Purpose: To compare the quality of dynamic imaging between stack-of-stars acquisition without breath-holding (

-Star) and the breath-holding method (Cartesian LAVA and ).

Methods: This retrospective study was conducted between October 2019 and February 2020. Two radiologists performed visual assessments of respiratory motion or pulsation artifacts, streak artifacts, liver edge sharpness, and overall image quality using a 5-point scale for two datasets: Dataset 1 (n = 107), patients with Cartesian LAVA and

-Star; Dataset 2 (n = 41), patients with and -Star at different time points. Diagnosable image quality was defined as ≥ 3 points in overall image quality. Whether the scan timing of the arterial phase (AP) was appropriate was evaluated, and results between the pulse sequences were compared. In cases of inappropriate scan timing in the -Star group, retrospective reconstruction with a high frame rate (80 phases, 3 s/phase) was added.

Results: The overall image quality of Cartesian LAVA was better than that of

-Star in AP. However, noninferiority was shown in the ratio of diagnosable images between Cartesian LAVA and -Star in AP. There was no significant difference in the ratio of appropriate scan timing between -Star and Cartesian LAVA; however, the ratio of appropriate scan timing in -Star with high frame rate reconstruction was significantly higher than that in Cartesian LAVA in both readers. Overall image quality scores between and -Star were not significantly different in AP. There was no significant difference in the ratio of appropriate scan timing between -Star with high frame rate reconstruction and in both readers.

Conclusion: The use of

-Star with high frame rate reconstruction is a good solution to obtain appropriate AP scan timing compared with Cartesian LAVA. -Star showed equivalent image quality in all phases and in the ratio of appropriate AP scan timing compared with .

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Purpose: To investigate whether shortened acquisition or multiple arterial phase acquisition improves image quality of the arterial phase compared with conventional protocol.

Methods: This retrospective study was approved by the relevant Institutional Review Board. A total of 615 consecutive patients who underwent gadoxetate disodium-enhanced MRI including one of the following three sequences in three different periods were included: (i) conventional liver acquisition with volume acceleration (LAVA) (between October 2014 and January 2015, n = 149), (ii) Turbo-LAVA (between March and August 2016, n = 216), and (iii) differential sub-sampling with Cartesian ordering (

) (between January and September 2015, n = 250). We monitored the respiratory bellows waveform during breath holding for each patient and recorded breath-hold fidelity of the patients. Two radiologists independently evaluated the degree of respiratory artifact and scan timing on the arterial phase and compared them between the three protocols (i.e., conventional LAVA, Turbo-LAVA, and ), with conventional LAVA as control.

Results: The ratio of patients with breath-hold failure was not significantly different among the three protocols (P = 0.6340 and 0.1085). Respiratory artifact was significantly lower in

than in conventional LAVA (P = 0.0424), while there was no significant difference between Turbo-LAVA and conventional LAVA (P = 0.2593). The ratio of adequate scan timing and diagnosable image defined as no or mild artifact and adequate scan timing were higher in than in conventional LAVA (P = 0.0025 and 0.0019), while there was no significant difference between Turbo-LAVA and conventional LAVA (P = 0.0780 and 0.0657).

Conclusion: Compared with conventional protocol, multiple arterial phase acquisition (

) obtained a higher number of diagnosable images by reducing respiratory motion artifact and optimizing the scan timing of arterial phase.

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The size and complexity of software in computer systems and even in consumer electronics is drastically and continuously increasing, thus increasing the compilation time. For example, the compilation time for building some of mobile phones' platform software takes several hours. In order to reduce the compilation time, this paper proposes a Distributed Scalable Compilation Tool, called where full compilation passes such as preprocessing, compilation, and even linking are performed at remote machines, i.e. in parallel. To the best of our knowledge is the first distributed compiler to support complete distributed processing in all the compilation passes. We use an extensive dependency analysis in parsing compilation commands for exploiting higher command-level parallelism, and we apply a file caching method and a network-drive protocol for reducing the remote compilation overhead and simplifying the implementation. Lastly, we minimize load imbalance and remote machine management overhead with our heuristic static scheduling method by predicting compilation time and considering the overheads invoked by the compilation process. Our evaluation using four large mobile applications and eight GNU applications shows that the performance of is scalable and the performance is close to a profile scheduling.

