Search

An infinite-equilibria memristive chaotic system (MCS) with plentiful parameter-relied and initial-relied dynamics is constructed from a six-term three-dimensional (3D) system by leading into a flux-controlled memristor. The stabilities of equilibria and dynamical behaviors are discussed. Period-doubling bifurcation corresponds to system parameters and initial values are investigated to reveal its chaos generation. Infinite coexisting chaotic and periodic attractors are discovered in the system by using bifurcation diagrams and phase portraits. Changing multiple parameters of the system, the oscillation amplitude of variables increase or decrease accordingly, yielding the amplitude control feature. Not only the parameter-relied amplitude control, but also the initial-relied amplitude control is found as well. Moreover, the circuit implementation is given to support the physical existence and reliability of the system. [ABSTRACT FROM AUTHOR]

Paleogeographic reconstructions of the Lhasa terrane for the Cretaceous provide important constraints on the evolution of the Neo-Tethys Ocean and crustal shortening within Asia. However, the Cretaceous paleogeography of the Lhasa terrane remains contentious. A direct way to study this issue is to conduct paleomagnetic investigations of the Cretaceous rocks of the Lhasa terrane; however, most previous Cretaceous paleomagnetic investigations of the Lhasa terrane were conducted in the middle and western segments of this terrane. Different vertical-axis rotations affected different parts of the Lhasa terrane following the India-Asia collision, and therefore paleomagnetic data from the western and middle segments of the Lhasa terrane cannot necessarily be used to directly constrain the paleolatitudes of its eastern segment. This study presents paleomagnetic data from the Early Cretaceous volcanic rocks with well-constrained ages from the Luolong area in the eastern segment of the Lhasa terrane. Isotope geochronology reveals that these rocks formed at 127–124 Ma. The mean high-temperature direction obtained from 17 paleomagnetic sites is declination/inclination (Ds/Is) = 21.8°/19.0° with ks = 65.8 and α95 = 4.4° (k—best estimate of the precision parameter; α95—radius of the 95% probability ellipse around the mean direction; s—stratigraphic coordinates). Petrographic investigations, a positive fold test, a reversal test, and a paleosecular variation test indicate the primary origin of this characteristic remanence. A paleomagnetic pole of 60.9°N, 227.2°E with dp/dm = 2.4°/4.6° (dp/dm—semi-axes of the 95% probability ellipse around the mean pole) yields a paleolatitude of 9.2 ± 2.4°N for the eastern segment of the Lhasa terrane. Combined with reliable results from previous paleomagnetic studies, we draw the following conclusions. (1) During the Early Cretaceous, the Lhasa terrane was oriented WNW-ESE as a whole, and the eastern-middle segments may have been oriented nearly E-W. (2) Asia has accommodated 2050 ± 230 km of N-S crustal shortening along 96°E longitude since the Early Cretaceous. (3) The minimum N-S width of the Neo-Tethys Ocean at ca. 125 Ma was 4185 ± 300 km. [ABSTRACT FROM AUTHOR]

During the cracking process of hydrocarbon fuel, the heat would be converted into internal energy and chemical energy. It is necessary to study the conversion relationship between internal energy and chemical energy in the above-mentioned energy conversion process, which is of great significance for the efficient use of fuel heat sinks in the regenerative cooling process. Therefore, the influences of pressure, mass flow rate, wall heat flux, and heating rate on the energy conversion were investigated, and an empirical prediction model was developed. The numerical results revealed that the influence of pressure on heat sink mainly focuses on the low and medium conversion. The chemical heat sink decreases with the increase of the mass flow rate and the heating rate, while the chemical heat sink increases with the increase in the wall heat flux. In addition, based on the analysis of the numerical data, an energy conversion correlation is developed by the Buckingham PI theorem, and most of the data calculated by this correlation can satisfy the deviation bandwidth of ±10%. [ABSTRACT FROM AUTHOR]

Objective • The study aimed to evaluate the impact of OLIF on spinal-pelvic sagittal parameters and its correlation with clinical outcomes in patients with degenerative lumbar spondylolisthesis. Methods • A retrospective analysis of 43 patients (23 males, 20 females) with lumbar 4/5 degenerative spondylolisthesis who underwent OLIF from January 2018 to January 2023 was conducted. Key parameters studied included SP, DH, FH, AS, LL, SS, PT, PI, and LASD. Results • All surgeries were successfully completed according to the original plan, and the minimum followup time was greater than 6 months, with a mean operation time of 198.21±51.32 min; the mean intraoperative bleeding volume was 121.00±56.88 ml. The VAS score of lumbar pain and ODI index decreased from the preoperative VAS score, and the ODI index of lower lumbar pain from the preoperative VAS score of 6.50±1.36 and 74.36±6.27 to the postoperative Lumbar pain of 3.20±1.28 and 32.41±8.21, respectively, and the differences were statistically significant (P < .05). 6.27 to 3.20±1.28 and 32.41±8.21 at the final follow-up visit. The differences were statistically significant (P < .05). The results of Pearson correlation analysis showed positive correlation between postoperative LL and FH, SP and AS, VAS (P < .05), and service correlation between SP and SS, LASD (P < .05), and correlation between pre- and postsurgery difference of LL, FH, SP and the improvement rate of ODI and VAS scores (P < .05), with the difference of pre- and post-surgery difference of LL, FH and the ODI, VAS score improvement rate were the strongest correlation. Postoperatively, significant improvements were observed in LL and FH. Pearson correlation analysis indicated a positive correlation between changes in sagittal parameters and clinical outcomes, measured by VAS and ODI scores. Conclusion • The postoperative spine-pelvis sagittal parameters were significantly improved compared with the preoperative ones, and the changes of the spine-pelvis sagittal parameters before and after the operation were correlated with the clinical outcomes, among which the differences of LL and FH had the strongest correlation with the improvement rates of ODI and VAS scores. OLIF effectively improved spinal-pelvic sagittal parameters and clinical outcomes in degenerative lumbar spondylolisthesis, with changes in LL and FH showing the strongest correlation with patient-reported outcome improvements. An oblique lateral interbody fusion can effectively reconstruct spine-pelvis sagittal parameters in patients with degenerative lumbar spondylolisthesis. [ABSTRACT FROM AUTHOR]

