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Root microbiomes are established through selective recruitment by host plants from pools of potential partners. However, the assembly rules of root microbiomes remain unclear. To elucidate (i) the effects of host plant phylogeny on root microbiome assembly and (ii) which microbial groups affect differences in root microbiome assemblies, the structures of bacterial and fungal root microbiomes from 20 cultivated angiosperms were compared. Surface-sterilized seeds from each species were sown in identical soil, and DNA was extracted from the plant roots after 7-8 weeks. The bacterial (16S rRNA) and fungal (ITS) communities were then examined using Illumina MiSeq. The phylogenetic distances of host plants and assembly dissimilarities of bacterial microbiomes, but not of fungal ones, were significantly correlated, as were the topologies of the host plant phylogenetic tree and the community dissimilarity tree, thereby confirming the phylogenetic conservation of bacterial root microbiomes. Furthermore, host plant phylogeny mainly affected only a few specific bacterial lineages, including the Betaproteobacteria, Gammaproteobacteria, and Chloroflexi. Burkholderia (Betaproteobacteria) taxa were more abundant in monocots than in dicots, whereas Streptomyces (Actinobacteria) taxa were less abundant. These findings suggest that bacterial root microbiomes have significantly contributed to the functional divergence of angiosperms at higher taxonomic levels.

Microbial diversity in an apple orchard cultivated with natural farming practices for over 30 years was compared with conventionally farmed orchards to analyze differences in disease suppression. In this long-term naturally farmed orchard, major apple diseases were more severe than in conventional orchards but milder than in a short-term natural farming orchard. Among major fungal species in the phyllosphere, we found that Aureobasidium pullulans and Cryptococcus victoriae were significantly less abundant in long-term natural farming, while Cladosporium tenuissimum predominated. However, diversity of fungal species in the phyllosphere was not necessarily the main determinant in the disease suppression observed in natural farming, instead, the maintenance of a balanced, constant selection of fungal species under a suitable predominant species such as C. tenuissimum seemed to be the important factors. Analysis of bacteria in the phyllosphere revealed Pseudomonas graminis, a potential inducer of plant defenses, predominated in long-term natural farming in August. Rhizosphere metagenome analysis showed that Cordyceps and Arthrobotrys, fungal genera are known to include insect- or nematode-infecting species, were found only in long-term natural farming. Among soil bacteria, the genus Nitrospira was most abundant, and its level in long-term natural farming was more than double that in the conventionally farmed orchard.

To elucidate the natural clinical course and identify radiological changes of non-hemorrhagic dissecting aneurysm, we retrospectively reviewed the cases of 10 patients with non-hemorrhagic dissecting aneurysms. Their clinical course had been followed for 1 month to 11 years 7 months (mean: 3 years 2 months), and cerebral angiography and/or magnetic resonance (MR) angiography findings examined for 3 weeks to 10 years 1 month after initial onset. The site of the dissection involved 8 vertebral arteries, 1 internal carotid artery and 1 anterior cerebral artery. Initial symptoms were headache in 3 cases, headache with motor weakness in 2 cases, headache with dysarthria in 1 case, headache with dizziness in 1 case, and Wallenberg Syndrome in 1 case. The remaining 2 cases were diagnosed incidentally. Following initial conservative treatment, intravascular treatment was performed in 2 cases whose dissecting aneurysms increased in size after 7 to 7.5 months. Follow-up symptoms were no symptoms in 8 cases, dizziness in 1 case and hypertensive intracerebral hemorrhage in 1 case. Serial cerebral angiograms and/or MR images showed radiological changes in 7 cases, observed from 1 month to 2 years 4 months after initial onset. These findings suggest that initial conservative treatment resulted in relatively good clinical outcome in patients with non-hemorrhagic dissecting aneurysms, but surgical intervention should be performed when dissection increases. In addition, patients with non-hemorrhagic dissecting aneurysm should be carefully followed by cerebral and/or MR angiography until 1 or 2 years postonset.

Low molecular dextran is often used in post-operative management of subarachnoid hemorrhage (SAH) to induce hypervolemia and hemodilution; however, its associated complications are not well-known. We retrospectively analyzed prothrombin time (PT%), activated partial thromboplastin time (APTT%), and fibrinogen level as coagulation markers in patients with subarachnoid hemorrhage who developed delayed intracranial hemorrhagic complications after undergoing craniotomy for clipping to examine the effect of long-term use of low molecular dextran on bleeding tendencies. Fifty-two patients with SAH who underwent craniotomy were divided into 2 groups: 26 without post-operative use of low molecular dextran (Group 1) and 26 to whom low molecular dextran was administered for more than 5 consecutive days (Group 2). Group 2 was further divided into 2 subgroups: those who developed hemorrhagic complications (Group 2A) and those without complications (Group 2B). The frequency of complications in Group 2A was 19% (5/26; 3 with subdural hematoma and epidural hematoma, 1 with epidural hematoma, and 1 with intracerebral hematoma). Complications appeared 7.6 days on average after starting low molecular dextran. Compared with Group 1, PT% and APTT% as well as pre-and post-low molecular dextran administration fibrinogen levels significantly decreased in Group 2A. Low molecular dextran is known to decrease fibrinogen levels, and patients' clinical conditions and changes in fibrinogen levels should be closely monitored to detect bleeding tendencies when low molecular dextran must be used for long periods.

