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This study aims to improve the performance of the vertical axis wind turbine using a J-type airfoil shape. In this study we used an optimal airfoil shape called Opt-VF that was obtained in previous research using an optimization method of the Kriging surrogate model approach. We aimed to improve the performance of the optimal airfoil utilizing the J-type airfoil shape, by the realization of good balance to utilize lift and drag forces. 2D computational fluid dynamics (CFD) simulations and experimental performance measurements were performed to confirm the efficiency of the J-type airfoil designs. We designed/evaluated various types of the Jtype airfoils to find the most efficient condition for the optimal airfoil. We also performed flow visualizations to observe the difference between the original and J-type airfoils in detail. Some J-type airfoils achieved better performance than the original optimal airfoil, by generating higher pressure in the inner side of the J-type airfoil and obtaining higher velocity wind flow around the leading edge at certain rotational angles. Finally, experimental evaluations were conducted to compare with the CFD results. Same trends could be confirmed between the CFD and experimental results. In the experimental evaluations, maximum values of power coefficient were increased about 7% and 4% at the cases of two-blades and three-blades, respectively, compared to the original Opt-VF airfoil. These results demonstrated the effectiveness introducing the J-type airfoil shape in the optimal airfoil.

Background: Controlling novel coronavirus pandemic infection (COVID-19) is a global challenge, and highly sensitive testing is essential for effective control. The saliva is a promising sample for high-sensitivity testing because it is easier to collect than nasopharyngeal swab samples and allows large-volume testing. Results: We developed a simple SARS-CoV-2 concentration method from saliva samples that can be completed in less than 60 min. We performed a spike test using 12 ml of saliva samples obtained from healthy volunteer people, and the developed method performance was evaluated by comparison using a combination of automatic nucleic acid extraction followed by RT-qPCR detection. In saliva spike tests using a 10-fold dilution series of SARS-CoV-2, the developed method was consistently 100-fold more sensitive than the conventional method. Conclusions: The developed method can improve the analytical sensitivity of the SARS-CoV-2 test using saliva and speed up and save labor in screening tests by pooling many samples. Furthermore, the developed method has the potential to contribute to the highly sensitive detection of various human and animal viral pathogens from the saliva and various clinical samples.

Abstract Intracellular ice formation during cryopreservation is lethal to the cell, including during warming. Here, we examined the effect of sample volume and warming rate on the cryopreservation success of 1-cell rat embryos based on successful development into blastocysts in vitro and to term in vivo following embryo transfer. Embryos were equilibrated in 5% propylene glycol solution for 10 min, held for 40 s at 0 °C in cryopreservation solution (5%PG + PEPeS), and cooled by immersion in liquid nitrogen. When 1-cell embryos were cryopreserved in a volume of 30–100 μL at a cooling rate of 5830–7160 °C/min and warmed at 35,480–49,400 °C/min by adding 1 mL of 0.3 M sucrose solution at 50 °C, 17.3–28.8% developed into blastocysts, compared with 57.0% of untreated embryos. However, when 1-cell embryos were cryopreserved in a smaller volume of 15 μl at 7950 °C/min and warmed at 68,850 °C/min, 58.8 ± 10.6% developed into blastocysts and 50.0 ± 7.4% developed to term, comparable to that of non-treated embryos (57.0 ± 5.4% and 51.4 ± 3.1%, respectively). Cryopreserved embryos at other developmental stages also showed high in vitro culture potential similar to that of the control. Using a conventional cryotube and a small-volume vitrification procedure with rapid warming, we achieved high levels of subsequent rat embryonic development at all developmental stages.

Abstract Background While early detection and early containment are key to controlling the African swine fever (ASF) pandemic, the lack of practical testing methods for use in the field are a major barrier to achieving this feat. Objectives To describe the development of a rapid and sensitive point‐of‐care test (POCT) for ASF, and its evaluation using swine whole blood samples for field settings. Methods In total, 89 swine whole blood samples were collected from Vietnamese swine farms and were performed the POCT using a combination of crude DNA extraction and LAMP (loop‐mediated isothermal amplification) amplification. Results The POCT enabled crude DNA to be extracted from swine whole blood samples within 10 min at extremely low cost and with relative ease. The entire POCT required a maximum of 50 min from the beginning of DNA extraction to final judgment. Compared to a conventional real‐time PCR detection, the POCT showed a 1 log reduction in detection sensitivity, but comparable diagnostic sensitivity of 100% (56/56) and diagnostic specificity of 100% (33/33). The POCT was quicker and easier to perform and did not require special equipment. Conclusions This POCT is expected to facilitate early diagnosis and containment of ASF invasion into both regions in which it is endemic and eradicated.

