Spatially resolved temperature measurement in the carbon dioxide arc under different gas pressures.

Carbon dioxide (CO2) is a promising alternative to sulfur hexafluoride for high-voltage circuit breaker applications. It is important to have a detailed understanding of CO2 arc properties. In this paper, radial temperature distribution of the free burning direct current arc in pure CO2 was investigated. Optical emission spectrometry was applied under different pressures (0.5 atm, 1 atm, and 1.5 atm) and at different axial positions (1 mm, 2 mm, 3 mm above the cathode). Assuming local thermodynamic equilibrium, the Fowler-Milne method was adopted for O I 715.67 nm and O I 777.19 nm in the periphery of the arc, and the single-line method was adopted for C II 657.81 nm near the center of the arc. Radial temperature profiles obtained by these two methods were combined at the position where normal temperature was assigned. The results indicate that near the center of the arc, higher pressure would lead to lower temperature; as the distance from the cathode to the position measured increases, the maximum temperature in the arc center would decrease. In addition, the temperature would decrease more sharply toward the periphery if the central temperature of the arc is higher.

[Excision of necrotic and infected tissues combined with induced membrane and external fixator technique for the treatment of chronic osteomyelitis in tibia after fracture operation].

OBJECTIVE: To investigate the clinical efficacy of excision of necrotic and infected tissues combined with induced membrane and external fixator technique to treat chronic osteomyelitis in tibia after fracture operation. METHODS: From June 2011 to June 2014, a total of 13 patients with tibia osteomyelitis were treated with excision of necrotic and infected tissues and external fixator technique in the first stage. There were 8 males and 5 females, ranging in age from 16 to 67 years old with an average of (37.3±14.3) years old. Within 6 to 8 weeks the induced membrane was formed and the induced membrane technique was applied to promote new bone forming in the second stage. RESULTS: Thirteen patients had no reinfection and achieved complete bone healing after 24 to 52 months follow-up. All the patients had satisfactory function. CONCLUSIONS: Excision of necrotic and infected tissues combined with induced membrane and external fixator technique to treat chronic osteomyelitis in tibia after fracture operation can provide satisfactory results.

RASSF7 expression and its regulatory roles on apoptosis in human intervertebral disc degeneration.

Apoptosis plays an important role in intervertebral disc degeneration (IDD). Overwhelming evidence indicates that RASSF7 is essential for cell growth and apoptosis. Recently, it has been noted that the JNK signaling can be negatively regulated by suppressing phosphorylated-MKK7 activation during pro-apoptosis. We aimed to investigate the RASSF7 expression level in human degenerative nucleus pulposus (NP) cells and non-degenerative NP cells and the link between RASSF7-JNK with NP cells apoptosis. We harvested NP tissues from 20 IDD patients as disease group and 8 cadaveric donors as normal controls. We detected RASSF7 expression by Real-time-PCR and western blotting. Consequently, we found that the expression of RASSF7 was higher in non-degenerative group than in degenerative group (P<0.05). Overexpression of RASSF7 in degenerative NP cells led to decreased apoptosis rate than that in scramble group (P<0.05). Collectively, our findings suggest that RASSF7 plays an important role in human IDD and RASSF7 might be potentially developed as a curative agent.

[Clinical contrast of percutaneous pinning with plaster splint and open reduction and pulling out wire in the treatment of mallet fingers].

OBJECTIVE: To compare differences in the clinical outcomes between percutaneous pinning with plaster splint and open reduction and pulling out wire in the treatment of mallet fingers. METHODS: From December 2002 to September 2007, 72 patients with mallet fingers were treated. They were divided into two groups: group A and group B. In group A, 38 patients were treated by open reduction and pulling out wire, 34 males and 4 females, aged (26.0 +/- 8.5) years. Among them, 2 patients were injured in the index finger, 11 in the middle finger, 18 in the ring finger and 7 in the little finger. Thirty-three patients suffered from sports injuries, 5 from falling wounds. The average time between the injury and the surgery was (6.1 +/- 3.1) days. In group B, 34 patients were treated by percutaneous pinning with plaster splint, 26 males and 8 females, aged (28.1 +/- 10.7) years. Among them, 1 patient was injured in the index finger, 9 in the middle finger, 15 in the ring finger and 9 in the little finger. Thirty-one patients suffered from sports injuries, 3 from falling wounds. The average time between the injury and the surgery was (6.3 +/- 3.6) days. All the fingers had typical mallet malformation, and X-ray films showed avulsed fractures of distal-segment phalanxes at the dorsal basilar part. RESULTS: The operation time was (61.8 +/- 12.8) minutes in group A and (7.0 +/- 2.6) minutes in group B. All patients in both groups were followed up for 6-24 months (11.9 months on average in group A and 13.2 months in group B). In group A, apart from 3 patients who had flap necrosis and infection, all the other patients obtained healing by first intention. One patient had palmar skin ulcer at 6 days after the operation and healed after proper treatment. Thirty-six patients gained bone union at (47.6 +/- 8.7) days postoperatively and 2 patients had pseudarthrosis, which improved after reconstruction of the extensor tendon attachment point. According to the total active movement (TAM) functional assessment system, 10 cases were excellent, 18 good, 8 fair and 2 poor, with the choiceness rate of 73.7%. In group B, all incisions obtained healing by first intention without pin-track infection, flap necrosis and migration of the pins and gained bone union at (27.7 +/- 3.9) days after the operation. According to the TAM functional assessment system, 19 cases were excellent, 13 good and 2 fair, with the choiceness rate of 94.1%. There were significant differences between the two groups in operation time, complications, healing time and choiceness rate (P < 0.05). CONCLUSION: Percutaneous pinning with plaster splint is simple in operation and has smaller incisions and fewer complications compared withopen reduction and pulling out wire, and proves to be a useful way in the treatment of mallet fingers.