Northern Kanto Area Research Articles

Clinical Impact of Bacteremia Due to <i>Staphylococcus saprophyticus</i>

Objective: This was a retrospective study to evaluate the clinical impact of bacteremia due to Staphylococcus saprophyticus and identify which factors influence it. Methods: We reviewed all patients with bacteremia due to S. saprophyticus over the last 12 years. This study was performed at Jichi Medical University Hospital in Japan, a key hospital in the northern Kanto area including Tochigi, Gunma, Ibagagi, and northern Saitama prefectures. We retrospectively reviewed the blood culture results and medical records of all patients with a history of visits or hospitalizations between April 2008 and September 2020. Results: During the study period, 4 blood culture specimens were considered to have S. saprophyticus bacteremia. Two of these were from subjects > 60 years old who had severe infection. A third case, 27 years old, was thought to have a catheter-related bloodstream infection; however, the only symptom was fever, which was not serious. The fourth case, a previously unreported pediatric patient, had non-severe fever. The mean time for a diagnosis of bacteremia by blood culture testing was 42 hours, whereas contamination appeared in cultures after another 50 hours. Conclusion: The pathogenicity of S. saprophyticus might be lower in the blood than in the urine due to its physiological function and activity. In older adults with underlying diseases, the severity of bacteremia was more pronounced, whereas in a young adult and a child, the disease was relatively mild. Age and underlying disease might be useful factors to consider when diagnosing bacteremia due to S. saprophyticus.

Efficacy of soil moisture conditions on the formation of ectomycorrhizal colonization and 137Cs absorption

Oak represents one of the most adaptable and resilient trees on earth and is widely distributed in multiple environments ranging from wet to dry. Japanese oak forests of Fukushima and the northern Kanto area were contaminated with radiocesium (137Cs) by Fukusima Dai-ichi nuclear Power Plant accident. 137Cs trapped at the surface soil has a deleterious effect on forest ecosystem and poses further threat to humans when it enters the food chain. The uptake of 137Cs and other essential nutrients such as nitrogen (N), phosphorus (P) and potassium (K) by plants with the aid of ectomycorrhizal fungi is affected by soil water content. The objective of this study was to evaluate the colonization rate of ectomycorrhiza (CRE) and its impact on nutrients and 137Cs uptake pattern by oak (Quercus serrata Thunb.) seedlings at different soil water content levels under greenhouse condition. The result shows that the growth of Q. serrata seedlings increased with increasing soil water content. In addition, the highest CRE was observed in the low water content (LW) and was significantly different from the high water content treatment (HW). The LW treatment showed the highest N and P concentration in leaves and roots although no statistical differences were observed compared to the other treatments. Treatments with 137Cs-amended litter showed increased 137Cs concentration in the leaves of plants and its leaf per root ratio increased with decreasing soil water content. The results of the present study also suggest enhanced 137Cs absorption and translocation into Q. serrata seedlings is with the aid of ectomycorrhizal fungus except for the seedlings in HW.

First detection of summer blue jets and starters over Northern Kanto area of Japan: Lightning activity

Numerous summer blue jets and blue starters were observed for the first time over the Northern Kanto area of Japan on 15 August 2008. Sixty jets and starters were observed, and emissions continued intermittently for more than 20 min. Very high frequency (VHF) and low‐frequency (LF) lightning activity and extremely low frequency (ELF) transients associated with these phenomena were analyzed during the 5 s before and after their appearance. We found the following unique characteristics of lightning accompanied by jets/starters: (1) the interval of emissions was different for jets and starters; (2) the jets were strongly connected with negative cloud‐to‐ground lightning discharges (–CGs), but starters might have been more affected by intra‐cloud discharges (ICs); (3) the number of –CGs and ICs quickly increased just before a jet and showed a significant reduction after the jet; (4) the –CG activities began to decay 0.5 s before a starter, although IC activities were very active ±1 s of a starter; (5) the charge moment change within ±1 s of the jets and starters, as calculated from ELF transients associated with CGs, were ∼−200 and ∼−100 C⋅km, respectively; (6) the lightning discharges with jets/starters are clustered in a limited area of overshooting storm top. These results indicate that the same thunderstorm produced both a jet and a starter. This led us to hypothesize that the emittance of either a jet or starter is dependent on the amount of accumulated positive charge and the electrical activities of the parent storm.

Source apportionment of ambient fine particle using a receptor model combined with radiocarbon content in Northern Kanto area

Source apportionment of ambient fine particle using a receptor model combined with radiocarbon content in Northern Kanto area

風力エネルギーを利用した有孔管方式によるサンドバイパスシステムの試設計

This paper introduces a new concept of coastal management system in order to protect beaches against erosion, by transporting sand materials from the near-by deposition area to the eroded beach using wind power energy without CO2 emission. A new Sand Bypass system using pipes with holes was developed and the field tests were conducted at the Northern Kanto area beach faced to the Pacific Ocean. Results of the tests showed that 100kW electric power supply was necessary in the system, and 300kW-typed offshore wind generator was recommended with the system. Estimated CO2 emission reduction rate was also discussed.