Efficient aerodynamic shape optimizations are realized in this research utilizing dimension reduction technologies. Several dimension reduction methods such as proper orthogonal decomposition, independent component analysis, kernel principal component regression and deep auto encoder, are investigated to reduce the dimensionality of design variables space. The number of design variables can be efficiently reduced by the proposed approach while obtained optimization results are comparable with that of a conventional optimization approach. The effect of each dominant mode is clarified in this study. A variable fidelity method is introduced by adopting a low-fidelity performance evaluation in the pre-process of the dimension reduction. By introducing the variable fidelity method, a multi objective aerodynamic shape optimization problem can be efficiently solved. Furthermore, design knowledge with respect to the tradeoff relationship between objective functions can be obtained from the results of dimension reduction.

Busemann’s supersonic biplane airfoil can reduce wave drag through shock interactions at its designed freestream Mach number. However, a choking phenomenon occurs with a decrease in the freestream Mach number, and the drag coefficient increases significantly, resulting in an aerodynamic problem with a discontinuous change in the performance function. In this study, an uncertainty analysis method, the divided inexpensive Monte Carlo simulation (IMCS), is proposed to solve discontinuous problems efficiently and is applied to Busemann’s biplane airfoil. In the divided IMCS, the discontinuity point is determined using a simple sampling method. The uncertainty input space is divided at the detected discontinuity point, and a surrogate model is constructed for each space. Uncertainty analysis was performed using the constructed surrogate models, and the results of the divided IMCS showed qualitative agreement with those of the conventional Monte Carlo simulation, which is the most straightforward uncertainty analysis method. Moreover, the divided IMCS significantly reduced the computational cost of the uncertainty analysis. A robust design optimization of the supersonic biplane airfoil was performed using the divided IMCS, yielding more robust designs than Busemann’s biplane airfoil. The usefulness of the divided IMCS for uncertainty analysis of discontinuous problems was confirmed.

Background: Direct detection tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that bypass complicated nucleic acid/antigen purification steps are promising tools for the rapid diagnosis of coronavirus disease 2019 (COVID-19). Methods: To determine the analytical and clinical diagnostic performances of the direct detection assays, we compared 6 direct molecular detection assays, including two loop-mediated isothermal amplification (LAMP) assays and one lateral flow antigen assay, against the reference extraction-based RT-PCR assay using 183 respiratory samples (87 nasopharyngeal swabs, 51 saliva samples, and 45 sputum samples). Results: Analytical sensitivity analysis showed that the direct RT-PCR assay of Toyobo exhibited the lowest LOD of 1,000 copies/mL. Compared with the 80 positive and 103 negative samples based on the reference assay, the Toyobo assay had the highest positive percent agreement (PPA) of 96.3%, followed by the two direct RT-PCR assays of Takara and Shimadzu and one LAMP assay of Eiken (86.3–87.5%). The Fujirebio antigen assay had the lowest PPA of 44.7% among the assays tested. The negative percent agreement of these direct detection assays was 100%, except for the Eiken assay (96.3%). Conclusions: Large differences in PPA existed among the direct detection tests. Laboratories need to take these characteristics into consideration before implementing these assays.

The pandemic caused by novel coronavirus disease of 2019 (COVID-19) is a global threat. Wastewater surveillance in Japan and abroad has led to the detection of SARS-CoV-2, causing concern that SARS-CoV-2 in the feces of infected persons may contaminate the aquatic environment. Bivalves such as oysters cultivated in coastal areas are known to filter and concentrate viruses such as norovirus present in seawater in their bodies; however, whether they do so with SARS-CoV-2 is unknown. Therefore, we examined cultivated oysters sold in Japan for the presence of SARS-CoV-2 between October 2021 and April 2022 to clarify the extent of viral contamination and evaluate the risk of food-borne transmission of SARS-CoV-2. Porcine epidemic diarrhea virus (PEDV), known as pig coronavirus, was used to spike midgut-gland samples as a whole process control. The presence of SARS-CoV-2 and PEDV was investigated using a modified polyethylene glycol precipitation method and RT-qPCR. While all samples spiked with the whole process control were positive, no SARS-CoV-2 was detected in any of the 145 raw oyster samples surveyed, despite a marked increase in infections caused by the Omicron variant from January to April 2022 in Japan. Therefore, our results suggest that with well-developed sewage treatment facilities, consumption of oysters cultivated in coastal areas may not be a risk factor for SARS-CoV-2 outbreaks.

