was detected by immunofluorescence. The expression levels of the DNA damage-related protein p53 in the nucleus and the EI24 protein and reep1 protein in whole cells were detected by Western blot. The colocalization coefficients of the endoplasmic reticulum protein EI24 and the mitochondrial protein Vdac2 were determined by immunofluorescence double staining, and the concentration of Ca2+ in skeletal muscle mitochondria was detected by a fluorescent probe. Finally, the opening of the mitochondrial membrane permeability transition pore (mPTP) was detected by immunofluorescence. Twelve hours after downhill running, the mitochondrial membrane permeability of the mPTP opened the most (P < 0.05), the content of 8-OHdG in skeletal muscle peaked (P < 0.05), and the levels of the regulatory protein p53, mitochondrial Ca2+, and the EI24 and reep1 proteins peaked (P < 0.01). Moreover, the colocalization coefficients of EI24 and Vdac2 and the Mandes coefficients of the two proteins increased first and then recovered 72 h after exercise (P < 0.05). (1) Downhill running can lead to DNA damage in skeletal muscle cells, overload of mitochondrial Ca2+ and large opening of membrane permeability transformation pores. (2) The DNA damage caused by downhill running may result in p53 promoting the transcriptional activation of reep1 and EI24, enhancing the interaction between EI24 and Vdac2, and then leading to an increase in Ca2+ in skeletal muscle mitochondria and the opening of membrane permeability transition pores. [ABSTRACT FROM AUTHOR]

This paper presents the design and control method of the hybrid underwater glider (HUG) for hands-on investigative engineering. The HUG is a lightweight, small, modular, and low-cost underwater vehicle. The HUG uses a piston buoyancy system to control buoyancy and pitch angle and two thrusters to control yaw angle. A hybrid control method utilizing both a piston buoyancy system and a pair of horizontal thrusters is proposed. The novelty of this study is: 1) a two-hull design to facilitate modularity and ease of assembly, 2) an effective piston buoyancy and thrusters’ mechanism to reduce the weight and size of the vehicle, and 3) a pitch control method based on equilibrium identification to enables a fixable and convenient parameters selection and reduces model dependence. Experimental results show that the HUG design reduces the thrusters’ disturbance to pitch angle control, and pitch angle control with the hybrid control method has less overshoot compared to the PID controller. [ABSTRACT FROM AUTHOR]

We consider the important decay parameter issue for a Markovian bulk-arrival and bulk-service queue which stops at reaching the first m states. The results obtained in this paper are a significant generalization of the ones obtained in Chen et al. (Queueing Syst 66:275–311, 2010). The exact value of the decay parameter is obtained. Based on the results obtained in this paper, we provide a practical method for calculating the decay parameter which is very effective. In some cases, the decay parameter can even be easily expressed explicitly. Some important key lemmas which also have their own interest are provided. The interesting and clear geometric interpretation of the decay parameter is explained. A few examples are provided to illustrate the results obtained in this paper. [ABSTRACT FROM AUTHOR]

This paper concentrates on considering the down/up crossing property of weighted Markov collision processes. The joint probability generating function of down crossing and up crossing numbers of weighted Markov collision processes until its extinction are obtained by constructing and studying a related multi-dimensional Markov chain. Hence, the joint probability distribution of down crossing and up crossing numbers and the mean numbers are obtained. [ABSTRACT FROM AUTHOR]

Let { X n } 0 ∞ be a supercritical branching process with immigration with offspring distribution { p j } 0 ∞ and immigration distribution { h i } 0 ∞. Throughout this paper, we assume that p 0 = 0 , p j ≠ 1 for any j ≥ 1 , 1 < m = ∑ j = 0 ∞ j p j < ∞ , and h 0 < 1 , 0 < a = ∑ j = 0 ∞ j h j < ∞. We first show that Y n = m - n (X n - m n + 1 - 1 m - 1 a) is a martingale and converges to a random variable Y. Secondly, we study the rates of convergence to 0 as n → ∞ of P (Y n - Y > ε) , P X n + 1 X n - m > ε | Y ≥ α for ε > 0 and α > 0 under various moment conditions on { p j } 0 ∞ and { h i } 0 ∞. It is shown that the rates are always supergeometric under a finite moment generating function hypothesis. [ABSTRACT FROM AUTHOR]