The complex pathology of chronic thoracic spinal cord compression involves vascular and neuroarchitectural repair processes that are still largely unknown. In this study, we used synchrotron radiation microtomography (SRμCT) to quantitatively characterize the 3D temporal-spatial changes in the vascular and neuronal network after chronic thoracic spinal cord compression in order to obtain further insights into the pathogenesis of this disease and to elucidate its underlying mechanisms. Direct 3D characterization of the spinal cord microvasculature and neural microstructure of the thoracic spinal cord was successfully reconstructed. The significant reduction in vasculature and degeneration of neurons in the thoracic spinal cord visualized via SRμCT after chronic compression were consistent with the changes detected by immunofluorescence staining. The 3D morphological measurements revealed significant reductions of neurovascular parameters in the thoracic spinal cord after 1 month of compression and became even worse after 6 months without relief of compression. In addition, the distinct 3D morphological twist and the decrease in branches of the central sulcal artery after chronic compression vividly displayed that these could be the potential triggers leading to blood flow reduction and neural deficits of the thoracic spinal cord. Our findings propose a novel methodology for the 3D analysis of neurovascular repair in chronic spinal cord compression, both qualitatively and quantitatively. The results indicated that compression simultaneously caused vascular dysfunction and neuronal network impairment, which should be acknowledged as concurrent events after chronic thoracic spinal cord injury. Combining neuroprotection with vasoprotection may provide promising therapeutic targets for chronic thoracic spinal cord compression. [ABSTRACT FROM AUTHOR]

The complex pathology of chronic thoracic spinal cord compression involves vascular and neuroarchitectural repair processes that are still largely unknown. In this study, we used synchrotron radiation microtomography (SRμCT) to quantitatively characterize the 3D temporal -spatial changes in the vascular and neuronal network after chronic thoracic spinal cord compression in order to obtain further insights into the pathogenesis of this disease and to elucidate its underlying mechanisms. Direct 3D characterization of the spinal cord microvasculature and neural microstructure of the thoracic spinal cord was successfully reconstructed. The significant reduction in vasculature and degeneration of neurons in the thoracic spinal cord visualized via SRμCT after chronic compression were consistent with the changes detected by immunofluorescence staining. The 3D morphological measurements revealed significant reductions of neurovascular parameters in the thoracic spinal cord after 1 month of compression and became even worse after 6 months without relief of compression. In addition, the distinct 3D morphological twist and the decrease in branches of the central sulcal artery after chronic compression vividly displayed that these could be the potential triggers leading to blood flow reduction and neural deficits of the thoracic spinal cord. Our findings propose a novel methodology for the 3D analysis of neurovascular repair in chronic spinal cord compression, both qualitatively and quantitatively. The results indicated that compression simultaneously caused vascular dysfunction and neuronal network impairment, which should be acknowledged as concurrent events after chronic thoracic spinal cord injury. Combining neuroprotection with vasoprotection may provide promising therapeutic targets for chronic thoracic spinal cord compression. [ABSTRACT FROM AUTHOR]

Purpose: To explore the molecular function of miR-196b-5p in hepatocellular carcinoma (HCC). Methods: MiR-196b-5p expression levels in HCC tissue samples were assessed by qRT-PCR. MiR- 196b-5p was knocked-down or over-expressed in HepG2 cells by transfecting the cells with plasmids expressing either a miR-196b-5p inhibitor or mimic, respectively, while cell proliferation was assessed by MTT assay. The interaction of miR-196b-5p with target molecules was confirmed using luciferase reporter assay. Cell cycle was investigated by flow cytometry, while NFkBIA expression was assessed by western blotting. Results: MiR-196b-5p was over-expressed in HCC, and miR-196b-5p expression levels in patients with HCC were related to tumor grade. MiR-196b-5p over-expression promoted cell proliferation and colony formation and suppressed cell cycle arrest and apoptosis. The results of luciferase reporter assay showed that miR-196b-5p reduced NFkBIA expression in HepG2 cells by binding to a response element in the 3' UTR of NFkBIA. Further investigation showed that NFkBIA interacts with NFkB1 and reduces the concentration of NFkB1 in HepG2 cells. The promoter of ATP-binding cassette sub-family B member 1 (ABCB1) was also targeted and bound by NFkB1, which altered the expression of ABCB1 in HepG2 cells. Conclusion: MiR-196b-5p regulates cell proliferation in drug-resistant HCC cell lines via activation of the NFkB/ABCB1 signaling pathway. [ABSTRACT FROM AUTHOR]

Purpose: To explore the antitumor activity of wogonoside on bladder cancer, and its underlying mechanism of action. Methods: Methyl thiazolyl tetrazolium (MTT) assay was applied to evaluate the anti-proliferative activity of wogonoside (2 - 128 μM) against bladder cancer 5637 cell line at different times, and the half maximal inhibitory concentration (IC50) was measured. The antitumor activity of wogonoside (30 mg/kg, i.p.) against bladder cancer 5637 cell line was confirmed via in vivo experiments on nude mice bearing human bladder cancer 5637 cells. Additionally, western blotting assay and enzyme-linked immunosorbent assay (ELISA) were used to investigate expression levels of caspase-3, caspase-9, B cell lymphoma/leukemia-2 (Bcl-2), Bcl-2 associated X protein (Bax), phosphorylated (p)-glycogen synthase kinase (GSK)-3β, p-extracellular signal-regulated kinases (p-ERK), and p-(protein kinase B) AKT. Results: The in vitro results reveal that wogonoside has remarkable anti-proliferative activity against bladder cancer 5637 cells with IC50 of 20.59 μM, in a concentration-and time-dependent manner. Furthermore, wogonoside treatment also suppressed tumor volume of nude mice bearing bladder cancer 5637 cell (p < 0.01). The potential mechanisms seems to be mainly associated with apoptosis mediated by mitochondria via up-regulation of caspase-3, caspase-9, and Bax levels, and downregulation of Bcl-2, p-GSK-3β, p-ERK, and p-AKT. Conclusion: The results reveal that wogonoside possesses anti-tumor potentials against bladder cancer. Further translational studies are warranted to test the clinical application of this medicinal agent in bladder cancer. [ABSTRACT FROM AUTHOR]

Purpose: To explore the antitumor activity of wogonoside on bladder cancer, and its underlying mechanism of action. Methods: Methyl thiazolyl tetrazolium (MTT) assay was applied to determine the anti-proliferative activity of wogonoside (2 - 128 μM) on bladder cancer 5637 cell line at various times, and the halfmaximal inhibitory concentration (IC50) was measured. The antitumor activity of wogonoside (30 mg/kg, ip) against bladder cancer 5637 cell line was evaluated in nude mice bearing human bladder cancer 5637 cells. Additionally, western blotting and enzyme-linked immunosorbent assay (ELISA) were carried out to investigate the levels of the caspase-3, caspase-9, B cell lymphoma/leukemia-2 (Bcl-2), Bcl-2 associated X-protein (Bax), phosphorylated (p)-glycogen synthase kinase (GSK)-3β, p-extracellular signal-regulated kinases (p-ERK), and p-(protein kinase B) AKT. Results: The in vitro results revealed that wogonoside exerted anti-proliferative activity against bladder cancer 5637 cells with an IC50 of 20.59 μM (p < 0.01), in a concentration- and time-dependent manner. Furthermore, wogonoside treatment also significantly suppressed tumor volume in mice (p < 0.01). The potential mechanisms were mainly associated with apoptosis mediated by mitochondria via upregulation of caspase-3, caspase-9, and Bax levels and down-regulation of Bcl-2, p-GSK-3β, p-ERK, and p-AKT. Conclusion: The results reveal that wogonoside has remarkable anti-tumor potentials against bladder cancer. Further translational studies are warranted to test the clinical application of this medicinal agent in bladder cancer. [ABSTRACT FROM AUTHOR]

