Blast injuries with contrasting outcomes treated by military surgery strategies: A case report.

The treatment strategy for blast injuries is closely linked to the clinical outcome of blast injury casualties. However, the application of military surgery experience to blast injuries caused by production safety accidents is relatively uncommon. In this study, the authors present 2 cases of blast injuries caused by one gas explosion, both cases involved individuals of the same age and gender and experienced similar degree of injury. The authors highlight the importance of using a military surgery treatment strategy, specifically emphasizing the need to understand the concept of damage control and disposal. It is recommended that relevant training in this area should be strengthened to improve the clinical treatment of such injuries. This study provides a valuable reference for healthcare professionals dealing with blast injuries.

Effect of early enteral nutrition on outcomes of trauma patients requiring intensive care.

PURPOSE: To investigate the effect of early enteral nutrition on outcomes of trauma patients in the intensive care unit (ICU). METHODS: Clinical data of trauma patients in the ICU of Daping Hospital, China from January 2012 to December 2017 was retrospectively analyzed, including patient age, gender, injury mechanism, injury severity score (ISS), nutritional treatment, postoperative complications (wound infection, abdominal abscess, anastomotic rupture, pneumonia), mortality, and adverse events (nausea, vomiting, abdominal distention). Only adult trauma patients who developed bloodstream infection after surgery for damage control were included. Patients were divided into early enteral nutrition group (<48 h) and delayed enteral nutrition group (control group, >48 h). Data of all trauma patients were collected by the same investigator. Data were expressed as frequency (percentage), mean ± standard deviation (normal distribution), or median (Q1, Q3) (non-normal distribution) and analyzed by Chi-square test, Student's t-test, or rank-sum test accordingly. Multiple logistic regression analysis was further adopted to investigate the significant variables with enteral nutrition. RESULTS: Altogether 876 patients were assessed and 110 were eligible for this study, including 93 males and 17 females, with the mean age of (50.0 ± 15.4) years. Traffic accidents (46 cases, 41.8%) and fall from height (31 cases, 28.2%) were the dominant injury mechanism. There were 68 cases in the early enteral nutrition group and 42 cases in the control group. Comparison of general variables between early enteral nutrition group and control group revealed significant difference regarding surgeries of enterectomy (1.5% vs. 19.0%, p = 0.01), ileum/transverse colon/sigmoid colostomy (4.4% vs. 16.3%, p = 0.01) and operation time (h) (3.2 (1.9, 6.1) vs. 4.2 (1.8, 8.8), p = 0.02). Other variables like ISS (p = 0.31), acute physiology and chronic health evaluation≥20 (p = 0.79), etc. had no obvious difference. Chi-square test showed a much better result in early enteral nutrition group than in control group regarding morality (0 vs. 11.9%, p = 0.03), length of hospital stay (days) (76.8 ± 41.4 vs. 81.4 ± 44.7, p = 0.01) and wound infection (10.3% vs. 26.2%, p = 0.03). Logistic regression analysis showed that the incidence of wound infection was related to the duration required to achieve the enteral nutrition standard (OR = 1.095, p = 0.002). Seventy-six patients (69.1%) achieved the nutritional goal within a week and 105 patients (95.5%) in the end. Trauma patients unable to reach the enteral nutrition target within one week were often combined with abdominal infection, peritonitis, bowel resection, intestinal necrosis, intestinal fistula, or septic shock. CONCLUSION: Early enteral nutrition for trauma patients in the ICU is correlated with less wound infection, lower mortality, and shorter hospital stay.

[Chromatism Analysis of Multispectral Imaging System Based on AOTF and Hardware Compensation Strategy].

In view of the existing chromatism in the AOTF multispectral imaging system causes different wavelength imaging clarity under different focal length , even under the fixed wavelength, due to the horizontal direction (diffraction) spectral broadening, which leads to clear horizontal lines and blurring vertical lines. This paper made a concrete analysis of the chromatism of AOTF, pointing out the causes of imaging blurring. According to the imaging characteristics of AOTF multispectral imaging system, this paper proposed an improved algorithm based on SSIM, which can be used to evaluate the image sharpness. The target of the original algorithm was two images (one as a reference image, the other one as the test image), while the algorithm proposed in this paper made similarity analysis between the adjacent lines in one target image, small similarity in change edges declares great contrast, thus the image is clearer. The image quality caused by chromatism in the AOTF multispectral imaging system can be compensated by automatic focusing system, which mainly based on this algorithm. It has small calculated amount and fast speed. The feasibility and practicability of the compensation strategy were verified through experiments. The results show that this strategy can effectively solve the image blurring caused by chromatism in the AOTF multispectral imaging system, which has an important application value.