Let {X(t);t ≥ 0} be a continuous-time branching-immigration system with branching rates {bk; k ≥ 0,k≠ 1} and immigration rates {ak; k ≥ 1}. We assume that b0 = 0, m = : ∑ k = 1 ∞ k b k < ∞ and a = : ∑ k = 1 ∞ k a k < ∞ . In this paper, we first discuss the martingale property of W(t) = e−mtX(t) − m− 1a(1 − e−mt) and prove that it has a limit W. Furthermore, we show that X(t + s)/X(t) converges to ems in probability, W(t) converges to W in probability and X(t + s)/X(t) converges to ems in probability conditioned on W ≥ α (here α is a positive constant) as t → ∞ . The explicit estimates of the above three convergence rates are obtained under various moment conditions on {bk; k ≥ 0,k≠ 1}. It is shown that the rate of the first one is geometric, while the other two are supergeometric. [ABSTRACT FROM AUTHOR]

We consider the regularity and ergodic properties of the Branching Collision Process with Immigration (BCIP) in this paper. We establish an easy checking sufficient condition under which the Feller minimal BCIP is honest. We provide some good conditions under which the Feller minimal BCIP is positive recurrent and then establish an analytic form of the generating function of the stationary distribution. The closely associated expected hitting times are also considered. Examples and numerical calculations are provided to illustrate our results. [ABSTRACT FROM AUTHOR]

In this paper, 1-mm-thickness monomer cast nylon 6 sheets were joined under the pressure and the frictional heat generated between the pinless tool and thin stainless steel plates, which was named friction spot pressure welding technology. Influences of welding parameters on spot weld diameter, morphology, and mechanical performance were investigated. Results showed that incomplete interfacial bonding was observed under insufficient plunge depth. Increased rotational speed, plunge depth, and dwell time caused severer extrusion ring and reticular cracks on the joint surface. Material overheating occurred under rotational speed of 1000 rpm and material adhesion on the back of steel plate happened under plunge depth of 0.25 mm. The weld-bonded area diameter increased with larger welding parameters, but the corresponding joint fracture loads increased and then decreased. Four failure modes including lap interface tearing (IT), upper sheet fracture (UF), outer bonding area separation (BS), and the mixed UF and BS were observed. Spot welds failed with UF possessed the maximum tensile load while joints fractured with IT showed low performance. Three different morphologies were observed on the fracture surface of the IT joints while the fracture surfaces of the joints failed with other fracture modes showed elongated strips and flocculent structures. [ABSTRACT FROM AUTHOR]

Two undescribed phenolic compounds, angelicols A (1) and B (2) and one undescribed coumarin rhamnoside, angelicoside A (3), together with 17 known compounds (4–20) were isolated from the roots of Angelica dahurica. Their structures were characterized by physical data analyses such as NMR, HRESIMS, and X-ray diffraction. Compounds 2, 3, 5, 6 and L-ascorbic acid (positive control) exhibited obvious DPPH radical scavenging activities with IC50 values of 0.36 mM, 0.43 mM, 0.39 mM, 0.44 mM, 0.25 mM, respectively. At a concentration of 25 μM, all compounds showed weaker tyrosinase inhibition activities (%inhibition < 5%) than kojic acid (26.00 ± 0.67%, IC50 = 44.29 ± 0.06 μM). [ABSTRACT FROM AUTHOR]

One novel neoligan glucoside, Ginkgoside B (1), and one new glucose ester, 6-O-(4-hydroxyhydrocinnamoyl)-d-glucopyranose (2), along with nine known compounds (3–11) were isolated from the ethanol extract of Ginkgo biloba leaves. Their structures were elucidated by combination of spectroscopic analyses and alkaline methanolysis. The absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. All the isolated compounds were evaluated for their cytotoxicity activities, and compound 11 exhibited IC50 values of 36.20 and 58.95 μM against 5637 and HeLa cell lines, respectively. [ABSTRACT FROM AUTHOR]