Study Design: An advanced imaging of vasculature with synchrotron radiation X-ray in a rat model.Objective: To develop the potential for quantitative assessment of vessel network from two-dimensional (2D) to 3D visualization by synchrotron radiation X-ray phase contrast tomography (XPCT) in rat spinal cord model.Summary Of Background Data: Investigation of microvasculature contributes to the understanding of pathological development of spinal cord injury. A few of X-ray imaging is available to visualize vascular architecture without usage of angiography or invasive casting preparation.Methods: A rat spinal cord injury model was produced by modified Allen method. Histomorphometric detection was simultaneously analyzed by both histology and XPCT from 2D to 3D visualization. The parameters including tissue lesion area, microvessel density, vessel diameter, and frequency distribution of vessel diameter were evaluated.Results: XPCT rendered the microvessels as small as capillary scale with a pixel size of 3.7 μm. It presented a high linear concordance for characterizing the 2D vascular morphometry compared with the histological staining (r = 0.8438). In the presence of spinal cord injury model, 3D construction quantified the significant angioarchitectural deficiency in the injury epicenter of cord lesion (P<0.01).Conclusion: XPCT has a great potential to detect the smallest vascular network with pixel size up to micron dimension. It is inferred that the loss of abundant microvessels (≤40 μm) is responsible for local ischemia and neural dysfunction. XPCT holds a promise for morphometric analysis from 2D to 3D imaging in experimental model of neurovascular disorders.Level Of Evidence: N/A. [ABSTRACT FROM AUTHOR]

Aims: The purpose of this diagnostic meta-analysis was to explore the benefit of shear wave elastography (SWE) combinedly used with conventional ultrasound (US) in the diagnosis of the benign and malignant breast lesion.Material and Methods: After a literature search on MEDLINE, Cochrane library, and Embase we included 14 studies with a total 1951 patients and 2060 breast lesions for further analyses. Summary descriptive statistics such as pooled sensitivity, specificity, and summary receiver operating characteristics curve were generated via a bivariate random effect model. Summary indicators such as area under curve (AUC) and confident region were used to compare the performance of conventional US and combination of conventional US and shear wave imaging (SWI) or two-dimensional and three-dimensional SWI.Results: As indicated by the results, the pooled sensitivity, specificity, and diagnostic odds ratio for combined usage of SWE and the conventional US were 0.877 (95%CI: 0.855-0.896) and 0.849 (95%CI: 0.826-0.869) and 40.164 (95%CI:31.135- 51.811). The AUC for combined use and the conventional US only were 0.928 and 0.899, suggesting a promise of integrating SWE in the routine of breast lesion examination. Also, the summary AUC for 2D and 3D SWE were 0.917 and 0.952 respectively. No significant difference was found between 2D and 3D SWE. No obvious publication bias was identified after employing Deeks' regression test for asymmetry.Conclusion: Our analysis concluded that SWE improved the differential diagnosis of the breast lesion. [ABSTRACT FROM AUTHOR]

Zipf's law is an important linguistics law. In 1940s, Zipf found power law in the distribution of the word frequencies. The word rankings are in descending order of their occurrence frequencies. Through a series of experiments of random input letter sequences, the results show that the power law distribution has existed in not only natural language utterances but also random symbolic sequences. [ABSTRACT FROM AUTHOR]

Large-eddy simulations were used to investigate the supercritical aerodynamics of a square cylinder with rounded corners in comparison with those in the subcritical regime. First, the numerical methods, especially the dynamic mixed model, were validated on the basis of their prediction of supercritical flows past a circular cylinder. Then, the supercritical flows past a rounded-corner square cylinder were simulated and systematically clarified. Strong Reynolds number (Re) effects existed in the forces and local pressures as Re increased from o(104) to o(106). Changeover of flow patterns occurred as Re increased. At the supercritical Re, the free stream overall flowed along the cross sections of the cylinder, separated from the leeward corners and generated Karman vortices behind the cylinder. This pattern resulted in a much smaller recirculation region behind the cylinder compared with the subcritical flow. At the micro level, the flow experienced laminar separation and flow reattachment near the frontal corners, followed by the spatial development of turbulent boundary layers (TBLs) on the side faces and turbulent separation near the leeward corners. The feedback by large-scale primary vortex shedding and the small-scale turbulent motions in the high-frequency region with a slope of -5/3 were detected in the TBL. Their interaction affected the spanwise correlations of wall pressure fluctuations. The TBL on the side face differed from the zero-pressure-gradient flat-plate one; it was subjected to pressure gradients varying in space and time. [ABSTRACT FROM AUTHOR]

Background: Over the past few decades, there have been many studies of aspects of brain-computer interface (BCI). Of particular interests are event-related potential (ERP)-based BCI spellers that aim at helping mental typewriting. Nowadays, audiovisual unimodal stimuli based BCI systems have attracted much attention from researchers, and most of the existing studies of audiovisual BCIs were based on semantic incongruent stimuli paradigm. However, no related studies had reported that whether there is difference of system performance or participant comfort between BCI based on semantic congruent paradigm and that based on semantic incongruent paradigm.Methods: The goal of this study was to investigate the effects of semantic congruency in system performance and participant comfort in audiovisual BCI. Two audiovisual paradigms (semantic congruent and incongruent) were adopted, and 11 healthy subjects participated in the experiment. High-density electrical mapping of ERPs and behavioral data were measured for the two stimuli paradigms.Results: The behavioral data indicated no significant difference between congruent and incongruent paradigms for offline classification accuracy. Nevertheless, eight of the 11 participants reported their priority to semantic congruent experiment, two reported no difference between the two conditions, and only one preferred the semantic incongruent paradigm. Besides, the result indicted that higher amplitude of ERP was found in incongruent stimuli based paradigm.Conclusions: In a word, semantic congruent paradigm had a better participant comfort, and maintained the same recognition rate as incongruent paradigm. Furthermore, our study suggested that the paradigm design of spellers must take both system performance and user experience into consideration rather than merely pursuing a larger ERP response. [ABSTRACT FROM AUTHOR]

