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Historical version backup data query efficiency was dependent on the version chain length in a multi-version backup data storage system.A novel block-level backup data multi-version consolidation method was presented for this problem.Any version of a historical full system snapshot could be generated within the incremental backup data version sequence.Theoretical analysis showed that it could increase the target snapshot version query efficiency significantly in the version chain.A variable-length block version merging algorithm was presented to decrease the computing complex-ity in the process of snapshot version merging,according to the block-level backup data distribution features.Finally,the concrete applications and performance analysis for block-level version consolidation method was also introduced.The simulated experiments results expose that the version consolidation method can eliminate redundant version of backup data with the same version chain length,and it can increase full system recovery efficiency than traditional methods sig-nificantly.

HitIct, a Chinese corpus for the evaluation of lossless compression algorithms based on ANSI code, was proposed.In accordance with the principle of application representativeness, Complementary principle and openness principle, a large number of candidate files were obtained from the Internet, and then average compression ratio, average correlation coefficient, compression ratio correlation coefficient and standard deviation were used to select the files that give the most accurate indication of the overall performance of compression algorithms.Experimental results show that this collection has a good representativeness and stability, and can be used as the supplementary test set of the main benchmark for comparing compression methods.

A new model was proposed to maintain sequence and ownership of netflow.This model adopted weak se-quence-based high speed data structure in memory to improve real time storage ability.In the disc level a multi-level in-dex data netflow spanning tree was proposed to improve sequence and ownership retrieval efficiency.The performance of evaluation exposes that the storage model of netflow can improve real-time storage ability and decrease the quantities of index data dramatically.

In the complex and dynamic Grid system,failure of resources was very common.And the failure of Grid re-sources can halt the execution of tasks on them.To mitigate this problem,the concept of tasks survivability was pro-posed,a local objective function which can be adjusted was proposed by incorporating the makespan and survivability of tasks and maximizing the survivability of tasks was devised.The simulation results confirm that the scheduling algorithm can trade off these two objectives,and can satisfy different demand by adjusting the weight parameter in the objective function.So it can be applied in the complex Grid computing environment well.

Objective: To investigate the clinicopathological features of testicular malignant Leydig cell tumor (TMLCT) and improve the non-invasive diagnosis of the disease., Methods: We retrospectively analyzed the clinicopathological data on a case of TMLCT, detected the circulating tumor cells (CTC) in the peripheral venous blood, and reviewed the related literature., Results: The patient, a 47-year-old male, underwent radical orchidoepididymectomy under general anesthesia. Postoperative pathology confirmed the lesion to be TMLCT, which was mainly composed of Leydig cells and suspected with vessel carcinoma embolus. Immunohistochemistry showed the tumor cells to be positive for α-inhibin, Ki67, CD30, vimentin, EMA, and PLAP, but negative for CK, CK7, S100, CD10, SMA, Des, AFP, hCG, CEA, CK19, CD117, Oct-4, LCA, CD20, Pax-5, CD3, and CD43. Two CTCs were detected in the peripheral venous blood. The patient received 3 courses of chemotherapy for retroperitoneal multiple lymph nodes metastasis post-operatively. Subsequent CT imaging manifested no obvious reduction of the retroperitoneal lymph nodes and consequently the patient again underwent retroperitoneal lymphadenectomy and cryoablation. At 8 months after treatment, CT examination revealed notably enlarged retroperitoneal lymph nodes with the right adrenal gland evidently invaded., Conclusion: TMLCT is an extremely rare sex-gonad stromal tumor with high malignancy and poor prognosis, and CTCs may be used for its early diagnosis and prognostic prediction.

