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The accumulation of a disease-specific isoform of prion protein (PrPSc) and histopathological lesions, such as neuronal loss, are unevenly distributed in the brains of humans and animals affected with prion diseases. This distribution varies depending on the diseases and/or the combinations of prion strain and experimental animal. The brain region-dependent distribution of PrPSc and neuropathological lesions suggests a neuronal cell-type-dependent prion propagation and vulnerability to prion infection. However, the underlying mechanism is largely unknown. In this study, we provided evidence that the prion 22L strain propagates more efficiently in excitatory neurons than inhibitory neurons and that excitatory neurons in the thalamus are vulnerable to prion infection. PrPSc accumulation was less intense in the striatum, where GABAergic inhibitory neurons predominate, compared to the cerebral cortex and thalamus, where glutamatergic excitatory neurons are predominant, in mice intracerebrally or intraperitoneally inoculated with the 22L strain. PrPSc stains were observed along the needle track after stereotaxic injection into the striatum, whereas they were also observed away from the needle track in the thalamus. Consistent with inefficient prion propagation in the striatum, the 22L prion propagated more efficiently in glutamatergic neurons than GABAergic neurons in primary neuronal cultures. RNAscope in situ hybridization revealed a decrease in Vglut1- and Vglut2-expressing neurons in the ventral posterolateral nuclei of the thalamus in 22L strain-infected mice, whereas no decrease in Vgat-expressing neurons was observed in the adjacent reticular nucleus, mainly composed of Vgat-expressing interneurons. The excitatory neuron-prone prion propagation and excitatory neuronal loss in 22L strain-infected mice shed light on the neuropathological mechanism of prion diseases.

Shiga toxin-producing Escherichia coli (STEC) are associated with severe infections including hemorrhagic colitis and hemolytic uremic syndrome in humans. Ruminants are known as reservoirs of STEC; however, no data are available on STEC in ruminants in Mongolia, where more than 5 million cattle and 25 million sheep are raised. To disclose the existence and characteristics of STEC in Mongolia, in this study, we isolated and characterized STEC from cattle in Mongolia. We collected 350 rectal swabs of cattle from 30 farms near Ulaanbaatar city and isolated 45 STEC from 21 farms. Rectal swabs were precultured with modified Escherichia coli broth and then inoculated to Cefixime-Tellurite Sorbitol MacConkey agar plate and/or CHROMagar STEC agar plate for the isolation of STEC. The isolation ratios in each farm were from 0% to 40%. Multiplex PCR for the estimation of O- and H-serotypes identified 12 O-genotypes (Og-types) and 11 H-genotypes (Hg-types) from 45 isolates; however, Og-types of 19 isolates could not be determined. Stx gene subtyping by PCR identified 2 stx1 subtypes (1a and 1c) and 4 stx2 subtypes (2a, 2c, 2d, and 2g). Forty-five isolates were divided into 21 different groups based on the Og- and Hg-types, stx gene subtypes and the existence of virulence factors, ehxA, eae, and saa, which includes several major serotypes associated with human illness such as O26:H11 and O157:H7. The most dominant isolate, OgUT:H19 [stx1a (+), stx2a (+), ehxA (+) and saa (+)], was isolated from eight farms. This is the first report on the characterization of STEC in cattle in Mongolia, and the results suggest the importance of further monitoring of STEC contamination in the food chains as well as STEC infection in humans.

