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During the last solar cycle a number of observations of solar radio emissions were made in a wide frequency range from which an enormous amount of information has been obtained. However the results obtained so far are limited by rather poor angular resolution. Observations with much higher resolution (of the order of 1′ arc) have been required for further studies of solar radio emissions. At the present stage such observations have proceeded in the microwave range; also the radioheliograph at 80 MHz has just started at the Culgoora Observatory. At the Tokyo Astronomical Observatory a high-resolution study of radio bursts in the metre-wave range has been planned since 1960, and the construction of a new compound interferometer operating at 160.3 MHz was started in April 1967 at a new site, Nobeyama. This site, located about 150 km north-west of Tokyo, is surrounded by mountains and quite free from man-made interference. We shall give a brief description of this equipment; details will be published later.
Meiotic maturation of oocytes requires a variety of ATP-dependent reactions, such as germinal vesicle breakdown, spindle formation, and rearrangement of plasma membrane structure, which is required for fertilization. Mitochondria are accordingly expected be localized to subcellular sites of energy utilization. Although microtubule-dependent cellular traffic for mitochondria has been studied extensively in cultured neuronal (and some other somatic) cells, the molecular mechanism of their dynamics in mammalian oocytes at different stages of maturation remains obscure. The present work describes dynamic aspects of mitochondria in porcine oocytes at the germinal vesicle stage. After incubation of oocytes with MitoTracker Orange followed by centrifugation, mitochondria-enriched ooplasm was obtained using a glass needle and transferred into a recipient oocyte. The intracellular distribution of the fluorescent mitochondria was then observed over time using a laser scanning confocal microscopy equipped with an incubator. Kinetic analysis revealed that fluorescent mitochondria moved from central to subcortical areas of oocytes and were dispersed along plasma membranes. Such movement of mitochondria was inhibited by either cytochalasin B or cytochalasin D but not by colcemid, suggesting the involvement of microfilaments. This method of visualizing mitochondrial dynamics in live cells permits study of the pathophysiology of cytoskeleton-dependent intracellular traffic of mitochondria and associated energy metabolism during meiotic maturation of oocytes.
Amorphous alloys have high tensile strength and easy soft magnetization, and are corrosion-resistant. As conventional amorphous alloy strips are mainly produced by the single rolling method, their thickness is less than 100 µm and their width is less than 200 mm. By combining ultra-rapid cooling, large-scale thermal spraying and warm rolling, the world’s first ever amorphous alloy strips were produced with thickness exceeding 300 µm and width exceeding 300 mm.
Diabetes predisposition is determined by pancreatic islet insulin secretion and insulin resistance. We studied female rat offspring exposed to low-protein maternal diet (50% control protein diet) in pregnancy and/or lactation at postnatal days 36, 110 and 450. Rats were fed either control 20% casein diet (C) or restricted diet (R – 10% casein) during pregnancy. After delivery, mothers received either C or R diet until weaning to provide four offspring groups: CC, RR, CR and RC (first letter denoting maternal pregnancy diet and the second lactation diet). Serum glucose, insulin and homeostatic model assessment (HOMA) were measured. Pancreatic islets were isolated and in vitro insulin secretion quantified in low glucose (5 mM) and high glucose (11 mM). Serum glucose, insulin and HOMA were similar in all groups at 36 and 110 postnatal days. HOMA was only higher in RR at 450 postnatal days. Only CC demonstrated differences in glucose sensitivity of β-cells to high and low doses at the three ages studied. At 36 days, RR, CR and RC and at 450 days RR and RC groups did not show glucose-stimulated insulin secretion differences between low and high glucose. Aging-associated glucose-stimulated insulin secretion loss was affected by maternal dietary history, indicating that developmental programming must be considered a major factor in aging-related development of predisposition to later-life dysfunctional insulin metabolism. Female offspring islets’ insulin secretion was higher than previously reported in males.
Corium which simulates the molten core of a Boiling Water Reactor was prepared as a parameter of Zr content, and melting temperatures and thermal conductivities were measured. The melting temperatures were measured by the thermal arrest method and were 2622 oC, 2509 oC and 2540 oC, respectively, in the specimens of 24.3 at%, 49.0 at% and 73.5 at% Zr content. Thermal conductivities had low values of 2.0-3.5 W/m oC at temperatures of 400 to 1600 oC.