Objective: To form the strategy of prevention of postoperative pulmonary complication, investigate the incidence of early hypoxemia after general anesthesia for surgery in intensive care unit (ICU), and assess its impact on the prognosis of patients., Methods: Clinical data of patients who were directed transferred to ICU after general anesthesia for selective surgery during October 2011 to June 2012 were analyzed retrospectively. According to the oxygenation index (PaO2/FiO2) obtained in 1 hour after ICU admission, patients were divided into three groups, normal blood oxygen level (n=134, PaO2/FiO2>300 mm Hg, 1 mm Hg=0.133 kPa), mild hypoxia (n=88, PaO2/FiO2 200-300 mm Hg) and moderate to severe hypoxia (n=49, PaO2/FiO2≤200 mm Hg) groups. Duration of mechanical ventilation, ICU stay days, postoperative hospital stay days, and duration of oxygen therapy were compared among three groups., Results: Two hundred and seventy-one patients were included. There were no statistical differences in gender, age, duration of operation, type of operation, and postoperative extubation. The incidence rate of hypoxemia (PaO2/FiO2≤300 mm Hg) was 50.6%. Duration of mechanical ventilation was significantly prolonged in moderate to severe hypoxia group as compared with normal blood oxygen group [20.3 (13.0, 46.1) hours vs. 12.5 (6.0, 17.5) hours, D=40.803, P=0.005], the ratio of duration of mechanical ventilation longer than 24 hours was significantly higher in moderate to severe hypoxia group compared with normal blood oxygen and mild hypoxia groups (44.4% vs. 8.8%, 16.1%, χ(2)1=21.394, P2=0.000; χ(2)2=9.368, P2=0.002). The ICU stay was significantly longer in moderate to severe hypoxia group than normal blood oxygen and mild hypoxia groups [44.5 (21.5, 121.5) hours vs. 22.0 (18.0, 46.5) hours, 21.8 (19.0, 66.9) hours, D1=54.302, P1=0.000; D2=44.171, P2=0.005]. Compared with normal blood oxygen group, postoperative hospital stay days and duration of oxygen therapy were significantly longer in moderate to severe hypoxia group [postoperative length of stay: 15.0 (12.0, 21.5) days vs. 9.0 (12.0, 16.0) days, D=40.851, P=0.005; duration of oxygen therapy: 170.0 (97.5, 307.5) hours vs. 89.0 (47.8, 192.0) hours, D=45.049, P=0.002]., Conclusions: The incidence of hypoxemia postoperative patients after general anesthesia is high when transferred to ICU. PaO2/FiO2≤200 mm Hg was closely related to prolonged duration of mechanical ventilation, ICU stay days, postoperative hospital stay days, and duration of oxygen therapy.

With the development of the quantitative researches using ocean color remote sensing data sets, study on reducing the uncertainty of the response of the ocean color remote sensors to the polarization characteristics of the target has been attracting more and more attention recently. Taking MODIS as an example, the polarization distribution in the whole field of view was analyzed. For the atmosphere path radiance and the apparent radiance considering the coupling between ocean surface and atmosphere, the polarization distribution has a strong relation with the imaging geometry. Compared to the contribution of the polarization from the rough sea surface, the contribution from the atmosphere is dominated. Based on the polarization characteristics in the field of view, the influence of the polarization coupling error on the quality of the satellite data was studied with the assumption of different polarization sensitivities. It was found that errors due to polarization sensitivity in the field of view are lower than water leaving radiance only when the polarization sensitivity is less than 2%. And in this case it can meet the need of the retrieval of water leaving radiative products. The method of the compensation for the polarization coupling error due to the atmosphere is proposed, which proved to be effective to improve the utilization of satellite data and the accuracy of measured radiance by remote sensor.

Objective: To elucidate the relativity among three kinds of continuous hemodynamics monitoring techniques: thermodilution via Swan-Ganz catheter, pulse contour analysis method (PiCCO), partial CO(2) rebreathing method (non invasive cardiac output, NICO), in patients with mechanical ventilation., Methods: In 13 patients with respiratory failure due to different causes, hemodynamics were continuously monitored with Swan-Ganz catheterization, PiCCO, NICO simultaneously. The therapeutic measures and the type of ventilator were similar. Data were collected at the same time points to compare the relativity among these three kinds of monitor., Results: Linear relative analysis showed a good relativity in PiCCO/Swan-Ganz (r=0.883), NICO/Swan-Ganz (r=0.853) and PiCCO/NICO (r=0.857) in cardiac index (CI)., Conclusion: PiCCO and NICO can be used as reliable measure to monitor ventilated patients bedside in intensive care unit (ICU), thus offering an assistance to optimize therapeutic strategy.

