Alloy development for turbine blade materials with higher temperature capabilities is crucial in order to improve the thermal efficiency in jet engines and gas turbine systems. The Ni-base single crystal (SC) superalloy, TMS-238, developed by NIMS has a good microstructure stability and 1120℃ temperature capability (1000 hours creep rupture life under stress of 137 MPa). In the previous studies, we investigated the influence of alloying elements on microstructure and creep strength of TMS-238 to improve the temperature capability of this alloy. The rupture life of TMS-238+ReRu alloy which had increased Re and Ru concentrations based on TMS-238 was three times longer than TMS-238 under the condition of 1150℃-137 MPa. In the case of 1000℃ and 900℃ and at higher stresses conditions, however, rupture lives of TMS-238+ReRu alloy were shorter than TMS-238 due to fine TCP phase precipitation during creep test. In this study, we examined effect of substituting Ru with Ir in TMS-238+ReRu to improve the stability of γ-γ′ two-phases microstructure and the creep strengths. As a result, the rupture life of TMS-238+ReIr was longer than TMS-238+ReRu under the condition of 900℃-392 MPa. This is due to suppression of fine TCP phase precipitation and the solution strengthening of Ir. In the case of 1150℃-137 MPa, the rupture life of TMS-238+ReIr was shorter than TMS-238+ReRu but longer than TMS-238.

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A global evaluation is made of the candidate geomagnetic field models for the DGRF 1990 (main field) and IGRF 1995 (main field and secular variation). An evaluation of these models is also made with respect to the previous ( ) IGRF. The models are compared with each other and, where possible, with recent data from observatories, magnetic surveys including repeat stations, Project MAGNET and marine surveys. It is concluded that, although there are some large differences between the candidate models, there is not enough evidence to recommend one model in favour of another. The IGRF, however, fits the Project MAGNET data better than any of the candidate models. It is suggested that each model be given equal weight in the production of DGRF 1990 and IGRF 1995 main-field models.

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As the

mobile communication system is expected to use the terahertz wave band, it is essential to clarify the human body blocking and scattering characteristics as many small cells for indoor and outdoor use will be needed. In addition, since it is important to use high-gain antennas with orthogonal polarization to realize efficient MIMO transmission, it is necessary to clarify the polarization characteristics of human body blocking and scattering. Experiments conducted to investigate human body scattering in the terahertz wave band show that the scattering characteristics are polarization dependent.

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The pyrrhocorid bug, Pyrrhocoris sibiricus, which is a ground-dwelling seedfeeder, shows a wing polymorphism producing brachyptery and macroptery. A selection experiment for different wing forms was carried out at 30°C under 12L-12D to investigate whether or not the wing form of this species is a heritable trait. In the macropterous selected line, the incidence of macroptery reached a plateau at around 70% in females and at 80% in males after the 4th generation. On the contrary, in the brachypterous selected line, almost no macropters were produced after the in either sex. These responses to selection for the two wing forms clearly showed that wing form is a heritable trait in P. sibiricus. Realized heritabilities for the two wing forms were estimated by the degree of response to wing form selection in both sexes. The realized heritability for macroptery was estimated to be 0.48 for females and 0.78 for males. On the other hand, the realized heritability for brachyptery was estimated to be 1.57 for females and 1.54 for males.

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　新型汚泥保持スポンジ担体を用いたDown-flow Hanging Sponge (DHS-G6)法を，都市下水を処理するUASBの後段処理に適用し，連続運転試験を行なった．本システムは，HRT8.8時間(UASB6.6h，DHS2h)，平均温度25°Cの条件下で，8mg-BOD/Lおよび4mg-TKN/Lの良好な処理水質を得た．新型スポンジ担体の保持汚泥濃度は18.1g-VSS/Lと，前世代型スポンジ担体よりも低かったが，一方でDHS-G6は，理論HRT120分に対する実測HRTが67分となり，短絡流の抑制については，DHS-G6と同様のランダム充填方式である前世代型DHS(G3)よりも改善されていた．DHS-G6の酸素供給は自然通気のみで，反応器内の酸素濃度は外気と同程度となり，処理水のDOは8.1mg/Lを得た．DHS-G6では，優れたDO供給に加え，保持汚泥が高い硝化活性(最大60mg-N/g-VSS·day)を有していたことで，卓越したTKN除去性能を発揮したと考えられた．