In this paper, friction plug welding technology was employed to join Acrylonitrile Butadiene Styrene sheets. Proper welding process was investigated and determined first, and the influence of plug diameter and length, blind hole profile and depth on joint morphology and mechanical performance was investigated subsequently. Results showed that incomplete connection was generated at the weld boundary when no chuck was utilized, and excellent bonding was produced with the employment of a chuck. Joints produced with blind holes that characterized by perpendicular base angle showed incomplete fusion at the bottom corner of the weld while defect-free joints were obtained with rounded hole base angle. Plug size and blind hole depth significantly affected the joint morphology and strength. Cavities were formed under small plug diameter, excessive plug length or large blind hole depth, and weak connection occurred when plug length was small. Joint shear strength increased with the plug diameter but decreased with the plug length. Proper increase of the hole depth slightly influenced the joint quality, but extreme hole depth caused reduced joint strength. Only joints fabricated with insufficient plug length failed with lower nugget pulling out and other spot welds failed with shear fracture. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of a new correction method (inverted “V” release surgery) for epicanthus as a cause of congenital entropion/trichiasis in the lower eyelid.Methods: From May 2014 to May 2017, 60 eyes of 30 patients (13 male and 17 female patients, with the age of 6.85 ± 4.52 years underwent inverted “V” release surgery to correct epicanthus. The incision in the epicanthus and entropion was continuous. Lower eyelid entropion/trichiasis was corrected by a two-layered suture. We separately assessed the width of the palpebral fissure, exposed ratio of the lacrimal caruncle, eyelash direction, and incision scar at one and 6 months after surgery.Results: All patients were followed up for 6-18 months. At 6 months after surgery, the palpebral fissure width of all patients was extended by 3-4 mm. The ratio of the exposed lacrimal caruncle was enhanced from 0.24 ± 0.22 to 0.75 ± 0.08. All patients presented with natural inner canthal angles, and their eyelashes clearly extended outward, with a 100% total effective rate. The inner canthal incision scars in 83% of patients were invisible 6 months after surgery.Conclusion: Based on our experience, both functionality and aesthetics can be obtained by using inverted “V” release surgery to correct a special type of epicanthus that aggravates congenital entropion/trichiasis in the lower eyelid. Thus, this technique is suitable for clinical application.Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]

In this paper, pinless tool was utilized in the friction stir spot welding (FSSW) of acrylonitrile butadiene styrene (ABS) sheets. ABS gaskets were added to the through-hole of the clamping plate before FSSW in order to avoid upper sheet thickness reduction. The influence of different combinations of plunge rate (PR) and gasket thickness (GT) on joint morphology and mechanical behavior was investigated. Results showed that low PR and GT caused incomplete connection at the center of the bonded area, and straight and sound bonding interface was formed under the moderate PR and GT. Apparent material flow occurred in the vicinity of the lap interface when PR and GT were large. With the increase of PR and GT, bonded area diameter enlarged while joint fracture load increased first and then slightly decreased. Joints produced with and without thickness reduction failed with different fracture modes, and the removing of upper sheet thickness reduction was beneficial to the promotion of the joint strength. [ABSTRACT FROM AUTHOR]

A loose coupling method is adopted to study electromagnetic tube bulging, and effect of processing parameters on electromagnetic tube bulging is analyzed. The results show that critical relative length increases with the increasing of coil length, when coil approaches infinite length, critical length approximates 1. With the rise of relative position, radial magnetic pressure acting on the top end of tube increases, when relative position is equal or greater than 30 mm, radial magnetic pressure of tube top end remains unvaried. Relative position of 30-50 mm is optimal position for electromagnetic tube flanging. [ABSTRACT FROM AUTHOR]

We consider a very general interacting branching process which includes most of the important interacting branching models considered so far. After obtaining some key preliminary results, we first obtain some elegant conditions regarding regularity and uniqueness. Then the extinction vector is obtained which is very easy to be calculated. The mean extinction time and the conditional mean extinction time are revealed. The mean explosion time and the total mean life time of the processes are also investigated and resolved. [ABSTRACT FROM AUTHOR]

