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A machine-learning classifier for radiation waveforms of negative return strokes (RSs) is built and tested based on the Random Forest classifier using a large dataset consisting of 14,898 negative RSs and 159,277 intracloud (IC) pulses with 3-D location information. Eleven simple parameters including three parameters related with pulse characteristics and eight parameters related with the relative strength of pulses are defined to build the classifier. Two parameters for the evaluation of the classifier performance are also defined, including the classification accuracy, which is the percentage of true RSs in all classified RSs, and the identification efficiency, which is the percentage of correctly classified RSs in all true RSs. The tradeoff between the accuracy and the efficiency is examined and simple methods to tune the tradeoff are developed. The classifier achieved the best overall performance with an accuracy of 98.84% and an efficiency of 98.81%. With the same technique, the classifier for positive RSs is also built and tested using a dataset consisting of 8,700 positive RSs. The classifier has an accuracy of 99.04% and an efficiency of 98.37%. We also demonstrate that our classifiers can be readily used in various lightning location systems. By examining misclassified waveforms, we show evidence that some RSs and IC discharges produce special radiation waveforms that are almost impossible to correctly classify without 3-D location information, resulting in a fundamental difficulty to achieve very high accuracy and efficiency in the classification of lightning radiation waveforms.

井上靖の詩「出発」は現在、学校図書『みんなと学ぶ・小学校国語六年上』（平成二十六年三月検定済）に巻頭教材として掲載されている。昭和二十二年一月一日『少国民新聞』に初めて発表され、かつて大阪書籍『小学国語6上』（平成十一年一月検定済）にも掲載されていた。この「出発」は、作者井上靖の少年少女へ向けた思いが十二分に表れており、国語教材として、特に一年間の学習の出発点で学ぶ巻頭教材として相応しい作品と言える。詩「出発」について、教材としての特色を分析した上で、その授業方法を考察したい。

This paper presents lightning mapping array (LMA) observations of corona discharges from a windmill and its lightning protection tower in winter thunderstorms in Japan. Corona discharges from the windmill, called windmill coronas, and those from the tower, called tower coronas, are distinctly different. Windmill coronas occur with periodic bursts, generally radiate larger power, and possibly develop to higher altitudes than tower coronas do. A strong negative electric field is necessary for the frequent production of tower coronas but is not apparently related with windmill coronas. These differences are due to the periodic rotation of the windmill and the moving blades which can escape space charges produced by corona discharges and sustain a large local electric field. The production period of windmill coronas is related with the rotation period of the windmill. Surprisingly, for one rotation of the windmill, only two out of the three blades produce detectable discharges and source powers of discharges from these two blades are different. The reason for this phenomenon is still unclear. For tower coronas, the source rate can get very high only when there is a strong negative electric field, and the source power can get very high only when the source rate is very low. The relationship between corona discharges and lightning flashes is investigated. There is no direct evidence that corona discharges can increase the chance of upward leader initiation, but nearby lightning flashes can increase the source rate of corona discharges right after the flashes. The peak of the source height distribution of corona discharges is about 100 m higher than the top of the windmill and the top of the tower. Possible reasons for this result are discussed.

本稿は「赤い実」を含めた「しろばんば」後編について、そこに隠されている一つのモチーフを明るみに出した指導法を提案し、国語教材として再生を試みようとするものである。

The main factors affecting the outcome of Trueperella pyogenes (T. pyogenes) mastitis were examined through a survey of diagnostic data and interviews relating to the occurrence of T. pyogenes mastitis in 83 quarters from 82 Holstein cows between August 2012 and April 2014. Ultimately, one cow was sold during the examination, and 82 quarters from 81 cows were used for analysis on prognosis. T. pyogenes mastitis occurred year round in both lactating and dry cows. The incidence of T. pyogenes mastitis did not significantly differ by month or show seasonality in either lactating or dry cows. Therefore, the occurrence of T. pyogenes mastitis also differed from that of summer mastitis. The 1-month survival rate of infected cows was 64.6% (53/82), and the recovery rate of quarters with T. pyogenes mastitis was 14.6% (12/82). Bivariate logistic regression analysis was performed with survival and culling of infected cows as objective variables and with recovery and non-recovery of quarters with T. pyogenes mastitis as objective variables. The severe cases were significantly culled (odds ratio, 16.30) compared to mild cases, and the status of quarters didn't recover (odds ratio, 6.50). The results suggest that mild to moderate symptom severity at the time of onset are the main factors affecting outcomes in cows and recovery of quarters infected with T. pyogenes mastitis. Further, high level of NAGase activity also suggested the potential use as an indicator of culling of cows with T. pyogenes mastitis.