Phylogenetic relationships and phylogeography of Hynobius tokyoensis (Amphibia: Caudata) using complete sequences of cytochrome b and control region genes of mitochondrial DNA

Using complete sequences of cytochrome b (cyt b) and control region (CR; D-loop) genes of mitochondrial DNA, we investigated the phylogenetic relationships and phylogeography among populations of the salamander Hynobius tokyoensis in northern Japan. Inclusion of populations from Aichi, Chubu region within Hynobius nebulosus by previous results was confirmed because they formed a clade with H. nebulosus. Monophyly of H. tokyoensis was supported in all trees analyzed, and two clades consistently emerged: clade A from northeastern Kanto (Ibaraki) to southern Tohoku (Fukushima), and clade B from the remaining area south of northern Kanto (Tochigi). These two clades are estimated to have an old history of divergence during the late Pliocene, when the present-day Kanto Plain was under the sea. Within clade B, three haplotypes groups (I–III) are hypothesized to have diverged more recently, i.e., between the early and mid-Pleistocene, probably in relation to glacial events. The ancestral groups I and II were separated at the present-day western Kanto and Boso Peninsula areas, respectively, and subsequently, group II invaded northward to the present-day northern Kanto area and gave rise to group III. Populations of the Miura Peninsula are thought to have multiple origins, one directly from Boso and another from a more recent southward invasion from the northern Kanto area. Cytochrome b appears to have evolved more quickly than CR genes in H. tokyoensis, and thus will be more useful for phylogenetic analyses and formulating conservation measures.

Relationship Betwenn Feed Composition During Dry Period and Reproductive Performance of Dairy Cows in the Northern Kanto Area of Japan

Relationship Betwenn Feed Composition During Dry Period and Reproductive Performance of Dairy Cows in the Northern Kanto Area of Japan

Historical biogeography and interspecific mtDNA introgression in Euhadra peliomphala (the Japanese land snail).

We assess variation in mitochondrial DNA (mtDNA) using partial sequences (560 bp) of the COI gene among populations of Japanese land snails, Euhadra peliomphala. Phylogeographical analysis reveals five primary clades that correspond basically to five discrete areas: the Boso Peninsula (B), the Kanto area (K), around Lake Ashinoko (A), the Northern Izu Peninsula (N), and the Southern Izu Peninsula (S). Although there are no current geographical barriers separating these five subpopulations, the borders between each area correspond to palaeogeographical events during the Pleistocene, such as volcanic activities and the disappearance of the landbridge between the Southern Boso area and the mainland of Japan. In addition, our analysis of isolation-by-distance and the distribution of pairwise sequence differences indicate that haplotypes of the B and K lineages have recently increased their population size exponentially. We have also discovered interspecific mtDNA introgression between E. peliomphala and the parapatric species E. brandtii at the contact zone in the Northern Kanto area. Unexpectedly, the E. brandtii-type mtDNA was also found in the populations of E. peliomphala in the Southern Boso area. Because recent contact between both species is unlikely, the introgressed mtDNA of E. brandtii could be a remnant of past hybridization, when E. peliomphala colonized this area via the landbridge that existed in the early Pleistocene.

Iodine Determination in Natural and Tap Water Using Inductively Coupled Plasma Mass Spectrometry

The measurement of iodine in natural-water samples by inductively coupled plasma mass spectrometry (ICP-MS) is described. The limit of detection is 10 pg/mL The element is easily determined by this method without separation or preconcentration. Because iodine is highly volatile, the obtained signal is somewhat unstable. Iodine vaporization, however, can be restrained by the addition of an organic alkali (for example tetramethyl ammonium hydroxide), making it possible to obtain a stable signal. Analytical results using the conventional calibration-curve method and the standard addition method agreed well We determined the iodine concentration of 42 natural-water samples in the northern Kanto area. The concentrations of iodine ranged from 0.65 to 35.9 ng/ml.

39. Volcanic Front and Deep Seismic Zone in Northern Kanto Area(Abstracts of Papers Presented at the Fall Meeting of the Society)

39. Volcanic Front and Deep Seismic Zone in Northern Kanto Area(Abstracts of Papers Presented at the Fall Meeting of the Society)

Distribution of Rrecipitation during the Short Dry Period of Mid-Summer in Fukushima Prefecture and Northern Kanto Area

It is said that Japan has a short dry period in mid-summer. However even in such a period, the local rainfall is frequent in some regions. The author clarifies the distribution of such a local rainfall during the short dry period, using data for precipitation in Fukushima Prefecture and Northern Kanto area (Fig. 1).The results are summarized as follows;1) The local rainfall in mid-summer is often observed along the north borders of Tochigi Prefecture. This area does not always coincide with the region abundant in total summer precipitation (Fig. 3).2) As a whole, the local rainfall in mid-summer occurs during 1600-1800 JST, and it tends to stop within two hours (Table 1), but each station has a different characteristic in hourly occurrence (Fig. 4). In the northwestern Tochigi Prefecture, the local rainfall in mid-summer inclines to occur in the earliest time (Fig. 5 and Fig. 7).3) The ratio (%) of amount of precipitation in the dry period of mid-summer to that of total summer precipitation is highest, about 20%, in Yamizo Mountains, Tadami area, and around Kiryu (Fig. 9). The ratios fluctuate considerably year-to-year, and in some case, they exceed 50%.

