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1.
Sci Adv ; 10(19): eadl2413, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38728402

RESUMEN

The existence of molecular H2O and evolution of solar wind-derived water on the lunar surface remain controversial. We report that large amounts of OH and molecular H2O related to solar wind and other multiple sources are preserved in impact glasses from Chang'e-5 (CE5) lunar soil based on reflectance infrared spectroscopy and nanoscale secondary ion mass spectrometry analyses. The estimated water content contributed by impact glasses to CE5 lunar soil was ~72 ppm, including molecular H2O of up to 15 to 25 ppm. Our studies revealed that impact glasses are the main carrier of molecular H2O in lunar soils. Moreover, water in CE5 impact glasses provides a record of complex formation processes and multiple water sources, including water derived from solar wind, deposited by water-bearing meteorites/micrometeorites, and inherited from lunar indigenous water. Our study provides a better understanding of the evolution of surficial water on airless bodies and identifies potential source and storage pathways for water in the terrestrial planets.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38064604

RESUMEN

Objective: To investigate the effects of task-oriented biomechanical sensors-balance training on lower limb motor function and gait balance function in stroke patients with hemiplegia. Methods: Researchers divided 106 stroke patients with hemiplegia into observation and control groups. All received essential rehabilitation training treatment. The observation group's rehabilitation consisted of task-oriented biomechanical sensors-balance training. The modified Ashworth Scale score, FuGL-Meyer Motor Function Scale score, and other indicators measured the results of the two groups. Results: The Berg balance scale score and FuGL-Meyer Motor Function Scale score in the observation group were higher than in the control group (P < .05). The modified Ashworth Scale score of the triceps calf muscle in the observation group was significantly lower than that in the control group (P < .05). The observation group's step length, step frequency, maximum angle of hip extension, and knee flexion exceeded those of the control group. In contrast, the maximum angle of knee extension was smaller than those in the control group (P < .05). Conclusion: Basic rehabilitation training combined with task-oriented biomechanical perception-balance training can improve the lower limb motor function of stroke patients with hemiplegia.

3.
Nat Commun ; 13(1): 5336, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36088436

RESUMEN

The formation and distribution of lunar surficial water remains ambiguous. Here, we show the prominence of water (OH/H2O) attributed to solar wind implantation on the uppermost surface of olivine, plagioclase, and pyroxene grains from Chang'E-5 samples. The results of spectral and microstructural analyses indicate that solar wind-derived water is affected by exposure time, crystal structure, and mineral composition. Our estimate of a minimum of 170 ppm water content in lunar soils in the Chang'E-5 region is consistent with that reported by the Moon Minerology Mapper and Chang'E-5 lander. By comparing with remote sensing data and through lunar soil maturity analysis, the amount of water in Chang'E-5 provides a reference for the distribution of surficial water in middle latitude of the Moon. We conclude that minerals in lunar soils are important reservoirs of water, and formation and retention of water originating from solar wind occurs on airless bodies.

4.
Nanomaterials (Basel) ; 12(7)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35407250

RESUMEN

Irradiation structural damage (e.g., radiation tracks, amorphous layers, and vesicles) is widely observed in lunar soil grains. Previous experiments have revealed that irradiation damage is caused by the injection of solar wind and solar flare energetic particles. In this study, cordierite and gabbro were selected as analogs of shallow and deep excavated lunar crust materials for proton irradiation experiments. The fluence was 1.44 ± 0.03 × 1018 H+/cm2, which is equivalent to 102 years of average solar wind proton implantation on the Moon. Before and after irradiation, structural damage in samples is detected by slow positron annihilation technology (PAT), Doppler broadening (DB) measurement, focused ion beam (FIB), and transmission electron microscopy (TEM). The DB results showed the structural damage peaks of irradiated gabbro and cordierite were located at 40 and 45 nm. Hydrogen diffused to a deeper region and it reached beyond depths of 150 and 136 nm for gabbro and cordierite, respectively. Hydrogen atoms occupied the original vacancy defects and formed vacancy sites-hydrogen atom complexes, which affected the annihilation of positrons with electrons in the vacancy defects. All of the DB results were validated by TEM. This study proves that the positron annihilation technique has an excellent performance in the detection of defects in the whole structure of the sample. In combination with TEM and other detection methods, this technology could be used for the detection of structural damage in extraterrestrial samples.

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