In this study, sintered pellets were prepared from Zircaloy-2 oxide and UO2 as a parameter of content ratio (Zr contents were 0, 24.3, 49.0, 73.4, and 97.9 at% in metal). The sintered pellets were heated in 5%H2/Ar gas. UO2 pellets underwent simple thermal expansion caused by thermal vibration while Zircaloy-2 oxide pellets underwent thermal expansion and volume change with phase transformation. Finally, the 24.3, 49.0, and 73.5 at%Zr-UO2 pellet specimens showed both phenomena. However, phase transformation temperatures were lower than that of Zircaloy-2 oxide, and volume changes were much smaller. X-ray diffraction patterns obtained after thermal expansion measurements showed that the 24.3 at%Zr-UO2 specimen contained tetragonal and cubic (Zr, U)O2 while the 73.5 at%Zr-UO2 specimen contained mainly monoclinic ZrO2.
Maternal low-protein (LP) diets programme β-cell secretion, potentially altering the emergence of ageing of offspring pancreatic function. We hypothesised that isolated pancreatic islet β-cell secretory responses are blunted in offspring exposed to LP during development and age-related reduction is influenced by the developmental stage of exposure to decreased nutrition. We studied male offspring of rats fed control (C) or LP protein (R) diets in pregnancy, first letter and/or lactation second letter of CC, RR, CR or RC groups. Serum glucose, insulin and homeostatic model assessment (HOMA) were measured. Pancreatic islets were isolated and in vitro insulin secretion quantified in low (LG – 5 mm) or high glucose (HG – 11 mm). Body weight and serum values between groups were similar at all ages. Insulin and HOMA rose with age and were highest at postnatal day (PND) 450 in all groups. At PND 36, insulin secretion was greatest in RR and RC. Only CC increased insulin secretion to HG. By PND 110, restricted groups responded less to LG but increased secretion to HG. By PND 450, CC offspring alone increased secretion to HG. Despite minimal differences in circulating insulin and glucose, reduced maternal protein intake affected insulin secretion at all ages. In addition, ageing reduced function in all R groups compared with CC by PND 110 and further by PND 450 most markedly in RC. We conclude that maternal LP diet during pregnancy and/or lactation impairs offspring insulin secretory response to a glucose challenge and alters the trajectory of ageing of pancreatic insulin secretion.
We have already reported that Au or B doped SiGe amorphous thin films have superior thermoelectric properties which are attribute to amorphous phase. For the practical use, the bulk materials are required. In this work, we have tried and succeeded to fabricate Si-Ge-B amorphous bulk samples. First, fine particles were prepared by three kinds of mechanical process, such as roller milling method, mechanical alloying method and planetary milling method. It was intended to introduce a large amount of defects and strain into samples and/or gamorphouslization'h. Then, the prepared fine particles were pressed and formed into 2 x 5 x 15 mm^3 samples. Thermoelectric power and electrical resistivity of samples were measured by steady state measurement and four terminal method with temperature range of room temperature to 873 K in N2 flow at atmosphere pressure, respectively. Thermal conductivity was measured by photo-pyroelectric method in room temperature. Some samples have maximum value of thermoelectric power over 10-3 V/K. therefore≤ we were succeeded to prepare bulk materials which have higher thermoelectric power than that of conventional crystal materials. X-ray diffraction measurement and scanning electron microscope observation were performed on fabricated samples. From XRD measurement and SEM observation, the samples were in mixed condition of disordered microcrystals and amorphous state.
An ITO film on an SiO2 substrate was prepared from spin-coated nano-particles using a simple thermal process and photo irradiation process. The effects of the excimer lamp and excimer laser on the resistivity of the film were investigated. When the film is 40 nm thick, the combined two-step irradiation by an excimer lamp and laser in N2 is effective for the preparation of the ITO film with a lower resistivity. Using the two-step irradiation and one-step KrF irradiation in N2 at room temperature, the resistivity of the ITO film was 5.94×10−4Ωcm. On the other hand, when using the thermal process, the resistivity of the film sintered at 500 °C in N2 was 4.10×10−3Ωcm. The differences in resistivity are discussed on the basis of the microstructure using SEM, XRD and Hall measurements.