We consider an M / M/ c queue with catastrophes and state-dependent control at idle time. Properties of the queues which terminate when the servers become idle are first studied. Recurrence, equilibrium distribution, and equilibrium queue-size structure are studied for the case of resurrection and no catastrophes. All of these properties and the first effective catastrophe occurrence time are then investigated for the case of resurrection and catastrophes. In particular, we obtain the Laplace transform of the transition probability for the absorbing M / M/ c queue. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a serious microvascular complication of diabetes mellitus that is closely associated with the degeneration and loss of retinal ganglion cells (RGCs) caused by diabetic microangiopathy and subsequent oxidative stress and an inflammatory response. Microglial cells are classed as neurogliocytes and play a significant role in neurodegenerative diseases. Over-activated microglial cells may cause neurotoxicity and induce the death and apoptosis of RGCs. Crocin is one of the two most pharmacologically bioactive constituents in saffron. In the present study, we focused on the role of microglial cells in DR, suggesting that DR may cause the over-activation of microglial cells and induce oxidative stress and the release of pro-inflammatory factors. Microglial cells BV-2 and N9 were cultured, and high-glucose (HG) and free fatty acid (FFA) were used to simulate diabetes. The results showed that HG-FFA co-treatment caused the up-regulated expression of CD11b and Iba-1, indicating that BV-2 and N9 cells were over-activated. Moreover, oxidative stress markers and pro-inflammatory factors were significantly enhanced by HG-FFA treatment. We found that crocin prevented the oxidative stress and pro-inflammatory response induced by HG-FFA co-treatment. Moreover, using the PI3K/Akt inhibitor LY294002, we revealed that PI3K/Akt signaling plays a significant role in blocking oxidative stress, suppressing the pro-inflammatory response, and maintaining the neuroprotective effects of crocin. In total, these results provide a new insight into DR and DR-induced oxidative stress and the inflammatory response, which provide a potential therapeutic target for neuronal damage, vision loss, and other DR-induced complications. [ABSTRACT FROM AUTHOR]

H9 subtype avian influenza viruses (AIVs) remain a significant burden in the poultry industry and are considered to be one of the most likely causes of any new influenza pandemic in humans. As ducks play an important role in the maintenance of H9 viruses in nature, successful control of the spread of H9 AIVs in ducks will have significant beneficial effects on public health. Duck enteritis virus (DEV) may be a promising candidate viral vector for aquatic poultry vaccination. In this study, we constructed a recombinant DEV, rDEV-∆UL2-HA, inserting the hemagglutinin (HA) gene from duck-origin H9N2 AIV into the UL2 gene by homologous recombination. One-step growth analyses showed that the HA gene insertion had no effect on viral replication and suggested that the UL2 gene was nonessential for virus growth in vitro. In vivo tests further showed that the insertion of the HA gene in place of the UL2 gene did not affect the immunogenicity of the virus. Moreover, a single dose of 10 TCID of rDEV-∆UL2-HA induced solid protection against lethal DEV challenge and completely prevented H9N2 AIV viral shedding. To our knowledge, this is the first report of a DEV-vectored vaccine providing robust protection against both DEV and H9N2 AIV virus infections in ducks. [ABSTRACT FROM AUTHOR]

This paper deals with a predator-prey model of Beddington-DeAngelis type functional response with Lévy jumps. The proposed mathematical model consists of a system of two stochastic differential equations to stimulate the interactions between predator population and prey population. The dynamics of the system is discussed mainly from the point of view of persistence and extinction. To begin with, the global positivity, stochastically boundedness and other asymptotic properties have been derived. In addition, sufficient conditions for extinction, nonpersistence in the mean and weak persistence are obtained. It is proved that the variation of Lévy jumps can affect the asymptotic property of the system. [ABSTRACT FROM AUTHOR]

