3,220 research outputs found
Residence of Habitat-Specific Anammox Bacteria in the Deep-Sea Subsurface Sediments of the South China Sea: Analyses of Marker Gene Abundance with Physical Chemical Parameters
Anaerobic ammonium oxidation (anammox) has been recognized as an important process for the global nitrogen cycle. In this study, the occurrence and diversity of anammox bacteria in the deep-sea subsurface sediments of the South China Sea (SCS) were investigated. Results indicated that the anammox bacterial sequences recovered from this habitat by amplifying both 16S rRNA gene and hydrazine oxidoreductase encoding hzo gene were all closely related to the Candidatus Scalindua genus. A total of 96 16S rRNA gene sequences from 346 clones were grouped into five subclusters: two subclusters affiliated with the brodae and arabica species, while three new subclusters named zhenghei-I, -II, and -III showed ≤97.4% nucleic acid sequence identity with other known Candidatus Scalindua species. Meanwhile, 88 hzo gene sequences from the sediments also formed five distant subclusters within hzo cluster 1c. Through fluorescent real-time PCR analysis, the abundance of anammox bacteria in deep-sea subsurface sediment was quantified by hzo genes, which ranged from 1.19 × 104 to 7.17 × 104 copies per gram of dry sediments. Combining all the information from this study, diverse Candidatus Scalindua anammox bacteria were found in the deep-sea subsurface sediments of the SCS, and they could be involved in the nitrogen loss from the fixed inventory in the habitat
Inhibition of Arterial Allograft Intimal Hyperplasia Using Recipient Dendritic Cells Pretreated with B7 Antisense Peptide
Background. Low expression or absence of dendritic cell (DC) surface B7 molecules can induce immune tolerance or hyporesponse. Whether DCs could induce indirect allogeneic-specific cross-tolerance or hyporesponse to recipient T cells remains unclear. Methods. Generated from C3H/He mice bone marrow cells pulsed with donor antigen from C57BL/6 mice, recipient DCs were incubated with B7 antisense peptide (B7AP). Immune regulatory activities were examined in vitro by a series of mixed lymphocyte reactions. Murine allogeneic carotid artery orthotopic transplantation was performed from C57BL/6 to C3H/He. Recipients were given B7AP-treated DCs 7 days before transplantation. Allograft pathological analysis was done 2 months after transplantation. Results. B7AP-pretreated DCs markedly inhibited T-cell proliferation compared with untreated group. Pretreated T cells exhibited markedly reduced response to alloantigen versus third-party antigen. Pathological analysis of arterial allografts demonstrated significant reduction of intimal hyperplasia in B7-AP pretreated group versus control. Conclusion. Blockade of B7 molecules by B7AP could induce indirect allogeneic-specific hyporesponse and inhibit arterial allograft intimal hyperplasia, which may be involved in future strategies for human allograft chronic rejection
Prognosis of Stage IV Gastric Cancer Patients
Aim. This study evaluated the survival of gastric cancer patients with metastasis to the hepatoduodenal, retropancreatic, mesenteric, and para-aortic lymph nodes. Materials and methods. We analyzed the survival rate of 435 gastric cancer patients who underwent operation from 2001 to 2010 at the Department of Surgery, Chonnam National University Hospital. There were 43, 25, 16, and 55 patients with metastasis to the hepatoduodenal, retropancreatic, mesenteric, and para-aortic nodes, respectively. Results. Based on tumor location, metastasis to the para-aortic lymph nodes was more common in upper-third cancer, and that to the hepatoduodenal lymph nodes was more common in lower-third cancer. The survival rate of patients with non-regional lymph node metastasis was better than that of patients with hepatic metastasis or peritoneal dissemination (p < 0.05). Conclusion. We recommend performing a more extended lymphadenectomy than a D2 lymphadenectomy in patients with advanced gastric cancer those having metastasis to the hepatoduodenal nodes
A Flexible Sensor and MIMU-Based Multisensor Wearable System for Human Motion Analysis
Motivation: Magnetic–inertial measurement units (MIMUs) and flexible sensors are widely used in the wearable measurement system for human motion monitoring, clinical gait detection, and robotics motion control. However, MIMUs demonstrate measurement error due to magnetic disturbance in the indoor environment, and flexible sensors usually have low performance on linearity and accuracy. Objective: This article is intended to eliminate the low-accuracy problem caused by magnetic disturbances and improve the measurement accuracy of MIMU–flexible-sensor-based wearable systems. Approach: 1) a three-stage real-time adaptive anti-disturbance data fusion (RT-ADF) algorithm is proposed, which contains an anti-disturbance filter based on a double Mahony filter along with a state observer, a signal holder for sensors’ data transmit synchronously, and a data fusion based on an adaptive Kalman filter; 2) the proposed algorithm is used and validated its performance on a designed MIMU–flexible sensor wearable system; and 3) ten groups of knee motions (flexion/extension), ten groups of hip motions (adduction/abduction), and ten groups of elbow motions (flexion/extension) have been done by seven subjects in the experiments. Main Results: The designed multisensor wearable system based on the presented data fusion algorithm demonstrates a high-accuracy performance under the magnetic disturbance environment, and the maximum root mean square error (RMSE) of the measured continuous 3-D motion angle of the knee, hip, and elbow cross all the experiments was 1.23°, 1.15°, and 3.67° for each axis.<br/
Searching for short-period variables in M31: method and catalogs
Utilizing high-cadence and continuous g- and r-band data over three nights
acquired from the 3.6-meter Canada France Hawaii Telescope (CFHT) aimed to find
short-duration microlensing events, we conduct a systematic search for
variables, transients, and asteroids across a field of view of
the Andromeda Galaxy (M 31). We present a catalog of 5859 variable stars,
yielding the most extensive compilation of short-period variable sources of M
31. We also detected 19 flares, predominantly associated with foreground M
dwarfs in the Milky Way. In addition, we discovered 17 previously unknown
asteroid candidates, and we subsequently reported them to the Minor Planet
Center. Lastly, we report a microlensing event candidate C-ML-1 and present a
preliminary analysis
A Flexible Sensor and MIMU-Based Multisensor Wearable System for Human Motion Analysis
Motivation: Magnetic–inertial measurement units (MIMUs) and flexible sensors are widely used in the wearable measurement system for human motion monitoring, clinical gait detection, and robotics motion control. However, MIMUs demonstrate measurement error due to magnetic disturbance in the indoor environment, and flexible sensors usually have low performance on linearity and accuracy. Objective: This article is intended to eliminate the low-accuracy problem caused by magnetic disturbances and improve the measurement accuracy of MIMU–flexible-sensor-based wearable systems. Approach: 1) a three-stage real-time adaptive anti-disturbance data fusion (RT-ADF) algorithm is proposed, which contains an anti-disturbance filter based on a double Mahony filter along with a state observer, a signal holder for sensors’ data transmit synchronously, and a data fusion based on an adaptive Kalman filter; 2) the proposed algorithm is used and validated its performance on a designed MIMU–flexible sensor wearable system; and 3) ten groups of knee motions (flexion/extension), ten groups of hip motions (adduction/abduction), and ten groups of elbow motions (flexion/extension) have been done by seven subjects in the experiments. Main Results: The designed multisensor wearable system based on the presented data fusion algorithm demonstrates a high-accuracy performance under the magnetic disturbance environment, and the maximum root mean square error (RMSE) of the measured continuous 3-D motion angle of the knee, hip, and elbow cross all the experiments was 1.23°, 1.15°, and 3.67° for each axis.<br/
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