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The aim of this research was to clarify the direct effects of a hot environment on ruminal motility in sheep fed twice a day. In the first experiment, in order to equalize variable factors excluding the ambient temperature between the thermoneutral environment (23°C, relative humidity 80%) and the hot environment (32°C, relative humidity 80%), sheep were fed equal amounts of the same quality feed twice a day. The sheep were allowed free access to water for the duration of the two one-hour feeding periods (10:00 am-11:00 am, 5:00 pm-6:00 pm). On the fourth day after exposure to the hot environment, the frequency and strength of ruminal contractions were continuously recorded between 9:30 am and 11:00 pm. Prior to the exposure to a hot environment the frequency and strength of ruminal contractions were recorded in a thermoneutral environment during the period 9:30 am-11:00 pm. In the second experiment, in order to maintain the stomach content of the sheep at equal levels in both environments, the sheep were fed equal amounts of the same quality feed twice a day. Following the completion of the two one-hour feeding periods, a fixed amount of warm water was infused into the rumen. Rumen motility was then recorded during the same period as for the first experiment (9:30 am-11:00 pm). In the first experiment, when the frequency of ruminal contractions prior to (24, 24 frequency/15 min), during (48, 47 frequency/min) and after (22, 19 frequency/min) both the morning and afternoon feeding in a hot environment was compared with the values from the thermoneutral environment (20, 22; 50, 50; 21, 20 frequency/min), there was found to be no difference. However, the strength of ruminal contractions after morning and afternoon feeding (3.7, 3. 1 mm Hg) in the hot environment decreased significantly in comparison with the thermoneutral environment (4.3, 3.8 mm Hg). In the second experiment, the frequency of ruminal contractions in the hot environment was not significantly different from that in the thermoneutral environment. The strength of ruminal contractions after ruminal infusion of warm water in the hot environment (morning: 4.6, afternoon: 4.5 mm Hg) was significantly lower than that in the thermoneutral environment (morning: 5.6, afternoon: 5.0 mm Hg). The results suggest that a hot environment acts directly on the strength of ruminal contractions in sheep fed twice a day rather than on the frequency.

We present observations of the 3P1-3P0 fine structure transition of atomic carbon [CI], the J=3-2 transition of CO, as well as of the J=1-0 transitions of 13CO and C18O toward DR15, an HII region associated with two mid-infrared dark clouds (IRDCs). The 13CO and C18O J=1-0 emissions closely follow the dark patches seen in optical wavelength, showing two self-gravitating molecular cores with masses of 2000 Msun and 900 Msun, respectively, at the positions of the catalogued IRDCs. Our data show a rough spatial correlation between [CI] and 13CO J=1-0. Bright [CI] emission occurs in relatively cold gas behind the molecular cores, neither in highly excited gas traced by CO J=3-2 emission nor in HII region/molecular cloud interface. These results are inconsistent with those predicted by standard photodissociation region (PDR) models, suggesting an origin for interstellar atomic carbon unrelated to photodissociation processes., Comment: 11 pages Latex, 6 figures, Accepted for publication in The Astrophysical Journal

The 3P2-3P1 fine-structure line of the neutral carbon atom (809 GHz) has been observed toward the Orion Kleinmann-Low (KL) region with the Mount Fuji submillimeter-wave telescope. The 6' × 6' area centered at Orion KL has been mapped with a grid spacing of 15. The intensity distribution of the 3P2-3P1 line is found to be similar to that of the 3P1-3P0 line; these lines are rather weak toward Orion KL, while they are both bright at Orion KL's northern and southern positions. The excitation temperature determined from the intensity ratio between the 3P2-3P1 and 3P1-3P0 lines ranges from 40 to 110 K. The excitation temperature is not enhanced toward Orion KL, whereas it tends to be high in the vicinity of θ1 Orionis C. These results indicate that the C I emission arises from a photodissociation surface illuminated by strong UV radiation from θ1 Ori C. The relative reduction in the C I intensities toward Orion KL is found to originate from a relatively low excitation temperature rather than from the depletion of the C I column density. The origin of the low-excitation temperature of C I toward Orion KL is discussed in terms of a radiative transfer effect.

We have developed a 1.2 m submillimeter-wave telescope at the summit of Mt. Fuji to survey emission lines of the neutral carbon atom ( C I ) toward the Milky Way. A superconductor-insulator-superconductor mixer receiver on the Nasmyth focus is used to observe the 492 GHz band in SSB and the 345 GHz band in DSB simultaneously. The receiver noise temperature is 300 K in SSB and 200 K in DSB for 492 and 345 GHz, respectively. The intermediate frequency frequency is 1.8–2.5 GHz. An acousto-opticalspectrometer which has the total bandwidth of 0.9 GHz and 1024 channel outputs has also been developed. The telescope was installed at the summit of Mt. Fuji (alt. 3725 m) in July 1998. It has been remotely operated via a satellite communication system from Tokyo or Nobeyama. Atmospheric opacity at Mt. Fuji was 0.4–1.0 at 492 GHz during 30% of the time and 0.07–0.5 at 345 GHz during 60% of the time from November 1998 to February 1999. The system noise temperature was 1000–3000 K in SSB at 492 GHz and 500–2000 K in DSB at 345 GHz. We observed the CI ( 3 P 1 − 3 P 0 : 492 GHz) and CO (J=3−2: 345 GHz) emission lines from nearby molecular clouds with the beam size of 2.2 and 3.1, respectively. We describe the telescope system and report the performance obtained in the 1998 winter.