Using a high-speed optical imaging system, we have observed the step formation bright pulse discharges occurring at the tip of dart-stepped leaders of rocket triggered lightning with a time resolution of 0.1 µs and a spatial resolution of about 1.4 m. Each of the step formation pulse discharges appeared to initiate at a location immediately below the bottom of its previous pulse discharge and to propagate in bidirectional (upward and downward) waves with a speed on the order of 107 m/s. The downward waves of the pulse discharges tended to slow down significantly after they propagated a distance of about 2 m. Based on the results observed in this study and those published in literatures, we propose a conceptual view of leader step formation.

We characterized 205 multiple-termination negative cloud-to-ground (CG) lightning flashes that were imaged by the Fast Antenna Lightning Mapping Array (FALMA) in Japan during the summer of 2017. The parameters we used included termination number, termination distance, fork height, return stroke (RS) number, the interval between the first RS of each termination, the shortest time difference between the strokes at different terminations, and the first RS intensities separated by termination occurrence orders. It was found that the multiple-termination flashes (MTFs) had a termination number ranging from 2 to 5, with the majority (148/205) at 2. The termination distance (with high probability) was between 2 and 4 km, with 10 out of 359 MTF termination distances being longer than 10 km. For most MTFs (146/205), their leader forks for different terminations occurred at a height between 4 and 6 km, indicating that the fork process mainly occurred inside the cloud. The RS number of the MTFs ranged from 2 to 18, with an arithmetic mean (AM) value of 5.8. The interval between the first RS of each termination in the MTFs ranged from 0.5 to 965.3 ms, with an AM value of 225.6 ms, while the shortest time difference between the strokes at different terminations had an AM value of 189.6 ms. The intensity of the first stroke in each termination tended to decrease with increasing termination occurrence orders.

Differentiation of stem cells to hepatocytes provides an unlimited supply of human hepatocytes and therefore has been vigorously studied. However, to date, the stem cell-derived hepatocytes were suggested to be of immature features. To obtain matured hepatocytes from stem cells, we tested the effect of culturing human-induced pluripotent stem (hiPS) cell-derived endoderm cells on collagen vitrigel membrane and compared with our previous reported nanofiber matrix. We cultured hiPS cell-derived endoderm cells on a collagen vitrigel membrane and examined the expression profiles, and tested the activity of metabolic enzymes. Gene expression profile analysis of hepatocytic differentiation markers revealed that upon culture on collagen vitrigel membrane, immature markers of AFP decreased, with a concomitant increase in the expression of mature hepatocyte transcription factors and mature hepatocyte markers such as ALB, ASGR1. Mature markers involved in liver functions, such as transporters, cytochrome P450 enzymes and phase II metabolic enzymes were also upregulated. We observed the upregulation of the liver markers for at least 2 weeks. Gene array profiling analysis revealed that hiPS cell-derived hepatocyte-like cells (hiPS-hep) resemble those of the primary hepatocytes. Functions of the CYP enzyme activities were tested in multi-institution and all revealed high CYP1A, CYP2C19, CYP2D6, CYP3A activity, which could be maintained for at least 2 weeks in culture. Taken together, the present approach identified that collagen vitrigel membrane provides a suitable environment for the generation of hepatocytes from hiPS cells that resemble many characteristics of primary human hepatocytes., Summary: We found that collagen vitrigel membrane used as scaffold potentiates differentiation of human induced pluripotent stem cells to differentiate into mature hepatocyte-like cells that exhibit mature functions of the hepatocytes.

