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The research follows the mainstream physics and network system architecture. Aiming at the problem of poor data processing ability and poor robustness of traditional trajectory detection algorithms...

Zinc-finger Y is located in the short arm of the Y-chromosome and is a highly conserved gene that plays an important role in spermatogenesis. The objective of this study was to investigate the influence of silencing the Zfy gene during spermatogenesis on Y-sperm formation and offspring sex determination in Bos taurus cattle. Three recombinant expression vectors pLL3.7/a, pLL3.7/b and pLL3.7/c were evaluated and only pLL3.7/a effectively silenced the Zfy gene. The pLL3.7/a recombinant expression vector was injected into bull testes, using three injections. Semen was collected and preserved by extending and freezing. The frozen semen was subsequently used in artificial insemination of cows during a breeding season in accordance with the production plan on the farm where the experiment was conducted. Results showed that, after exposure to pLL3.7/a, sperm motility decreased (P 0.01), but the sperm density was similar (p 0.05) to the non-treated control semen. Injection of pLL3.7/a resulted in 72.0% female offspring, and was greater than the 49.4% female calves in the control (P ＜ 0.01), Results from this research suggests that the Zfy gene plays a role in the process of Y-sperm formation, and Zfy siRNA is a potential useful approach to control sex of offspring in cattle.

Cystic echinococcosis, caused by infection with the larval stage of the cestode Echinococcus granulosus, is a chronic zoonosis. The lifecycle of the E. granulosus parasite includes three consecutive stages that require specific gene regulation or protein expression to survive environmental shifts between definitive hosts and intermediate hosts. The aim of the present study is to screen and analyze the stage differential antigens to be considered for vaccine development against E. granulosus. By using the iTRAQ (isobaric tags for relative and absolute quantification) method, the differentially expressed proteins were selected from the three consecutive developmental stages of E. granulosus: oncosphere, adult tapeworms, and protoscolex. Through a bioinformatics analysis including Clusters of Orthologous Groups (COG), Gene Ontology (GO), and pathway metabolic annotation, we identified some proteins of interest from each stage. The results showed that a large number of differentially expressed proteins (375: oncosphere vs. adult, 346: oncosphere vs. protoscolex, and 391: adult vs. protoscolex) were identified from the three main lifecycle stages. Analysis of the differential protein pathways showed that these differential proteins are mainly enriched in metabolic pathways, Huntington's diseases, Alzheimer's diseases, and ribosome metabolic pathways. Interestingly, among these differential proteins, expression levels of paramyosin, HSP60, HSP70, HSP90, cathepsin L1, cathepsin D, casein kinase, and calmodulin were significantly higher in the oncosphere than in the adult or protoscolex (p 0.05). We hope our findings will help to identify potential targets for diagnosis or for therapeutic and prophylactic intervention.Analyse protéomique comparative basée sur iTRAQ de différents stades de développement d’Echinococcus granulosus.L’échinococcose kystique, causée par une infection au stade larvaire du cestode Echinococcus granulosus, est une zoonose chronique. Le cycle de vie du parasite E. granulosus comprend trois étapes consécutives qui nécessitent une régulation génétique ou une expression de protéines spécifiques pour survivre aux changements environnementaux entre les hôtes définitifs et les hôtes intermédiaires. Le but de la présente étude est de cribler et d’analyser les antigènes différentiels de stade à considérer pour le développement de vaccins contre E. granulosus. En utilisant la méthode iTRAQ (étiquettes isobares pour la quantification relative et absolue), les protéines différentiellement exprimées ont été sélectionnées parmi les trois stades de développement consécutifs d’E. granulosus : l’oncosphère, les ténias adultes et le protoscolex. Grâce à une analyse bioinformatique comprenant les grappes de groupes orthologues (COG), l’ontologie des gènes (GO) et l’annotation des voies métaboliques, nous avons identifié certaines protéines d’intérêt à chaque étape. Les résultats ont montré qu’un grand nombre de protéines exprimées différentiellement (375 : oncosphère vs adulte, 346 : oncosphère vs protoscolex et 391 : adulte vs protoscolex) sont identifiées pour les trois étapes principales du cycle de vie. L’analyse des voies différentielles des protéines a montré que ces protéines différentielles sont principalement enrichies dans les voies métaboliques, la maladie de Huntington, la maladie d’Alzheimer et les voies métaboliques des ribosomes. Fait intéressant, parmi ces protéines différentielles, les niveaux d’expression des protéines paramyosine, HSP60, HSP70, HSP90, cathepsine L1, cathepsine D, caséine kinase et calmoduline étaient significativement plus élevés dans l’oncosphère que chez l’adulte ou le protoscolex (p 0,05). Nous espérons que nos résultats pourront identifier des cibles potentielles pour un diagnostic ou une intervention thérapeutique ou prophylactique.