Large scale mapping observations of the 3P1-3P0 fine structure transition of atomic carbon (CI, 492 GHz) and the J=3-2 transition of CO (346 GHz) toward the Orion A molecular cloud have been carried out with the Mt. Fuji submillimeter-wave telescope. The observations cover 9 square degrees, and include the Orion nebula M42 and the L1641 dark cloud complex. The CI emission extends over almost the entire region of the Orion A cloud and is surprisingly similar to that of 13CO(J=1-0).The CO(J=3-2) emission shows a more featureless and extended distribution than CI.The CI/CO(J=3-2) integrated intensity ratio shows a spatial gradient running from the north (0.10) to the south (1.2) of the Orion A cloud, which we interpret as a consequence of the temperature gradient. On the other hand, the CI/13CO(J=1-0) intensity ratio shows no systematic gradient. We have found a good correlation between the CI and 13CO(J=1-0) intensities over the Orion A cloud. This result is discussed on the basis of photodissociation region models.

A distribution of the neutral carbon atom (C i) in Heiles cloud 2 (HCL2) has been investigated with the Mount Fuji submillimeter-wave telescope. A region of 1.2 deg 2 covering a whole region of HCL2 has been mapped with the 3 P1‐ 3 P0 fine-structure line (492 GHz) of C i. The global extent of the C i emission is similar to that of 13 CO, extending from southeast to northwest. However, the C i intensity is found to be rather weak in dense cores traced by the line of C 18 O. On the other hand, strong C i emission is observed in a south part of J= 1‐0 HCL2 in which the C 18 O intensity is fairly weak. The C i/CO abundance ratio is greater than 0.8 for the C i peak, whereas it is 0.1 for the dense cores such as the cyanopolyyne peak. The C i‐rich cloud found in the south part may be in the early evolutionary stage of dense core formation where C i has not yet been converted completely into CO. This result implies that formation of dense cores is taking place from north to south in HCL2. Subject headings: ISM: atoms — ISM: clouds — ISM: evolution — ISM: individual (Heiles’s cloud 2)

Accepted: 1999-06-14, 資料番号: SA1002255000

We propose an integrated, comprehensive network-inferring system for genetic interactions, named VoyaGene, which can analyze experimentally observed expression profiles by using and combining the following five independent inferring models: Clustering, Threshold-Test, Bayesian, multi-level digraph and S-system models. Since VoyaGene also has effective tools for visualizing the inferred results, researchers may evaluate the combination of appropriate inferring models, and can construct a genetic network to an accuracy that is beyond the reach of a single inferring model. Through the use of VoyaGene, the present study demonstrates the effectiveness of combining different inferring models.

We report on submillimeter-wave and millimeter-wave observations toward supernova remnants (SNRs) by using the James Clerk Maxwell Telescope, the Mt. Fuji submillimeter-wave telescope, and the Nobeyama 45-m radio telescope. For the supernova remnant W28, which is an EGRET gamma-ray source, we have convincingly detected the broad CO, HCO+, HCN, and SiO emission lines from the shock-accelerated gas due to the SNR-cloud interaction. The previously-reported 1720-MHz OH maser spot is found to be located at the shock front. By using the Mt. Fuji submillimeter-wave telescope, we observed the 492-GHz CI (neutral atomic carbon), 345-GHz CO (3–2) and 330-GHz 13CO (3–2) emission toward SNRs, W44 and W51B/C. We found that the CI/CO and CI/13CO intensity ratio tends to be high in the SNR-cloud interaction region in W51B/C SNR. This fact might suggest the CI relative abundance is enhanced by the interaction, not only in the SNR IC 443, but also in W51B/C SNR.

The Mt. Fuji submillimeter-wave telescope has been operated since November 1998 to survey neutral atomic carbon (CI) toward the Milky Way. It has a 1.2 m main reflector with a surface accuracy of 10 micrometer in rms. A dual polarization superconductor-insulator-superconductor (SIS) mixer receiver mounted on the Nasmyth focus receives 810/492/345 GHz bands in DSB simultaneously. An acousto-optical spectrometer (AOS) has 1024 channels for 0.8 GHz bandwidth. The telescope was installed with a helicopter and bulldozers at the summit of Mt. Fuji (alt. 3725 m) in July 1998 after a test operation at Nobeyama for a year. It has been remotely operated via a satellite communication from Tokyo or Nobeyama. Atmospheric opacity at Mt. Fuji was 0.4 - 1.0 at 492 GHz in 30% of time and 0.07 - 0.5 at 345 GHz in 60% of time during winter five months. The system noise temperature was typically 1200 K (SSB) at 492 GHz and 500 K (DSB) at 345 GHz. The beam size was measured to be 2.'2 and 3.'1 at 492 and 345 GHz, respectively. We have conducted a large-scale survey of the CI (492 GHz) and CO (3 - 2: 345 GHz) emission from nearby molecular clouds with total area of 10 square degrees. We describe the telescope system and report the performance obtained in the 1998 winter.

