This paper presents a new method for the detection and parameter estimation of multicomponent LFM signals based on the fractional Fourier transform. For the optimization in the fractional Fourier domain, an algorithm ...This paper presents a new method for the detection and parameter estimation of multicomponent LFM signals based on the fractional Fourier transform. For the optimization in the fractional Fourier domain, an algorithm based on Quasi-Newton method is proposed which consists of two steps of searching, leading to a reduction in computation without loss of accuracy. And for multicomponent signals, we further propose a signal separation technique in the fractional Fourier domain which can effectively suppress the interferences on the detection of the weak components brought by the stronger components. The statistical analysis of the estimate errors is also performed which perfects the method theoretically, and finally, simulation results are provided to show the validity of our method.展开更多
AIM: To evaluate the feasibility, safety, and tolerance of early removing gastrointestinal decompression and early oral feeding in the patients undergoing surgery for colorectal carcinoma. METHODS: Three hundred and...AIM: To evaluate the feasibility, safety, and tolerance of early removing gastrointestinal decompression and early oral feeding in the patients undergoing surgery for colorectal carcinoma. METHODS: Three hundred and sixteen patients submitted to operations associated with colorectostorny from January 2004 to September 2005 were randomized to two groups: In experimental group (n = 161), the nasogastric tube was removed after the operation from 12 to 24 hours and was promised immediately oral feeding; In control group (n = 155), the nasogastric tube was maintained until the passage of flatus per rectum. Variables assessed included the time to first passage of flatus, the time to first passage of stool, the time elapsed postoperative stay, and postoperative complications such as anastornotic leakage, acute dilation of stomach, wound infection and dehiscense, fever, pulmonary infection and pharyngolaryngitis. RESULTS: The median and average days to the first passage of flatus (3.0±0.9 vs 3.6±1.2, P〈0.001), the first passage of stool (4.1± 1.1 vs 4.8±1.4 P〈0.001) and the length of postoperative stay (8.4±3.4 vs 9.6±5.0, P〈0.05) were shorter in the experimental group than in the control group. The postoperative complications such as anastomotic leakage (1.24% vs 2.58%), acute dilation of stomach (1.86% vs 0.06%) and wound complications (2.48% vs 1.94%) were similar in the groups, but fever (3.73% vs 9.68%, P〈0.05), pulmonary infection (0.62% vs 4.52%, P〈0.05) and pharyngolaryngitis (3.11% vs 23.23%, P〈0.001) were much more in the control group than in the experimental group. CONCLUSION: The present study shows that applicationof gastrointestinal decompression after colorectostomy can not effectively reduce postoperative complications. On the contrary, it may increase the incidence rate of fever, pharyngolaryngitis and pulmonary infection. These strategies of early removing gastrointestinal decompression and early oral feeding in the patients underg展开更多
Background: With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term ontcome...Background: With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term ontcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China. Methods: All infants admitted to 26 NICUs with a birth weight (BW) 〈1000 g were included between January 1,2011 and December 31,2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors. Results: A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age (GA) was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants (23.3%) died and another 69 infants (26.7%) died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas (53.6% vs. 35.3%, P = 0.019). BW 〈750 g and GA 〈28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions: Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.展开更多
Sawuer region is located in west Junggar, Jimunai County of Altay district and Hefeng County of Tacheng district, Xinjiang. The region is along the north margin of Kazakstan-Junggar plate. The intrusions (mainly acid)...Sawuer region is located in west Junggar, Jimunai County of Altay district and Hefeng County of Tacheng district, Xinjiang. The region is along the north margin of Kazakstan-Junggar plate. The intrusions (mainly acid) are widespread. Qiaqihai and Kuoyitasi intrusions are important in the region, with the characteristics of A-type granite. Further investigations indicate that they belong to A2-type granite that formed in extension tectonic setting of post collision. The REE chon-drite-normalized patterns of the intrusions show LREE enrichment and the δ Eu values are lower. The Nd, Sr, Pb isotope compositions of the intrusions indicate a mantle source, while the low δ 18O values resulted from the isotope exchange between intrusion and meteoric water. According to SHRIMP U-Pb age analysis results, the crystallization age of Qiaqihai intrusion is 290.7 ± 9.3 Ma (1σ ), and that of Kuoyitasi intrusion is 297.9 ± 4.6 Ma (1σ ), corresponding to the beginning of early Permian. The A2-type granites indicate that the region was in the extension period of the post-collisional stage at the beginning of early Permian in the Sawuer region. The A-type granites in the Sawuer region in west Junggar discovered from this work is analogous to the A-type granites found in east Junggar of the Ulungur alkali granites belt. The confirmation of post-collisional A-type granites of early Permian in the Sawuer region provides new evidence for the regional vertical continental crust growth in early Per-mian. The former proposed Ulungur alkali granites belt can extend from east Ulungur through west Ulungur and to Zhaisang in Kazakstan westwards.展开更多
文摘This paper presents a new method for the detection and parameter estimation of multicomponent LFM signals based on the fractional Fourier transform. For the optimization in the fractional Fourier domain, an algorithm based on Quasi-Newton method is proposed which consists of two steps of searching, leading to a reduction in computation without loss of accuracy. And for multicomponent signals, we further propose a signal separation technique in the fractional Fourier domain which can effectively suppress the interferences on the detection of the weak components brought by the stronger components. The statistical analysis of the estimate errors is also performed which perfects the method theoretically, and finally, simulation results are provided to show the validity of our method.