The sex chromosome complement, XX or XY, determines sexual differentiation of the gonadal primordium into a testis or an ovary, which in turn directs differentiation of the germ cells into sperm and oocytes, respectively, in eutherian mammals. When the X monosomy or XY sex reversal occurs, XO and XY females exhibit subfertility and infertility in the mouse on the C57BL/6J genetic background, suggesting that functional germ cell differentiation requires the proper sex chromosome complement. Using these mouse models, we asked how the sex chromosome complement affects gene transcription in the oocytes during follicular growth. An oocyte accumulates cytoplasmic components such as mRNAs and proteins during follicular growth to support subsequent meiotic progression, fertilization, and early embryonic development without de novo transcription. However, how gene transcription is regulated during oocyte growth is not well understood. Our results revealed that XY oocytes became abnormal in chromatin configuration, mitochondria distribution, and de novo transcription compared to XX or XO oocytes near the end of growth phase. Therefore, we compared transcriptomes by RNA-sequencing among the XX, XO, and XY oocytes of 50–60 µm in diameter, which were still morphologically comparable. The results showed that the X chromosome dosage limited the X-linked and autosomal gene transcript levels in XO oocytes whereas many genes were transcribed from the Y chromosome and made the transcriptome in XY oocytes closer to that in XX oocytes. We then compared the transcript levels of 3 X-linked, 3 Y-linked and 2 autosomal genes in the XX, XO, and XY oocytes during the entire growth phase as well as at the end of growth phase using quantitative RT-PCR. The results indicated that the transcript levels of most genes increased with oocyte growth while largely maintaining the X chromosome dosage dependence. Near the end of growth phase, however, transcript levels of some X-linked genes did not increase in XY oocytes as much as XX or XO oocytes, rendering their levels much lower than those in XX oocytes. Thus, XY oocytes established a distinct transcriptome at the end of growth phase, which may be associated with abnormal chromatin configuration and mitochondria distribution.

Se desarrolló un método de amplificación isotérmica mediada en lazo de transcriptasa inversa (RT-LAMP) para detectar Zika. Los primers se diseñaron basándose en la región NS5 de 64 genomas completos. Se usó reactivo LAMP liofilizado. Inicialmente, se probaron siete arbovirus diferentes y solo las muestras de Zika resultaron positivas. Además, las diluciones seriadas de una de los ARN de Zika se compararon mediante RT-LAMP y qRT-PCR, demostrando que RTLAMP es 1000 veces más sensible. También se evaluó 300 muestras de suero usando RT-LAMP y los resultados se compararon con los métodos de qRT-PCR estándar y obtuvimos un 99,3% (IC95%: 97,7 - 100,0) de sensibilidad, 100% (IC95%: 99,7 - 100,0) de especificidad, 100% (IC95%: 99,7 -100,0) de valor predictivo positivo y 99,3% (IC95%: 97,7 - 100,0) de valor predictivo negativo. En conclusión, este método brinda una alternativa de bajo costo, alto rendimiento, viabilidad y confiabilidad para el diagnóstico rápido de Zika en instalaciones de atención primaria de salud.

Coral communities around the world are projected to be negatively affected by ocean acidification. Not all coral species will respond in the same manner to rising CO2 levels. Evidence from naturally acidified areas such as CO2 seeps have shown that although a few species are resistant to elevated CO2, most lack sufficient resistance resulting in their decline. This has led to the simple grouping of coral species into “winners” and “losers,” but the physiological traits supporting this ecological assessment are yet to be fully understood. Here using CO2 seeps, in two biogeographically distinct regions, we investigated whether physiological traits related to energy production [mitochondrial electron transport systems (ETSAs) activities] and biomass (protein contents) differed between winning and losing species in order to identify possible physiological traits of resistance to ocean acidification and whether they can be acquired during short-term transplantations. We show that winning species had a lower biomass (protein contents per coral surface area) resulting in a higher potential for energy production (biomass specific ETSA: ETSA per protein contents) compared to losing species. We hypothesize that winning species inherently allocate more energy toward inorganic growth (calcification) compared to somatic (tissue) growth. In contrast, we found that losing species that show a higher biomass under reference pCO2 experienced a loss in biomass and variable response in area-specific ETSA that did not translate in an increase in biomass-specific ETSA following either short-term (4–5 months) or even life-long acclimation to elevated pCO2 conditions. Our results suggest that resistance to ocean acidification in corals may not be acquired within a single generation or through the selection of physiologically resistant individuals. This reinforces current evidence suggesting that ocean acidification will reshape coral communities around the world, selecting species that have an inherent resistance to elevated pCO2.

This study aimed to seek for the optimal condition for small-scale larviculture of red seabream Pagrus major larvae. We examined the effects of tank shapes and aerations, which were assumed to influence the larval survival, growth and swim bladder inflation of P. major larvae. Seawater (50-l) was filled into three cylindrical (CT: 1.7 × 103 cm2 water surface area, 30 cm deep) and six rectangular (RT: 1.8 × 103 cm2 water surface area, 28 cm deep) tanks. One air stone with 100 ml/min aeration rate was set at the bottom center of three CT and RT (RT1AS), and two air stones with 50 ml/min aeration rate were set at the half bottom center of three RT (RT2AS). Five hundred eggs were distributed into each experimental tank. Rotifers were fed to larvae at 10 individuals/mL on 3 days post hatching (dph) and their distribution in tanks were measured. Survival rate at 14 dph in CT (54.7 ± 11.0 %) and RT1AS (55.3 ± 6.0 %) were significantly higher than that in RT2AS (29.6 ± 9.3 %, p < 0.05). However, the growth of larvae was not significantly different between tank shapes and aerators. Swimbladder inflation rates were not different between tank shapes and aerations, however, CT (58.9±28.3 %) showed lower trend (RT1AS 94.4±6.9 %, RT2AS 92.2±10.7 %). Rotifer distribution in tanks was higher at tank bottom (p < 0.05). Low flow regions were observed along the side walls of the tanks and bottom areas in CT and RT1AS due to a single-pair vortex system and formed at the center (between air stones) and from the air stone to the tank walls in RT2AS due to two single-pair vortex systems. These low-flow areas were coincided with higher rotifer distribution areas at the tank bottom indicating that measuring rotifer density can estimate the flow in a tank. We recommend the rectangular tank with one air stone system for red seabream larvae.

