An investigation of the effect of sonic frequency in the removal of volatile organic compounds from soils using a siren-pneumatic fracturing coupled technique

This study investigates the effect of frequency from sonic energy coupled with soil fracturing for the removal of volatile organic compounds from low permeability soils. The laboratory experiments consisted of a test cell, 12 1/2 inches by 12 1/2 inches and 23 3/4 inches high, containing a 1/2 inch geotextile made to simulate the fracture. The pneumatic sound generator used was a siren type generator designed and built at NJIT. Laboratory experiments were performed using the NJJT siren at frequencies of 2957, 6637, 10317, 13997 Hertz and baseline tests with no sound energy were also conducted. The free moisture content was measured by weight loss over time and the concentration of the contaminant was measured by using gas chromatography with a Flame ionization Detector. These measurements were monitored frequently throughout the experiments. The results of this study at different frequencies were analyzed and correlated and were also compared with the results obtained by Fernandez (1997) using the NJIT siren and the whistle. The measurements agreed with those of Fernandez and showed a slight increase in the removal rate constant with a rise in frequency but this improvement was not significant. It was concluded that within the range of frequencies studied, no significant improvement in removal rate can be attributed to frequency. It is recommended that the siren should be reconfigured to operate at higher frequencies (20 kHz) and much higher sound intensities (\u3e 145 dB)

A literature review of suicide research and practices in Taiwan.

Suicide reflects social values and is strongly influenced by the local culture (Farberow, 1975). Some researchers adopt an indigenous psychology approach to analyzing constructs of interest, in which the content and context of the local culture are explicitly considered (Yang, 2000). Suicide in Taiwan is associated with expectations, experiences, and consequences unique to the community. A literature review is conducted to provide an overview of the current status of suicide research and practices in Taiwan, and to assess the extent it is influenced by the indigenous psychology approach

Plane-projection multi-photon microscopy for high-frame-rate Live Tissue Imaging

We present a wide-field multi-photon microscopy that provides optical sectioning at high frame rate under biocompatible laser dosage. Axial resolution comparable to confocal microscopy and 5-frame-per-second live tissue imaging are demonstrated

Long-range mechanical force enables self-assembly of epithelial tubular patterns

Enabling long-range transport of molecules, tubules are critical for human body homeostasis. One fundamental question in tubule formation is how individual cells coordinate their positioning over long spatial scales, which can be as long as the sizes of tubular organs. Recent studies indicate that type I collagen (COL) is important in the development of epithelial tubules. Nevertheless, how cell–COL interactions contribute to the initiation or the maintenance of long-scale tubular patterns is unclear. Using a two-step process to quantitatively control cell–COL interaction, we show that epithelial cells developed various patterns in response to fine-tuned percentages of COL in ECM. In contrast with conventional thoughts, these patterns were initiated and maintained by traction forces created by cells but not diffusive factors secreted by cells. In particular, COL-dependent transmission of force in the ECM led to long-scale (up to 600 μm) interactions between cells. A mechanical feedback effect was encountered when cells used forces to modify cell positioning and COL distribution and orientations. Such feedback led to a bistability in the formation of linear, tubule-like patterns. Using micro-patterning technique, we further show that the stability of tubule-like patterns depended on the lengths of tubules. Our results suggest a mechanical mechanism that cells can use to initiate and maintain long-scale tubular patterns

Long-range mechanical force in colony branching and tumor invasion

The most concerned factors for cancer prognosis are tumor invasion and metastasis. The patterns of tumor invasion can be characterized as random infiltration to surrounding extracellular matrix (ECM) or formation of long-range path for collective migration. Recent studies indicate that mechanical force plays an important role in tumor infiltration and collective migration. However, how tumor colonies develop mechanical interactions with each other to initiate various invasion patterns is unclear. Using a micro-patterning technique, we partition cells into clusters to mimic tumor colonies and quantitatively induce colony-ECM interactions. We find that pre-malignant epithelial cells, in response to concentrations of type I collagen in ECM ([COL]), develop various branching patterns resembling those observed in tumor invasion. In contrast with conventional thought, these patterns require long-range (~ 600 μm) transmission of traction force, but not biochemical factors. At low [COL], cell colonies synergistically develop pairwise and directed branching mimicking the formation of long-range path. By contrast, at high [COL] or high colony density, cell colonies develop random branching and scattering patterns independent of each other. Our results suggest that tumor colonies might select different invasive patterns depending on their interactions with each other and with the ECM

COMPARING THE DIFFERENCE BETWEEN FRONT-LEG AND BACK-LEG ROUND-HOUSE KICKS ATIACKING MOVEMENT ABILITIES IIN TAEKWONDO

The purpose of this study is to compare front-leg and back-leg movement abilities in Taekwondo athletes with a weight level of less than 68 kg. Six male subjects (age: 19.8±1, height: 175.6±3.9, weight: 62.5±4.8) conducted back-leg attacking movements and front-leg attacking movements with their dominant leg. The back-leg attacking movements include back leg round-house kick and strike back round house kick. The front-leg attacking movements include front leg round-house kick and slide round-house kick. From statistics obtained, the kicking of relative force, compound acceleration, and tangential acceleration are better for back-leg attacking movements. However, front-leg attacking movements are better in tangential velocity. The range of waist a rotation and the flexibility of the hip joint are important to roundhouse kick techniques to the kinetic chain