This paper deals with stochastic nonautonomous Gompertz model with Lévy jumps. To begin with, the existence of a global positive solution and an explicit solution have been derived. In addition, asymptotic moment properties are discussed. Besides, sufficient conditions for extinction, persistence in mean, and weak persistence are obtained. It is proved that the variability of Lévy jumps can affect the asymptotic property of the system. [ABSTRACT FROM AUTHOR]

Ras homology GTPase activation protein 6 (Arhgap6), as a member of the rhoGAP family of proteins, performs vital functions on the regulation of actin polymerization at the plasma membrane during several cellular processes. The role of Arhgap6 in the progression and development of cancer remains nearly unknown. This study aimed at exploring the effects of Arhgap6 on cervical carcinoma. Human cervical cancer cells HeLa and SiHa were transduced with a lentivirus targeting Arhgap6 (Arhgap6+), while CaSki and C4-1 cells were transfected with miRNA. Cell proliferation was identified by Cell Counting Kit-8 (CCK-8). Cell cycle distribution and cell apoptosis were identified by flow cytometry. The capacity of cell migration, invasion, and adhesion were detected by Transwell assay. Further, quantitative real-time PCR (qRT-PCR) and western blot were used to analyze the expression levels of Arhgap6 and several tumor-related genes. Co-immunoprecipitation assay was performed to validate the interaction between Arhgap6 and Rac3 (Ras-related C3 botulinum toxin substrate 3). Results showed that Arhgap6 inhibited cell proliferation, migration, invasion, and adhesion of cervical carcinoma, induced cell apoptosis, and caused cell cycle arrest in the G0/G1 phase ( n = 3, p < 0.05). Expression of the tumor suppressor genes and oncogenes were up- and down-regulated respectively by Arhgap6, and Rac3 was proved to be the target of Arhgap6. Besides, in in vivo assays, tumor size and weight were destructed in Arhgap6+ athymic nude mouse. This study indicated that Arhgap6 may play a role in the treatment of cervical cancer as a tumor supressor. [ABSTRACT FROM AUTHOR]

Previous studies focusing on identification of dietary risk factors for hyperuricemia reported controversial findings. Moreover, evidence for relationship between hyperuricemia and eating and cooking habits remained scanty. The purpose of this study was to evaluate the associations between hyperuricemia and dietary risk factors. A cross-sectional study was conducted among 1583 participants in a Beijing community. Face-to-face interviews were conducted using questionnaires. Anthropometric measurements and biochemical tests were also performed. The prevalence of hyperuricemia was 14.1 % (20.2 % for males and 7.4 % for females). Among the 1372 subjects included for analysis, 720 (52.5 %) were males and the mean age was 37.7 years. For males, statistically significant associations between hyperuricemia and tea intake, breakfast and midnight snack consumption were found, with an odds ratio of 0.56 (high vs. low), 2.14 (often vs. always) and 0.52 (rarely vs. always), respectively. Smoking, fatty liver disease, triglyceride, low-density lipoprotein cholesterol and fasting blood glucose were significantly related to increased serum uric acid (SUA), with a coefficient of 20.06, 11.52, 7.29, 18.97 and 13.37 on SUA, respectively. For females, no statistically significant associations between hyperuricemia and dietary risk factors were observed. In summary, hyperuricemia is highly prevalent among the adult participants in this Chinese community, especially for men. High tea intake and consuming midnight snack rarely are significantly related to decreased risk of hyperuricemia, while often-eating breakfast is associated with increased risk of hyperuricemia compared with always-eating breakfast in males. Further prospective studies are needed to confirm the findings and to establish dietary recommendations for the prevention and treatment of hyperuricemia. [ABSTRACT FROM AUTHOR]