Objective: To observe the effect on mechanical ventilation with biphasic positive airway pressure (BIPAP), pressure support ventilation (PSV) and proportional pressure support (PPS) modes on hemodynamics in patients with either normal cardiac function or impaired cardiac function in order to optimize the time to wean mechanical ventilation in patients with severe cardiac dysfunction., Methods: Non-invasive cardiac output (NICO) monitoring was instituted in patients 32 with respiratory failure due to different causes, when spontaneous respiration was restored, and they were separated into two groups depending on whether the cardiac index (CI) was normal (CI> or =2.0 L.min(-1).m(-2)) or not (CI<2.0 L.min(-1).m(-2)). The effects of BIPAP, PSV and PPS modes on changes in hemodynamics were compared between two groups., Results: (1) In patients with normal cardiac function, CO, CI, stroke volume (SV), pulmonary capillary blood flow (PCBF) were significant higher in PSV and PPS modes than BIPAP mode, and they were highest with PPS mode, but no significant difference compared with PSV. Surround vascular resistance (SVR) was reduced significantly in PPS mode compared with BIPAP, but no significant difference was found compared with PSV. (2) In patients with cardiac dysfunction, CO, CI increased gradually when ventilated in BIPAP, PSV, PPS modes and significant difference was found among three groups. In PPS mode, CO and CI were highest. (3) The trends of peak airway pressure (Ppeak) and mean airway pressure (Pmean) were degressive in three groups. In both normal cardiac function group and cardiac dysfunction group, significant difference was found in PSV and PPS modes compared with BIPAP. Ppeak was lowest in PPS mode in cardiac dysfunction group, and there was significant difference compared with the other groups. (4) The ventilated time was significant reduced in PPS mode compared with PSV. (5) In normal cardiac function group, instinct positive end expiratory pressure (PEEPi) showed degressive trend among three different modes, and it was lowest in PPS mode, with significant difference compared with the other two groups., Conclusion: In PPS mode, the effect to hemodynamics in patients with severe cardiac dysfunction is minimal, so it is suitable as a weaning mode in this groups of patients.

Objective: To compare the effects on hemodynamics and lung mechanics when different positive end expiratory pressure (PEEP) levels were used in acute cardiac pulmonary edema., Methods: Thirty-nine patients with respiratory failure and treated with mechanical ventilation were divided into two groups according to cardiac index (CI). The changes of hemodynamics [including cardiac output (CO), CI, pulmonary capillary blood flow (PCBF), central venous pressure (CVP), surround vascular resistance (SVR)], lung mechanical variables [intrinsic positive end expiratory pressure (PEEPi), peak inspiratory pressure (Ppeak), mean of airway pressure (Pmean), minute volume (MV), alveolar tidal volume (Vtalv)], percutaneous saturation of oxygen (SpO(2)) and blood pressure (BP) were determined with when selected different PEEP levels under the bi-level positive airway pressure (BIPAP) mode in normal cardiac function group (n=18, CI> or =2.0 L.min(-1).m(-2)) and poor cardiac function group (n=20, CI<2.0 L.min(-1)xm(-2))., Results: In normal cardiac function group, PEEP has no effect on hemodynamics when varied from 0-13 cm H(2)O (1 cm H(2)O=0.098 kPa), and Ppeak and PEEPi increased with the elevation of PEEP. Resistance of airway (R) fell when PEEP was increased. However, in poor cardiac function group SVR, CO, CI showed curvilinear changes with an increase in PEEP, and CO, CI were high when PEEP changed from 0 to 7 cm H(2)O, but dropped markedly when PEEP was increased in 13 cm H(2)O, while the changes of SVR was the reverse of CO and CI. The effects on lung mechanics varied relatively smaller range when PEEP was set between 5-7 cm H(2)O, and the burden of breathing was slight., Conclusion: The mode of artificial ventilation should be adjusted according to the changes in hemodynamics and lung mechanics. PEEP should be individualized, and 5-7 cm H(2)O (normally below 10 cm H(2)O) is suitable.

Objective: To explore the use of second derivate in seeking the inflection points of pressure-volume (P-V) curves and compare it with the step-by-step regression method., Methods: Under general anesthesia, tracheotomy was done in 6 adult sheep, warm physiological saline was used to lavage the respiratory, followed by alveolar lavaged via tract through bronchofiberscope to reproduce acute respiratory distress syndrome (ARDS). The low flow technique was used to trace the P-V curves before and after the saline lavage, and features of the curves were analyzed with the software of Findgraph., Results: The above two methods fit the P-V data well with good accuracy both in inflation and deflation limbs in normal and ARDS animals. From the graph of second derivate, the characteristic points of the P-V curves could be exactly obtained, and the low inflection points obtained by this method were well correlated with lower inflection point (LIP) +2 cm H(2)O (1 cm H(2)O=0.098 kPa) obtained by step-by-step regression method., Conclusion: The graph of second derivate gained from P-V curves is useful to describe the inflection points, so that it can be helpful in instructing in setting the required parameters of the ventilator in the treatment of ARDS.

