ABSTRACT
OBJECTIVE: To observe the effect of gasless endoscopic thyroidectomy through an axillary approach (GETAN) on the recurrent laryngeal nerve in patients with thyroid cancer. METHODS: One hundred and ten patients with thyroid cancer admitted to the department of general surgery, the First Affiliated Hospital of Xiamen University were retrospectively selected as the research subjects. They were divided into an observation group (OG, 55 patients, treated with GETAN) and a control group (CG, 55 patients, treated with conventional radical resection for papillary thyroid cancer). Clinical indicators, pain degree, negative emotions, recurrent laryngeal nerve injury, vocal and swallowing function, and the incidence of complications were compared between the two groups. RESULTS: In terms of clinical indicators, the operation time, intraoperative blood loss, extubation time, and hospitalization time in the OG were shorter than those of the CG (all P<0.05). The scores of Visual Analogue Scale (VAS) at one, two, and three days after surgery in the OG were lower than those in the CG (all P<0.001). As for the negative emotions, the Self-Rating Anxiety Scale score, and Self-Rating Depression Scale score in the OG were lower than those in the CG (both P<0.001). The incidence of postoperative recurrent laryngeal nerve injury in the OG was lower than that of the CG (P<0.001). Another analysis showed that GETAN was a protective factor against recurrent laryngeal nerve injury in patients with thyroid cancer (P<0.05). The Voice Handicap Index and Swallowing impairment score one week and one month after surgery were lower in the OG than in the CG (all P<0.001). The incidence of postoperative complications such as hypocalcemia, wound infection, and numbness of hands and feet in the OG was lower than that in the CG (all P<0.001). CONCLUSION: The GETAN approach is able to relieve postoperative pain, anxiety, and depression; reduce the laryngeal recurrent nerve injury; promote the recovery of laryngeal recurrent nerve; and decrease the incidence of vocal and swallowing dysfunction It is worthy of clinical promotion.
ABSTRACT
Recent studies have shown that microporous graphene foam (GF) exhibits photoacoustic effect when irradiated with modulated light. Inspired by this phenomenon, we fabricated a light emitting diode (LED)-induced system-level GF speaker that generates photoacoustic waves in a frequency range of 0.2-16 kHz or plays music with high fidelity when illuminated by modulated LED light. LED light modulation is realized by our specially designed driving circuit that combines the AC voltage corresponding to the audio signal (sinusoidal signal or music from a cell phone) and a DC bias. To reveal the effect of the microporous structure of GF on the photoacoustics, we simulated the thermo-acoustic process (the second process of the photoacoustic effect). We built a periodically heated model of micro-spherical air unit with a diameter of 42 µm to investigate the relationship between the heat flow absorbed by the air unit and the thermo-acoustic wave created by it. The simulated results show that in the frequency range of 0.2-16 kHz, the thermo-acoustic pressure correlates with the frequency of heat flow. Moreover, in the diameter range of 10 to 80 µm of the air unit, the thermo-acoustic pressure is directly proportional to the square of the diameter of the air unit, suggesting that the photoacoustic effect can be enhanced by increasing the size of the GF pores to a certain extent. This work demonstrates the light-induced speakers and provides theoretical support for the photoacoustic effect that occurs in materials with microporous structures.
ABSTRACT
An uncooled infrared focal plane array (FPA) for a multiband optical imaging system monitoring small gas leakages is low in cost but limited by its frame rate and sensitivity. We propose the concept of Archimedean spiral push-broom filtering (ASPBF), where the trajectory of an Archimedean spiral over the FPA is approximated as a straight line. The ASPBF precisely matches the electronic pulse scanning of the uncooled infrared FPA row by row to improve the frame rate. We applied differential imaging to promote gas detection sensitivity. Prototype can detect 11 ml/min of ethylene gas at ΔT = 3 °C with frame rate of 8 fps.