Endothelial cells (ECs) are confirmed as important regulators of vascular integrity, particularly in relation to angiogenesis, wound repair post-injury, and during embryogenesis. Futher, miRNAs have been implicated in EC function and proliferation. Moreover, knockdown of these miRNAs resulted in altered expressions of several important regulators of endothelial biology and angiogenesis including vascular endothelial growth factor receptor 2, endothelial nitric oxide synthase and tubule formation capacity. Several miRNAs have been identified to play a role in the regulation of function, proliferation and growth of vascular ECs. These miRNAs may be important therapeutic targets in the treatment of a range of ischemic diseases, as well as in the regulation of angiogenesis during cancer and tumour progression. The present review discuss some of the important miRNAs having confirmed regulatory role in EC in connection espically with cardiovascular disease. [ABSTRACT FROM AUTHOR]

Previous evidence has suggested that microRNAs (miRNAs or miRs), which belong to a class of non‑coding RNAs, shape cellular processes by regulating gene expression. Abnormal expression of miRNAs has been associated with tumorigenesis in multiple cancers. However, the function of miR‑336 in osteosarcoma (OS) remains unknown. The experimental procedures used in the present study included flow cytometry, reverse transcription‑quantitative polymerase chain reaction, luciferase reporter assay, invasion assay, western blot analysis and in vivo implantation. The results of the present study demonstrated that miR‑336 may serve as a tumor suppressor in OS. Downregulation of miR‑336 was observed in human OS specimens as well as OS cell lines. In addition, a significant negative correlation between sex determining region Y‑box 2 (Sox‑2) expression and miR‑336 was demonstrated. miR‑336 was confirmed to target the 3'‑untranslated region of Sox‑2 to inhibit proliferation, migration and invasion of OS cells. Consistently, restoration of Sox‑2 expression counteracted the effect of miR‑336, and recovered the tumorigenic potential of OS cells. The present study established a novel association between miR‑336 and Sox‑2 in OS. This relationship between miR‑336 and Sox‑2 may lead to improved knowledge concerning OS progression and sheds light on potential novel therapeutic interventions for OS treatment. [ABSTRACT FROM AUTHOR]

A full understanding of the mechanisms behind spinal cord injury (SCI) processes requires reliablethree-dimensional (3D) imaging tools for a thorough analysis of changes in angiospatial architecture. We aimed to use synchrotron radiation μCT (SRμCT) to characterize 3Dtemporal-spatialchanges in microvasculature post-SCI.Morphometricalmeasurements revealed a significant decrease invascular volume fraction, vascular bifurcation density, vascular segment density, and vascular connectivity density 1 day post-injury, followed by a gradual increase at 3, 7, and 14 days. At 1 daypost-injury, SRμCT revealed an increase in vascular tortuosity (VT), which reached a plateau after 7 days and decreased slightly during the healing process. In addition, SRμCT imagesshowed that vessels were largely concentrated in the gray matter 1 day post-injury. The maximalendothelial cell proliferation rate was detected at 7 days post-injury. The 3Dmorphology of the cavity appears in the spinal cord at 28 days post-injury. We describe a methodology for 3D analysis of vascular repair in SCI and reveal that endogenous revascularization occurs during the healingprocess. The spinal cord microvasculature configuration undergoes 3D remodeling andmodification duringthe post-injury repair process. Examination of these processesmight contribute to a full understandingof the compensatory vascular mechanisms after injury and aid in the development of novel and effective treatment for SCI. [ABSTRACT FROM AUTHOR]

Study Design: The micro-computed tomography (micro-CT) was applied to assess the effect of tetramethylpyrazine (TMP) on experimental spinal cord injury (SCI).Objective: The aim of the study was to explore the therapeutic effect of TMP on a rat SCI model using micro-CT.Summary Of Background Data: SCI is a devastating event and always accompanied by severe vascular injury. Promoting angiogenesis after SCI has recently been recognized as a potential way to enhance the neurological function recovery. How the TMP promotes angiogenesis and improved locomotor function recovery after SCI has, however, not been fully clarified. In this study, we used micro-CT to evaluate the effect on the microvasculature changes after TMP treatment.Methods: The contusion SCI model was induced in rats by a modified Allen's impact method. In the TMP treatment group, rats were injected intraperitoneally with TMP. The control group was treated with saline. Hindlimb motor function was evaluated using the Basso, Beattie, Bresnahan score. Histology was employed to examine the pathological changes and quantified at 28 days after injury. Spinal cord vessel network and angiogenesis were assessed using micro-CT.Results: Angiogenesis was increased in groups treated with TMP compared with rat in the control groups (P < 0.05). Micro-CT vividly depicted the three-dimensional morphology changes of the spinal cord microvasculature after injury and demonstrated more vessels number, vessel volume fraction, and vessel connectivity value in the groups treated with TMP than in the control groups (P < 0.05). In addition, the injury-induced lesion area in TMP group was attenuated in comparison with control groups. Similarly, neurological functions were greatly improved in groups treated with TMP compared with rats in the control groups.Conclusion: Micro-CT is useful for detecting angiogenesis after SCI. TMP therapy reduced the neuronal loss, promoted angiogenesis, and exerted a positive effect on neurological function recovery after SCI.Level Of Evidence: N/A. [ABSTRACT FROM AUTHOR]

Lung epithelial cell apoptosis is an important feature of hyperoxia-induced lung injury. The death receptor-associated extrinsic pathway and mitochondria-associated intrinsic pathway both mediate the development of lung epithelial cell apoptosis. Despite decades of research, molecular mechanisms of hyperoxia-induced epithelial cell apoptosis remain incompletely understood. Here, we report a novel regulatory paradigm in response to hyperoxia-associated oxidative stress. Hyperoxia markedly upregulated microRNA (miR)-15a/16 levels in lung epithelial cells, bronchoalveolar lavage fluid (BALF) and lung tissue. This effect was mediated by hyperoxia-induced reactive oxygen species. Functionally, miR-15a/16 inhibitors induced caspase-3-mediated lung epithelial cell apoptosis, in the presence of hyperoxia. MiR-15a/16 inhibitors robustly enhanced FADD level and downregulated Bcl-2 expression. Consistently, cleaved caspase-8 and -9 were highly induced in the miR-15a/16-deficient cells, after hyperoxia. Using airway epithelial cell-specific, miR-15a/16-/- mice, we found that Bcl-2 was significantly reduced in lung epithelial cells in vivo after hyperoxia. In contrast, caspase-3, caspase-8 and Bcl-2-associated death promoter (BAD) were highly elevated in the miR-15a/16-/- epithelial cells in vivo. Interestingly, in lung epithelial malignant cells, rather than benign cells, deletion of miR-15a/16 prevented apoptosis. Furthermore, deletion of miR-15a/16 in macrophages also prohibited apoptosis, which is the opposite of what we have found in normal lung epithelial cells. Taken together, our data suggested that miR-15a/16 may exert differential roles in different cell types. MiR-15a/16 deficiency results in lung epithelial cell apoptosis in response to hyperoxia, via modulating both intrinsic and extrinsic apoptosis pathways. [ABSTRACT FROM AUTHOR]