Objective: To study the effects of different levels of positive end expiratory pressure (PEEP) on recruitment and hemodynamics after sustained inflation in acute respiratory distress syndrome (ARDS) in sheep., Methods: Twelve adult sheep were anaesthetized and ARDS was induced by lung lavage with warm normal saline. Pressure-volume (P-V) curves were traced using the low flow technique and the upper inflection point (UIP) was determined. Sustained inflation was exercised at the pressure of 5 cm H(2)O (1 cm H(2)O=0.098 kPa) below UIP, and the sheep were divided into groups according to different PEEP levels (PEEP5, PEEP10, PEEP15, PEEP20). Hemodynamics and lung mechanics values were recorded during the 2 hours of recruitment, and biopsy was performed at the end of the trial., Results: There was no effect on hemodynamics and recruitment in 2 hours in PEEP5 and PEEP10 groups, but oxygenation was found to be decreased in PEEP5 group, and focal alveolar collapse was found in pathological examination. When the PEEP level reached 15 cm H(2)O, there was significant elevation in central venous pressure (CVP), and cardiac index (CI) fell remarkably, but oxygenation index and lung mechanics were improved and stable in 2 hours., Conclusion: Our study demonstrates that it can obviously improve oxygenation when PEEP is set at 10-20 cm H(2)O, oxygenation can be obviously improved, with little disturbance to hemodynamics in case cardiac function is normal.

Objective: To evaluate the effects of airway pressure release ventilation (APRV) and continuous positive airway pressure (CPAP) on hemodynamics, lung mechanics and oxygen metabolism index., Methods: Fifteen ARDS cases ventilated and monitored by the pulse contour method (PiCCO) were randomized into APRV group and CPAP group, then lung recruitment maneuver (RM) was executed every 4 hours. In APRV group, Phigh was 35 cm H(2)O (1 cm H(2)O=0.098 kPa) and Plow was set at lower inflection point (LIP) of the static pressure-volume (P-V) curve. In CPAP group, CPAP was also 35 cm H(2)O. The duration of RM in both groups was 40 seconds. Before and after RM the parameters of lung mechanics, oxygen metabolism index and hemodynamics were monitored and compared., Results: (1) In APRV group cardiac index (CI) was decreased slightly during RM with shorter duration than CPAP group. (2) The parameters of lung mechanics and oxygenation were improved significantly in both groups, and they were better in APRV group than CPAP group., Conclusion: In APRV group sedation can be abstained during RM, and the hemodynamics were hardly disturbed. Improvement of lung mechanics and oxygenation is much better with APRV than CPAP mode.

Objective: To evaluate the effects of lung recruitment maneuver (RM) on hemodynamics and lung structure with sustained inflation (SI) in acute respiratory distress syndrome (ARDS) in sheep, to look for a safe range of pressure and time of SI., Methods: Fourteen anaesthetized sheep were subjected to lung lavage through a broncho-fibroscope to reproduce ARDS, and quasi-static pressure-volume (P-V) curves were obtained with low flow technique. The upper inflection point (UIP) and the lower inflection point (LIP) were found, and then 5 cm H(2)O (1 cm H(2)O=0.098 kPa) below UIP, UIP, 10 cm H(2)O above UIP, 20 cm H(2)O above UIP as the peak pressure of SI were selected as the test pressure. They were randomized to four groups (U-5, U+0, U+10, U+20). The duration of SI was 60 seconds. Hemodynamics and oxygenation indexes were monitored and recorded during and after SI until the study was terminated 2 hours later, then CT and lung tissue biopsy were performed., Results: Pneumothorax was found in U+20 groups, resulting in the death of sheep. Hemodynamics was affected significantly in other groups during SI. In U+10 groups, cardiac output (CO) and cardiac index (CI) were lowered at 15 seconds after RM began, and recovered slowly after RM; in U+0 group and U-5 group, the entire RM could be carried out to the end, and biopsy showed bullous emphysema in U+0 group., Conclusion: The impairment of the hemodynamics and damage to the lung structure should be prevented when RM is performed in ARDS patients, and the inflation pressure should be limited within the range of UIP or 5 cm H(2)O under UIP to avoid adverse effect on hemodynamics.