Propofol is reported to have protective effects on cerebral ischaemia-induced neuronal death. The aim of this study was to explore whether propofol and halothane can protect hippocampal neuronal function from ischaemic injury during general anaesthesia in rats.
Rats were divided into 2-vessel occlusion (incomplete cerebral ischaemia) and 4-vessel occlusion (complete cerebral ischaemia) groups consisting of three subgroups each (sham-operated, propofol and halothane groups). One hour after starting propofol 1 mg kg−1 min−1 with 30% O2 and N2 or halothane 0.8% in 30% O2 and N2 rats with or without bilateral vertebral artery occlusion had bilateral common carotid arteries occluded by vessel clips for 10 min. Anaesthesia was maintained for another 1 h. Seven days after ischaemia–reperfusion, hippocampal long-term potentiation in the perforant path–dentate gyrus synapse was determined as an index of cerebral outcome.
In the propofol groups, the formation of long-term potentiation was significantly impaired in the 2-vessel and 4-vessel occlusion groups compared to the respective sham-operated groups (P < 0.01 and P < 0.05, respectively). Impaired formation of long-term potentiation in propofol groups was comparable to that in halothane groups. The formation of long-team potentiation in the propofol and halothane 2-vessel group was not significantly different from that in the awake 2-vessel group.
Propofol and halothane administered during ischaemia do not possess protective effects against hippocampal neuronal dysfunction induced by cerebral ischaemia–reperfusion as evaluated by our transient ischaemic rat models.
The Clean Development Mechanism Project elaboration is reviewed,
considering every step from the project design document conception,
through validation, the approval by the national authorities and
the verification process.
The whole development is pioneered by CST ArcelorMittal Brasil,
aiming at carbon credits generation and GHG emission reduction.
An associated objective is the promotion of sustainable development.
The potential of carbon credits generation is estimated to be
440,263 tons of CO2 over a CDM project period of 10 years.
Coupled records of Sr/Ca and oxygen isotope ratios (δ18O) of coral skeletons have been used to produce quantitative estimates of paleo-sea surface temperature (SST) and δ18O of surface seawater that can in some cases be converted to sea surface salinity (SSS). Two fossil corals from Kikai Island in the subtropical northwestern Pacific, a location affected by East Asian summer and winter monsoons, were analyzed to investigate differences between mid-Holocene and present-day SST and SSS. At 6180 cal yr BP, SSTs were roughly the same as today, both in summer and winter; δ18Oseawater and SSS values were higher both in summer (+ 0.5‰, +1.1 psu) and in winter (+ 0.2‰, + 0.6 psu) than modern values. At 7010 cal yr BP, SSTs were slightly cooler both in summer and winter (−0.8 and −0.6 °C), whereas δ18Oseawater and SSS had higher values in summer (+ 0.3‰, + 0.6 psu) and in winter (+ 0.8‰, + 1.9 psu) than present-day values. These results are consistent with other marine records for the mid-Holocene of the low and midlatitudes in the northwestern Pacific. Such regional conditions indicate that the East Asian summer and winter monsoons were more intense in the mid-Holocene, which was likely a function of the mid-Holocene insolation regime.
Unusual non-human parasitic nematodes and eggs were detected in the faeces of an 8-year-old Japanese female suffering from Henoch-Schönlein purpura. The worms were adult female rhabditiform nematodes measuring 325.6–441.2 μm in length and 18.3–26.5 μm in width. One pair of the labia oris was notched with many spiny projections, while the other pair was strongly curved outwards. The worms were identified using light and scanning electron microscopy as the free-living nematode Diploscapter coronata (Cobb) based on their characteristic morphology. The patient's faeces containing worms and eggs were cultured using a filter-paper culture technique and after 7 days of culture, male as well as female worms were recovered. Worm survival time and hatchability of the eggs were examined in vitro after treatment with an artificial gastric or intestinal fluid. Although adult worms survived for less than one minute, eggs hatched after treatment with artificial gastric fluid. This suggests that eggs accidentally ingested or produced by adult D. coronata could develop in the human gastro-intestinal tract. Some morphological features of male D. coronata are also described.