Background: Aptamers have emerged as excellent molecular probes for cancer diagnosis and therapy. The aim of the current study was to determine the feasibility of using DNA aptamer cy-apt 20 developed by live cell-SELEX for detecting and targeting gastric cancer. Methods: The specificity, sensitivity and biostability of cy-apt 20 in detecting gastric cancer were assessed by binding assay, cell fluorescence imaging, and in vivo tumor imaging in animal model in comparison with non-gastric cancers. Results: Flow cytometric analysis showed that cy-apt 20 had higher than 78% of maximal binding rate to gastric cancer cells, much higher than that of non-gastric cancer cells. Cell fluorescence imaging and in vivo tumor imaging showed that the targeting recognition could be visualized by using minimal dose of fluorochrome labeled cy-apt 20. Meanwhile, strong fluorescence signals were detected and lasted for a period of time longer than 50 min in vitro and 240 min in vivo. The fluorescence intensities of gastric cancer were about seven folds in vitro and five folds of that of non-gastric cancers in vivo. Conclusion: Our study demonstrated that cy-apt 20 was an excellent molecular probe with high specificity and sensitivity and a certain degree of biostability for molecular recognition and targeting therapy of gastric cancer. [ABSTRACT FROM AUTHOR]

Background: Few studies have addressed the biological features of medullary breast carcinoma (MBC) in the context of clinical outcomes. We sought to compare the baseline demographics, standard pathologic factors and long-term clinical outcomes between MBC and infiltrating ductal carcinoma-not otherwise specified (IDC-NOS) using a large database. Methods: A total of 2,202 cases with pure IDC-NOS and 188 cases with typical MBC meeting the inclusion criteria were identified. The clinical and biological features, the overall survival (OS) and recurrence/metastasis-free survival (RFS) were compared for both groups. Results: There were a higher proportion of patients diagnosed prior to 40 years of age in the MBC group compared to the IDC-NOS group. MBC cases demonstrated less aggressive tumor features such as lower tumor stage, smaller tumor size and a lower proportion of nodal involvement than IDC-NOS; however, immunohistochemical staining revealed that MBC displayed the triple-negative phenotype more often than IDC-NOS cases (40.4% versus 26.2%; P <0.001). Although the clinical behavior of MBC was not commensurate with its pathologic features, women diagnosed with MBC had a lower frequency of recurrence/metastasis (P = 0.032) and death (P = 0.042) than those with IDC-NOS, and the 10-year OS and RFS were significantly higher for MBC (91% and 74%) compared to IDC-NOS (81% and 64%). Moreover, multivariate analysis revealed that TNM stage was a statistically significant factor for survival. Conclusions: MBC in Chinese women demonstrated less aggressive behavior and better prognosis than IDC-NOS. This favorable outcome was maintained after 10 years. [ABSTRACT FROM AUTHOR]

This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman interface condition in order to improve the efficiency of the finite element method. The physical interface conditions are directly utilized to construct the boundary conditions on the interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method. [ABSTRACT FROM AUTHOR]

Ohio is an eastern USA state that historically was >70% covered in upland and mixed coniferous forest; about 60% of it glaciated by the Wisconsinan glacial episode. Its stonefly fauna has been studied in piecemeal fashion until now. The assemblage of Ohio stoneflies was assessed from over 4,000 records accumulated from 18 institutions, new collections, and trusted literature sources. Species richness totaled 102 with estimators Chao2 and ICE Mean predicting 105.6 and 106.4, respectively. Singletons and doubletons totaled 18 species. All North American families were represented with Perlidae accounted for the highest number of species at 34. The family Peltoperlidae contributed a single species. Most species had univoltine-fast life cycles with the vast majority emerging in summer, although there was a significant component of winter stoneflies. Nine United States Geological Survey hierarchical drainage units level 6 (HUC6) were used to stratify specimen data. Species richness was significantly related to the number of unique HUC6 locations, but there was no relationship with HUC6 drainage area. A nonparametric multidimensional scaling analysis found that larger HUC6s in the western part of the state had similar assemblages with lower species richness that were found to align with more savanna and wetland habitat. Other drainages having richer assemblages were aligned with upland deciduous and mixed coniferous forests of the east and south where slopes were higher. The Ohio assemblage was most similar to the well-studied fauna of Indiana (88 spp.) and Kentucky (108 spp.), two neighboring states. Many rare species and several high quality stream reaches should be considered for greater protection. [ABSTRACT FROM AUTHOR]

Background: We sought to compare the baseline demographics, standard pathologic factors and long-term clinical outcomes between ILC and infiltrating ductal carcinoma (IDC) using a large database. Methods: Clinicopathologic features, overall survival (OS), and recurrence/metastasis-free survival (RFS) were compared between 2,202 patients with IDC and 215 patients with ILC. Results: ILC was significantly more likely to be associated with a favorable phenotype, but the incidence of contralateral breast cancer was higher for ILC patients than for IDC patients (8.4% vs. 3.9%; P =0.001). The frequencies of recurrence/metastasis (P = 0.980) and death (P = 0.064) were similar among patients with IDC and patients with ILC after adjustment for tumor size and nodal status. The median follow-up was 42.8 months. Conclusions: Chinese women with ILCs do not have better clinical outcomes than their counterparts with IDC. Management decisions should be based on individual patient and tumor biologic characteristics, and not on lobular histology. [ABSTRACT FROM AUTHOR]

A neutral ferrocene-appended aryl triazole receptor 1for phosphate anions has been synthesized and characterized by X-ray crystal analysis. Among various anions, 1shows a distinct electrochemical recognition of phosphate anions by its multiple H-bonding (C–H···O) with a tetrahedral anion, which is supported by density functional theory based theoretical calculation and 1H NMR titration results. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon nanotubes (CNx)/carbon nanotube intramolecular junctions were prepared by a simple continuous chemical vapour deposition (CVD) method at 650°C. The catalyst was obtained by calcination of a layered double hydroxide precursor containing Fe and Mg. By switching between hexane and ethylenediamine repeatedly in the CVD process, multiple intramolecular junctions composed of CNx with a bamboo-like structure and empty hollow carbon nanotubes were observed, and such different structures at both sides of the junctions indicated some interesting properties and offered potential applications for future nanodevices. [ABSTRACT FROM AUTHOR]