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We present the methods used to derive mathematical models of global secular variation of the main geomagnetic field for the period 1985 to 2000. These secular-variation models are used in the construction of the candidate US/UK models for the Definitive Geomagnetic Reference Field at 1990, the International Geomagnetic Reference Field for 1995 to 2000, and the World Magnetic Model for 1995 to 2000 (see paper II, Quinn et al., 1997). The main sources of data for the secular-variation models are geomagnetic observatories and repeat stations. Over the areas devoid of these data secular-variation information is extracted from aeromagnetic and satellite data. We describe how secular variation is predicted up to the year 2000 at the observatories and repeat stations, how the aeromagnetic and satellite data are used, and how all the data are combined to produce the required models.

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Thanks to the development of the

mobile network that makes it possible for us to move towards an intelligent ubiquitous information society, among which some novel technologies represented by cell-free network has also attracted widespread academic attention. Cell-free network has brought distinguished gains to the network capacity with its strong ability against inter-cell interference. Unfortunately, further improvement demands more base stations (BSs) to be settled, which incurs steep cost increase. To address this issue, reconfigurable intelligent surface (RIS) with low cost and power consumption is introduced in this paper to replace some of the trivial BSs in the system, then, a RIS-aided cell-free network paradigm is formulated. Our objective is to solve the weighted sum-rate (WSR) maximization problem by jointly optimizing the beamforming design at BSs and the phase shift of RISs. Due to the non-convexity of the formulated problem, this paper investigates a joint optimizing scheme based on block coordinate descent (BCD) method. Subsequently, on account of the majority of the precious work reposed perfect channel state information (CSI) setup for the ultimate performance, this paper also extends the proposed algorithm to the case wherein CSI is imperfect by utilizing successive convex approximation (SCA). Finally, simulation results demonstrate that the proposed scheme shows great performance and robustness in perfect CSI scenario as well as the imperfect ones.

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タバコモザイクウイルス(TMV)に罹病したタバコ(ブライトエロー)の茎から起こした培養組織をMurashige and Skoogの培地を用い,緑色で固い表面組織,表面と内部の中間部分および透明で軟かい内部をそれぞれ継代培養することにより下記の3種類のカルスを得た。カルスA,密に相接した小細胞からなる緑色のカルス。カルスB,緑色で固い表面組織と透明で軟かい内部の組織からなるカルス。カルスC,ルーズな大細胞からなる透明で軟かいカルス。
カルス中のTMV濃度は透明で軟かい内部を継代培養すると低下したが,緑色で固い表面の組織を継代したときには高濃度に保たれた。カルス中のTMVの分布と組織の状態との関係を蛍光抗体法を用いて観察した結果,カルス中のTMV抗原は偏在しており,導管様細胞のまわりの密に相接した小細胞の集団にしばしば分布していたが,ルーズな大細胞からなる組織にはあまり認められなかった。透明で軟かいカルス組織を継代することによってTMV濃度が低下する原因はウイルス感染からまぬがれた健全な細胞が急激に増殖するためであろうと考えられる。

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Background The diagnostic sensitivity of current bronchoscopy for peripheral lung cancer is inadequate because the bronchoscope insertion range is limited and confirmation of the position of the biopsy apparatus at the lesion under X-ray fluoroscopy is inaccurate. The combination of ultrathin bronchoscopy and computed tomography (CT) is effective for solving these problems.
Objective This study was a retrospective study analyzing prospectively collected data to identify factors contributing to the diagnosis and the appropriate biopsy method in CT-guided ultrathin bronchoscopy for peripheral lung cancer.
Methods The subjects comprised 86 patients (88 lesions) who underwent CT-guided ultrathin bronchoscopy and were finally diagnosed with peripheral lung cancer. We evaluated the diagnostic yield according to specific factors and also according to the sample collection method.
Results Sixty-nine lesions were diagnosed as lung cancer, and the diagnostic yield was 78.4% (80.3% in lesions ≤2 cm in diameter). Multivariate analysis showed that the factors contributing to the diagnosis were the observation range by ultrathin bronchoscopy and the presence/absence of the involved bronchus or pulmonary artery. Pathological evaluation facilitated histological diagnoses in 53 (65.4%) of 81 lesions. In 16 lesions, only the cytological diagnosis was positive.
Conclusion CT-guided ultrathin bronchoscopy may be particularly useful for lesions for which the involved bronchus or pulmonary artery can be confirmed, and observation of bronchi of the or more is possible. Since the specimen preparation rate is low, the combination of histopathological diagnosis with cytological diagnosis particularly that of the discharge attached to the forceps, is optimal.

