[Progress in leaf area index retrieval based on hyperspectral remote sensing and retrieval models].

The leaf area index (LAI) is a very important parameter affecting land-atmosphere exchanges in land-surface processes; LAI is one of the basic feature parameters of canopy structure, and one of the most important biophysical parameters for modeling ecosystem processes such as carbon and water fluxes. Remote sensing provides the only feasible option for mapping LAI continuously over landscapes, but existing methodologies have significant limitations. To detect LAI accurately and quickly is one of tasks in the ecological and agricultural crop yield estimation study, etc. Emerging hyperspectral remote sensing sensor and techniques can complement existing ground-based measurement of LAI. Spatially explicit measurements of LAI extracted from hyperspectral remotely sensed data are component necessary for simulation of ecological variables and processes. This paper firstly summarized LAI retrieval method based on different level hyperspectral remote sensing platform (i. e., airborne, satelliteborne and ground-based); and secondly different kinds of retrieval model were summed up both at home and abroad in recent years by using hyperspectral remote sensing data; and finally the direction of future development of LAI remote sensing inversion was analyzed.

Twelve cases of the pectoralis major muscle tendon rupture with surgical treatment-an average of 6.7-year follow-up.

BACKGROUND: Pectoralis major tendon rupture is a relatively rare injury leading to both functional and cosmetic deficiency. The peak torque of the pectoralis major is significantly decreased after conservational treatment of a total rupture. We suppose that surgical intervention is better choice. METHODS: We retrospectively evaluated 12 patients who were diagnosed with distal pectoralis major muscle rupture and underwent operation in our institute from 1993 to 2007. All patients were male with a mean age of 32 (19 - 54) years. In 4 patients, tendon reconstruction was accomplished by fixing the tendon to the humerus using sutures passed through predrilled humeral bone tunnels. In 8 patients, tendon reconstruction was accomplished by directly suturing the muscle to the tendon. All patients followed an accelerated rehabilitation protocol. Treatment results were evaluated according to the following criteria: (1) visual analogue pain scale, (2) isokinetic strength measurements, (3) range of motion of shoulder joint, (4) cosmetic result, and (5) postoperative sports activity performance. In this study, we aimed to describe our surgical technique of reconstruction of the rupture of pectoralis major muscle and to summarize the clinical results of the operative treatment. RESULTS: At the final follow-up examination (6.5 years postoperatively), only nine patients were available for evaluation. Three of them had excellent results, and five had good results, while one had poor results. Eight of the patients were able to return to their preinjury level of sporting activity. In summary, 89% of the patients achieved excellent or good results. CONCLUSION: Surgical treatment by anatomic tendon repair and accelerated rehabilitation can make recovery of strength and function of the pectoralis major muscle.

Medial plica after reconstruction of anterior cruciate ligament.

BACKGROUND: The medial plica may be caused by direct trauma or joint degeneration, which also could be iatrogenic. There have been few reports in the literature discussing incidence of the medial plica caused by an operation on the knee joint, specifically after the reconstruction of anterior cruciate ligament (ACL). In this study, we aimed to evaluate and analyze the relationship between the incidence of the medial plica and reconstruction of the ACL. METHODS: A retrospective case series study was conducted to review the findings of 1085 patients between 2003 and 2007, who underwent second-look arthroscopy after reconstruction of the ACL (between 2002 and 2006). The correlation of the incidence of medial plica with the stability of the knee joint, the time from onset of injury to reconstruction surgery, the associated injuries, and the rate of progress during postoperative rehabilitation were analyzed. RESULTS: We found that 722 patients had the structure of a medial plica. The incidence after reconstruction of the anterior cruciate ligament (66.5%) was significantly higher than usually reported. All these medial plica had avascular fibrotic and thickened edges. An excision of pathologic medial plica and fat pad synovial fringes were done. The incidences were significantly different between the two groups with their reconstruction operation time, from onset of injury to surgery (less than one month or over 2 years), and the progress rate of postoperative rehabilitation (knee flexion could not be over 90 degrees in four weeks). The incidence was not different between the groups with knee stable conditions. CONCLUSIONS: Medial plica is more common in patients after reconstruction of ACL. More associated injuries and more rehabilitation difficulties can increase the medial plica incidence.

Effects of Ce on the short-term biocompatibility of Ti-Fe-Mo-Mn-Nb-Zr alloy for dental materials.

Effects of Ce on the short-term biocompatibility of Ti-Fe-Mo-Mn-Nb-Zr alloy designed for implant materials were studied by acute toxicity test, hemolytic test, and MTT assay. The elements and their concentration in surface films and extraction media of Ti alloys were investigated with XPS and ICP, respectively. The primary compositions of the surface films of Ti alloys with 0.3% Ce and without Ce were TiO2 and Nb2O5. There were 0.2 mg/l Fe and 0.16 mg/l Mn in the extraction medium of Ti alloy without Ce, while 0.27 mg/l Fe and 0.87 mg/l Mn in the extraction medium of Ti alloy with 0.3% Ce. The concentrations of Fe and Mn in the medium were too low to have any significant effects on human health. There was no sign of cytotoxicity in these tests. The cytotoxicity levels of Ti alloys without Ce and with 0.3% Ce were graded 0 and 1, respectively. The hemolytic degrees of Ti alloys without Ce and with 0.3% Ce were 0.558% and 0.67%, respectively. The cells being incubated in the extraction medium were normal. These phenomena indicated that Ce was innocuous within the concentration range of this study. In addition, the hemolytic ratio and toxicity level of Ti alloy with 0.3% Ce were a little higher than that of Ti alloy without Ce. This meant that Ce would slightly increase the toxicity of Ti alloy.