Objectives: This study was intended to investigate the clinical and microbiological characteristics of patients with bacteremia caused by Campylobacter species. Methods: From April 1998 to May 2014, 56 adults with bacteremia caused by Campylobacter species were evaluated. These Campylobacter species isolates were confirmed to the species level using 16S rRNA gene sequencing (all isolates) and multiplex PCR analysis (for C. fetus only). The performance of identification for Campylobacter species by the Bruker Biotyper MALDI-TOF MS was evaluated. The genetic relatedness of C. fetus isolates was analyzed by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Results: The leading underlying medical conditions of these patients were malignancy (46.4%), hypertension (35.7%), and liver cirrhosis (23.2%). The overall 30-day mortality rate was 5.4%. Using 16S rRNA sequencing analysis, 26 isolates of C. coli, 11 of C. jejuni, and 19 of C. fetus, including 15 C. fetus subsp. fetus and five C. fetus subsp. venerealis, were identified. Among the five C. fetus subsp. venerealis isolates recognized by 16S rRNA gene sequencing, only two isolates were C. fetus subsp. venerealis by multiplex PCR method. The Bruker Biotyper MALDI-TOF MS failed to correctly identify C. fetus subsp. venerealis isolates. MLST analysis of C. fetus isolates revealed three STs: ST20 (n = 12), ST11 (n = 5), and ST57 (n = 2), which were compatible with three major PFGE clusters. Conclusion: Database expansion of MALDI-TOF MS for the correct identification of C. fetus to subspecies levels is needed. A novel clone of ST57-PFGE Cluster C of C. fetus subsp. venerealis was noted. Keywords: Campylobacter, Campylobacter fetus, API Campy system, Bruker Biotyper MALDI-TOF MS, 16S RNA gene sequencing, Multiplex PCR

A variable fidelity concept is introduced in a re-parameterization approach based on the proper orthogonal decomposition (POD) to efficiently solve multi-objective aerodynamic shape optimization problems. The re-parameterization approach enables to extract dominant shape deformation modes from a database of good designs and to reduce the number of design variables. The present variable fidelity approach is proposed by utilizing low-fidelity functional evaluations to select the good designs. The proposed approach is investigated in two multi-objective aerodynamic shape optimization problems of 2D airfoil in which the combinations of viscous/inviscid simulations or fine/coarse grid simulations are treated as the high/low-fidelity evaluation methods. It can be confirmed that dominant POD modes obtained from low-fidelity evaluations are qualitatively equivalent with that obtained from high-fidelity evaluations. Non-dominated solutions obtained from a conventional optimization approach can be reproduced with smaller numbers of design variables using the dominant POD modes. The computational costs to solve the multi-objective aerodynamic shape optimization problems can be dramatically reduced by introducing the variable fidelity concept.

Abstract Background Porcine epidemic diarrhoea (PED) is an emerging disease in pigs that causes massive economic losses in the swine industry, with high mortality in suckling piglets. Early identification of PED virus (PEDV)-infected herd through surveillance or monitoring strategies is necessary for mass control of PED. However, a common working diagnosis system involves identifying PEDV-infected animals individually, which is a costly and time-consuming approach. Given the above information, the thrusts of this study were to develop a real-time fluorescent reverse transcription loop-mediated isothermal amplification (RtF-RT-LAMP) assay and establish a pooled testing system using faecal sample to identify PEDV-infected herd. Results In this study, we developed an accurate, rapid, cost-effective, and simple RtF- RT-LAMP assay for detecting the PEDV genome targeting M gene. The pooled testing system using the RtF-RT-LAMP assay was optimized such that a pool of at least 15 individual faecal samples could be analysed. Conclusions The developed RtF-RT-LAMP assay in our study could support the design and implementation of large-scaled epidemiological surveys as well as active surveillance and monitoring programs for effective control of PED.

Human infections with Campylobacter fetus are often assumed to be derived from livestock. Here, Iraola et al. provide evidence that healthy humans may act as carriers and dispersers, and C. fetus may have originated in humans as an intestinal pathobiont and then adapted as a livestock pathogen.

