Influence of spatial structure migration of overlying strata on water storage of underground reservoir in coal mine.

Underground reservoir technology for coal mines can realize the coordinated development of coal exploitation and water protection in water-shortage-prone areas. The seepage effect of the floor seriously affects the safety of underground reservoirs under the action of mining damage and seepage pressure. Focusing on the problem of floor seepage in underground reservoirs, a spatial mechanical model of underground reservoirs was established.

A Multistimuli Responsive, Flexible Luminescent Framework and Its Applicability in Anticounterfeiting.

A linear distyrylanthracene derivative (DDATAn) with two diaminotriazine (DAT) groups acting as the hydrogen bond (H-bond) units was designed and synthesized in order to construct flexible organic porous crystals. H-bonds between the DAT moieties helped the molecules to construct a double interpenetrated two-dimensional layer, and the stacking between layers provided a H-bonded organic framework (X-HOF-3) with one-dimensional solvent channels. When X-HOF-3 was placed in contact with methanol, the fluorescent colors of the HOF exhibited an apparent bathochromic shift.

Tunable Fluorescence in Two-Component Hydrogen-Bonded Organic Frameworks Based on Energy Transfer.

A dumbbell-shaped compound (TPAD) with four 2,4-diaminotriazine moieties as H-bond units and a benzene ring as a bridge group was found to form hydrogen-bonded organic frameworks (HOFs) with strong cyan fluorescence. An energy acceptor, 6,6',6″,6‴-(((benzo[][1,2,5]thiadiazole-4,7-diylbis-(4,1-phenylene))bis(azanetriyl))tetrakis(benzene-4,1-diyl))tetrakis(1,3,5-triazine-2,4-diamine) (BTAD), with the same molecular skeleton as TPAD and a longer emission wavelength could homogeneously distribute within the framework of TPAD through occupying the locations of TPAD. As a result, two-component HOFs (TC-HOFs) were formed.

Guest-Regulated Luminescence and Force-Stimuli Response of a Hydrogen-Bonded Organic Framework.

Guest molecules may endow porous materials with new or enhanced properties as well as functions. Here, a porous hydrogen-bonded organic framework (HOF) constructed from a three-armed triphenylamine derivative is used to investigate how guests regulate photoluminescence and trigger force-stimuli response. It was found that guest solvents in pores might regulate HOF's luminescence.

Tests of models for saccade-vergence interaction using novel stimulus conditions.

During natural activities, two types of eye movements - saccades and vergence - are used in concert to point the fovea of each eye at features of interest. Some electrophysiological studies support the concept of independent neurobiological substrates for saccades and vergence, namely saccadic and vergence burst neurons. Discerning the interaction of these two components is complicated by the near-synchronous occurrence of saccadic and vergence components.

Vestibular and non-vestibular contributions to eye movements that compensate for head rotations during viewing of near targets.

Geometry dictates that when subjects view a near target during head rotation the eyes must rotate more than the head. The relative contribution to this compensatory response by adjustment of the vestibulo-ocular reflex gain (Gvor), visual tracking mechanisms including prediction, and convergence is debated. We studied horizontal eye movements induced by sinusoidal 0.

Comparison of velocity waveforms of eye and head saccades.

We compared the velocity waveforms of head and eye-in-head movements during eye-head saccades over a range 5-50 degrees. The velocity waveforms of eye-in-head saccades showed a skew ratio (acceleration period/saccade duration) that varied as a function of saccade size and duration. The velocity waveforms of head saccades showed a more constant skew of approximately 0.

Tests of Hering- and Helmholtz-type models for saccade-vergence interactions by comparing visually guided and memory-guided movements.

We compared the dynamic properties of memory-guided and visually-guided saccade-vergence movements. For memory-guided responses, convergence components were slowed proportionally more than corresponding saccadic components, compared with visually-guided responses. This result is consistent with independent saccadic and vergence systems, and supports a Hering-type model for saccade-vergence interactions.

Effects of retinal image slip on modulation of visual vestibulo-ocular reflex during near viewing.

During viewing of a near target, the gain of the visually modulated vestibulo-ocular reflex (vVOR) exceeds 1.0. We investigated whether retinal image slip contributes to this gain increase by measuring responses during strobe illumination.

Evaluating large saccades in patients with brain-stem or cerebellar disorders.

Clinicians conventionally test saccades at the bedside by noting the accuracy, initiation time, and speed of large movements, with the patient's head stationary. Partly for methodological reasons, laboratory analysis of saccades has mainly focused on movements of 20 degrees or less. By measuring the velocity waveform of large saccades, it is possible to examine more closely the way in which brain stem and cerebellum guide the eye to the target.

Effects of eyelid closure, blinks, and eye movements on the electroencephalogram.

Objective: To characterize the effects of the eyeball and eyelid positions during eyeblinks on electroencephalographic (EEG) potentials.

Methods: Movements of the upper eyelids and eyes were measured in two healthy subjects using the magnetic search coil technique during horizontal and vertical eye rotations, eyeblinks, and lid closure. Corresponding signal changes were recorded simultaneously on the electroencephalogram (EEG).

Directional asymmetry during combined saccade-vergence movements.

We investigated relationships between saccadic and vergence components of gaze shifts as 10 human subjects switched visual fixation between targets aligned in the midsagittal plane that lay in different vertical directions and at different distances. When fixation was shifted between a higher distant target and a lower near target, peak convergence velocity followed peak vertical saccadic velocity by a median interval of 12 ms. However, when fixation was shifted between a lower distant target and a higher near target, peak convergence velocity followed peak vertical saccadic velocity by a median interval of 76 ms.

Evaluating small eye movements in patients with saccadic palsies.

Slow saccades are an important diagnostic feature of a range of degenerative, metabolic, and genetic diseases of the nervous system. Many affected patients have difficulty initiating saccades, and the movements themselves may be small, making it difficult to make comparisons with control subjects. A large-field optokinetic stimulus may elicit quick phases of nystagmus in patients who cannot initiate voluntary saccades, but these movements may also be small.

Vertical optokinetic nystagmus and saccades in normal human subjects.

Purpose: Optokinetic stimulation induces nystagmus that can be used to test the saccadic and visual-tracking systems in some patients with voluntary gaze palsies. The purpose of this study was to characterize vertical optokinetic nystagmus (OKN) in normal human subjects, comparing the dynamic properties of the quick phases with voluntary saccades of similar size and measuring the slow-phase responses to visual stimuli with a range of spatial and temporal frequencies.

Methods: Vertical OKN and saccades were recorded in 10 healthy adult subjects (age range, 24-54 years) using the magnetic search coil technique.

Disorders of vertical optokinetic nystagmus in patients with ocular misalignment.

Purpose: To compare responses to vertical and horizontal optokinetic (OK) stimulation in patients with disorders of ocular alignment.

Methods: Using the magnetic search coil technique, we measured horizontal and vertical rotations of both eyes in six patients with strabismus since childhood and eight normal subjects. The OK stimulus subtended 72 degrees horizontally and 60 degrees vertically, consisted of black-and-white stripes with a spatial frequency of 0.

Properties of anticipatory vergence responses.

Purpose: To characterize the dynamic properties of vergence eye movements made between near and far targets that were alternately illuminated with predictable timing.

Methods: Using the magnetic search coil technique, eye movements were measured in 10 normal subjects as they shifted their point of fixation between a near green LED and a distant red laser spot, both aligned on subjects' midlines. Targets were alternately illuminated every 1.