Two new cone- and 1,3-alternate-calix[4]arenes (cone-1 and 1,3-alt-1), bearing four modified TTF (tetrathiafulvalene) substituents on the upper rim, have been synthesized. The binding ability of these two sets of conformers for various anions, including F-, Cl-, Br-, I-, PF6-, ClO4-, HSO4-, CH3COO-, H2PO4-, and HP2O73-, was tested in organic media by monitoring the changes in their UV/vis and 1H NMR spectra as a function of added anion, as well as via cyclovoltammetry (CV) (all anions studied as their respective TBA salts). On the basis of the present findings, we propose that incorporation of four TTF units within an overall calix[4]arene-based recognition framework produces a preorganized receptor system that displays a modest preference for the pyrophosphate (HP2O73-) anion. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence indicates that eosinophils contribute greatly to airway remodeling in asthma. Since interleukin-5 (IL-5) plays a critical role in the regulation of eosinophils in asthma, anti-IL-5 therapy may be a novel approach to inhibit airway remodeling in asthma. Objectives: In this study, we applied a recombinant adeno-associated virus vector-mediated antisense IL-5 gene delivery (rAAV-ASIL-5) system to investigate its effect on airway remodeling in ovalbumin (OVA)-sensitized and -challenged rats. Methods: rAAV-ASIL-5 was used to infect OVA-sensitized and -challenged rats. IL-5 protein in bronchoalveolar lavage fluid (BALF) was detected by ELISA. The eosinophils in BALF were counted. Transforming growth factor (TGF)-β1- and TGF-β2-positive cells in the peribronchial space were detected by immunohistochemical staining. Lung tissue was collected for Sirius red staining and histological analysis. Results: rAAV-ASIL-5 significantly decreased the level of IL-5 protein, the number of eosinophils in BALF and the numbers of TGF-β1- and TGF-β2-positive cells in the peribronchial space. The area of Sirius red staining in airways was also decreased. Moreover, the rAAV-ASIL-5 treatment inhibited the increase in total bronchial wall area and airway smooth muscle area. Conclusion: These results suggest that rAAV-ASIL-5-based gene therapy could be used to inhibit airway remodeling in allergic rats. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The two most important tasks in information extraction from the Web are webpage structure understanding and natural language sentences processing. However, little work has been done toward an integrated statistical model for understanding webpage structures and processing natural language sentences within the HTML elements. Our recent work on webpage understanding introduces a joint model of Hierarchical Conditional Random Fields (HCRFs) and extended Semi-Markov Conditional Random Fields (Semi-CRFs) to leverage the page structure understanding results in free text segmentation and labeling. In this top-down integration model, the decision of the HCRF model could guide the decision making of the Semi-CRF model. However, the drawback of the top-down integration strategy is also apparent, i.e., the decision of the Semi-CRF model could not be used by the HCRF model to guide its decision making. This paper proposed a novel framework called WebNLP, which enables bidirectional integration of page structure understanding and text understanding in an iterative manner. We have applied the proposed framework to local business entity extraction and Chinese person and organization name extraction. Experiments show that the WebNLP framework achieved significantly better performance than existing methods. [ABSTRACT FROM AUTHOR]

1. The statistical rigour and interpretability of ecological assessments is strongly affected by how well we predict the biological assemblages expected to occur in the absence of human-caused stress, i.e. the reference condition. In this study, we examined how the specific method used to predict the reference condition affected the performance of two commonly used types of ecological index: RIVPACS-based O/E indices and multimetric indices (MMIs). 2. These two types of index have generally relied on different approaches to predicting the reference condition. For MMIs, some type of regionalisation is typically used to describe the range of metric values among reference sites and hence the expected range at assessed sites. For O/E indices, continuous modelling is used to predict how the biota varies among sites both among and within regions. Because the prediction method differs for these two types of index, it has been impossible to judge if differences in index performance (accuracy, precision, responsiveness and sensitivity) are caused by differences in the way reference condition biota are predicted or by differences in what the indices measure. 3. We used a common data set of 94 reference sites and 255 managed sites and the same potential set of predictor variables to compare the performance of five different MMIs and three O/E indices that were derived from different prediction methods: null models, multiple linear regression (MLR), classification and regression trees, Random Forests (RF) and linear discriminant functions models (LDM). We then calculated values of these indices for samples collected from the managed catchments as well as samples collected from 13 reference sites that were progressively altered in known ways by a simulation programme. 4. Both the type of predictor used and the type of index affected overall index performance. Modelled indices generally had the greatest sensitivity in assessing managed sites as biologically different from reference. Index sensitivity was determined by both an aspect of index precision (10th percentile of reference condition values) and responsiveness. The O/E indices showed the best scope of response to known biological alteration. All three O/E indices decreased linearly in response to simulated alteration in both overall assemblage structure (Bray-Curtis dissimilarity) and taxa loss. The MMIs declined linearly from low to intermediate levels of assemblage alteration but were less responsive between intermediate and high levels of biological alteration. 5. Insights gained from simulations can aid in testing assumptions regarding index response to stress and help ensure that we select indices that are ecologically interpretable and most useful to resource managers. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the specific antitumor responses against autologous hepatocellular carcinoma (HCC) cells of dendritic cells (DCs) fused with allogeneic HCC cell line, and evaluated the feasibility of BEL7402 as an alternative strategy to deliver shared HCC antigens to DCs. Methods: Previous studies demonstrated fusions of patient-derived DCs and autologous tumor cells could induce T-cell responses against autologous tumors. These fusion cells require patient-derived tumor cells, which are not, however, always available. Here, we report the fusing of autologous DCs with allogeneic HCC cell line to induced cytotoxic T-lymphocyte (CTL) response against autologous HCC cells compare with autologous tumor cells. Results: These DC/ BEL7402 fusion cells co-expressed tumor-associated antigens and DC-derived costimulatory and major histocompatibility complex molecules. Both CD4+ and CD8 T+ cells were activated by the fusion cells as demonstrated by the proliferation of T-cells, the production of cytokines and the simultaneous induction of specific CTL responses. Significantly, CTL induced by dendritic cell/allogeneic BEL7402 fusion cells were able to kill autologous HCC cells by human leukocyte antigen-A2 restricted mechanisms. The results did not show significant difference between DC fusion with autologous hepatocellular carcinoma cells and DC fusion with allogeneic hepatocellular carcinoma cell line. Conclusions: The fusion of allogeneic HCC cell line and autologous DCs may have applications in antitumor immunotherapy through cross-priming against shared tumor antigens and may provide a platform for adoptive immunotherapy. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon nanotubes (CNx) were synthesized by the catalytic chemical vapour deposition of ethylenediamine with layered double hydroxides (LDHs) containing iron, cobalt or nickel as catalyst precursors at 650 °C. The catalytically active metal particles were obtained by calcination of LDHs followed by reduction. X-ray diffraction was used to characterize the structures of the precursors and their calcined products. Transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy were used to characterize the grown CNx. The results show that the CNx grown with Mg2Fe-LDH as catalyst precursor have a bamboo-like morphology and large diameter, while hollow tubes are obtained with CoMgAl- and NiMgAl-LDH as catalyst precursors. The CNx grown with CoMgAl-LDH have the highest N-doped content and the CNx grown with NiMgAl-LDH have the highest degree of graphitization among these three products. [ABSTRACT FROM AUTHOR]