In this study, membrane electrode assemblies (MEAs) were fabricated using a simultaneous electrospinning/electrospraying (E/E) technique to produce a unique nanoparticle/nanofiber cathode catalyst layer morphology evidenced by scanning electron microscopy. H2/O2 and H2/air polymer electrolyte membrane fuel cell performance was evaluated for E/E MEAs at ultra-low Pt cathode loadings of 0.052 and 0.022 mgPt cm−2, where maximum power densities of 1.090 and 0.936 W cm−2 (H2/O2) and 0.656 and 0.625 W cm−2 (H2/air) were achieved at these two Pt loadings, respectively. This was compared to a conventional control MEA at a 0.42 mgPt cm−2 cathode catalyst loading with maximum power densities of 1.420 and 0.839 W cm−2 for H2/O2 and H2/air, respectively. These results correspond to a significant reduction in Pt loading (5–12% of control) at only a modest reduction in power density (∼66–78% of control) for the E/E electrodes. Excellent platinum utilization in the cathode of 0.024 gPt kW−1 (∼42 kW gPt−1) was achieved for the E/E electrode at 0.022 mgPt cm−2 cathode loading. Cyclic voltammetry results show an electrochemical surface area higher in the E/E electrodes compared to the control, which provides a rationale for the excellent platinum utilization results, where the E/E morphology results in more triple phase boundaries with more accessible Pt in the electrode.

In this study, catalyst layers (CLs) were fabricated using a simultaneous electrospinning/electrospraying (E/E) technique to produce unique nanofiber/nanoparticle membrane electrolyte assemblies (E/E MEAs) evidenced by scanning electron microscopy. Specifically, the effect of polytetrafluoroethylene (PTFE) in these E/E MEAs on polymer electrolyte membrane (PEM) fuel cell performance was evaluated. E/E MEAs result in high fuel cell performance at ultra-low platinum (Pt) loadings with higher electrochemical surface areas as evidenced by cyclic voltammetry experiments. Without PTFE, an E/E MEA operated at 172 kPa (25 psi) back pressure results in a maximum power density of 1.090 W/cm2 (H2/O2) and 0.647 W/cm2 (H2/air) with only 0.112 mgPt/cm2 total Pt MEA loading. Introducing PTFE (at only 1 wt%) to the electrospinning process results in an E/E MEA operated at the same back pressure (172 kPa (25 psi)) with an even higher maximum power density of 1.240 W/cm2 (H2/O2) and 0.725 W/cm2 (H2/air) at a lower total Pt MEA loading of 0.094 mgPt/cm2. This corresponds to a significant reduction in Pt loading (16% of control) with only a modest reduction in power density (∼86-87% of control), where the control MEA was produced using a conventional coating method and resulted in maximum power density of 1.420 W/cm2 (H2/O2) and 0.839 W/cm2 (H2/air) at a Pt MEA loading of 0.570 mgPt/cm2 (172 kPa (25 psi)). An excellent total MEA platinum utilization of 0.076 gPt/kW (∼13.2 kW/gPt) was achieved with the E/E MEA with PTFE at only a 0.094 mgPt/cm2 total Pt MEA loading. The improvement in E/E MEA with PTFE was a result of increased hydrophobicity of the nanofibers evidenced by contact angle measurements and improved PEM fuel cell performance at higher limiting current density in the mass transport region.