We report U–Pb electron microprobe (zircon and monazite) and Secondary Ion Mass Spectrometry (SIMS) U–Pb (zircon) ages from a granulite-facies metapelite and a garnet–biotite gniess from Chittikara, a classic locality within the Trivandrum Block of southern India. The majority of the electron-microprobe data on zircons from the metapelite define apparent ages between 1500 and 2500 Ma with a prominent peak at 2109±22 Ma, although some of the cores are as old as 3070 Ma. Zircon grains with multiple age zoning are also detected with 2500–3700 Ma cores, 1380–1520 mantles and 530–600 Ma outer rims. Some homogeneous and rounded zircon cores yielded late Neoproterozoic ages that suggest that deposition within the Trivandrum Block belt was younger than 610 Ma. The outermost rims of these grains are characterized by early Cambrian ages suggesting metamorphic overgrowth at this time. The apparent ages of monazite grains from this locality reveal multiple provenance and polyphase metamorphic history, similar to those of the zircons. In a typical case, Palaeoproterozoic cores (1759–1967 Ma) are enveloped by late Neoproterozoic rims (562–563 Ma), which in turn are mantled by an outermost thin Cambrian rim (∼515 Ma). PbO v. ThO*2 plots for monazites define broad isochrons, with cores indicating a rather imprecise age of 1913±260 Ma (MSWD=0.80) and late Neoproterozoic/Cambrian cores as well as thin rims yielding a well-defined isochron with an age of 557±19 Ma (MSWD=0.82). SIMS U–Pb isotopic data on zircons from the garnet–biotite gneiss yield a combined core/rim imprecise discordia line between 2106±37 Ma and 524±150 Ma. The data indicate Palaeoproterozoic zircon formation with later partial or non-uniform Pb loss during the late Neoproterozoic/Cambrian tectonothermal event. The combined electron probe and SIMS data from the metapelite and garnet–biotite gneiss at Chittikara indicate that the older zircons preserved in the finer-grained metapelite protolith have heterogeneous detrital sources, whereas the more arenaceous protolith of the garnet–biotite gniess was sourced from a single-aged terrane. Our data suggest that the metasedimentary belts in southern India may have formed part of an extensive late Neoproterozoic sedimentary basin during the final amalgamation of the Gondwana supercontinent.
Based on a model of microstructure evolution, an appropriate rolling schedule
has been worked out to produce ultrafine grained steel (2 to 5 μm) on the hot strip mill.
This rolling schedule is characterized by a large reduction in the finishers followed by
strong cooling. Implementing such a rolling schedule on a conventional HSM raises major
problems: increased rolling torque and force, lowered crown and shape control, disturbed
looper control, accelerated roll damage, increased slip between strip and roll,
insufficient cooling efficiency. These problems have been solved on the new Nakayama
HSM by introducing innovative processes such as: single roll drive with different
diameter and a new CVC, curtain wall cooling in the finisher, low inertia hydraulic looper,
new high-speed steel rolls with solid lubrication.
Background and objective: The degradation of the cytoskeletal protein microtubule-associated protein 2 (MAP2), by calpain has been known to occur following traumatic brain injury. We examined the therapeutic potential of calpain inhibitor 2, compared with that of moderate hypothermia in traumatic brain injury produced by weight drop in rats.
Methods: An inhibitor treated group (n = 8) received calpain inhibitor 2 intravenously (i.v.) for 5 min before and for 6 h after injury (total 2 μmol); a hypothermic (HT) group (n = 8) was maintained at 30°C (temporalis muscle temperature) for 45 min prior to and 60 min after injury; an untreated (UT) group (n = 8) received an infusion of inactive vehicle. Eight rats (sham group) underwent surgery without brain injury. Histopathological (haematoxylin and eosin staining) and MAP2 (immunohistchemistry and western blotting) evaluations were performed at 6 h after injury.
Results: Ipsilateral cortical damage was marked in the injured groups. In the hippocampus, marked pyramidal neuronal damage was observed in the UT and calpain inhibitor treated (CI) groups, while these neurons were better preserved in the HT group. The hippocampal MAP2 levels in the UT, CI and HT groups were significantly decreased to 13 ± 9%, 28 ± 33% and 62 ± 25% of the sham control, respectively. MAP2 concentration in the HT group was significantly higher than in UT and CI groups (P < 0.05).
Conclusion: The results suggest that moderate hypothermia, but not calpain inhibitor 2 with the tested regime, attenuates cytoskeletal damage in the ipsilateral hippocampus at 6 h after traumatic brain injury.