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We investigate the one-dimensional non-relativistic Weibel instability through the capture of anisotropic pressure tensor dynamics using an implicit 10-moment fluid model that employs the electromagnetic Darwin approximation. The results obtained from the 10-moment model are compared with an implicit particle-in-cell simulation. The linear growth rates obtained from the numerical simulations are in good agreement with the theoretical fluid and kinetic dispersion relations. The fluid dispersion relations are derived using Maxwell’s equations and the Darwin approximation. We also show that the magnetohydrodynamic approximation can be used to model the Weibel instability if one accounts for an anisotropic pressure tensor and unsteady terms in the generalised Ohm’s law. In addition, we develop a preliminary theory for the saturation magnetic field strength of the Weibel instability, showing good agreement with the numerical results.
The Institute of Translational Health Sciences (Clinical and Translational Science Awards Program hub) developed a program coined Community Voices to invite communities to submit project ideas and be matched with academic researchers. We describe formative research to understand community and academic researcher perspectives on how the program could facilitate collaborations addressing community priorities.
Methods:
We conducted four focus groups with 31 community-based organization (CBO) representatives and 11 semi-structured interviews with academic researchers in the Washington, Wyoming, Alaska, Montana, and Idaho regions. Questions included the appeal of Community Voices to engage community and academic partners, potential program usefulness, and Community Voices’ potential role in building community–academic partnerships. We used an inductive, constant comparison approach to code transcripts and thematic analysis to generate themes.
Results:
Most CBO representatives were female (87.1%) and Hispanic/Latino (61.3%). Most academic researchers had a PhD (63.6%) and worked at a university (81.8%). The themes were: (1) community–academic partnerships built on trust will offer mutual benefit, (2) community-initiated project ideas should prioritize community needs, (3) matchmaking will accelerate connections but should not replace time to foster partnership, (4) Community Voices should go beyond matchmaking and provide ongoing support/training, and (5) fostering effective communication is key to partnership success.
Conclusions:
Community Voices is a novel, bidirectional community engagement program model that advances current practices of prioritizing researchers’ project ideas. This community-driven program may shift the future direction of community engagement practices where prioritizing community’s ideas becomes the norm of community–academic partnerships in clinical and translational science.
In this paper the Very High Energy (VHE) gamma-ray astronomy program at the University of Adelaide is described. VHE gamma rays with energies above ~5 × 1011eV are observed using the atmospheric Cerenkov technique. Results from the first three years observations at Woomera and the current upgrading of the telecope are described. The CANGAROO project, a collaboration between the University of Adelaide and a number of Japanese institutions, is also introduced.
A fully coherent free electron laser (FEL) seeded with a higher-order harmonic (HH) pulse from high-order harmonic generation (HHG) is successfully operated for a sufficiently prolonged time in pilot user experiments by using a timing drift feedback. For HHG-seeded FELs, the seeding laser pulses have to be synchronized with electron bunches. Despite seeded FELs being non-chaotic light sources in principle, external laser-seeded FELs are often unstable in practice because of a timing jitter and a drift between the seeding laser pulses and the accelerated electron bunches. Accordingly, we constructed a relative arrival-timing monitor based on non-invasive electro-optic sampling (EOS). The EOS monitor made uninterrupted shot-to-shot monitoring possible even during the seeded FEL operation. The EOS system was then used for arrival-timing feedback with an adjustability of 100 fs for continual operation of the HHG-seeded FEL. Using the EOS-based beam drift controlling system, the HHG-seeded FEL was operated over half a day with an effective hit rate of 20%–30%. The output pulse energy was $20~{\rm\mu}\text{J}$ at the 61.2 nm wavelength. Towards seeded FELs in the water window region, we investigated our upgrade plan to seed high-power FELs with HH photon energy of 30–100 eV and lase at shorter wavelengths of up to 2 nm through high-gain harmonic generation (HGHG) at the energy-upgraded SPring-8 Compact SASE Source (SCSS) accelerator. We studied a benefit as well as the feasibility of the next HHG-seeded FEL machine with single-stage HGHG with tunability of a lasing wavelength.