We dealt with three-dimensional cellular premixed flames generated by hydrodynamic and diffusive-thermal instabilities to elucidate the effects of unburned-gas temperature and heat loss. To obtain the dispersion relation, a sinusoidal disturbance with sufficiently small amplitude was superimposed on a planar flame. As the unburned-gas temperature became lower and the heat loss became larger, the growth rate decreased and the unstable range narrowed, owing to the decrease of the burning velocity of a planar flame. Using the preheat zone thickness and burning velocity of a planar flame, the dispersion relation was normalized. With a decrease of unburned-gas temperature, the normalized growth rate increased and the normalized unstable range widened, which was because the temperature ratio of burned and unburned gases became larger. With an increase of heat loss, instability phenomena became noticeable, which was because diffusive-thermal instability became stronger. To investigate the characteristics of cellular flames generated by hydrodynamic and diffusive-thermal instabilities, we superimposed a disturbance with the critical wave number corresponding to the maximum growth rate. The superimposed disturbance evolved, and a hexagonal cellular flame formed. The obtained cellular fronts were qualitatively consistent with the experimental results. The cellular fronts became deeper as the unburned-gas temperature became lower, even though the growth rate decreased, which was due to the strength of thermal-expansion effects. As the heat loss became larger, the burning velocity of a cellular flame normalized by that of a planar flame increased. This was because diffusive-thermal effects became stronger owing to the increase of apparent Zeldovich number caused by the decrease of flame temperature.

A cross-sectional study was used to identify and assess prevalence and phenotypic antimicrobial resistance (AMR) profiles of Escherichia coli and other enterobacteria isolated from healthy wildlife and livestock cohabiting at a 10,000 acres game ranch near Lusaka, Zambia. Purposive sampling was used to select wildlife and livestock based on similarities in behavior, grazing habits and close interactions with humans. Isolates (n = 66) from fecal samples collected between April and August 2018 (n = 84) were examined following modified protocols for bacteria isolation, biochemical identification, molecular detection, phylogenetic analysis, and antimicrobial susceptibility testing by disc diffusion method. Data were analyzed using R software, Genetyx ver.12 and Mega 6. Using Applied Profile Index 20E kit for biochemical identification, polymerase chain reaction assay and sequencing, sixty-six isolates were identified to species level, of which Escherichia coli (72.7%, 48/66), E. fergusonii (1.5%, 1/66), Shigella sonnei (22.7%, 14/66), Sh. flexinerri (1.5%, 1/66) and Enterobacteriaceae bacterium (1.5%, 1/66), and their relationships were illustrated in a phylogenetic tree. Phenotypic antimicrobial resistance or intermediate sensitivity expression to at least one antimicrobial agent was detected in 89.6% of the E. coli, and 73.3% of the Shigella isolates. The E. coli isolates exhibited the highest resistance rates to ampicillin (27%), ceftazidime (14.3%), cefotaxime (9.5%), and kanamycin (9.5%). Multidrug resistance (MDR) was detected in 18.8% of E. coli isolates while only 13.3% Shigella isolates showed MDR. The MDR was detected among isolates from impala and ostrich (wild animals in which no antimicrobial treatment was used), and in isolates from cattle, pigs, and goats (domesticated animals). This study indicates the possible transmission of drug-resistant microorganisms between animals cohabiting at the wildlife–livestock interface. It emphasizes the need for further investigation of the role of wildlife in the development and transmission of AMR, which is an issue of global concern.

The distal part of the vastus medialis (VM) (VM obliquus: VMO) muscle acts as the medial stabilizer of the patella. However, it has been known to facilitate VMO contraction during training of the quadriceps femoris muscle in knee joint rehabilitation. This study aimed to examine the contribution degree of VMO as a knee joint extension torque generator. Sixteen healthy male volunteers participated in this study. Electrical muscle stimulation (EMS) was performed on VMO at 60° knee angle for 20 min to induce muscle fatigue. Knee extension twitch torques (TT) at 90° and 30° knee angle evoked by femoral nerve stimulation were measured before and after EMS. Although each TT at 90° and 30° knee angle significantly decreased after EMS, the decreased TT rate in both joint angles showed no significant difference. Our results show that VMO might contribute to the generation of the knee joint torque at the same level in the range from flexion to extension. Therefore, it was suggested that the facilitating the neural drive for VMO is important during the quadriceps femoris muscle strengthening exercise.

Canine monocytic ehrlichiosis caused by Ehrlichia canis is one of the leading tick-borne diseases of dogs, particularly in tropical countries. A highly sensitive and specific diagnostic method is essential for early detection to facilitate treatment. This study was conducted to develop E. canis loop-mediated isothermal amplification (LAMP) assay, a highly sensitive yet simple molecular technique, targeting the citrate synthase (gltA) gene of E. canis. Canine blood samples were subjected to conventional PCR targeting E. canis gltA. After analysis of the sequences of PCR amplicons, LAMP primers were generated. The optimum temperature and time for the LAMP assay were determined using eight samples—after which, the effectiveness and reproducibility of LAMP were verified by testing 40 samples, which included PCR-positive and negative samples. The detection limit was also established. The optimal condition for the assay was 61 °C for 60 min. Compared to PCR, the LAMP assay had a relative sensitivity and specificity of 92.5 and 100%, respectively. Statistical analysis using McNemar’s test showed that the E. canis LAMP assay has no significant difference with PCR. Therefore, the LAMP assay developed in this study may be used as an alternative to PCR in the detection of E. canis.