The objective of this study was to explore a novel method to alter the sex-ratio balance of mouse offspring by silencing the paralogous genes Zfx/Zfy (Zinc finger X/Y-chromosomal transcription factor gene) during spermatogenesis. Four recombined vectors PRZ1, PRZ2, PRZ3, and PRZ4 (RNAi-Ready-pSIREN-RetroQ-ZsGreen) were constructed for interrupting the Zfx gene. Additionally, a recombined vector Psilencer/Zfy-shRNA was constructed for interrupting the Zfy gene. Male mice were randomly divided into 8 groups, with 20 animals per group. Five groups of mice were injected with PRZ1, PRZ2, PRZ3, PRZ4, and Psilencer/Zfy-shRNA vectors, respectively. The three control groups were injected with an equal volume of physiological saline, empty RNAi-Ready-pSIREN-RetroQ-ZsGreen vector, and empty Psilencer/Zfy-shRNA vector, respectively. All groups were injected every 7 days for a total of four injections. Fourteen days after the fourth injection, 10 male mice from each group were mated individually with 10 females. Testicular tissue of 10 male mice in each group was collected, and the expression level of Zfx/Zfy mRNA was determined by qRT-PCR. Results showed that, compared with the empty RNAi-Ready-pSIREN-RetroQ-ZsGreen vector and the physiological saline group, expression of Zfx mRNA decreased significantly after injection of PRZ1 (p 0.01), PRZ3 (p 0.01), and PRZ4 (p 0.01), and 78.75 ± 7.50% of the offspring were male in PRZ4 group, significantly higher than the offspring derived from the empty RNAi-Ready-pSIREN-RetroQ-ZsGreen vector and physiological saline group (p 0.01). In the PRZ1 group, the expression of Zfx mRNA was also significantly lower (p 0.01), but the male rate of offspring was not different (p 0.05). Conversely, the expression of Zfy mRNA decreased significantly after injection of Psilencer/Zfy-shRNA (p 0.01) and 31.00 ± 11.00% of the offspring were male, significantly lower than in the physiological saline group (p 0.01). In conclusion, our findings show that RNAi-mediated disruption of Zfx/Zfy in mouse testis affected X/Y spermatogenesis. Additionally, results suggest that the paralogous genes Zfx/Zfy play an important role in the process of X and Y sperm development. The individual interference of Zfx/Zfy may predict the outcome of X and Y haploid sperms. Presented herein is an advanced method developed to control mouse X/Y spermatogenesis and sex ratio of offspring.

Cystic echinococcosis (CE), caused by infection with the larval stage of the cestode Echinococcus granulosus , is a chronic zoonosis, to which sheep are highly susceptible. Previously, we found that Kazakh sheep with different MHC haplotypes differed in CE infection. Sheep with haplotype MHCMva Ibc-Sac IIab-Hin 1Iab were resistant to CE infection, while their counterparts without this haplotype were not. MicroRNAs (miRNAs), a class of small non-coding RNAs, are key regulators of gene expression at the post-transcriptional level and play essential roles in fundamental biological processes such as development and metabolism. To identify microRNA controlling resistance to CE in the early stage of infection, microRNA profiling was conducted in the intestinal tissue of sheep with resistant and non-resistant MHC haplotypes after peroral infection with E. granulosus eggs. A total of 351 known and 186 novel miRNAs were detected in the resistant group, against 353 known and 129 novel miRNAs in the non-resistant group. Among these miRNAs, 83 known miRNAs were significantly differentially expressed, including 75 up-regulated and 8 down-regulated miRNAs. Among these known microRNAs, miR-21-3p, miR-542-5p, miR-671, miR-134-5p, miR-26b, and miR-27a showed a significantly higher expression in CE-resistant sheep compared to the CE-non-resistant library, with the FC > 3. Functional analysis showed that they were NF-kB pathway-responsive miRNAs, which are involved in the inflammation process. The results suggest that these microRNAs may play important roles in the response of intestinal tissue to E. granulosus .

The electro-osmotic drag coefficients (ξ) of water-vapor equilibrated Nafion® 117, a proton conductor, and Tokuyama® A201, a hydroxide conductor were determined from the steady-state voltage of a water concentration cell. The ξ values are reported, along with water uptake, ion-exchange capacity, ionic conductivity, and methanol permeability of these membranes. The room-temperature ξ of Nafion® 117 and Tokuyama® A201 is 0.99 (±0.07) and 0.61 (±0.12), respectively, and is relatively independent of water content over the relative humidity range of 14–96%. The time to steady potential in the water concentration cell was longer for the Tokuyama® A201 membrane than the Nafion® 117 membrane, which is tentatively attributed to the lower mobility of hydrated hydroxide (or carbonate from absorption of adventitious carbon dioxide) in comparison to hydronium ion.