we have examined the accuracy of locating return strokes with Fast Antenna Lightning Mapping Array (FALMA) after excluding CG flashes that may have multiple striking points with different locations. The mean and median errors are 27.4 m and 15.6 m, respectively. Several ground truths collected are basically supportive of such high accuracy of FALMA. It appears that FALMA can be used to assist in locating efficiently the damage mark caused by lightning discharges on various power transmission and distribution equipment. With the data recorded by FALMA during the summer of 2017, which include more 3300 CG flashes, we have performed a simulation on forecasting CG flashes with FALMA at various prediction radiuses and forecast times. With a prediction radius of 10 km and a forecast time of 30 minutes, we found that 99.5% CG flashes can be forecasted. For 98% CG flashes, the prediction lead time is more than 5 minutes. Both the failure prediction and the short lead time deteriorate with the decreasing prediction radius. For different types of applications, the prediction time can be optimized to be as short as several minutes to about 30 minutes.

There are many unsolved molding phenomena in the hot-runner mold system, which are caused by complicated flow channels installed with actuated valve-pins inside the high temperature manifold. In the injection molding of large or long-sized products, melts are made to flow continuously by sequentially switching gate-opening one by one from upstream to the area contacting the flow front. Valve gates are appropriately controlled to open/close by the so called “cascade control system”, to prevent weld-lines, decrease flow pressure loss, etc. However compared to the single gate system, more complicated flow behaviors are expected to occur when the valve gate near the flow front is opened at the times of open gates. We attempted to visualize the melt behaviors inside hot-runner mold with a cascade control of two sets of valve gates (upstream VG1 and downstream VG2). Through this visualization experiment, the following results were confirmed. (1) In the case of the direct gate system, where multi-gates are located inside the mold cavity, the flow front velocity was observed to rapidly rise up to 5 or 6 times in a moment after a small amount of back flow, due to low pressure loss at the flow front area just after switching the gate open from VG1 to VG2. (2) In the case of sub-runner systems, where multi-gates are located in the tub area outside the cavity, the later VG1 is switched to VG2, the higher the velocity peak of the melts flowing into the cavity from VG2. All these drastic velocity changes may influence upon surface transcription conditions, leading to surface defects on molded samples.

In this study, we synthesized hollandite-type manganese oxide octahedral molecular sieves (OMS) with different potassium content (K x Mn 8 O 16 ; K-OMS-2). Owing to crystal growth, the specific surface area of K-OMS-2 decreased with an increase in the K concentration for x > 1.5. The K-OMS-2 samples with x

In this study, we compared the histologic and morphometric properties of both internal thoracic arteries and the right gastroepiploic artery (GEA) in patients undergoing coronary artery bypass grafting (CABG).We microscopically examined transverse sections of segments of both internal thoracic arteries and the right GEA obtained from 83 consecutive patients who underwent CABG.There were no significant differences between the internal thoracic arteries. Significant differences were found between the left and right internal thoracic arteries and GEA in the intimal width (21.8, 21.5, and 71.7 μm, respectively; P .01), intima-to-media ratio (0.286, 0.256, and 0.749, respectively; P .01), and media width (148.5, 157.5, and 164.8 μm, respectively; P = .43). No atherosclerotic lesions, medial calcification, or intimal thickening were seen in the internal thoracic arteries; however, atherosclerotic lesions were seen in the GEA. The intima of the GEA was thicker than that of the internal thoracic arteries. Intimal thickening of the GEA, but not the internal thoracic arteries, was positively correlated with risk of arteriosclerosis. In patients with diabetes mellitus, dietary/drug therapy and insulin therapy were associated with GEA intimal thickness (P = .02 and .01, respectively).The internal thoracic arteries have equivalent histologic and morphometric properties that differ from those of the GEA only in intimal width. The former had no intimal thickening, and is thus preferable to the GEA for CABG.

Attached are frames of ahigh speed video that supportthemanuscript entitled “Formation Features of Steps and Branches of an Upward Negative Leader”. The data can be used freely for scientific purposes with appropriate citation.