Abstract Objective SLITs are secreted glycoproteins that bind to Roundabouts (ROBOs) which are a family member of transmembrane receptors. SLIT signaling has well-conserved roles in mediating axon repulsion in a developing nervous system. We previously reported that SLIT1 mRNA is enriched in middle layers of the prefrontal cortex of macaque monkeys in a developmentally regulated manner. Other SLIT (SLIT2 and SLIT3) mRNAs showed preferential expressions in the prefrontal cortex with a distinct laminar pattern. To obtain further clues to the role of SLIT signaling in the organization of the primate brain, we performed ISH analysis of SLIT and ROBO mRNAs using adult macaque brain tissues. Results In this study, we examined the expression patterns of SLITs and ROBOs (ROBO1 and ROBO2) in other brain regions, and found intense and characteristic expression patterns of these genes in the entorhinal-hippocampal area. In situ hybridization analysis revealed that SLIT1 and SLIT2 mRNAs showed marked complementary distribution in the entorhinal cortex. SLIT and ROBO mRNAs were widely expressed in the hippocampus with modest regional preference. These findings suggest that each SLIT gene has a specialized role that is particularly important for prefrontal as well as hippocampal connectivity in the primate cortex.

The Hadron Experimental Facility at the Japan Proton Accelerator Research Complex is used for various nuclear and elementary particle physics experiments that use secondary particle beams. The secondary-particle production target is a key element for the generation of particles such as kaons and pions. To increase beam power, a new target was developed and installed. The target, which is made of gold and indirectly cooled with water, was designed so that the maximum stresses do not exceed the allowable stresses determined based on the pressure vessel standard. 95 kW is considered to be the maximum power of the primary proton beam for a 5.2-s beam duration. The new target was stably operated up to a power of 65 kW. In addition, beam position estimation based on multipoint temperature measurements of the target was demonstrated.

Previous researches provided a reactive scheduling method using a genetic algorithm to improve disturbed production schedules, due to unexpected disruptions, such as delays of manufacturing operations. This paper deals with an extension of the reactive scheduling method to modify not only the loading sequences but also machining sequences of jobs by using a co-evolutionary genetic algorithm. Two different kinds of individuals for the loading sequences and the machining sequences are generated and improved in co-evolutionary processes. A prototype of new reactive scheduling system was developed, and the effectiveness of the proposed method was verified through computational experiments.

The mammalian retina has more diversity of neurons than scientists had once believed in order to establish complicated vision processing. In the monkey retina, morphological diversity of retinal ganglion cells (RGCs) besides dominant midget and parasol cells has been suggested. However, characteristic subtypes of RGCs in other species such as bistratified direction-selective ganglion cells (DSGC) have not yet been identified. Increasing interest has been shown in the common marmoset (Callithrix jacchus) monkey as a "super-model" of neuroscientific research. Here, we established organotypic tissue culture of the adult marmoset monkey retina with particle-mediated gene transfer of GFP to survey the morphological diversity of RGCs. We successfully incubated adult marmoset monkey retinas for 2 to 4 days ex vivo for transient expression of GFP. We morphologically examined 121 RGCs out of more than 3240 GFP-transfected cells in 5 retinas. Among them, we identified monostratified or broadly stratified ganglion cells (midget, parasol, sparse, recursive, thorny, and broad thorny ganglion cells), and bistratified ganglion cells (recursive, large, and small bistratified ganglion cells [blue-ON/yellow-OFF-like]). By this survey, we also found a candidate for bistratified DSGC whose dendrites were well cofasciculated with ChAT-positive starburst dendrites, costratified with ON and OFF ChAT bands, and had honeycomb-shaped dendritic arbors morphologically similar to those in rabbits. Our genetic engineering method provides a new approach to future investigation for morphological and functional diversity of RGCs in the monkey retina.

