143 research outputs found
Principal horizontal stress orientations prior to the 2011 Mw 9.0 Tohoku-Oki, Japan, earthquake in its source area
Coupled Simulation of Seismic Wave Propagation and Failure Phenomena by Use of an MPS Method
Exploring deep microbial life in coal-bearing sediment down to ~2.5 km below the ocean floor
Peer reviewedPostprin
Occupational therapy using a robotic-assisted glove ameliorates finger dexterity and modulates functional connectivity in amyotrophic lateral sclerosis.
Introduction:Although rehabilitation is recommended for amyotrophic lateral sclerosis (ALS), improvement of functional decline has hardly been achieved. We investigated the effect of occupational therapy that uses a robotic-assisted glove (RAG) on hand dexterity and the functional connectivities found in the brain of ALS patients.Method:Ten patients diagnosed with ALS and admitted to the Shiga University of Medical Science (SUMS) Hospital from December 2018 to December 2021 participated in the study. These participants chose the hand side to wear RAG and exercised for two weeks. A sham movement was performed on the other side. We administered several functional assessments, including the Simple Test for Evaluating Hand Function (STEF), grip strength, pinch meter for grip strength, Canadian occupational performance measure (COPM), as well as nerve conduction study (NCS) before and after the exercise, and evaluated the results. We also analyzed six patients\u27 resting-state functional magnetic resonance imaging (rs-fMRI).Results:Two-week robotic rehabilitation improved the STEF, grip strength, and COPM scores when compared with those of the other side. However, no significant effect was observed in the pinch meter and the NCS results. The rs-fMRI data analysis revealed that the robotic rehabilitation augmented two functional connectivities between the left pallidum-right supplementary motor cortex and right insular cortex-right sensorimotor network among the patients, which had beneficial effects.Conclusion:The occupational therapy using RAG displayed improved hand dexterity. The enhanced functional connectivities around the sensorimotor network might be associated with the improvement in hand dexterity because of the RAG
An attenuated vaccinia vaccine encoding the severe acute respiratory syndrome coronavirus-2 spike protein elicits broad and durable immune responses, and protects cynomolgus macaques and human angiotensin-converting enzyme 2 transgenic mice from severe acute respiratory syndrome coronavirus-2 and its variants
As long as the coronavirus disease-2019 (COVID-19) pandemic continues, new variants of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) with altered antigenicity will emerge. The development of vaccines that elicit robust, broad, and durable protection against SARS-CoV-2 variants is urgently required. We have developed a vaccine consisting of the attenuated vaccinia virus Dairen-I (DIs) strain platform carrying the SARS-CoV-2 S gene (rDIs-S). rDIs-S induced neutralizing antibody and T-lymphocyte responses in cynomolgus macaques and human angiotensin-converting enzyme 2 (hACE2) transgenic mice, and the mouse model showed broad protection against SARS-CoV-2 isolates ranging from the early-pandemic strain (WK-521) to the recent Omicron BA.1 variant (TY38-873). Using a tandem mass tag (TMT)-based quantitative proteomic analysis of lung homogenates from hACE2 transgenic mice, we found that, among mice subjected to challenge infection with WK-521, vaccination with rDIs-S prevented protein expression related to the severe pathogenic effects of SARS-CoV-2 infection (tissue destruction, inflammation, coagulation, fibrosis, and angiogenesis) and restored protein expression related to immune responses (antigen presentation and cellular response to stress). Furthermore, long-term studies in mice showed that vaccination with rDIs-S maintains S protein-specific antibody titers for at least 6 months after a first vaccination. Thus, rDIs-S appears to provide broad and durable protective immunity against SARS-CoV-2, including current variants such as Omicron BA.1 and possibly future variants
Indian Monsoonal Variations During the Past 80 Kyr Recorded in NGHP-02 Hole 19B, Western Bay of Bengal: Implications From Chemical and Mineral Properties
金沢大学理工研究域地球社会基盤学系Detailed reconstruction of Indian summer monsoons is necessary to better understand the late Quaternary climate history of the Bay of Bengal and Indian peninsula. We established a chronostratigraphy for a sediment core from Hole 19B in the western Bay of Bengal, extending to approximately 80 kyr BP and examined major and trace element compositions and clay mineral components of the sediments. Higher δ 18 O values, lower TiO 2 contents, and weaker weathering in the sediment source area during marine isotope stages (MIS) 2 and 4 compared to MIS 1, 3, and 5 are explained by increased Indian summer monsoonal precipitation and river discharge around the western Bay of Bengal. Clay mineral and chemical components indicate a felsic sediment source, suggesting the Precambrian gneissic complex of the eastern Indian peninsula as the dominant sediment source at this site since 80 kyr. Trace element ratios (Cr/Th, Th/Sc, Th/Co, La/Cr, and Eu/Eu*) indicate increased sediment contributions from mafic rocks during MIS 2 and 4. We interpret these results as reflecting the changing influences of the eastern and western branches of the Indian summer monsoon and a greater decrease in rainfall in the eastern and northeastern parts of the Indian peninsula than in the western part during MIS 2 and 4. © 2018. American Geophysical Union. All Rights Reserved