Although the perennial grass Dactylis glomerata L. has established dominant populations in Japan since its introduction in the 1870s, there have been marked reductions in its abundance in southern and northeastern regions. In order to examine the effects of climatic factors on distribution and differentiation of the naturalized populations of D. glomerata, abundance of 26 populations over a distance of 1500 km along a latitudinal gradient was recorded at each site, and life-history traits of each population were measured in a common garden. It was found that the reduction in abundance was related to the mean summer temperature in southern regions and to the lowest temperature before snow cover in northeastern regions. Recent climatic records in Japan show an increase in the mean summer temperature but no apparent changes in the lowest temperature before snow cover. These data suggest that, assuming the recent trend in climatic changes continues, the population abundance will decrease in southern regions and will change little in the northeastern regions. Germination speed, leaf width and reproductive allocations showed clinal variation over a geographical range, and the southern populations had more rapid germination, narrower leaves and lower reproductive allocation than did the northern populations. On the other hand, seed size and germination date showed margin-center differentiation. Marginal populations in both distributional borders had smaller seeds and lower germination rates than did the central populations.

The variation in nuclear DNA content and its association with phenotypic traits were examined in 15 cultivated populations of perennial ryegrass (Lolium perenne L.), including herbage and turf populations. Nuclear DNA contents of 15 populations were measured by a flow cytometric method using DAPI (4′-6-diamidino-2-phenylindole) as a fluorochrome. DNA contents were also measured using PI (propidium iodide) for six populations that showed large differences in DAPI values to confirm the difference. There were significant differences in nuclear DNA contents among the populations for both dyes. Of the total variation in nuclear DNA content measured with DAPI, 29% was ascribed to the inter-population variation, 46% was ascribed to the intra-population variation, 24% was ascribed to the random error variation. Herbage populations tended to have larger DNA content than did turf populations. 2C DNA content was positively correlated with cell size, seed size and single leaf size, although significant correlations were mainly due to a small number of populations with large and small DNA contents. These results suggest that intraspecific variation in nuclear DNA content plays important roles in determining phenotypic differences between cultivated populations of L. perenne.

In a diploid grass, perennial ryegrass (Lolium perenne L.), many autotetraploid cultivars have been released and widely used in many cool temperate countries. In this study, competitive ability and cold tolerance, which seem to be important factors in determining geographical distribution and persistency of this species, were compared between six diploid and five autotetraploid cultivars. The tetraploid cultivars had significantly higher competitive ability and lower cold tolerance than the diploid cultivars. Furthermore, there was no overlap in the two traits between them. These results suggest that chromosome doubling has a larger effect on competitive ability and cold tolerance than does the genetic difference between the populations within a single ploidy level.

A 7-year-old girl was admitted with an unusual anomaly of hemimegaloencephaly associated with periventricular heterotopia manifesting as intractable seizures and mental retardation. Magnetic resonance (MR) imaging showed left hemispheric hypertrophy and left ventricular dilatation. Proton density-weighted MR imaging revealed a periventricular lesion isointense with gray matter. MR imaging is an effective method for diagnosing hemimegaloencephaly and heterotopia.

One of the failures related to gas-insulated switchgear is caused by the poor contact between conductors. This causes breakdown between the contact and the wall of chamber, initiated by the small discharge due to the poor contact. In this paper, the modeled experimental apparatus for the contact portion of the gas-insulated switchgear assumed a rod-to-plane gap with small arc current. The influence of the arc current on the breakdown into the chamber was investigated experimentally, and the breakdown mechanism between the contacts and the wall was studied. It was clarified that the breakdown voltage between the contact and the wall decreased by increasing the current, and the small arc current in the contact portion played an important role in the breakdown between the contact and the wall. The reduction ratio of the breakdown voltage increased with increasing gap length of the small gap. The breakdown voltage was different depending on the duration of the small arc current.

A 53-year-old male with normal immunity presented with Aspergillus brain abscess manifesting as frontal headache. T2-weighted magnetic resonance imaging revealed a hypointense lesion in the left frontal lobe extending into the right frontal lobe. The hypointense appearance on T2-weighted images appears to be characteristic of aspergillosis. Bifrontal craniotomy exposed an elastic-hard mass in the base of the left frontal lobe extending into the right frontal lobe, and into the left ethmoid sinus. The mass contained a cavity with white fluid. The abscess was removed almost totally. The histological diagnosis was Aspergillus abscess. Antibiotic treatment with amphotericin B and fluconazole was given for 2 months postoperatively. No recurrence was identified during 15-month follow-up.

In Germany the project group of AEG, BBC and Siemens had succeeded in magnetically suspended test run with superconducting magnets for the first time in March 1976 on a circular test track in Erlangen. The test vehicle was propelled by an on-board linear induction motor. A clearance of 100mm between the track surface and the bottom of cryostats was achieved at 120km/h.Furthermore, a rotating drum test-rig for linear synchronous motor (LSM) is in preparation for conversion of the circular track to LSM system, because in future practical system the trains will be propelled by LSM.Outline of the plan for practical system is described also.