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【目的】Wall area percentage（WA%）の測定にAdvanced intelligent Clear-IQ Engine （AiCE） lungで再構成した高精細画像を使用して，第7世代気管支までWA%を測定し，遠位気管支で測定したWA%ほど呼吸機能（FEV₁%）との相関がより強くなることを示す．更に，空間分解能が高い画像から測定したWA%ほどFEV₁%との相関が強くなることを実証する．【方法】AiCE bobyおよびAiCE lungで再構成した高精細画像の物理評価および臨床評価を行った．物理評価では，modulation transfer function（MTF）およびnoise power spectrum（NPS）を測定した．臨床評価は，右肺のB1とB10の第7世代気管支までのWA%を測定し，FEV₁%との相関係数を求めた．【結果】MTFはAiCE lungのほうがAiCE bodyよりも高かった．NPSは低周波域においてAiCE bodyと比べてAiCE lungのほうが低下していた．臨床評価は，AiCE body，AiCE lungともB1とB10の第7世代までの気管支のWA%を測定でき，遠位気管支で測定されたWA%ほどFEV₁%との相関が強くなった．WA%とFEV₁%との相関値は，AiCE lungのほうがAiCE bodyよりわずかに強かった．【結語】AiCE lungで再構成した高精細画像を使用して，第7世代気管支でWA%を測定することにより，WA%とFEV₁%との相関が強くなることを示した．また，測定用画像の空間分解能が高いほどWA%とFEV₁%との相関が強くなることを実証した．

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Background: The effects of bronchial thermoplasty (BT) on smooth muscle (SM) and nerves in small airways are unclear.

Methods: We recruited 15 patients with severe refractory asthma, who received BT treatment. Endobronchial optical-coherence tomography (EB-OCT) was performed at baseline, 3 weeks' follow-up and 2 years' follow-up to evaluate the effect of BT on airway structure. In addition, we divided 12 healthy beagles into a sham group and a BT group, the latter receiving BT on large airways (inner diameter >3 mm) of the lower lobe. The dogs' lung lobes were resected to evaluate histological and neuronal changes of the treated large airways and untreated small airways 12 weeks after BT.

Results: Patients receiving BT treatment had significant improvement in Asthma Control Questionnaire (ACQ) scores and significant reduction in asthma exacerbations. EB-OCT results demonstrated a notable increase in inner-airway area (Ai) and decrease in airway wall area percentage (Aw%) in both large (3rd-to

-) and small (7th-to 9th-generation) airways. Furthermore, the animal study showed a significant reduction in the amount of SM in BT-treated large airways but not in untreated small airways. Protein gene product 9.5 (PGP9.5)–positive nerves and muscarinic receptor 3 (M3 receptor) expression in large and small airways were both markedly decreased throughout the airway wall 12 weeks after BT treatment.

Conclusions: BT significantly reduced nerves, but not SM, in small airways, which might shed light on the mechanism of lung denervation by BT.

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受精卵移植(MOET)によって造成される肉用牛小集団において,優性効果が遺伝的改良量に及ぼす影響を遺伝子効果を考慮した選抜交配シミュレーションを用いて検討した.集団は各世代60頭からなるとし,世代は重複するとした.対象形質は相加的および優性効果を持つ64遺伝子座によって支配され,また両性で観察されるとした.遺伝子頻度の影響を確かめるために形質に正の効果を持つ遺伝子の頻度を0.2,0.5および0.8とし,広義の遺伝率を0.6とした.また各胚提供雌は1世代につき4頭の後代を生産するとした.雄5頭,雌15頭をアニマルモデルBLUP法による育種価予測値によって選抜し,この選抜交配を6世代にわたって行なった.育種価は相加的効果のみを考慮するモデルと優性効果をも考慮するモデルによって予想した.その結果,MOETのように個体間により多くの優性血縁関係が生じる集団において育種価を予測する場合,優性効果をも考慮できるモデルによって,正確度が高く,偏りの小さな予想値が得られる傾向が認められ,このことは中程度の遺伝子頻度,すなわち新たに交雑などにより造成された集団で育種価予測値による選抜を開始するような場合には特に顕著であった.また,このモデルによる育種価予測値を用いた選抜の結果,わずかながら高い遺伝的改良量が得られることが明らかとなり,MOETによる集団での遺伝的評価において,計算時間や費用の制約がなければ優性効果を考慮する必要のあることが示唆された.