The objective of this research is to efficiently solve discontinuous optimization problems as well as optimization problems with large infeasible regions in the design variables space. Recently, major optimization targets have been changed to more complicated ones such as topology optimization problem, discontinuous optimization problem, robust optimization problem and high dimensional optimization problem. The aim of this research is to efficiently solve the complicated optimization problems by using machine learning technologies. In aerodynamic optimization problems at supersonic flow conditions, it is confirmed that aerodynamic objective functions have discontinuity due to shock waves and it needs to treat the discontinuous functions and large infeasible regions via strong shock waves. In this research, therefore, we develop an efficient global optimization method for discontinuous optimization problems with infeasible regions using classification method (EGODISC). The developed method is compared with a Bayesian optimization method using the Matern 5/2 kernel Gaussian process regression and a genetic algorithm to verify the usefulness of the developed method. The Bayesian optimization falls into an infinite loop in its optimization process by selecting an additional sample point in the infeasible regions. On the other hand, the developed method can work well with the infeasible regions in the design variables space. It is confirmed that EGODISC can be effectively used with discontinuous aerodynamic objective functions. It is also confirmed that EGODISC can be effectively used for a shape optimization problem with large infeasible regions by the negative thickness of airfoil.

In this research, 2D shallow water equations are expanded by an intrusive polynomial chaos approach for efficient uncertainty quantification in tsunami inundation flows. Uncertainty propagation can be evaluated by solving the expanded 2D shallow water equations, and then probability measures such as mean, standard deviation and probability density function can be obtained for arbitrary variables. An uncertain input is given on its initial condition of water height and/or bathymetry in dam break problems as well as in Thacker’s inundation flow problem. Obtained uncertainty quantification results are compared with (exact) Monte-Carlo simulation results to validate the developed approach. Qualitative agreement can be confirmed between the Monte-Carlo simulation and the developed approach. The computational cost of the developed approach is much more inexpensive than the Monte-Carlo simulation, so that inexpensive/accurate uncertainty quantification can be realized with the developed approach. By using the obtained results, stochastic hazard map considering uncertainties can be generated which will be beneficial to minimize potential damage via inundation flows.

An attempt of experiment / simulation integrated design optimization is performed for the blade airfoil shape of a vertical axis wind turbine. A variable fidelity Kriging surrogate model approach is utilized in this integrated design optimization, in which a surrogate model is constructed from both high-fidelity and low-fidelity sample points information. In this research, the high and low fidelity performance functions are respectively defined from experimental and numerical evaluation methods. In the numerical evaluation method, 2D steady computational fluid dynamics (CFD) simulations are performed for the evaluation of an airfoil shape. An optimal airfoil shape is explored on the accurate variable fidelity surrogate model which is constructed in 9 design variables space representing various blade airfoil shapes. The validity and effectiveness of the present integrated design optimization are discussed by comparing with another approximate optimal airfoil shape which is obtained only by CFD computations. The optimal design obtained by the developed approach showed 8% larger performance value in the experimental evaluation compared with the approximate optimal design. More efficient shape optimization can be realized by including the low-fidelity information, whose functional trends are utilized to construct accurate surrogate models.

The effects of unburned-gas temperature on the characteristics of cellular premixed flames generated by hydrodynamic and diffusive-thermal instabilities were numerically investigated. Two-dimensional reactive flow was calculated in large space, based on the compressible Navier-Stokes equations including a one-step irreversible chemical reaction. The dynamic behavior of cellular premixed flames, i.e. the coalescence and division of cells, appeared in large space owing to intrinsic instability. The behavior of flame fronts became more unstable with a decrease in unburned-gas temperature, even though the burning velocity of a planar flame reduced. This was due to the strength of thermal-expansion effects and to the enlargement of Zeldovich numbers. We found that the average burning velocity of a cellular flame normalized by that of a planar flame increased as the unburned-gas temperature became lower and the space size became larger. To elucidate the increase of burning velocity, we proposed the new model and showed that the normalized increment factor of burning velocity became larger under low unburned-gas temperature. In addition, we performed fractal analysis to consider the fractal dimension for three-dimensional flow. The obtained fractal dimension corresponding to laminar flames was nearly identical to the experimental and numerical results of turbulent flames.