Using a newly developed rapid test, an outbreak of human metapneumovirus (HMPV) infection in a long-term care facility was detected within only 2 days after the onset of symptoms in a putative index case. The outbreak was almost under control within 8 days mainly by zoning patients, with the exception of two cases of HMPV that were diagnosed 16 and 17 days after the onset of the outbreak. According to an immunological diagnosis as well as the rapid test, it was eventually proven that 18 patients had HMPV infections. We suspected that even asymptomatic residents, who had not been completely separated from the facility population, were a source of infection. That suggested that all asymptomatic residents should be tested and that the separation of the infected patients should be absolute, if an outbreak of HMPV infection is suspected in such a facility.
A solar eclipse is one of the most popular events in astronomy. Although it is the single astronomical event, it gives different images from place to place and changes in time. It is the most important message from astronomy to the public that an apparent face depends on the viewpoint and we should get the comprehensive view.
Laboratory studies showed that elm leaf beetle, Pyrrhalta luteola (Müller), larvae and pupae were susceptible to the nematode Neoaplectana carpocapsae Weiser; adults were less likely to be infected because of their dispersal ability. Spruce budworm, Choristoneura occidentalis Freeman, larvae were susceptible to the nematode in the laboratory. Field application of the nematode in 2% aqueous Volck oil suspension against elm leaf beetle or spruce budworm larvae did not significantly reduce the populations when compared with controls. Desiccation of the infective nematodes may be a factor in the variable results for elm leaf beetle, and cool temperatures and rain may have been factors in the poor results for spruce budworm. However, significant population reduction occurred in nematode treatments against elm leaf beetle pupae in litter. This nematode may be used against beetle pupae in conjunction with other control tactics.
Kyushu University has installed the hard X-ray beamline, BL06, at bending magnet source of SAGA Light Source in Japan. It is designed for X-ray absorption fine structure (XAFS) spectroscopy and small-angle X-ray scattering (SAXS) experiments. The X-ray energy covered by the beamline ranges from 2.1 to 23 keV using a Si(111) flat double-crystal monochromator. Two bent cylindrical-type focusing mirrors are used, each with a different focal point. They are set in the optics section and can be used independently. One of the mirrors has a focal distance of 6 m, which corresponds to the sample stage for XAFS experiments, while the second mirror focuses at 10 m, corresponding to the detector for the SAXS experiments. The photon flux measured by the ion chamber at mirror focal point is 1010 phs/s. The experimental hutch houses the detection equipment for both XAFS and SAXS. For XAFS studies, a set of ion chambers for transmission mode and a Lytle detector and a Si drift detector for fluorescence yield mode are available. For SAXS studies, the camera pass length can be chosen from 0.5 to 2.5 m with 0.5 m increments in between, and an image plate is operated as signal detector. The beamline will be opened for user operation around summer 2010.
Intake of a small dose of foodborne pathogens can cause infection. In this study, an estimation of the infectious dose of the pathogens was obtained by conducting microbiological risk assessments. The contamination levels of foodborne pathogens were analysed in 17 outbreaks of Salmonella, Escherichia coli O157, enterotoxigenic E. coli, Vibrio parahaemolyticus, and Campylobacter jejuni occurring in Japan between 2004 and 2006. The infectious dose was estimated in 14 of the 17 outbreaks utilizing existing data. In three outbreaks of Salmonella infection in which the infection rate was 89–100%, the dose of the ingested pathogens was estimated to be 259 000–14 000 000 000 c.f.u. In other outbreaks of Salmonella infection, the infection rate and dose of the ingested pathogens were 10–66·4% and 81–1560 c.f.u. or most probable number (MPN), respectively. The ingested Salmonella dose is likely to be related to the infection rate; however, storage conditions should be taken into account when making this determination. In an outbreak of E. coli O157 infection, the infection rate and ingestion dose were 100% and 2 to <9 c.f.u., respectively, while in an outbreak of enterotoxigenic E. coli infection, they were 93% and 25–1000 c.f.u., respectively. Finally, in an outbreak of C. jejuni infection, the infection rate and ingestion dose were 37·5% and 360 MPN, respectively. These results will be particularly valuable for risk assessment.