Bluetongue virus (BTV) is the causative agent of bluetongue (BT), an important sheep disease that caused great economic loss to the sheep industry. There are 26 BTV serotypes based on the outer protein VP2. However, the serotypes BTV-1 and BTV-16 are the two most prevalent serotypes in China. Vaccination is the most effective method of preventing viral infections. Therefore, the need for an effective vaccine against BTV is urgent. In this study, DNA vaccines and recombinant fowlpox virus (rFPV) vaccines expressing VP2 alone or VP2 in combination with VP5 or co-expressing the VP2 and VP5 proteins of BTV-1 were evaluated in both mice and sheep. Several strategies were tested in mice, including DNA vaccine prime and boost, rFPV vaccine prime and boost, and DNA vaccine prime and rFPV vaccine boost. We then determined the best vaccine strategy in sheep. Our results indicated that a strategy combining a DNA vaccine prime (co-expressing VP2 and VP5) followed by an rFPV vaccine boost (co-expressing VP2 and VP5) induced a high titer of neutralizing antibodies in sheep. Therefore, our data suggest that a DNA vaccine consisting of a pCAG-(VP2+VP5) prime and an rFPV-(VP2+VP5) boost is an important candidate for the design of a novel vaccine against BTV-1. [ABSTRACT FROM AUTHOR]

Bluetongue virus (BTV) is the etiological agent of bluetongue (BT) disease, a noncontagious insect-transmitted disease of international importance. To date, 26 BTV serotypes have been recognized worldwide. Methods to discriminate BTV serotypes in clinical samples are essential to epidemiological surveillance efforts and BTV vaccination programs. The BTV VP2 major outer capsid protein, encoded by genomic segment 2 (Seg-2), is the most highly variable BTV protein and is the primary determinant of the virus serotype. Here, we report the development of rapid and reliable real-time RT-PCR assays to detect and discriminate 22 BTV serotypes on the basis of VP2-encoding genomic sequences. Serotype-specific primers and probes detected only the targeted BTV serotype and displayed no cross-amplification of off-target BTV serotypes or other closely related Reoviridae and Bunyaviridae family members. The real-time RT-PCR assays developed were highly sensitive, and the majority of serotype-specific reactions could detect template when present at ≥10 copies. These BTV serotype-specific real-time RT-PCR assays represent a rapid, sensitive, and reliable method for the identification, differentiation and quantification of 22 BTV serotypes. [ABSTRACT FROM AUTHOR]

We consider a multiclass service system with refusal and bulk-arrival. The properties regarding recurrence, ergodicity, and decay properties of such model are discussed. The explicit criteria regarding recurrence and ergodicity are obtained. The stationary distribution is given in the ergodic case. Then, the exact value of the decay parameter, denoted by λ, is obtained in the transient case. The criteria for the λ-recurrence are also obtained. Finally, the corresponding λ-invariant vector/measure is considered. [ABSTRACT FROM AUTHOR]

Ionic liquid-based ultrasonic-assisted extraction (IL-UAE) was successfully developed to extract the known phenolics gallic acid, chlorogenic acid, rutin, psoralen, and bergapten present in the leaves, pulps, and peels of Ficus carica L. In this work, the proposed method was evaluated in comparison with regular ultrasonic-assisted extraction in which methanol was the extractant and exhibited higher efficiency. Moreover, ionic liquids with different cations were investigated and 1-butyl-3-methylimidazole hexafluorophosphate solution was selected as the optimal extractant at concentration of 1.0 mol L. The corresponding extraction parameters including extraction solvent, the concentration of [BMIM][PF], solid-liquid ratio (g mL), ultrasonic extraction time, and extraction temperature were optimized. The phenolics were then determined by high-performance liquid chromatography (HPLC). Under the optimized conditions, the content of gallic acid, chlorogenic acid, rutin, psoralen, and bergapten in leaves, pulps, and peels of F. carica L. was 12.67-37.16, 14.75-90.07, 107.91-222.37, 2.59-67.83, and 1.99-20.21 μg/0.1 g, respectively. This study suggests that IL-UAE is a rapid, simple, and green preparation technique. [ABSTRACT FROM AUTHOR]

The FeO-FeO nanocomposites were prepared by the co-precipitation method and followed by calcination process. The products were synthesized and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray analysis. The obtained FeO-FeO nanocomposites were then applied to study the electrocatalytic reduction of hydrogen peroxide (HO) in 0.01 M pH 7.0 phosphate buffer medium. Then the FeO-FeO nanocomposites were used as active electrode material of electrochemical sensors for HO detection The detection sensitivity of the sensor was 20.325 μA mM , and the detection limit was estimated to be about 0.2 mM. [ABSTRACT FROM AUTHOR]