Bovine digital dermatitis (DD) is a severe infectious cause of lameness in cattle worldwide, with important economic and welfare consequences. There are three treponeme phylogroups (T. pedis, T. phagedenis, and T. medium) that are implicated in playing an important causative role in DD. This study was conducted to develop real-time PCR and loop-mediated isothermal amplification (LAMP) assays for the detection and differentiation of the three treponeme phylogroups associated with DD. The real-time PCR treponeme phylogroup assays targeted the 16S-23S rDNA intergenic space (ITS) for T. pedis and T. phagedenis, and the flagellin gene (flaB2) for T. medium. The 3 treponeme phylogroup LAMP assays targeted the flagellin gene (flaB2) and the 16S rRNA was targeted for the Treponeme ssp. LAMP assay. The real-time PCR and LAMP assays correctly detected the target sequence of all control strains examined, and no cross-reactions were observed, representing 100% specificity. The limit of detection for each of the three treponeme phylogroup real-time PCR and LAMP assays was ≤ 70 fg/μl. The detection limit for the Treponema spp. LAMP assay ranged from 7-690 fg/μl depending on phylogroup. Treponemes were isolated from 40 DD lesion biopsies using an immunomagnetic separation culture method. The treponeme isolation samples were then subjected to the real-time PCR and LAMP assays for analysis. The treponeme phylogroup real-time PCR and LAMP assay results had 100% agreement, matching on all isolation samples. These results indicate that the developed assays are a sensitive and specific test for the detection and differentiation of the three main treponeme phylogroups implicated in DD.

Rapid identification of Campylobacter-positive flocks before slaughter, following freezing and heat treatment for the Campylobacter-positive carcasses at the slaughterhouses is an effective control strategy against foodborne campylobacteriosis. We evaluated a loop-mediated isothermal amplification (LAMP) assay for the direct screening of naturally contaminated chicken cloacal swabs for Campylobacter jejuni/Campylobacter coli to compare this assay with conventional quantitative culture methods. In a comparison study of 165 broilers, the LAMP assay showed 82.8% (48/58 by conventional culture) sensitivity, 100% (107/107) specificity, 100% (48/48) positive predictive value (PPV), and 91.5% (107/117) negative predictive value (NPV). In a comparison of 55 flocks, LAMP showed 90.5% (19/21) sensitivity, 100% (34/34) specificity, 100% (19/19) PPV, and 94.4% (34/36) NPV. In the cumulative total of 28 farm-level comparisons, LAMP showed 100% (12/12) sensitivity, 100% (16/16) specificity, 100% (12/12) PPV, and 100% (16/16) NPV. The LAMP assay required less than 90 min from the arrival of the fecal samples to final results in the laboratory. This suggests that the LAMP assay will facilitate the identification of C. jejuni/C. coli-positive broiler flocks at the farm level or in slaughterhouses before slaughtering, which would make it an effective tool in preventing the spread of Campylobacter contamination.

Unstable behaviors of cellular premixed flames caused by hydrodynamic and diffusive-thermal instabilities under high- and low-temperature environment were studied numerically. Unsteady reactive flow was calculated in large space, based on the compressible Navier-Stokes equation including chemical reaction. As the unburned-gas temperature became higher (lower), the growth rate increased (decreased) and the unstable range widened (narrowed), which was due to the enlargement (reduction) of the burning velocity of a planar flame. On the other hand, the normalized growth rate decreased (increased) and the normalized unstable range narrowed (widened) under the high (low) temperature conditions. This was due to the weakness (strength) of thermal-expansion effects and to the reduction (enlargement) of Zeldovich numbers. Furthermore, unstable behaviors of cellular flames, i.e. the coalescence and divide of cells, appeared owing to hydrodynamic and diffusive-thermal instabilities. We found that the burning velocity of a cellular flame changed drastically with time, and the average burning velocity of a cellular flame normalized by that of a planar flame decreased (increased) as the unburned-gas temperature became higher (lower). In addition, the burning velocity of a cellular flame depended strongly on the space size. As the space size became larger, the burning velocity increased monotonously. This was because that the long-wavelength components of disturbances played a significant role in the dynamics of cellular premixed flames.

In this research, an inexpensive aerodynamic shape optimization of airfoil is performed for Darrieus type vertical axis wind turbine (VAWT). Computational fluid dynamics (CFD) evaluations of various airfoil shapes are treated inexpensively by considering the apparent flow velocity magnitudes and apparent angles of attack at multiple positions of VAWT airfoil, which includes some assumptions as two dimensional steady flows and no consideration about flow interactions between blade airfoils. Global optimal shapes are efficiently explored by using a Kriging response surface model approach. An optimal VAWT airfoil is obtained by the maximization of a proposed objective function. Since our objective function for this design optimization of VAWT airfoil can be primary decomposed into the terms of thrust force and pitching moment, another multi-objective optimization of thrust/pitching moment coefficients is also performed for detailed discussions about the obtained optimal airfoil. Analysis of variance is performed on the Kriging response surface model to extract design knowledge in this design optimization problem. The obtained optimal airfoil achieves a significant improvement in the aerodynamic performance compared with an existing airfoil. Finally, expensive unsteady CFD simulations are performed for the obtained airfoils, that take into account unsteady flow interactions between three blade airfoils. The results of the unsteady CFD simulations validate the effectiveness of the proposed aerodynamic shape optimization approach for VAWT airfoil.