The FSBA (Flexible Shaft Backing Assemblies) has been developedfor a 20-high Sendzimir mill. This new shape control actuator wassupported by a shape analysis model based on the distribution ofgeometrical moment of inertia in the roll axial direction. The shapecontrol range was doubly extended by the introduction of FSBA. Itwas confirmed on an industrial mill that quarter buckles are suppressedunder a wide range of rolling conditions by shape control withFSBA and concave rolls.
Vibrio parahaemolyticus and Vibrio vulnificus were isolated from faecal samples of wild aquatic birds in winter. Although V. parahaemolyticus and V. vulnificus were present in low numbers in seawater in the area where the faecal samples of the birds were collected, the pathogens were isolated from the faeces of the birds. This study demonstrates that wild aquatic birds are a vehicle for V. parahaemolyticus and V. vulnificus to survive in winter.
Mechanical characterizations using nanoindentation technique were performed for the martensitic steel used as practical dies steel containing carbide-former elements of Cr, Mo, W, and V, which are responsible for secondary hardening by tempering. The nanohardness Hn corresponding to the matrix strength shows obvious secondary hardening, and the hardening-peak temperature coincides with that of the macroscale hardness Hv. By comparing the temper-softening behavior of the high-purity Fe–C binary martensite, the ratio of the nanohardness Hn of the dies steel to that of the Fe–C binary steel is approximately a factor of two, whereas the same ratio of the macroscopic hardness Hv is three at the secondary-hardening peak. These results suggest that the secondary hardening of the dies steel during tempering is attributed not only to the nanoscale strengthening factors such as precipitation hardening by the alloy carbides, but also to some other factors in larger scale. One of the strengthening factors in larger scale is a decomposition of 9% retained austenite to much harder phases, such as martensite and/or ferrite–cementite constituent.
The relationship between the nanohardness and the microstructures in the Fe–C martensite was studied to understand the contributions of the matrix and the grain boundary to the macroscopic strength. As-quenched martensite was examined for five kinds of Fe–C alloys with various carbon contents in the range of 0.1–0.8 mass%, while quench-tempered martensite was investigated for an Fe–0.4% C alloy. The ratio of the nanohardness to the macrohardness Hn/Hv was much smaller for the Fe–C martensite than those for the single crystals, indicating that there is a significant grain-boundary effect for the martensite. The ratio Hn/Hv of the as-quenched martensite decreased with an increase in the carbon content since the size of the block structure decreased with increasing carbon content. For the quench-tempered specimens, a significant reduction of the grain-boundary effect occured at the tempering temperature of 723 K. It is mainly due to the depression of the locking parameter caused by the disappearance of the film-like carbides on the boundaries.
We have investigated current-voltage characteristics of individual CdSe colloidal nanodots by conductive-tip atomic force microscopy (AFM). The colloidal nanodots were spun-coat and scattered on a self-assembled monolayer of thiophene molecules formed on Au (111) surfaces for single dot measurements. A thin SiO2 layer was deposited on the sample surface in order to prevent the dots being moved by the tip during measurement. We imaged the topography of isolated single dots by AFM operated in contact mode, and measured current-voltage characteristics with the conductive tip positioned on single dots; large conductivity changes which suggest resonant tunneling through a quantized energy level in the dot was observed even at room temperature.
Japanese Black cattle (Wagyu), deposit much higher amounts of intramuscular fat, known as marbling, than other breeds of cattle. To determine whether this unique fat deposition is attributable to the somatotropic axis, we compared pulsatile growth hormone (GH) secretion, plasma levels of insulin-like growth factor-1 (IGF-1) and cellular density of somatotrophs (GH-expressing cells) in the anterior pituitary glands of Japanese Black and Holstein steers. Blood samples were withdrawn every 15 min for 6 h from 14 Japanese Black and 12 Holstein steers at about 17 months of age, and GH and IGF-1 concentrations were determined. The distribution and proportion of GH-expressing cells were analysed by immunohistochemistry combined with point-count morphometry in pituitaries from six steers from each breed aged about 18 to 21 months. Overall mean and baseline plasma GH concentrations were lower (P < 0·001) in Japanese Black than Holstein steers. In addition, Japanese Black had smaller (P < 0·05) amplitudes of GH secretory pulses than Holstein steers, whereas the GH pulse frequency did not differ between the breeds. Japanese Black steers also had lower (P < 0·001) plasma levels of IGF-1 than Holstein steers. The marbling score of Japanese Black steers was higher (P < 0·001) than that of Holsteins at the same carcass weight. The proportion of GH-expressing cells was smaller (P < 0·05) in Japanese Black than Holstein steers at the hind dorsal and hind ventral regions of the adenohypophysis. Thus, in Japanese Black and Holstein steers, the breed difference in the relative density of GH-expressing cells corresponded to that in profiles of pulsatile GH secretion. These results suggest that the features of the somatotropic axis intrinsically differ between Japanese Black and Holstein cattle and that these features may be partly responsible for the genetic ability of the former to deposit greater amounts of marbling fat and for the smaller frame of Wagyu cattle.