To gain a better understanding of the genetic changes required for attenuation of duck enteritis virus (DEV), the Chinese standard challenge strain of DEV (DEV CSC) was serially passaged 80 times in chick embryo fibroblasts. We plaque-purified the virus after the 25th passage (DEV p25) and the 80th passage (DEV p80) and investigated its in vitro and in vivo properties. Average plaque sizes for DEV p25 and p80 were significantly smaller than those for their parental DEV CSC. The results from an in vivo experiment revealed that DEV p25 and p80 were avirulent in ducks and protected them from virulent DEV challenge. The complete genome sequence of DEV p80 was determined and compared with that of the parent virus. An 1801-bp deletion was identified in the genome of DEV p80, which affected the genes encoding gI and gE. Moreover, there were 11 base substitutions, which led to seven amino acid changes in open reading frames LORF9, UL51, UL9, UL7, UL4, ICP4 and US3. Further DNA sequence analysis showed that the 1801-bp deletion was also present in DEV p25. Our findings suggest that DEV gE and/or gI are nonessential for virus growth and might, as with other herpesviruses, play an important role in cell-to-cell spread and virulence. Our experiments provide more genetic information about DEV attenuation and further advance our understanding of the molecular basis of DEV pathogenesis. [ABSTRACT FROM AUTHOR]

We consider decay properties regarding decay parameter and invariant measures of Markovian bulk-arrival and bulk-service queues with state-independent control. The exact value of the decay parameter, denoted by λ, is firstly revealed. A criterion regarding λ-recurrence and λ-positive is obtained. The corresponding λ-subinvariant/invariant measures and λ-subinvariant/invariant vectors are then presented. [ABSTRACT FROM AUTHOR]

Here, we present the complete genomic sequence of the Chinese standard challenge strain (CSC) of duck enteritis virus (DEV), which was isolated in China in 1962. The DEV CSC genome is 162,131 bp long and contains 78 predicted open reading frames (ORFs). Comparison of the genomic sequences of DEV CSC and DEV live vaccine strain K at passage 63 (DEV K p63) revealed that the DEV CSC genome is 4,040 bp longer than the DEV K p63 genome, mainly because of 3,513-bp and 528-bp insertions at the 5′ and 3′ ends of the unique long segment, respectively. At the nucleotide level, 63 of the 76 ORFs in the DEV CSC genome were 100 % identical to the ORFs in the DEV K p63 genome. Two ORFs (UL56 and US10) had frameshift mutations in the C-terminal regions, while LORF5 was unique to the DEV K p63 genome. It is difficult to assign attenuated virulence to changes in specific genes. However, the complete DEV CSC genome will further advance our understanding of the genes involved in virulence and evolution. The DEV CSC genome sequence has been deposited in GenBank under accession number JQ673560. [ABSTRACT FROM AUTHOR]

In this paper, the approximate controllability of fractional impulsive neutral stochastic differential equations with nonlocal conditions and infinite delay in Hilbert spaces is studied. By using the Krasnoselskii-Schaefer-type fixed point theorem and stochastic analysis theory, some sufficient conditions are given for the approximate controllability of the system. At the end, an example is given to illustrate the application of our result. MSC: 65C30, 93B05, 34K40, 34K45. [ABSTRACT FROM AUTHOR]

We consider decay properties including the decay parameter, invariant measures, invariant vectors, and quasistationary distributions for n-type Markov branching processes on the basis of the 1-type Markov branching processes and 2-type Markov branching processes. Investigating such behavior is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for n-type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λ of such model is given for the communicating class C = ℤ \ 0. It is shown that this λ can be directly obtained from the generating functions of the corresponding q-matrix. Moreover, the λ-invariant measures/vectors and quasidistributions of such processes are deeply considered. λ-invariant measures and quasi-stationary distributions for the process on C are presented. [ABSTRACT FROM AUTHOR]

We consider the Markov branching process with immigration allowing the possibility of infinite numbers of offspring and/or immigrants. Our focus is on the construction and uniqueness of the minimal transition function and on its asymptotic behavior. Conditional limit theorems for the population size are given in cases for which the transition function is dishonest. [ABSTRACT FROM AUTHOR]

