Through a prospective randomized comparative study, treatment of flail chest by a non-surgical method of packing, strapping, and mechanical ventilation vs. surgical fixation were compared. After management, stability of the chest wall occurred in 85% of the patients in the surgical group. Forty-five percent of patients in this group required ventilatory support after fixation for an average of 2 days. Whereas in the conservative group, stability occurred in 50% of their patients, and 35% of patients required ventilatory support for an average of 12 days. Chest wall deformity in the form of stove-in chest and crowding of ribs was still obvious in 9 patients among the conservatively treated group, compared to only one patient who developed chest wall deformity in the surgically treated group. The pulmonary functions tested two months after management indicated that in the surgical group the patients had a significantly less restrictive pattern. Thus, surgical fixation of a flail segment is a method of great value in the treatment of flail chest, in which stability is achieved without deformity of the chest wall and patients have less restrictive impairment of pulmonary functions.

Gas sensors are important in many fields such as environmental monitoring, agricultural production, public safety, and medical diagnostics. Herein, tamm plasmon resonance in a photonic bandgap is used to develop an optical gas sensor with high performance. the structure of the proposed sensor comprises a gas cavity sandwiched between a one-dimensional porous silicon photonic crystal and an Ag layer deposited on a prism. the optimised structure of the proposed sensor achieves ultra-high sensitivity (S = 1.9×10 5 nm/RiU) and a low detection limit (DL = 1.4×10 −7 RiU) compared to the existing gas sensor. the brilliant sensing performance and simple design of the proposed structure make our device highly suitable for use as a sensor in a variety of biomedical and industrial applications. Gas sensing has different applications in many fields such as the food industry, medicine, safety, environment, agriculture, and cosmetic 1,2. For example, the detection of volatile organic compounds such as acetone and toluene in exhaled breath is used as a biomarker for many diseases 3,4. In addition, the determination of the concentration of harmful gases such as CO 2 and N 2 O can be applied as an environmental pollution monitor 5. Currently, optical gas sensors are of great interest to researchers because they do not require complicated radioactive/fluorescent labels 6,7. Surface plasmon resonance, Tamm plasmon (TP) resonance, waveguide, and photonic crystal are all examples of platforms for optical sensing 8-12. Photonic crystals (PCs) are useful for a wide range of biomedical and environmental sensing applications. This is due to an impressive set of relevant properties, such as ultrahigh sensitivity, low detection limit, and fast response time 13,14. PC refers to a range of materials characterised by a periodic refractive index along one, two, or three dimensions (1DPC, 2DPC, or 3DPC, respectively). The propagation of electromagnetic waves in PCs can be controlled because of the photonic bandgap (PBG) 15-17. 1DPCs are more appropriate for most applications, given their low cost and ease of fabrication compared to 2DPCs and 3DPCs 18. Recently, PCs have been widely used in various sensor systems. A high-precision gas index sensor, which was proposed by Jágerská et al., reached a sensitivity of 510 nm/RIU based on a PC air-slot cavity 19. Hua-Jun studied a surface plasmon resonance nanocavity antenna array for use as a gas sensor with a high sensitivity of 3200 nm/RIU 20. Wang et al. suggested a guided-mode resonance gas sensor with a sensitivity as high as 748 nm/ RIU 21. Pevec and Donlagic designed a fiber-optic Fabry-Perot gas sensor with a sensitivity of 1550 nm/RIU 22. García-Rupérez et al. presented a highly sensitive device for antibody detection using the slow light regime of a PC waveguide 23. Chen et al. designed a PC/Ag/graphene structure to function as a refractive index sensor based on the Tamm state, with a numerical sensitivity of 1178.6 nm/RIU 24. Auguié et al. studied TP resonance at the interface between a meta...

Photonic sensing is a novel technology and accurate measurement for biosensing applications. The present work proposes a defective one-dimensional photonic crystal (1D-PC) based on Si/SiO2-layers with a central liquid-filled defect layer as a blood sugar concentration biosensor in the visible region. The transmission spectrum is calculated numerically by using the transfer matrix method. The thickness of the defect layer and incident angle are optimized to achieve the best performance of the sensor. The results show that the localization of defect mode shifts to a longer wavelength with increasing the defect layer thickness. In addition to increasing the incident angle from θ0 = 0° to θ0 = 90°, the defect peak was shifted towards the short wavelength region. The optimized value of our structure demonstrates high sensitivity for the blood sugar (S = 1100 nm/RIU) in the range of concentration 0–500 mg dl−1, more enhancement of the quality factor (3.539 × 106) and very low limit of detection (8.8 × 10−9 RIU) are achieved. Our results indicate that the proposed structure has higher performance as a blood sugar sensor than many previously reported data. Besides, the simplicity of the proposed structure makes it favorable to the industrial design using inexpensive and massive product nanofabrication techniques.

In the framework of the Glauber multiple scattering theory, the complete expansion ͑which contains 2 AϫB Ϫ1 terms͒ of the Glauber amplitude of elastic scattering between two nuclei A, Bу4 is obtained. Using double Gaussian density consistent with the electron-scattering experiments, the differential cross section (nuclearϩCoulomb) is calculated and compared with the experimental data. It is shown that, in general, higher order terms give a substantial improvement in comparison with the previous optical limit results at relatively large scattering angles. The effect of invoking a phase-variation in the nucleon-nucleon ͑NN͒ amplitude is examined. We found that the presence of the phase variation improves our results, especially at the minima of the diffraction pattern.