The authors report their experience on one patient with hypersexuality from resection of left occipital arteriovenous malformation. To the best of our knowledge, this is the first case reported in the literature. A 35-year-old right-handed female farmer suffered a sudden left occipital hemorrhage with subarachnoid and subdural hemorrhages of the left hemisphere. Transient left uncal herniation occurred at the onset and was released by conservative treatment. Digital subtraction angiography showed a brain left occipital arteriovenous malformation. After microsurgical resection of the arteriovenous malformation, the patient developed hypersexual behavior. Positron emission tomography showed hypermetabolism in the left frontal region and left posterior hippocampal gyrus and hypometabolism in the left anterior hippocampal gyrus and the left occipital surgical area. Theories concerning normal pressure perfusion breakthrough and specific areas in the brain responsible for the human sexual response are discussed. [ABSTRACT FROM AUTHOR]

Background and objective: The accumulation of eosinophils in airways is an important characteristic of asthma. The process is primarily mediated by interleukin-5 (IL-5) secreted by Th2 lymphocytes. This study explored a new approach to asthma therapy in which allergic rats were transfected with the IL-5 antisense gene delivered by the recombinant adeno-associated virus (rAAV-ASIL-5). Methods: The viral vector rAAV-ASIL-5 was constructed and the IL-5 antisense gene transfected into allergic rats. The levels of IL-5, IgE, eotaxin and eosinophilic cationic protein (ECP) in sera and bronchoalveolar lavage fluid (BALF) were measured by ELISA. The inflammatory responses in lung tissues were evaluated by histological study. Results: The levels of IL-5 protein in serum and BALF were significantly decreased in the allergic rats treated with rAAV-ASIL-5 ( P < 0.05). Serum ovalbumin-specific IgE was reduced in treated rats compared with untreated rats ( P < 0.05). rAAV-ASIL-5 treatment also reduced eosinophils in the peripheral blood and BALF, as well as the ECP and eotaxin levels in serum and BALF ( P < 0.05). There was significantly less inflammation in the lungs of rAAV-ASIL-5-treated rats than in those of untreated rats. No obvious pathological damage to the kidneys and livers of the rats treated with rAAV was observed. Conclusions: Treatment with rAAV-ASIL-5 inhibited the accumulation of eosinophils and airway inflammation in the rat model of allergic asthma by suppressing IL-5 production. These results suggest that rAAV-ASIL-5-based gene therapy may be used for the treatment of allergic asthma. [ABSTRACT FROM AUTHOR]

Solar cells are one attractive method for harnessing inexhaustible clean energy from the sun. Organic photovoltaic technology is emerging as a potential competitor to silicon-based photovoltaic cells (PVCs), and their power conversion efficiencies (PCE) can now exceed 6%. Polymeric bulk-heterojunction (BHJ) PVCs, whose photoactive layer is composed of a blend of bicontinuous and interpenetrating donors and acceptors, can maximize interfacial area between the donor and the acceptor. [ABSTRACT FROM AUTHOR]

Stoneflies are imperiled in many regions of the world, but it is often difficult to determine their relative imperilment because of the absence of reliable data. Natural history collections, such as those at the Illinois Natural History Survey (INHS), are sources for such data. We have used Random Forests models of the historical distributions of Illinois stoneflies to better understand their natural range. We have also determined which of 58 georeferenced reach, watershed, and climate summary data appear to explain these distributions. Four species were modelled with relative success, suggesting that this approach has merit and that it may be useful for determining the extent of loss and to informing future conservation efforts for Plecoptera in Illinois and surrounding areas. Expanding the range of this analysis to include adjacent states will improve the models and allow us to model rare species for which enough data were not present from Illinois alone. [ABSTRACT FROM AUTHOR]

The nitrogen (N)-doped carbon (CNx) nanotubes were synthesized by pyrolysis of ethylenediamine with Ni1.07Mg1.01AlO3.58, Ni1.99Mg0.29AlO3.78, and Ni2.31Mg0.08AlO3.89 mixed oxides as catalysts at 650°C. Those mixed oxides were obtained by calcination of corresponding layered double hydroxide precursors (LDHs). Structure and composition of LDHs and mixed oxides were characterized by X-ray diffraction (XRD) and Inductively coupled plasma spectrum. X-ray photoelectron spectroscopy and transmiβion electron microscope were used to characterize the N content, proportion of pyridine-like N structure and morphology of CNx nanotubes. The results showed that the tubes grown with Ni2.31Mg0.08AlO3.89 as catalysts had more obvious bamboo-like structure, larger diameter than those grown with Ni1.07Mg1.01AlO3.58 and Ni1.99Mg0.29AlO3.78. The N content and proportion of graphitic-like N structures increased with the content of Ni2+ increasing in LDH precursors. The morphology, N content and pyridine-like N structures for CNx nanotubes can be controlled to a certain extent by varying the content of Ni2+ in LDH precursors. [ABSTRACT FROM AUTHOR]

Recent years have witnessed the rapid growth of video games in China. This study traces their development and then investigates them using some perspectives drawn from cultural studies and political economy. It is argued that globalization and cultural proximity play different roles in two distinct markets: single PC games and online games. This study suggests China has a fast-moving home-grown game industry dominated by non-state players, and that the state assumes various roles to cope with this new social phenomenon, which is also a billion dollar business. The state monitors and regulates the market, facilitating a domestic game industry, and incorporating video games into its own nation-building agenda. The study concludes by noting two trends: (1) China potentially shifts from simply being a market for foreign games to become a center of online game exports in the regional geo-cultural market; (2) Chinese online game giants attempt to expand into domestic traditional media sectors, but may collide with the authoritarian state. [ABSTRACT FROM AUTHOR]