A proton exchange membrane (PEM) fuel cell with a flow field that can be switched between the serpentine and the interdigitated flow modes was used to measure the liquid water saturation level in the gas diffusion layer (GDL) of the cathode and the effect of the liquid water saturation level on the fuel cell performance. Using correlations between the liquid water saturation level and gas relative permeability obtained by neutron imaging, the liquid water saturation level in the GDL under serpentine flow mode was determined by the gas pressure drop across the GDL right after the flow field was switched from the serpentine mode to interdigitated mode. The results showed that the saturation levels in the cathode GDL during the interdigitated mode was much lower than that during the serpentine mode leading to better oxygen gas access to the cathode catalyst layer and consequently better fuel cell performance, especially at high current densities and low oxygen stoichiometric flow rate. In most cases, the fuel cell became unstable when the average liquid water saturation level exceeded 20%.

A Proton Exchange Membrane (PEM) fuel cell with a flow field that can be switched between the serpentine flow mode and the interdigitated flow mode was used to measure the liquid water saturation level in the gas diffusion layer (GDL) of the cathode. The gas pressure drop across the GDL was used along with the correlations between the saturation level and gas relative permeability obtained by neutron imaging to determine the liquid water saturation level in the GDL during operation. The results showed that the saturation levels in the cathode GDL during the interdigitated mode was much lower than that during the serpentine mode leading to better oxygen gas access to the cathode catalyst layer and consequently better fuel cell performance, especially at high current densities and low oxygen stoichiometric flow rate.

A new video watermarking method for the Audio Video coding Standard (AVS) is proposed. According to human visual masking properties, this method determines the region of interest for watermark embedding by analyzing video semantics, and generates dynamic robust watermark according to video motion semantics, and embeds watermarks in the Intermediate Frequency (IF) Discrete Cosine Transform (DCT) coefficients of the luminance sub-block prediction residual in the region of interest. This method controls watermark embedding strength adaptively by video textures semantics. Experiments show that this method is robust not only to various conventional attacks, but also to re-frame, frame cropping, frame deletion and other video-specific attacks.

In this study, experimental results of the micro-pump and volume displacement methods were compared to elucidate the root-cause of hysteresis in capillary pressure measurements. It was shown that hysteresis between the imbibition curve and drainage curve was apparent in the capillary curve of the micro-pump system. The measured capillary pressure curves by the micro-pump technique were observed to be highly dependent on the pump rate. Results of the volume displacement method showed that the hydrophobic layer affected both imbibition and drainage processes. Results showed higher pressure was needed to introduce water into the sample and hysteresis was observed only when the hydrophobic layer was used.

In this study, a two-phase flow model focusing on anode side was developed to investigate the effect of the properties of the porous media in anode side on the performance of a proton exchange membrane (PEM) fuel cell. Two cases (with and without micro-porous layer (MPL) in anode side) were included to elucidate the proper water management strategy in the anode side. The results showed that an MPL in the anode side might lead to flooded anode catalyst layer (CL) as well as flooded cathode. The increased saturation levels in the PEM fuel cell may cover the active catalyst sites, occupy the reactant transport path, and eventually lead to bad fuel cell performance. For the case without an MPL in the anode side, the amount of liquid water pushed from the cathode side to the anode side was sufficient to saturate the dry fuel in the anode side.

In this study, a model was developed to evaluate the role of the micro-porous layer (MPL) and the effects of its properties on the liquid water saturation levels in the cathode porous media and the performance of a proton exchange membrane (PEM) fuel cell. The results validated that the fuel cell performance was improved by adding an MPL between the macro-porous gas diffusion layer (GDL) and the catalyst layer (CL) in the cathode side. The MPL, due to its high hydrophobicity, increases the liquid water pressure in the cathode to the levels much higher than those in the anode resulting in an increased back-transport rate of liquid water from the cathode to the anode. The more hydrophobic the MPL is, the higher liquid pressure increases, and, consequently, the higher driving force is created across the membrane to drive water from the cathode to the anode.