The hypotensive and vasorelaxing peptides adrenomedullin (AM) and its gene-related peptide, proadrenomedullin N-terminal 20 peptide (PAMP), were found to be distributed on the surface of the colonic mucosa. AM and PAMP showed dose-dependent antimicrobial activity against E. coli. The results suggest that the novel vasoactive peptides AM and PAMP play an important role in mucosal defence. Experimental Physiology (2001) 86.5, 543-545.
Background and objective To investigate the effects of the perineural injection of lidocaine or corticosteroids on radicular blood flow during spinal surgery.
Methods After lumbar discectomy, a probe for laser Doppler flowmetry was placed directly on the 4th or 5th lumbar nerve root. Thirty patients undergoing lumbar discectomy were randomly assigned to one of three groups. Each group received one of three protocols for a perineural injection to the nerve root: 1.0 mL 0.9% saline in group A, 1.0 mL 1% lidocaine in group B or 1.0 mL dexamethasone (4 mg) in group C. Measurements included radicular blood flow, mean arterial pressure, haemoglobin concentration, percutaneous oxygen saturation and end-tidal carbon dioxide tension. Radicular blood flow was measured by laser Doppler flowmetry before the injection and 15 min after these injections. The three groups were similar with respect to mean arterial pressure, haemoglobin concentration, percutaneous oxygen saturation and end-tidal carbon dioxide tension.
Results Radicular blood flow did not change after the injection in any of the groups.
Conclusions The results suggest that the perineural injection of 1% lidocaine or dexamethasone does not affect radicular blood flow during lumbar discectomy.
We investigated the effects of controlled hypotension with haemodilution under isoflurane anaesthesia on splanchnic perfusion in elderly patients. We determined the intramucosal pH using gastric tonometry in 28 patients scheduled for hip surgery. Patients without cardiac disease were assigned to two groups according to age. Group A (adult patients, n=14) included patients aged less than 60 years (range 29–58 years, 47±11 years, mean±SD) and group B(elderly patients, n=14) more than 65 years (68–78 years, 72±5 years). Anaesthesia was maintained with N2O-O2-isoflurane. After induction of anaesthesia, haemodilution was produced by drawing 800–1000 mL of blood and replacing it with the same amount of hydroxyethyl starch. Final haematocrit values were 23–24% in all groups. Controlled hypotension was induced with prostaglandin E1 (PGE1) and mean blood pressure was maintained at approximately 60 mmHg for approximately 80 min. Measurements, including gastric intramucosal pH (pHi), arterial blood pH (pHa) and serum lactate were measured before haemodilution (T0), after haemodilution (T1), 80 min after starting hypotension (T2), 60 min after recovery from hypotension (T3) and on the 1st post-operative day (T4). The values of pHa and lactate showed no change in the groups throughout the time course. The gastric pHi values showed significant decreases from 7.418±0.035 to 7.334±0.024 (P < 0.05) in group A and from 7.428±0.029 to 7.320±0.039 (P < 0.05) in group B after haemodilution, while no further decreases were found at 80 min after starting the hypotension (7.329±0.038 in group A and 7.322±0.031 in group B) and 60 min after recovery from hypotension (7.331±0.029 in group A and 7.328±0.034 in group B). It can be concluded that moderate haemodilution under isoflurane anaesthesia might impair splanchnic perfusion in adult and elderly patients. The addition of controlled hypotension with PGE1 or an increase in age did not further impair splanchnic perfusion nor the splanchnic oxygen supply.