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Objective@#To compare the effect of two different methods of "3-PR" participatory health education and traditional distribution of publicity materials on health literacy improvement of medical students, to provide a reference for making more effective measure to improve health literacy.@*Methods@#173 Second-grade students in nursing major were selected in a secondary vocational school in Datong City. Two different intervention methods were used to intervene for 8 weeks. The experimental group (92 students) received "3-PR" participatory health education; the traditional health education intervention in the control group(81 students). The "National Residents’ Health Literacy Monitoring Questionnaire 2015" was used to conduct a questionnaire survey on the experimental group and the control group before and after the intervention, and to compare the effects before and after the intervention.@*Results@#The average score of health literacy was (36.04±9.43) points and (36.01±10.17) points before and after intervention in the control group; (35.78±8.91) points and (49.53±13.53) points before and after intervention in the experimental group; No statistical difference between experimental and control group was found before intervention(t=0.18, P=0.86); There was no significant difference in health literacy score before and after intervention for the control group(t=0.03, P=0.98); Health literacy significantly increased in the experimental group after intervention(t=-11.36, P=0.00). Adequate health literacy accounted for 3.70% and 4.94% before and after intervention in the control group and 4.35% and 45.65% in the experimental group before and after intervention. No significant difference was found in adequate health literacy proportion between the two groups before intervention(χ2=0.00, P=1.00). However, the difference showed statistically significant after intervention(χ2=36.58, P=0.00). The change of health literacy score in the control group and the experimental group was (-0.02±7.52) and (12.75±10.77), respectively, accounting for 1.24% decrement and 41.30% increment. The difference between the two groups was statistically significant (t=-8.93, P=0.00). The dimension-and type-specific score of health literacy showed similar pattern.@*Conclusion@#The "3-PR" participatory health education model is more effective than the traditional health education method in improving health literacy, and it could be carried out by multi-disciplinary students.
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In this paper, a laterally coupled distributed feedback (LC-DFB) laser based on modulation p-doped multiple InAs/GaAs quantum dot (QD) structures has been fabricated. The device exhibits a high side-mode suppression ratio (SMSR) of > 47 dB and a high thermal stability of dλ/dT = 0.092 nm/K under continuous-wave (CW) operation, which is mainly attributed to the high material gain prepared by modulation p-doping and rapid thermal annealing (RTA) process, and the significantly reduced waveguide losses by shallow-etched gratings and its close proximity to the laser ridge feature in the LC-DFB laser. With this superior performance of the DFB laser, the wide tunable dual-wavelength lasing operation has been obtained by delicately defining different periods for the grating structures on the two sides of the laser ridge or combining the reduced laser cavity length. The wavelength spacing between the two lasing modes can be flexibly tuned in a very wide range from 0.5 to 73.4 nm, corresponding to the frequency difference from 0.10 to 14 THz, which is the largest tuning range by the utilization of single device and hence providing a new opportunity towards the generation of CW THz radiation.
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Semiconductor broadband light emitters have emerged as ideal and vital light sources for a range of biomedical sensing/imaging applications, especially for optical coherence tomography systems. Although near-infrared broadband light emitters have found increasingly wide utilization in these imaging applications, the requirement to simultaneously achieve both a high spectral bandwidth and output power is still challenging for such devices. Owing to the relatively weak amplified spontaneous emission, as a consequence of the very short non-radiative carrier lifetime of the inter-subband transitions in quantum cascade structures, it is even more challenging to obtain desirable mid-infrared broadband light emitters. There have been great efforts in the past 20 years to pursue high-efficiency broadband optical gain and very low reflectivity in waveguide structures, which are two key factors determining the performance of broadband light emitters. Here we describe the realization of a high continuous wave light power of >20 mW and broadband width of >130 nm with near-infrared broadband light emitters and the first mid-infrared broadband light emitters operating under continuous wave mode at room temperature by employing a modulation p-doped InGaAs/GaAs quantum dot active region with a 'J'-shape ridge waveguide structure and a quantum cascade active region with a dual-end analogous monolithic integrated tapered waveguide structure, respectively. This work is of great importance to improve the performance of existing near-infrared optical coherence tomography systems and describes a major advance toward reliable and cost-effective mid-infrared imaging and sensing systems, which do not presently exist due to the lack of appropriate low-coherence mid-infrared semiconductor broadband light sources.
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In this paper, we demonstrated the fabrication of one-dimensional (1D) and two-dimensional (2D) periodic nanostructures on III-V GaAs substrates utilizing laser direct writing (LDW) technique. Metal thin films (Ti) and phase change materials (Ge2Sb2Te5 (GST) and Ge2Sb1.8Bi0.2Te5 (GSBT)) were chosen as photoresists to achieve small feature sizes of semiconductor nanostructures. A minimum feature size of about 50 nm about a quarter of the optical diffraction limit was obtained on the photoresists, and 1D III-V semiconductor nanolines with a minimum width of 150 nm were successfully acquired on the GaAs substrate which was smaller than the best results acquired on Si substrate ever reported. 2D nanosquare holes were fabricated as well by using Ti thin film as the photoresist, with a side width of about 200 nm, but the square holes changed to a rectangle shape when GST or GSBT was employed as the photoresist, which mainly resulted from the interaction of two cross-temperature fields induced by two scanning laser beams. The interacting mechanism of different photoresists in preparing periodic nanostructures with the LDW technique was discussed in detail.
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Transition-metal dichalcogenides (TMDs) nanostructures including nanotubes and monolayers have attracted great interests in materials science, chemistry to condensed matter physics. We present an interesting study of the vibration modes in multi-walled tungsten sulfide (WS2) nanotubes prepared via sulfurizing tungsten oxide (WO3) nanowires which are investigated by confocal micro-Raman spectroscopy. The inter-layer vibration mode of WS2 nanotubes, A1g, is found to be sensitive to the diameter and curvature strain, while the in-plane vibration mode, E(1)2g, is not. A1g mode frequency shows a redshift by 2.5 cm(-1) for the multi-layered nanotubes with small outer-diameters, which is an outcome of the competition between the Van der Waals force stiffening and the curvature strain softening. We also show that the Raman peak intensity ratio is significantly different between the 1-2 wall layered nanotubes and monolayer flat sheets.