[The Research of Spectral Polarization Imaging Detection System Based Dual-AOTFs].

Acousto-optic tunable filter (AOTF) has the advantages of small size, good stability, wide range of wavelength scanning, quick modulation speed and so on. So AOTF is widely used in spectral imaging. But the detection of spectral polarization imaging is seldom found by using AOTF individually., Anew method of spectral polarization imaging based on dual-AOTFs is proposed. This method shows that the incident light is firstly divided into two beams by splitting mirror, and then two beams of light are through two AOTFs respectively, and the polarization direction of +1 diffraction order formed by AOTF is at a 45° against the other. The intensity of 0°, 45°, 90°and 135° can be obtained by ±1 diffraction orders of dual-AOTFs. Finally, the Stokes parameters are obtained by ±1 diffraction orders imaging of dual-AOTFs. They are S0 (the sum of light intensity between 0° and 90°), S1(the difference of light intensity between 0° and 90°) and S2 (the difference of light intensity between 45° and 135°). The target degree of linear polarization (DoLP) and angle of linear polarization (AoLP) is realized by corresponding theoretical formula. Furthermore, the polarization imaging of different wavelengths is realized with frequency sweep of dual-AOTFs so as to ultimately detect the spectral polarization imaging. The experiment has been verified through polarization imaging of three different lights, such as λ=500 nm, λ=550 nm and λ=600 nm.

[The Study of Large OPD's PEM Based on Micro Trapezoidal Photo-Elastic Crystals].

Existing Photoelastic Modulator (PEM), whose optical path difference (OPD) is small, has strict requirements on the incident spot size and is poor in the aspect of light use efficiency under multiple reflections. What's more, Photoelastic Modulator based Fourier transform spectrometer (PEM-FTS) spectral resolution is relatively poor. Because there are these disadvantages in the PEM, this paper presents a method of large optical path difference whose PEM is based on micro trapezoidal photoelastic crystals. By improving the structure of photoelastic crystal, the PEM becomes micro trapezoidal octagonal structure. And two transmission surfaces are changed slightly into a certain angle. Therefore, the PEM improved can not only increase the optical path difference of the PEM, but also have less requirements on the incident spot size. Firstly, a detailed analysis of the maximum modulation optical path difference was made in this paper. Secondly, the equation of maximum optical path difference was deduced under any angle and any position of incident light, vibration displacement and stress distribution of PEM are analyzed by the way of COMSOL Multiphysics 4.3a. Again, a method was analyzed to find the best angle of incidence, combining with maximum optical path difference and energy efficiency. Then the large OP's PEM is designed and processed, including two parts: photoelastic crystal and piezoelectric crystal. Moreover, ZnSe crystal is used as photoelastic crystal, and piezoelectric quartz crystal is used as piezoelectric crystal. With experiment analyzed by 632. 8 nm He-Ne laser, the results show that under the same driving voltage, the optical path difference of the PEM improved is about 19. 25 times bigger than the normal PEM, and the relative error is 1.3%.

[A New Strategy of Spectrum and Polarization Measuring based on LCVR and AOTF].