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Transplantation experiments were made on spontaneous hepatomas. Among eight hepatomas, two transplantable hepatomas were established, one of which, FSH-2417, reached 15th generations after four years. Their histological appearance was that of well-differentiated hepatocellular tumor and was well-preserved throughout the serial transplantation. The activity of glucose-6-phosphatase and ATPase, and the contents of cytochrome b₅ and P-450, which are specific components for the liver, were well maintained in the hepatomas.

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30日ごとに70代継代したタバコカルスの内,緑色で密な組織からなり,タバコモザイクウイルス(TMV)を高濃度に含むカルスを分化培地に移すと多数の芽が分化したが,TMVを含む緑色のカルスからなるべく透明な部分を継代することによって得た無ウイルスの透明なカルスでは分化が認められなかった。TMVを除去したカルスから芽を分化させる条件を検討した結果,長期(50日)の継続代期間,高濃度(2mg/l)のカイネチンを含む培地の使用,あるいは強い光条件下(3,000-12,000lux)での培養が好適であることが明らかになった。これらの条件下で生じたウイルス除去カルスの緑色がかった固い部分を毎回継代することによって得た緑色で密な組織は分化能を再び獲得した。
6年間継代培養したカルスから得た小植物はすべて異数体であったが,TMVに罹病した茎から新たに起こし,ウイルスを除去したカルスから得た無ウイルスの植物は元の植物の染色体数(2n=48)を有していた。

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Breeding of alfalfa (Medicago sativa L.) for resistance to sclerotinia crown and stem rot (SCR, causal agent: Sclerotinia trifoliorum Eriks.), which is a serious disease in Japan, was initiated in 1983. Increase of resistance to this disease has been examined following repeated selection of surviving plants from artificially inoculated field plots to the 9th generation. The strains selected for SCR resistance showed a higher resistance than Natsuwakaba and Tachiwakaba which were used as breeding materials and control cultivars. The effectiveness of selection based on the survival rate of the progenies increased gradually as generations in which the recurrent selection was performed advanced. Realized heritability was low in the 1st and 2nd generations in which selection was performed but was high in the 3rd to 9th generations. It is considered that the selection effect on the SCR resistance was enhanced in the subsequent generations. The results of these studies may indicate that recurrent selection is effective for the accumulation of resistance genes with minor polygenic effect, especially in the case of breeding work for the improvement of characters, which had been considered almost impossible by short-term selection trials.

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Channel state information (CSI) acquisition at the transmitter side is a major challenge in massive MIMO systems for enabling high-efficiency transmissions. To address this issue, various CSI feedback schemes have been proposed, including limited feedback schemes with codebook-based vector quantization and explicit channel matrix feedback. Owing to the limitations of feedback channel capacity, a common issue in these schemes is the efficient representation of the CSI with a limited number of bits at the receiver side, and its accurate reconstruction based on the feedback bits from the receiver at the transmitter side. Recently, inspired by successful applications in many fields, deep learning (DL) technologies for CSI acquisition have received considerable research interest from both academia and industry. Considering the practical feedback mechanism of 5th generation (5G) New radio (NR) networks, we propose two implementation schemes for artificial intelligence for CSI (AI4CSI), the DL-based receiver and end-to-end design, respectively. The proposed AI4CSI schemes were evaluated in 5G NR networks in terms of spectrum efficiency (SE), feedback overhead, and computational complexity, and compared with legacy schemes. To demonstrate whether these schemes can be used in real-life scenarios, both the modeled-based channel data and practically measured channels were used in our investigations. When DL-based CSI acquisition is applied to the receiver only, which has little air interface impact, it provides approximately 25% SE gain at a moderate feedback overhead level. It is feasible to deploy it in current 5G networks during 5G evolutions. For the end-to-end DL-based CSI enhancements, the evaluations also demonstrated their additional performance gain on SE, which is 6%-26% compared with DL-based receivers and 33%-58% compared with legacy CSI schemes. Considering its large impact on air-interface design, it will be a candidate technology for

(6G) networks, in which an air interface designed by artificial intelligence can be used.

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