Evaluation of physical workload affected by mass and center of mass of head-mounted display

金沢大学新学術創成研究機構Embargo Periods 12 Month

Oligodendrocyte Precursor Cells Support Blood-Brain Barrier Integrity via TGF-β Signaling

Trophic coupling between cerebral endothelium and their neighboring cells is required for the development and maintenance of blood-brain barrier (BBB) function. Here we report that oligodendrocyte precursor cells (OPCs) secrete soluble factor TGF-β1 to support BBB integrity. Firstly, we prepared conditioned media from OPC cultures and added them to cerebral endothelial cultures. Our pharmacological experiments showed that OPC-conditioned media increased expressions of tight-junction proteins and decreased in vitro BBB permeability by activating TGB-β-receptor-MEK/ERK signaling pathway. Secondly, our immuno-electron microscopic observation revealed that in neonatal mouse brains, OPCs attach to cerebral endothelial cells via basal lamina. And finally, we developed a novel transgenic mouse line that TGF-β1 is knocked down specifically in OPCs. Neonates of these OPC-specific TGF-β1 deficient mice (OPC-specific TGF-β1 partial KO mice: PdgfraCre/Tgfb1flox/wt mice or OPC-specific TGF-β1 total KO mice: PdgfraCre/Tgfb1flox/flox mice) exhibited cerebral hemorrhage and loss of BBB function. Taken together, our current study demonstrates that OPCs increase BBB tightness by upregulating tight junction proteins via TGF-β signaling. Although astrocytes and pericytes are well-known regulators of BBB maturation and maintenance, these findings indicate that OPCs also play a pivotal role in promoting BBB integrity

Development of a High-intensity Focused Ultrasound Exposure Device for Reducing Skin Burn Risk

High-intensity focused ultrasound（HIFU）can non-invasively irradiate inside the body. However, when used to treat fetuses, it can cause thermal burns of the mother’s abdominal wall at the skin interface. This study was carried out to determine whether a modified HIFU transducer enabling split-aperture irradiation can prevent thermal burns. Two HIFU transducers were compared: a conventional transducer using full-aperture irradiation and a modified transducer using split-aperture irradiation. The modified transducer was divided into six sectors for split-aperture irradiation and had a larger surface area and a smaller F number（focal length/aperture diameter）than the conventional transducer. HIFU was delivered to eight sites on the left and right leg of a three-month-old baby pig under general anesthesia, and the sites were assessed for thermal burning by two or more dermatologists. The same person performed all irradiations. Full-aperture irradiation with the conventional transducer caused deep dermal burns at all target sites, while split-aperture irradiation with the modified transducer caused only epidermal burns or superficial dermal burns. Split-aperture irradiation using a modified HIFU transducer with six sectors and a smaller F number reduces the severity of skin burns, and thus will improve the safety of HIFU therapy

Trends in life science grid: from computing grid to knowledge grid

BACKGROUND: Grid computing has great potential to become a standard cyberinfrastructure for life sciences which often require high-performance computing and large data handling which exceeds the computing capacity of a single institution. RESULTS: This survey reviews the latest grid technologies from the viewpoints of computing grid, data grid and knowledge grid. Computing grid technologies have been matured enough to solve high-throughput real-world life scientific problems. Data grid technologies are strong candidates for realizing "resourceome" for bioinformatics. Knowledge grids should be designed not only from sharing explicit knowledge on computers but also from community formulation for sharing tacit knowledge among a community. CONCLUSION: Extending the concept of grid from computing grid to knowledge grid, it is possible to make use of a grid as not only sharable computing resources, but also as time and place in which people work together, create knowledge, and share knowledge and experiences in a community

Analysis of Postural Instability in the Upright Position on Narrow Platforms and the Interactions with Postural Constraints

Background: Loss of balance is a considerable risk factor for workers while using ladders, because they are required to maintain static postural balance on platforms of a restricted size. This study observed center of mass (CoM) and center of pressure (CoP) behaviors and evaluated the effects of the platform depth (anterior–posterior length) and working postures. Methods: Eleven male participants stood on four platforms with depths ranging from 6 to 15 cm and maintained their positions for 60 s while performing or not performing other tasks (object holding, upward viewing, or both simultaneously). The kinematics were analyzed on the sagittal plane based on the inverse pendulum model. Results: The absolute moving range for the CoP–CoM linearly increased with the decreasing platform depth, and the working postures affected the slopes of the linear fits. The relative range of CoP–CoM displacement on narrow platforms was highly correlated with the subjective sense of instability. Conclusions: Monitoring the CoP is effective for a better understanding and evaluation of static postural balance. This study’s findings contribute to improving the design of work equipment through the use of wider platforms that are robust against the effects of working postures

Adorption Enhancement of Rectangular Packed Bed with Spherical Adonrbent by Side Wall Cooling in a Forced Convection Flow

The present paper has dealt with the one-sidewall cooling effect of spherical adsorbent paticles packed in a rectangular bed on water vapor adsorption characteristics by a 2-dimensional numerical analysis. The analysis model was considered that one-sidewall of a rectangular packed bed with the homogeneous spherical silica-gel particles was cooled and another walls were adiabatic. The moist air flowed into the rectangular packed bed with spherical adsorbent particles. The silica-gel B with high adsorption ability over high relative humidity was selected as a suitable adsorbent. Numerical results revealed the effects of moist air inlet humidity and airflow velocity, size of spherical silica-gel particles and width of the rectangular packed bed and the sidewall cooling terperature on the amount of water vapor adsorption.住宅・ビル空調分野では、省エネルギーの促進や室内空気質そしてアメニテイ性の向上が米国やカナダように一部義務付けている状況あり、今後室内空気の調湿や換気に伴う空調負荷の増大が予想される。このような背景のもとに、大量に賦存する低温排熱の利用、省エネルギー促進そして室内空気環境の快適性志向をカバーする環境親和型熱技術（グリーンサーモテクノロジー）の最右翼である熱サイクル機器として、吸着剤を用いた吸着熱式冷凍機やヒートポンプそして調湿機やデシカントクーリング機器等がある。吸着剤を用いたヒートサイクルは、古くて新しい技術で、環境に優しい技術と言うことで米国や欧州等で開発普及が進んでおり、我が国の代替冷媒を用いた蒸気圧縮機型冷凍機の展開と対比するものである。これら吸着剤を用いた空調関連の調湿や調温利用以外に、吸着剤の水蒸気の吸着及び脱着過程において、水分の蒸発・凝縮潜熱に相当する多量の熱授受があることから、吸着剤は蓄熱材として利用の可能性がある。特に高温多湿な我が国の気候環境においては、湿り空気中の水蒸気を吸着剤に吸着（除湿）する際に発生する吸着熱（放熱）を暖房熱源等へ利用し、その脱着再生（加湿）においては排熱や太陽熱等を利用する、いわゆる化学蓄熱の構築が可能となる。従って、本基礎研究は、一般に普及している低温脱着が可能なシリカゲル吸着剤を蓄熱剤として利用することを前提として、まず冷却による平衡状態に至る吸着特性向上を数値計算で検討するものである。対象とする吸着系は、球状吸着剤を充填した矩形充填層に湿り空気を流動させるもので、吸着性能向上特性は矩形充填層側壁からの冷却による効果を種々の因子（冷却温度、湿り空気流入湿度、平均空気速度、球状吸着剤粒子直径や充填層の寸法）のもとで明らかにするものである