ABSTRACT
Pectus excavatum (PE) is a congenital defect that presents with an anterior depression of the chest wall, which can impact cardiopulmonary function. A 25-year-old hypermobile male presented with a history of PE and chronic dyspnea on exertion, chronic cough, and intermittent chest wall pain. This study explores osteopathic manipulative treatment (OMT) as a possible alternative to improve symptoms associated with PE. Osteopathic structural exam (OSE), volumetric measurements of the thoracic cavity, vitals, and pulmonary function tests were evaluated at baseline and after OMT. The patient was treated with 14 weeks of weekly OMT for his exertional dyspnea, cough, and chest wall pain. Somatic dysfunctions were addressed through OMT, which all improved by the end of the 14-week treatment. Notably, the excursion at the sternal angle increased by threefold after complete treatment. The patient reported subjective improvement in all symptoms, with durable improvement in chest wall pain at 10 months after cessation of treatment. The application of OMT can help alleviate symptoms of pectus excavatum and aid in the management of patients who have not received surgical interventions.
ABSTRACT
In the present paper, the time evolution study on slip soils treated by different proportions of ionic soil stabilizer (ISS) water solution was conducted by the LIBS system and the relationship between the cation exchange and such engineering properties of reinforcing soil as plasticity index, cohesive force and coefficient of compressibility were analyzed. The results showed that the cation exchange velocity of the proportion of 1:200 ISS reinforcing soil is the fastest among the three proportions (1:100, 1:200 and 1:300) and the modification effect of engineering performance index is quite obvious. These studies provide an experimental basis for the ISS applied to curing project, and monitoring geotechnical engineering performance by LIBS technology also provides a new way of thinking for the curing project monitoring.
ABSTRACT
The wastewater from industrial smelting process contains heavy metals such as arsenic (As) that produce serious environmental pollution and cause actual harm to the health of people. It is necessary to control the pollution at the source and achieve a real-time and online monitoring. The laser-induced breakdown spectroscopy (LIBS) is a new elemental analysis technique, and has the advantage of rapid detection. An LIBS setup has been established. The Nd : YAG laser beam is focused onto the sample, then the plasmas are produced. The emission spectra of plasmas are dispersed by an Echelle spectrograph and detected by an intensified charge-coupled device (ICCD). Experiments have been carried out on the industrial wastewater collected from the scene. The spectral lines of As element were obtained. The calibration curve of the line intensities versus the concentrations of the As element was acquired by the experiment. The calibration curve can be used for the quantitative analysis of arsenic element with an unknown concentration in the industrial wastewater. The results showed that the LIBS technique can be applied in the rapid detection of As element in industrial wastewater, and has wide range of applications.
ABSTRACT
The glucose solution was broken down by focusing the 1.064 microm beam of a Nd : YAG laser, and the plasma was produced. The spectral signals were detected by an experimental setup including spectrograph and ICCD. The spectral line at 247.86 nm was identified as the characteristic of glucose by contrasting the spectra of glucose solution and pure water. Comparing the spectral intensities of three kinds of glucose solution with different concentrations (3%, 6% and 9%), the experimental result showed that the bigger the concentration, the stronger the spectral intensity,and the characteristic spectral intensities with the three concentrations present the trend of logarithm increase. At the same concentration, the time evolution curve of the characteristic spectra was obtained by changing the delay time of ICCD. It is concluded that the intensity of the characteristic spectra first increases and then decreases with the delay time. With the glucose solution concentration altering, the decay time of the characteristic spectra is nearly fixed, meaning that the decay time is independent of the concentration. The decay time of the characteristic spectra is about 300 ns. Furthermore, it was found that the characteristic spectral intensities of glucose solution with different concentrations reach the maximum at the same delay time.
ABSTRACT
Laser-induced breakdown spectroscopy is a new technology of elementary analysis, and it will be used in coal analysis. The delay time of signal is an important parameter of spectral analysis. A LIBS system was set up and three kinds of coal (Jiangxipingxiang coal, Shanxixishan coal and Guizhoupingzhai coal) were chosen for this investigation. The spectra in the range of 240 to 250 nm and 275 to 290 nm of the each three coal samples are shown and they record several spectral lines of components such as C, Mg and Si according to the NIST database. The temporal evolution of SNR of spectral line was obtained, and the value of SNR increased with the time delay, then decayed. The temporal evolution of SNR was different as the coal, element and spectral line differs. Finally, optimum delay time of each spectral lines of elements in the coal samples was calculated according to the biggest value of signal-to-noise ratio, and the relation between the characteristic of coal, element, spectral line and the op timum delay time was analyzed.
ABSTRACT
An 1. 06 microm Nd : YAG laser beam (energy: -500 mJ/pulse, pulse width: 10 ns, repetition rate: 30 Hz) was focused by a conical lens, and a column of laser-induced air plasmas (LIAP) came into being. The LIAP column, about 8 cm of long and 5 cm in maximal diameter, was studied by spectra measurement. The spectra of the LIAP column at different position were measured in the directions both perpendicular and parallel to the laser propagation respectively. From these data, the electron densities of the LIAP were evaluated. The experimental results indicate that the LIAP formed in an olivary shape, i. e. , symmetrical in the vertical direction but unsymmetrical in the horizontal direction, and the maximal electron density is about 10(18) cm(-3). The spatial distributions of atoms, molecules and ions in different states in the LIAP were also discussed, and provide clues for discovering the microstructure of LIAP.
ABSTRACT
The present paper reports the results of spectroscopic study on the oxygen plasma induced by a pulsed laser with a wavelength of 1.06 microm. The gas samples were pure oxygen (99.9999%) and the spectral range was from 300 to 900 nm. The temporal behavior of the spectra was measured. The experiment results showed that the spectra could be divided into continuous spectra and line spectra. Each component of the spectra attenuated according to the disparate mode along temporal development. The microcosmic physical processes and mechanisms were analyzed. The reason for the longer plasma spectral lifetime was discussed. These works were helpful to better understanding of the microscopic mechanisms during the decay of the laser-induced air plasmas, and also provide more experimental evidences for prolonging the decay time of plasmas in some technical applications.
ABSTRACT
The time-resolved spectra of the air-breakdown plasma produced by the 1.06 microns beam of a Nd:YAG laser were investigated by using the time-delayed spectra and the spectral line evolution methods. The time evolutions of the short wavelength band and long wavelength band of the continuous spectra of the air-breakdown plasma have been measured. The result shows that the decay rates of both bands are slowing down 0.5 microsecond after the excitation of the plasma, and the attachment and the detachment of free electrons by O2 in the plasma could be the reason for this behavior. The results of the time-resolved measurements of the line spectra show that most of the line spectra have the evolution time longer than their lifetimes, and the evolutions of some line spectra take a fashion of "decay-grow-decay". We consider these evolution behaviors of the line spectra to be related to various recombination processes and the energy transfer processes of the decaying plasma.