Purpose: To determine the presence of integrin-linked kinase (ILK) in tissue samples of retinoblastoma patients, and to explore the function of ILK in human Y79 retinoblastoma cells. Methods: The expression of ILK was studied in samples of retinoblastoma patients by immunohistochemistry. In vitro, specific small interfering RNA (siRNA) targeting ILK was transfected into Y79 retinoblastoma cells using liposome. Silencing of ILK expression was measured by reverse transcription-polymerase chain reaction (RT-PCR), real-time PCR and Western blotting assays. Then the regulation of cell proliferation and apoptosis was assessed by Cell Counting Kit-8(CCK-8), Annexin V-FITC/ propidium iodide (PI) immunofluorescence, and flow cytometry assays. Furthermore, the involvement of c-Jun N-terminal kinase signal pathway was tested by JNK signal transduction inhibitor assay. Results: Positive staining for ILK was detected in 15 of the 17 retinoblastoma tissue samples. Specific siRNA targeting ILK significantly silenced ILK expression in Y79 retinoblastoma cells, as confirmed by RT-PCR, real-time PCR and Western blotting assays ( P < 0.01). This was accompanied by decreased cell proliferation ( P < 0.05) and enhanced apoptosis ( P < 0.01). The phosphorylation status of JNK and c-Jun was constitutively activated by ILK siRNA ( P < 0.01), and JNK inhibitor simultaneously reversed the effects on cell proliferation and apoptosis induced by ILK siRNA. Conclusion: Our results demonstrated that ILK promoted proliferation and suppressed apoptosis via repressing phosphorylations of the JNK signal pathway in human retinoblastoma cells. This might provide a potential therapeutic target in the treatment of this deadly disease. [ABSTRACT FROM AUTHOR]

We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly investigated in detail. The explicit expressions for the extinction probabilities and mean extinction times are presented. The ergodicity and stability properties of the process incorporating with resurrection structure are then investigated. The conditions for recurrence, ergodicity and exponential ergodicity are obtained. An explicit expression for the equilibrium distribution is also presented. As a preparation, the criteria for regularity and uniqueness for such structure are firstly established. [ABSTRACT FROM AUTHOR]

To achieve a ZrO-B-C ternary solid-state reaction, a small amount of carbon was introduced into a binary system of ZrO and boron. Amorphous hydrous ZrO precursor was firstly prepared through precipitation method using zirconyl nitrate and ammonia at room temperature. Then, ZrB powder was successfully synthesized using the as-prepared amorphous hydrous nano-ZrO via borothermal and carbothermal reduction (BCTR) by amorphous boron and nanocarbon powders under flowing argon. Plate-like ZrB particles with a uniform distribution and ca. 1.0 μm in two-dimensions were obtained with a B/Zr molar ratio of 4, and 5 wt.% (total weight of dry hydrous ZrO and boron) nanocarbon at 1550 °C for 2 h. [ABSTRACT FROM AUTHOR]

We consider decay properties including the decay parameter, invariant measures and quasi-stationary distributions for a Markovian bulk-arrival and bulk-service queue which stops when the waiting line is empty. Investigating such a model is crucial for understanding the busy period and other related properties of the Markovian bulk-arrival and bulk-service queuing processes. The exact value of the decay parameter λ is first obtained. We show that the decay parameter can be easily expressed explicitly. The invariant measures and quasi-distributions are then revealed. We show that there exists a family of invariant measures indexed by λ∈[0, λ]. We then show that under some mild conditions there exists a family of quasi-stationary distributions also indexed by λ∈[0, λ]. The generating functions of these invariant measures and quasi-stationary distributions are presented. We further show that this stopped Markovian bulk-arrival and bulk-service queueing model is always λ-transient. Some deep properties regarding λ-transience are examined and revealed. The clear geometric interpretation of the decay parameter is explained. A few examples are then provided to illustrate the results obtained in this paper. [ABSTRACT FROM AUTHOR]