Two-phase transport exists in the cathode of a PEMFC because liquid water is generated during operation by the oxygen reduction reaction and electro-osmotic drag of water from the anode. Its presence affects the transport rate of oxygen to the reactive sites in the catalyst layer of the cathode by reducing the gas pore volume and blocking the catalyst surface. To study the impact of the two-phase transport properties of the GDL and CL on the liquid water transport rate and the effect of the liquid water saturation levels in these porous layers on the performance of a PEMFC, a two-phase model using experimentally measured two-phase transport properties is developed. The simulated results show that the fuel cell performance and the liquid water saturation levels in the CL and GDL depend on both the individual two-phase properties of these two components and their interactions at the GDL/CL interface.

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This study investigated gas and liquid relative permeability, one of the important two-phase transport properties of the porous media used in proton exchange membrane (PEM) fuel cells. The experiment showed that the gas relative permeability obtained by the gravimetric analysis and neutron imaging agreed at low saturation levels, but differs at high saturation levels. The liquid relative permeability in the saturation level range of 0.3 to 0.8 was measured by neutron imaging. Because of dead air pockets in the porous materials and certain saturation levels are required to establish continuous flow of liquid water through gas diffusion media, liquid permeability at both high and low saturation levels could not be obtained. It was shown that the 3rd-order power correlation of gas permeability generally used in numerical simulation only fitted the porous media of A1 and A3 at low saturation levels.

In this study, a model was developed to evaluate the effects of the microporous layer (MPL) on the net liquid water transport rate across the membrane. The results support the hypothesis that the improvement in fuel cell performance observed when an MPL is used in the cathode side is related to its effect on the water transport process in the electrode and membrane. Due to its high hydrophobicity, the MPL increases the liquid water pressure in the cathode to levels much higher than that in the anode, resulting in an increased back-transport rate of liquid water from the cathode to the anode. This reduces the amount of water that is transported out of the cathode through the gas diffusion layer (GDL) to the cathode flow channels resulting in a lower saturation level in the GDL, and consequently, faster oxygen transport to the catalyst sites. This model showed that the state of zero-net-water-transport-across-the-membrane could be achieved with the appropriate capillary properties of the porous media. Two capillary properties of the MPL identified to have the greatest impact on the proton-exchange-membrane (PEM) fuel cell performance are the liquid water saturation level at p c = 0 (p g = p l ) and the slope of the capillary curve in the hydrophobic region.

This study investigated gas and liquid relative permeability, one of the important two-phase transport properties of the porous media used in proton exchange membrane fuel cells. The experiment showed that the gas relative permeability obtained by the gravimetric analysis and neutron imaging agreed at low saturation levels, but differs at high saturation levels. The liquid relative permeability in the saturation level range of 0.3 to 0.8 was measured by neutron imaging. Because of dead air pockets in the porous materials and certain saturation levels are required to establish continuous flow of liquid water through gas diffusion media, liquid permeability at both high and low saturation levels could not be obtained. It was shown that the 3rd-order power correlation of gas permeability generally used in numerical simulation only fitted the porous media of A1 and A3 at low saturation levels.

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A two-phase model was developed to study the impact of the capillary property of the gas diffusion (GDL) and catalyst layers (CL) and the saturation-level jump condition at the interface between these two dissimilar materials on the liquid water transport rate and the liquid water saturation levels in these porous layers and the performance of the cathode of a proton exchange membrane fuel cell (PEMFC). The study involves adjusting various aspects of the capillary curves of these porous layers and studying how these changes affect the cathode electrochemical performance to identify the most sensitive aspects. The simulated results show that fuel cell performance and the liquid water saturation levels in the CL and GDL depend on both the individual two-phase properties of these components and their interactions at the GDL/CL interface. The boundary condition at the GDL/ channel interface for saturated air operation constrains the transport phenomenon in the GDL and CL to the hydrophobic regions of the capillary pressure curves. It was also found that capillary properties of the GDL had a more significant effect on the fuel cell performance than those of the CL, and better fuel cell performance was obtained with GDL and CL with high capillary diffusion capability and low hydrophilic porosity.