Supernova remnants (SNRs), which are very energetic objects, are thought to have great influence on the interstellar medium. The expanding shock waves of SNRs compress, heat, and accelerate the interstellar gas. Because the interaction of SNR with the molecular cloud may play an important role in the next-generation star for- mation, it is of considerable interest to study the physical and chemical processes of the interaction.In order to search for the interaction between SNR and the molecular cloud, we observed two SNRs, W28 and γ Cygni SNR, which are supposed to be EGRET gamma- ray sources, in submillimeter-wave CO ( J = 3 - 2 ) line (345 GHz; 0.9 mm) by using the 15 m James Clerk Maxwell Telescope (JCMT). In W28, we detected a broad emission (maximum linewidth reaches ΔV ～70kms-1), which suggests an interaction between SNR and the molecular cloud (“shocked gas”), as well as a narrow emission from the “unshocked gas”. However, the broad emission was not observed toward γCygni SNR.For W28, the distribution of the CO gas is similar to that of the 327 MHz radio- continuum emission, and tends to be stronger along the radio-continuum ridge. This suggest that the compression of magnetic fields in the SNR by the cloud results in enhanced synchrotron radiation. In addition, all of the OH (1720 MHz) maser spots, which trace the interaction between SNR and the molecular cloud, are located along the filament of the shocked gas. These facts convincingly indicate that SNR W28 interacts with the molecular cloud. Our observations are consistent with a hypothesis that the interaction of the SNR with the molecular cloud can be the origin of gamma-rays. Moreover, the distribution of the unshocked and shocked gas is clearly resolved. The shocked gas is filamentary, and surrounds the center of the supernova, explosion. The unshocked gas is displaced by 0.4 - 1.0 pc outward with respect to the shocked gas. The spatial relationship between shocked and unshocked gas has been clarified for the first time for the interaction between SNRs and molecular clouds.In order to obtain the distribution of the cold gas and the physical properties of the molecular gas associated with W28, we observed the millimeter-wave CO (J=1 - 0 ) line (115 GHz ; 2.6 mm) by using the 45 m telescope of the Nobeyama Radio Observatory (NRO). It is found that the line intensity of CO (J=1 - 0 ) emission is stronger than that of CO (J=3 - 2) emission in the narrow component, and while the CO (J=3 - 2) emission is stronger than CO (J =1 - 0) emission in the broad component. The distribution of CO (J =1 - 0) globally resembles that of CO (J = 3 - 2 ). The unshocked gas has a gas kinetic temperature of Tkin ～20 K and a density of n(H2) ～ 10 3 cm-3, and a total mass of Munshocked = 4 × 103 M〓. On the other hand, the shocked gas has Tkin > 60 K, n(H2) > 104 cm-3, and Mshocked = 2 × 103 M〓. The total kinetic energy deposited in the shocked molecular gas is 3 × 1048 erg, which corresponds to 0.3 % of the energy of the supernova explosion.To understand the chemistry related to carbon in the interaction region between SNR and the molecular cloud, we observed in CO(J=3-2) at 345 GHz(0.9 mm) and CI(3P1 - 3P0) at 492 GHz (0.6 mm) toward the four SNRs, W28, IC443, W44, and W51C by using the Mt. Fuji submillimeter-wave telescope, which we developed. This telescope is the first submillimeter-wave telescope in Japan. With this telescope, we can observe CI(3P1 - 3P0) and CO(J=3 - 2) simultaneously. The spatial resolution is suitable for the observation of the molecular cloud scale. Except for IC 443, the CI(3P1 - 3P0) emission was detected. We found that the distribution of the CI(3P1 - 3P0) emission is similar to that of the CO(J=3 - 2) emission. It is clear that the known OH[(1720 MHz) maser spots are located at the edge of clumps in all 4 SNRs. In the interaction region between SNR and the molecular cloud, the CI(3P1 - 3P0)/CO(J=3 - 2) peak intensity ratio and the N(CI)/N(CO) column density ratio tend to be high. On the other hand, in molecular clouds unrelated with SNR, the ratios are lower. This result might imply that the interaction of SNR with the molecular cloud enhances the CI abundance.At present, though 220 SNRs are cataloged in our Galaxy, the observational examples of the interaction between SNR and molecular clouds are small in number. The shock region in W28 has rather simple structure and “edge-on”. In the future, W28 can be one of the best regions for detailed studies of the interaction between SNR and the molecular cloud. By increasing the number of the observational examples, we can obtain better understanding of the molecular cloud associated with SNR.