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The soil water characteristic curve (SWCC) describes the relationship between matric suction and moisture of soil, the testing process of which is time-consuming. The test time of particle size distribution (PSD), in contrast, is relatively short. Thus, it is quite important to establish a proper model for PSD to forecast SWCC. This paper analyzed PSD of 25 groups of loess by way of laser diffraction technique (LD) and sieve-settlement method. Works were carried out on fitting analysis on PSD with Logarithmic model, Fredlund model, Jaky model, and Gompertz model. Statistical method was used to explain the fitting performance. Meanwhile, an empirical model was put forward. Compared to the four models, the empirical model has fewer parameters, simple model form, and smaller fluctuations of parameters. Results of LD showed higher clay content but lower silt content. It is suggested that Fredlund model or the empirical model be adopted to forecast SWCC of Malan loess. [ABSTRACT FROM AUTHOR]

A remarkable risk in the field of rock engineering is the natural exposure of low-grade metamorphic rock to the freeze-thaw process. Examples of such materials are slate and phyllite, which are employed approximately mountainous permafrost zones. In order to study the weathering processes and mechanisms in low-grade metamorphic rock following freeze-thaw weathering processes, the freeze-thaw cycles were applied. Accordingly to this process, low-grade metamorphic rock partially or completely deteriorates, and mechanical properties, microstructure, and mineral content changes are commonly associated with freeze-thaw processes. This study shows that, following numerous freeze-thaw cycles processes, the quality, wave velocity, and compressive strength of rock reduce; calcite, mica, feldspar, and pyrite contents decrease; and clay minerals and gypsum content increase. Furthermore, the study also demonstrated that the changes in quality, wave velocity, and compressive strength caused by weathering of the rock followed the sequence slate > phyllite. However, the mineral contents of slate and phyllite alter in the same way. Because of this increase in volume and subsequent F-T cycles, new cracks form on the surfaces of pores due to outward pressure, and a lot of water is absorbed by clay minerals. The amount of water increases once again due to freezing as the temperature falls below zero degrees Celsius. This course duplicates with cyclic temperature changes and causes deterioration of low-grade metamorphic rock materials. By analysis of an examination of the damage variables based on wave velocity, it is possible to conclude that mineral changes during the freeze-thaw effect may make for the formation of voids and the deterioration of metamorphic rock. This research contributes to a better understanding of weathering processes and mechanisms of low-grade metamorphic rock following freeze-thaw weathering processes. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) decreases the quality of life of the affected individuals. The incidence of PD is expected to increase given the growing aging population. Motor symptoms associated with PD render the patients unable to self-care and function properly. Given that several drugs have been developed to control motor symptoms, highly sensitive scales for clinical evaluation of drug efficacy are needed. Among such scales, the objective and continuous evaluation of wearable devices is increasingly utilized by clinicians and patients. Several electronic technologies have revolutionized the clinical monitoring of PD development, especially its motor symptoms. Here, we review and discuss the recent advances in the development of wearable devices for bradykinesia, tremor, gait, and myotonia. Our aim is to capture the experiences of patients and clinicians, as well as expand our understanding on the application of wearable technology. In so-doing, we lay the foundation for further research into the use of wearable technology in the management of PD. [ABSTRACT FROM AUTHOR]

Two scale-model tests were separately conducted in standard Toyoura sand with relative density of 50% and 80%. The effect of sand relative density on pile-soil interaction was investigated through the response of a laterally loaded pile and the sand movement around the pile. At a displacement of 3.6 mm of the loading point, the applied loads in loose and dense sand were 4.775 N and 21.025 N, respectively, and the maximum moment and soil resistance of the pile in dense sand were over 4 times those in loose sand. However, the deflection of the pile in dense sand was less than that in loose sand; additionally, the depth of zero deflection in dense sand was also less than that in loose sand. At the same time, the maximum displacements of loose sand in the vertical profile and ground surface were over 1.5 times those of dense sand. These characteristics occurred because the relative stiffness ratio of soil and pile increased as the relative density increased, which caused the behavior of the pile in dense sand to be elastic rather than rigid. In addition, the compacted sand particles did not move as easily as the loose sand particles. [ABSTRACT FROM AUTHOR]