In-situ mechanical weakness of subducting sediments beneath a plate boundary décollement in the Nankai Trough
© 2018, The Author(s). The study investigates the in-situ strength of sediments across a plate boundary décollement using drilling parameters recorded when a 1180-m-deep borehole was established during International Ocean Discovery Program (IODP) Expedition 370, Temperature-Limit of the Deep Biosphere off Muroto (T-Limit). Information of the in-situ strength of the shallow portion in/around a plate boundary fault zone is critical for understanding the development of accretionary prisms and of the décollement itself. Studies using seismic reflection surveys and scientific ocean drillings have recently revealed the existence of high pore pressure zones around frontal accretionary prisms, which may reduce the effective strength of the sediments. A direct measurement of in-situ strength by experiments, however, has not been executed due to the difficulty in estimating in-situ stress conditions. In this study, we derived a depth profile for the in-situ strength of a frontal accretionary prism across a décollement from drilling parameters using the recently established equivalent strength (EST) method. At site C0023, the toe of the accretionary prism area off Cape Muroto, Japan, the EST gradually increases with depth but undergoes a sudden change at ~ 800 mbsf, corresponding to the top of the subducting sediment. At this depth, directly below the décollement zone, the EST decreases from ~ 10 to 2 MPa, with a change in the baseline. This mechanically weak zone in the subducting sediments extends over 250 m (~ 800–1050 mbsf), corresponding to the zone where the fluid influx was discovered, and high-fluid pressure was suggested by previous seismic imaging observations. Although the origin of the fluids or absolute values of the strength remain unclear, our investigations support previous studies suggesting that elevated pore pressure beneath the décollement weakens the subducting sediments. [Figure not available: see fulltext.]
Coupled Simulation of Seismic Wave Propagation and Failure Phenomena by Use of an MPS Method
The failure of brittle materials, for example glasses and rock masses, is commonly observed to be discontinuous. It is, however, difficult to simulate these phenomena by use of conventional numerical simulation methods, for example the finite difference method or the finite element method, because of the presence of computational grids or elements artificially introduced before the simulation. It is, therefore, important for research on such discontinuous failures in science and engineering to analyze the phenomena seamlessly. This study deals with the coupled simulation of elastic wave propagation and failure phenomena by use of a moving particle semi-implicit (MPS) method. It is simple to model the objects of analysis because no grid or lattice structure is necessary. In addition, lack of a grid or lattice structure makes it simple to simulate large deformations and failure phenomena at the same time. We first compare analytical and MPS solutions by use of Lamb’s problem with different offset distances, material properties, and source frequencies. Our results show that analytical and numerical seismograms are in good agreement with each other for 20 particles in a minimum wavelength. Finally, we focus our attention on the Hopkinson effect as an example of failure induced by elastic wave propagation. In the application of the MPS, the algorithm is basically the same as in the previous calculation except for the introduction of a failure criterion. The failure criterion applied in this study is that particle connectivity must be disconnected when the distance between the particles exceeds a failure threshold. We applied the developed algorithm to a suspended specimen that was modeled as a long bar consisting of thousands of particles. A compressional wave in the bar is generated by an abrupt pressure change on one edge. The compressional wave propagates along the interior of the specimen and is visualized clearly. At the other end of the bar, the spalling of the bar is reproduced numerically, and a broken piece of the bar is formed and falls away from the main body of the bar. Consequently, these results show that the MPS method effectively reproduces wave propagation and failure phenomena at the same time
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