In view of the existing relatively cumbersome polarization measurement method of using liquid crystal phase variable retarder (LCVR) and acousto-optic tunable filter (AOTF), a new strategy of spectrum and polarization measurement is put forward. This method removed mechanical movement and reduced the amount of phase delay from four groups to two groups. This method realizes the spectrum and polarization measurements by measuring the plus and minus 1 level diffraction light of the system with two LCVR, one AOTF and two same version detectors. For the polarization measurement of a particular wavelength, the computer controlled LCVR driving voltage to achieve the required phase delay in accordance with the requirements of the wavelength, it also controlled the driving frequency to implement the required wavelength selection of AOTF. Because of the different driving frequencies of AOTF corresponding to the different wavelengths, so it can get the spectral information by scanning the whole frequency bands, In this paper detailed principles are deduced and the polarization model of AOTF is analyzed, it also deduced the measurement formula of I, Q, U in the corresponding Stokes parameter through the theoretical calculation Muller matrix of the LCVR and AOTF. Finally it analyzed and simulated the measurement error of the whole system which was caused by the tiny deviation of phase delay, the simulation results show that relative error <3% when the phase delay amount within the range of ±π/100. This experiment proved the feasibility and accuracy of the measurement system, the results show that the error of the measuring system overall <6%. This study provides a new method of polarization measurement which is simple, feasible and precise, it has important application value.

[Research on the neas infrared focal plane array detector imaging technology used in the laser warning].

In order to achieve the incoming laser's accurate position, it is necessary to improve the detected laser's direction resolution. The InGaAs focal plane array detector with the type of FPA-320 x 256-C was selected as the core component of the diffraction grating laser warning device. The detection theory of laser wavelength and direction based on diffraction grating was introduced. The drive circuit was designed through the analysis of the detector's performance and parameters. Under the FPGA' s timing control, the detector's analog output was sampled by the high-speed AD. The data was cached to FPGA's extended SRAM, and then transferred to a PC through USB. Labview on a PC collects the raw data for processing and displaying. The imaging experiments were completed with the above method. With the wavelength of 1550 nm and 980 nm laser from different directions the diffraction images were detected. Through analysis the location of the zero order and one order can be determined. According to the grating diffraction theory, the wavelength and the direction of the two-dimensional angle can be calculated. It indicates that the wavelength error is less than 10 nm, and the angle error is less than 1 degrees.

[Research of dual-photoelastic-modulator-based beat frequency modulation and Fourier-Bessel transform imaging spectrometer].

As the existing photoelastic-modulator(PEM) modulating frequency in the tens of kHz to hundreds of kHz between, leading to frequency of modulated interference signal is higher, so ordinary array detector cannot effectively caprure interference signal..A new beat frequency modulation method based on dual-photoelastic-modulator (Dual-PEM) and Fourier-Bessel transform is proposed as an key component of dual-photoelastic-modulator-based imaging spectrometer (Dual-PEM-IS) combined with charge coupled device (CCD). The dual-PEM are operated as an electro-optic circular retardance modulator, Operating the PEMs at slightly different resonant frequencies w1 and w2 respectively, generates a differential signal at a much lower heterodyne frequency that modulates the incident light. This method not only retains the advantages of the existing PEM, but also the frequency of modulated photocurrent decreased by 2-3 orders of magnitude (10-500 Hz) and can be detected by common array detector, and the incident light spectra can be obtained by Fourier-Bessel transform of low frequency component in the modulated signal. The method makes the PEM has the dual capability of imaging and spectral measurement. The basic principle is introduced, the basic equations is derived, and the feasibility is verified through the corresponding numerical simulation and experiment. This method has' potential applications in imaging spectrometer technology, and analysis of the effect of deviation of the optical path difference. This work provides the necessary theoretical basis for remote sensing of new Dual-PEM-IS and for engineering implementation of spectra inversion.

[Evaluation of green tangerine peel processed with vinegar using HPLC fingerprint technique].

OBJECTIVE: To develop an HPLC method for determination of fingerprints and evaluate green tangerine peel (GTP) processed with vinegar. METHOD: The samples were extracted with 50% ethanol using ultrasonic bath and analyzed on a Chromasil C18 column eluted with methanol and water containing 0.2% acetic acid in a linear gradient program. The flow rate was 1.0 mL x min(-1), and detection wavelength was set at 280 nm. RESULT: The RSD values of relative retention times and peak areas of main peaks were all less than 5%. The fingerprints of Geqingpi and Sihuaqingpi were different. The fingerprints of the processed and the unprocessed were almost same, and the fingerprint differences among the different batches processed with the same technology from the same unprocessed GTP were not obvious. CONCLUSION: The influence of processing with vinegar on 50% ethanol extracts were not evident, and the technological pross was stable. It was found that the fingerprints of Geqingpi and Sihuaqingpi were different, but it should be study further.