文摘AIM: To evaluate the feasibility, safety, and tolerance of early removing gastrointestinal decompression and early oral feeding in the patients undergoing surgery for colorectal carcinoma. METHODS: Three hundred and sixteen patients submitted to operations associated with colorectostorny from January 2004 to September 2005 were randomized to two groups: In experimental group (n = 161), the nasogastric tube was removed after the operation from 12 to 24 hours and was promised immediately oral feeding; In control group (n = 155), the nasogastric tube was maintained until the passage of flatus per rectum. Variables assessed included the time to first passage of flatus, the time to first passage of stool, the time elapsed postoperative stay, and postoperative complications such as anastornotic leakage, acute dilation of stomach, wound infection and dehiscense, fever, pulmonary infection and pharyngolaryngitis. RESULTS: The median and average days to the first passage of flatus (3.0±0.9 vs 3.6±1.2, P〈0.001), the first passage of stool (4.1± 1.1 vs 4.8±1.4 P〈0.001) and the length of postoperative stay (8.4±3.4 vs 9.6±5.0, P〈0.05) were shorter in the experimental group than in the control group. The postoperative complications such as anastomotic leakage (1.24% vs 2.58%), acute dilation of stomach (1.86% vs 0.06%) and wound complications (2.48% vs 1.94%) were similar in the groups, but fever (3.73% vs 9.68%, P〈0.05), pulmonary infection (0.62% vs 4.52%, P〈0.05) and pharyngolaryngitis (3.11% vs 23.23%, P〈0.001) were much more in the control group than in the experimental group. CONCLUSION: The present study shows that applicationof gastrointestinal decompression after colorectostomy can not effectively reduce postoperative complications. On the contrary, it may increase the incidence rate of fever, pharyngolaryngitis and pulmonary infection. These strategies of early removing gastrointestinal decompression and early oral feeding in the patients underg
文摘Background: With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term ontcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China. Methods: All infants admitted to 26 NICUs with a birth weight (BW) 〈1000 g were included between January 1,2011 and December 31,2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors. Results: A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age (GA) was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants (23.3%) died and another 69 infants (26.7%) died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas (53.6% vs. 35.3%, P = 0.019). BW 〈750 g and GA 〈28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions: Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.
文摘Sawuer region is located in west Junggar, Jimunai County of Altay district and Hefeng County of Tacheng district, Xinjiang. The region is along the north margin of Kazakstan-Junggar plate. The intrusions (mainly acid) are widespread. Qiaqihai and Kuoyitasi intrusions are important in the region, with the characteristics of A-type granite. Further investigations indicate that they belong to A2-type granite that formed in extension tectonic setting of post collision. The REE chon-drite-normalized patterns of the intrusions show LREE enrichment and the δ Eu values are lower. The Nd, Sr, Pb isotope compositions of the intrusions indicate a mantle source, while the low δ 18O values resulted from the isotope exchange between intrusion and meteoric water. According to SHRIMP U-Pb age analysis results, the crystallization age of Qiaqihai intrusion is 290.7 ± 9.3 Ma (1σ ), and that of Kuoyitasi intrusion is 297.9 ± 4.6 Ma (1σ ), corresponding to the beginning of early Permian. The A2-type granites indicate that the region was in the extension period of the post-collisional stage at the beginning of early Permian in the Sawuer region. The A-type granites in the Sawuer region in west Junggar discovered from this work is analogous to the A-type granites found in east Junggar of the Ulungur alkali granites belt. The confirmation of post-collisional A-type granites of early Permian in the Sawuer region provides new evidence for the regional vertical continental crust growth in early Per-mian. The former proposed Ulungur alkali granites belt can extend from east Ulungur through west Ulungur and to Zhaisang in Kazakstan westwards.