Objective To investigate and analyze the military operation ability and influence factors of soldiers alongthe border in an extremely cold environment and to provide a scientific basis for effectively improving the combat effective -ness of the army stationed the cold regions.Methods According to relevant standards, recruits(the length of service <1month) and old soldiers(the length of service >1 year) were randomly selected to investigate their military operationfactors, physical condition, sleep condition, mental health and cognitive ability.Results Cold was the main factor whichaffected military operation capability in cold regions.According to physical standards,border troops were in poor physicalcondition.Results of SCL-90 showed that the total score, the number of positive items , the score of each factor of the 130recruits were significantly lower than those of the Chinese army model and 46 veterans (P <0.05).There was nosignificant difference in these aspects between the 46 veterans and Chinese army model.Recruits were in better sleepcondition and had better instantaneous memory(P <0.05).Birthplace had no effect on these factors .Recruits from Centraland South China were in poorer sleep condition than those from cold regions (P <0.05).Results of SCL-90 showed that thetotal score,the factors of somatization, coercion, depression and anxiety of communication veterans were significantly higherthan those of the Chinese army model (P <0.05).The sleep condition of communication veterans was poorer than that ofmotorized infantry and patrol veterans (P <0.05).Conclusion Cold is the main factorthat impacts the ability of militaryoperations in cold regions.The physical work capacity of border guards in cold regions was significantly below the militarystandard, so the level of military training should be strengthened .Research on cold-protection equipment for special tasks should be strengthened.

Objective To evaluate the application value of three-dimensional speckle tracking imaging (3D-STI) in quantitatively evaluating the left ventricular global strain in recipients within 3 months after renal transplantation. Methods Clinical data including blood pressure, serum creatinine and tacrolimus blood concentration of 34 renal transplant recipients were collected before operation, 7 d, 1 month and 3 months after operation, respectively. Meanwhile, conventional echocardiography and 3D-STI examination were performed. Echocardiographic parameters [left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF)] and 3D-STI parameters [left ventricular global peak longitudinal strain (GPLS), global peak circumferential strain (GPCS), global peak radial strain (GPRS) and global peak area strain (GPAS)] of recipients were collected. The changes of these parameters before operation, 7 d, 1 month and 3 months after operation were statistically compared. The changing characteristic and application value of 3D-STI in quantitatively evaluating the left ventricular global strain in recipients within 3 months after renal transplantation were evaluated. Results LVEF and GPCS did not significantly differ at different time points (all P > 0.05), whereas LVEDV, LVESV, GPLS, GPAS and GPRS significantly differed at different time points from preoperative to within postoperative 3 months (all P < 0.001). GPLS, GPAS and GPRS trended to decline within postoperative 1 month, and slightly increased at 3 months after operation, which was still lower than the preoperative levels. Conclusions Application of 3D-STI may sensitively detect the changes of left ventricular global strain in recipients after renal transplantation when no significant variations are observed in postoperative LVEF. Compared with conventional echocardiography, 3D-STI may more accurately evaluate the changes of left ventricular global strain in recipients after renal transplantation.