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Rose mallows belong to the Muenchhusia section of the Hibiscus genus. They represent a small group of cold tolerant North American plants and are popular ornamentals mainly because of their abundant, large and colorful flowers. Due to their geographical origin they are well suited for garden use in temperate regions worldwide. The aim of the study was to investigate hybridization barriers in crosses among cultivars of Hibiscus species from the Muenchhusia section: H. coccineus, H. laevis and H. moscheutos. Crossing barriers were identified as both pre- and post-zygotic. The analysis of pollen tube growth revealed inhibition of pollen tubes and their abnormal growth. In specific crosses the fertilization success was low. The pre-fertilization barriers did not cause a complete reproductive isolation between the hybridization partners. In relation to post-fertilization barriers, the occurrence of hybrid incompatibilities such as unviability, chlorosis, necrosis, stunted growth and albinism were the main drawback in production of hybrids. The appearance of symptoms of hybrid incompatibilities was dependent upon specific parental plants. The obtained progeny had intermediate leaf morphology and flower morphology compared to parental plants. Hybridity state was verified by morphological analysis and RAPD markers. Based on the overall plant morphology, 472 hybrid progenies were obtained.

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ALISA means a joint European-Chinese project named “Access to Large Infrastructures for Severe Accidents”. All parties can submit proposals to each other. The submitted proposal as below: In case of a core meltdown accident, molten corium relocated into the lower head of pressure vessel will be ejected into the reactor pit, if the lower head fails. Especially when invessel pressure is higher than the containment pressure, the ejected corium will be finely fragmented. Moreover, if the reactor pit is flooded with water during the vessel failure, fuel coolant interaction (FCI) may occur. The knowledge of FCI is insufficient and consequently the prediction models have large uncertainty. AP1000 use In-Vessel Retention as severe accident mitigation method. Water is injected to the channel between the RPV and insulation in the cavity. There is a quite small space in the cavity of AP1000. This proposal is to see what will happen if IVR fails. is a test facility special for FCI study in KIT that can simulate the high pressure corium eject from the reactor pressure vessel to the containment, which leads to high ejection velocity and high entry velocity into the water pool when the cavity is flooded, which is very unique for FCI investigation. Since the facility simulates also the containment, the experiment can also lead to better understanding on effects of FCI on the containment pressure and its integrity. Such experiment can be useful for FCI code validation.

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ニホンジカの生息個体数の増加や分布拡大により、多くの地域でシカの採食が人工林に深刻な被害を与えている。そこで、若齢スギ造林地に対するシカによる被害リスクを広域で明らかにするため、九州地域を対象として、簡単なシカの痕跡調査 (スギおよびヒノキの成木に対する剥皮痕、シカ糞、下層植生への採食痕の多寡、シカ道および足跡の有無) によって、スギおよびヒノキ人工林に対するシカの影響度合を評価し、若齢スギ造林地へのシカ被害リスクの広域マップを作成した。その結果、九州地域の人工林を対象として、対馬島や玖珠地域などシカの影響を強く受けている地域、シカの拡大最前線など、若齢スギ造林地でのシカ被害に対する適切な管理をすべき地域を抽出することができた。

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ガラス、セラミックス、金属及び複合材などの難加工材を効率的にダイシングするために、超音波振動を援用したダイサーを開発した。本報告では超音波振動エアースピンドル及び超音波ダイシング加工の実例を紹介する。実験結果により、超音波振動は加工負荷を大幅低減でき、また加工効率の向上及びブレード摩耗の低減に有効であることが明らかになった。

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The present paper deals with the fabrication of micro flat drills by precision grinding and their application to the drilling into duralumin and stainless steel with out/with ultrasonic vibration on a vertical grinding/drilling machine. It is found from drill fabrication test that using an objective zoom lens with a magnification of 150-800 of a fiber microscope, the diameters range from 18 to 21 μm, and that precision measurement of the diameter after grinding of drill periphery and the precision positioning enabled us to fabricate a flat drill of minimum diameter 10.8 μm. But, web eccentricity must be improved hereafter. From drill life test it is found that, irrespective of the existence of web taper, the drills without back taper showed longer tool life, and that irrespective of back taper, longer drill life were obtained in case of drills with web taper 4/100. This fact suggests that the stiffness at the root of a drill is very important for drill life. In duralumin longer drill life are gained without ultrasonic vibration than with ultrasonic vibration, and in stainless steel vice versa. Burr grows significantly with the increase in number of holes, but roundness of drilled holes is roughly good.

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