In this research, unsteady particle image velocimetry (PIV) data are reconstructed / analyzed by a proper orthogonal decomposition (POD) with a cross validation approach. At unsteady PIV flow measurements we have interests, it is sometimes difficult to gather the PIV velocity vector in its entire flow field, mainly due to the lack of particles and/or low (even) contrasting density in the flow field. A POD-based gappy data reconstruction approach is applied to recover the gappy PIV data. The appropriate numbers of iterations as well as considering POD modes are determined by the cross validation approach. The PIV measurements are performed for the wake of a rectangular cylinder as well as for a self-developed flapping wing object. Especially in the case of the flapping wing object, the PIV measurement is performed at a hovering condition in which it is difficult to scatter the particles appropriately in its entire flow field. It results in the failures of PIV measurement at some regions of flow field, and then those incomplete PIV data are reconstructed by the developed approach. The flow/vortex structures can be discussed reasonably well by using the recovered PIV data.

In this research, a Gradient-Vector Product (GVP) enhanced Kriging response surface model approach has been developed in which the GVP is defined by the gradient vector of objective function with respect to design variables as well as an arbitral unit directional vector in design variable space. When two sample points are given closely in design variable space, the correlation matrix in the Kriging formulation becomes ill-conditioned, which results in the inaccuracy of the constructed response surface model. In this research, therefore, we try to treat the two functional data as one functional datum with one GVP datum in the Kriging formulation. The conventional Kriging formulation is extended to make use of the GVP information, and then a global design optimization system is proposed with the developed GVP-enhanced Kriging model approach. The validity of the developed approach is investigated in analytical function fitting/minimization problems as well as a 2D airfoil shape optimization problem. The performance of the developed GVP-enhanced model approach overcomes that of the conventional Kriging model approach when additional sample points are given closely to existing samples. The effectiveness and robustness of the developed response surface model approach are clearly demonstrated in this paper.

Speed is paramount in the diagnosis of highly infectious diseases, such as foot-and-mouth disease (FMD), as well as for emerging diseases; however, simplicity is required if a test is to be deployed in the field. Recent developments in molecular biology have enabled the specific detection of FMD virus (FMDV) by reverse-transcription loop-mediated isothermal amplification (RT-LAMP), real-time reverse-transcription polymerase chain reaction (RT-qPCR) and sequencing. RT-LAMP enables amplification of the FMDV RNA-dependent RNA polymerase 3D(pol) gene at 63 °C (in the presence of a primer mixture and both reverse transcriptase and Bst DNA polymerase) for 1 h, whilst RT-qPCR amplifies the same gene in approximately 2 h 30 min. In this study, we compared the sensitivity and effectiveness of RT-LAMP against RT-qPCR for the detection of the FMDV 3D(pol) gene in 179 oesophageal-pharyngeal scraping samples (collected by probang) obtained from clinically healthy cattle and buffalo in Malawi, Mozambique and Tanzania in 2010. The FMDV detection rate was higher with RT-LAMP (30.2%; n = 54) than with RT-qPCR (17.3%; n = 31). All samples positive by RT-qPCR (Cq ≤ 32.0) were also positive for the RT-LAMP assay; and both assays proved to be highly specific for the FMDV target sequence. In addition, the VP1 sequences of 10 viruses isolated from positive samples corresponded to the respective FMDV serotypes and genotypes. Our findings indicate that the performance of RT-LAMP is superior to RT-qPCR. Accordingly, we consider this test to have great potential with regard to the specific detection and surveillance of infectious diseases of humans and animals in resource-compromised developing countries.

In this study, we have developed a propulsion mechanism using a fin with variable effective length spring as variable stiffness mechanics. We measured its thrust and the lateral forces in water tank with three dimensional flow and that with quasi two dimensional environment. Additionally, three dimensional numerical analysis of the propulsion mechanism was performed. Flow field around the fin and variations of thrust and lateral forces obtained in this numerical analysis were compared with the above experimental results in the condition of rigid fin. As a result, there was a quantitative agreement between the experiments and numerical analyses. Because the computational costs of three-dimensional fluid-structure interaction analyses are very expensive, two dimensional fluid-structure interaction analyses were performed in the conditions of elastic fins. Qualitative agreement was observed between the fluid-structure interaction analyses and the above experimental results of quasi-two dimensional environment. In these conditions, an evaluated value of thrust efficiency increased with the decrease of the stiffness of the fin. The flow fields around the elastic fins were visualized to discuss the flow dynamics around the fin. From this result, it was shown that the direction of jet flow generated by vortex pair at the fin edge was closed to the rear direction of the propulsion mechanism by decreasing the stiffness of the fin.

In this research, a proper orthogonal decomposition (POD)-based re-parameterization approach is utilized to realize efficient multi-objective aerodynamic shape optimization (MOASO) by reducing the number of design variables, which results in reducing the number of computational fluid dynamics evaluations. The approach developed is examined in a three-dimensional wing-shape optimization problem of a supersonic transport configuration. As for the multi-objective design optimization problem, aerodynamic/sonic boom evaluations are performed to minimize the drag coefficient and sonic boom strength. By introducing a variable fidelity concept in the POD approach, the optimization problem can be solved with much smaller computational cost. Important design insights can be extracted and discussed from the most dominant (first) POD mode. [ABSTRACT FROM AUTHOR]