Japan Aerospace Exploration Agency (JAXA) has planned High-Mach Integrated Control Experiment (HIMICO), which is a flight experiment under hypersonic conditions. The ramjet engine used in the experimental aircraft is designed for self-ignition of the fuel to occur due to high temperature caused by aerodynamic heating in hypersonic flow. We confirmed that self-ignition occurred under some test conditions in the combustion test. However, conditions of the incoming air and the injected fuel where self-ignition occurred were not clear. In this study, we develop a chemically reacting flow solver for investigating the self-ignition. Large-eddy simulations of the combustor of the HIMICO engine are performed using a detailed hydrogen-air reaction mechanism. The results show that qualitative prediction whether self-ignition occurs is possible by Large-eddy simulations using the solver. In the simulations, self-ignition occurs even under conditions where self-ignition did not occur in the test. On the other hand, it is found that the selection of the boundary condition of the injector outer walls has a great effect on the time to self-ignition. For improving the accuracy of prediction, it is necessary to consider turbulence and three-dimensional flow due to the intake and the effects of heat exchange on the injector outer walls. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a fibrous assembly of carbon nanotubes (CNTs) induced by a gas discharge breakdown that bridge the distance between two planar electrodes. To achieve this, we placed the two planar electrodes, one of which was covered with a CNT film, in a chamber; a vacuum pump was used to evacuate the air from the chamber and replace it with inert gas. By then applying a voltage between the electrodes, we induced a discharge breakdown between them. This caused the CNTs coated on the electrode surface to detach and form fibrous assemblies. The assemblies elongated and reached the opposite electrode, thereby creating bridges between the electrodes. These bridges formed when the gas pressure was greater than ca. 1.0×103Pa and in combination with the occurrence of a spark discharge. At lower pressures, a glow discharge occurred, and no bridge formation was observed, indicating that the discharge mode is critical for the bridge formation. [ABSTRACT FROM AUTHOR]

Systemic and cellular zinc homeostasis is elaborately controlled by ZIP and ZnT zinc transporters. Therefore, detailed characterization of their expression properties is of importance. Of these transporter proteins, Zip4 functions as the primarily important transporter to control systemic zinc homeostasis because of its indispensable function of zinc absorption in the small intestine. In this study, we closely investigated Zip4 protein accumulation in the rat small intestine in response to zinc status using an anti-Zip4 monoclonal antibody that we generated and contrasted this with the zinc-responsive activity of the membrane-bound alkaline phosphatase (ALP). We found that Zip4 accumulation is more rapid in response to zinc deficiency than previously thought. Accumulation increased in the jejunum as early as 1 day following a zinc-deficient diet. In the small intestine, Zip4 protein expression was higher in the jejunum than in the duodenum and was accompanied by reduction of ALP activity, suggesting that the jejunum can become zinc deficient more easily. Furthermore, by monitoring Zip4 accumulation levels and ALP activity in the duodenum and jejunum, we reasserted that zinc deficiency during lactation may transiently alter plasma glucose levels in the offspring in a sex-specific manner, without affecting homeostatic control of zinc metabolism. This confirms that zinc nutrition during lactation is extremely important for the health of the offspring. These results reveal that rapid Zip4 accumulation provides a significant conceptual advance in understanding the molecular basis of systemic zinc homeostatic control, and that properties of Zip4 protein accumulation are useful to evaluate zinc status closely. [ABSTRACT FROM AUTHOR]

To improve the computational performance of the laminar flamelet model for compressible flow (the compressible flamelet model), two formulations of the heat flux term are proposed: form1 achieves efficient calculation of the spatial gradient of the mass fraction of each chemical species, and form2 eliminates the dependence of the calculation process on the number of chemical species. Based on these formulations, three methods are proposed that use linear interpolation (lerp) or an artificial neural network (ANN) for their flamelet tables: form1-ann, form2-lerp, and form2-ann. First, it will be shown that the accuracy of the ANN in the proposed form1-ann and form2-ann methods is sufficient for numerical simulations. Then, to evaluate the form2-lerp and form2-ann methods and show that they can greatly improve the computational performance of the conventional method, numerical simulations will be conducted for the scramjet test-engine combustor of the German Aerospace Center, DLR. The calculation time of the form2-lerp method is reduced by about 0.878 times, and the memory usage is increased by about 2.97 times compared with the values for the conventional method. The calculation time of the form2-ann method is reduced by about 0.946 times, and the memory usage is reduced by about 0.508 times compared with the conventional method. [ABSTRACT FROM AUTHOR]