Biosystematic studies of theClosterium peracerosum-strigosum-littorale complex

Nine representative pairs of heterothallic (=self-sterile, cross-fertile) strains of theClosterium peracerosum-strigosum-littorale complex from the northern Kanto area in Japan have been studied under the defined standard culture conditions. Since a wall thickening at cell apices was observed in vegetative cells of all the strains, these strains turned out to belong to the morphological group II (Ichimura and Watanabe, 1976). The result of statistical analyses of their cell size variations corresponded well with the result of intercrossing experiments between them. It was shown that these strains are virtually composed of three biologically different groups which are morphologically distinct and reproductively isolated completely or at least partially from each other. For convenience, these three groups have been designated as II-A, II-B, and II-C in the order of from smaller to larger cell size. In intra-group crossings, a large number of zygospores were formed, and they germinated well to yield healthy populations of their progenies in all the three groups. In inter-group crossings, no sign of sexual reproduction was observed between Group II-A and Group II-C or Group II-B and Group II-C, and a marked decrease of zygospore formation was observed between Group II-A and Group II-B, especially between Group II-A minus and Group II-B plus. It was concluded that the distinctions between the three groups are biologically sound and that each represents an evolutionary unit.

P waves to seismological stations in Japan from the underground explosion of November 6, 1971, at Amchitka Island.

The travel times of P waves to Japan from the underground nuclear explosion of November 6, 1971, at Amchitka Island, the Aleutian Islands, deviate systematically with region in comparison with the travel times by CARDER et al. (1966). Arrival times at stations on the Pacific coastal region from Hokkaido to the northern Kanto area, the northern part of west Japan, and at islands near Japan (Izu Is., Ryukyu Is. and islands in the Sea of Japan) are somewhat earlier than the Carder et al. times. On the other hand, at stations in the southern Kanto, southern Chubu, central and southern Kinki, Shikoku and Kyushu areas, the arrival times are later as a whole. The body wave magnitude MB, estimated from the data in the Japan Meteorological Agency network is larger by about 0.7 than that reported by USNOAA. It is noticed that the discrepancy between them is probably caused by the difference of the frequency responses of seismographs used for the estimation.

THE REGIONAL DIVISION IN JAPAN FROM THE STANDPOINT OF THE DEVEOPMENT OF TELEPHONE COMMUNICATION

A human being has been endeavoring to enlarge the living space and to shorten the time of correspondence. As a means to achieve this purpose we have communication, which always arises at a certain place, alternates and gradually shortens the time of correpondence to zero. In other words, we are accelerating the alternation between areas of human groups and changing the form and function of the construction of each area. And we can see differences both in the alternating and arising of communication according to the areas. Now in this study, we are going to divide Japan into areas, 278 planet cities which are municipalized, as model ones, according to the arising of telephone communication. Concerning the way of study we count out quantitative factors such as population, amount of enterprising, number of workers in the second class industry as well as those of the third class and the proceeds of shops. In order to vanish the influence we made a function as follows: X0=-1.028+0.091X1+0.0128X2-0.064X3-0.049X4+0.145X5+ε' And we also tried the same thing for the qualitative factors such as dwelling planet cities, hotspring cities and important port cities, using the statistical way of measuring. Finally we have divided Japan into 13 areas, from which we have tried to reduce influence caused as mentioned above and have found that the following 13 areas still have their own powers. 1. Hokkaido area ……………………………0.003 2. Tohoku area ……………………………0.019 3. Northern Kanto area …………………-0.072 4. Eastern Tokai area ……………………0.042 5. Mid11e land of Japan ……………………0.054 6. Middle back side of Japan ……………0.036 7. Chukyo area ………………………………0.049 8. Kinki area ………………………………0.105 9. Sanin area ………………………………-0.067 10. Sanyo area ………………………………0.015 11. Shikoku area ……………………………-0.066 12. Northern Kyushu area ………………0.022 13. Southern Kyusyu area ………………-0.183 It shows that Kinki area becomes the center, Tokai and Hokuriku higher than average in the power of arising of communication; the power is gradually reducing to below average, as if goes on toward the southern part of Japan, such as Sanyo, Shikoku and Kyushu. In other words the eastern part of Japan is high and the western and southern part low. It means that the middle of Japan is regarded as an advanced area, and the south-western part the last one, and the north-eastern part the middle area regarding of telephone-communication.