Environment-friendly composites reinforced with bagasse fiber (BF), a kind of natural fiber as the remains from squeezed sugarcane, were fabricated by injection molding and press molding. As appropriate matrices for injection molding and press molding, polypropylene (PP) and polycaprolactone-cornstarch (PCL-C) were selected, as a typical recyclable resin and biodegradable resin, respectively. The mechanical properties of BF/PP composites were investigated in view of fiber mass fraction and injection molding conditions. And the mechanical properties and the biodegradation of BF/PCL composites were also evaluated. In the case of injection molding, the flexural modulus increased with an increase in fiber mass fraction, and the mechanical properties decreased with an increase in cylinder temperature due to the thermal degradation of BF. The optimum conditions increasing the flexural properties and the impact strength were 90°C mold temperature, 30 s injection interval, and in the range of 165 to 185°C cylinder temperature. On the other hand, as to BF/PCL-C fully-green composites, both the flexural properties and the impact strength increased with an increase in fiber mass fraction. It is considered that the BF compressed during preparation could result in the enhancement in mechanical properties. The results of the biodegradability test showed the addition of BF caused the acceleration of weight loss, which increased further with increasing fiber content. This reveals that the addition and the quantities of BF could promote the biodegradation of fully-green composites. [ABSTRACT FROM AUTHOR]

Ecological surveys provide the basic information needed to estimate differences in species richness among assemblages. Comparable estimates of the differences in richness between assemblages require equal mean species detectabilities across assemblages. However, mean species detectabilities are often unknown, typically low, and potentially different from one assemblage to another. As a result, inferences regarding differences in species richness among assemblages can be biased. We evaluated how well three methods used to produce comparable estimates of species richness achieved equal mean species detectabilities across diverse assemblages: rarefaction, statistical estimators, and standardization of sampling effort on mean taxonomic similarity among replicate samples (MRS). We used simulated assemblages to mimic a wide range of species-occurrence distributions and species richness to compare the performance of these three methods. Inferences regarding differences in species richness based on rarefaction were highly biased when richness estimates were compared among assemblages with distinctly different species-occurrence distributions. Statistical estimators only marginally reduced this bias. Standardization on MRS yielded the most comparable estimates of differences in species richness. These findings have important implications for our understanding of species-richness patterns, inferences drawn from biological monitoring data, and planning for biodiversity conservation. [ABSTRACT FROM AUTHOR]

A parallel, three-dimensional electrostatic PIC code is developed for large-scale electric propulsion simulations using parallel supercomputers. This code uses a newly developed immersed-finite-element particle-in-cell (IFE-PIC) algorithm designed to handle complex boundary conditions accurately while maintaining the computational speed of the standard PIC code. Domain decomposition is used in both field solve and particle push to divide the computation among processors. Two simulations studies are presented to demonstrate the capability of the code. The first is a full particle simulation of near-thruster plume using real ion to electron mass ratio. The second is a high-resolution simulation of multiple ion thruster plume interactions for a realistic spacecraft using a domain enclosing the entire solar array panel. Performance benchmarks show that the IFE-PIC achieves a high parallel efficiency of &ges;90% [ABSTRACT FROM AUTHOR]

Hybrid rice has contributed greatly to the self-sufficiency of food supply in China. To meet the future demand for rice production, a national program on super rice breeding was established in China in 1996. The corresponding targets, breeding strategies and most significant advances are reviewed in this paper. New plant type models have been modified to adjust to various rice growing regions. In recognition of the importance of applying parents with intermediate subspecies differentiation in increasing F1 yield, medium type parental lines were selected from populations derived from inter-subspecies crosses with the assistance of DNA markers for subspecies differentiation. Results also indicate that a substantial increase of biomass is the basis for further enhancement of the grain yield potential, and amelioration of leaf characteristics is helpful in increasing the photosynthetic rate. Thirty-four super hybrid rice varieties have been released commercially, growing in a total area of 13.5 million hm2 and producing 6.7 thousand million kg more rice in 1998-2005. Although remarkable progress has been made in super hybrid rice breeding in China, selections on the root system and integration of more biotechnological tools remain a great challenge. [ABSTRACT FROM AUTHOR]

a new beam-based alignment (BBA) measurement system with AC k-modulation module was developed recently at Hefei Light Source (HLS), which equipped the quadrupole magnets on the storage ring with a current shunt system which was able to vary the magnet current of a given quadrupole at a given frequency. The corresponding closed orbit oscillation amplitude measured for different beam positions in the quadrupole reached a minimum when the beam was centered in the quadrupole. Amplitude estimation algorithms of software lock-in amplifier and interpolated FFT were discussed. A V-shaped curve was used to determine the offset; a method using a parabola fit to determine the offset was also discussed. This BPM-to-quadrupole offset was determined at HLS with an accuracy of ∼50 μm. The reproducibility of the beam based alignment using this technique is about 20 μm (RMS). [ABSTRACT FROM AUTHOR]

A parallel three-dimensional electrostatic Particle-In-Cell (PIC) code is developed for large-scale simulations of ion thruster plume-spacecraft interactions on parallel supercomputers. This code is based on a newly developed immersed finite-element (IFE) PIC. The IFE-PIC is designed to handle complex boundary conditions accurately while maintaining the computational speed of the standard PIC code. Domain decomposition is used in both field solve and particle push to divide the computation among processors. A high-resolution simulation of multiple ion thruster plume interactions for a realistic spacecraft using a domain enclosing the entire solar array panel is carried out to demonstrate the capability of the code. A standard finite-difference PIC (FD-PIC) code is also parallelized for comparison. Both the IFE-PIC and FD-PIC run with similar overall speed, and the IFE-PIC achieves a high parallel efficiency of ≥90%. [ABSTRACT FROM AUTHOR]

1. Biological indicators are used to measure the biological health of ecosystems. Resource managers may uncritically assume that such indicators give unbiased estimates of true biological condition, but this assumption is largely untested. Use of biased indicators could lead to ineffective and potentially damaging management. 2. We used a simulation model to compare estimated indicator values objectively with true impairment. We used the model to progressively alter the densities of 155 stream invertebrate taxa as functions of stress and taxon-specific sensitivities to stress. We applied the model to large samples collected from five reference-quality sites. After each stress event, we randomly collected 100, 300 and 600 fixed-count subsamples from the remaining assemblages and recorded the densities of all taxa in both the large sample and the fixed-count subsamples. We then examined how well two indicators, non-metric multidimensional scaling (NMDS) and sample taxa richness, detected the simulated impairment when derived from fixed-count subsamples. 3. NMDS ordinations of artificially impaired samples, and samples from reference and impaired sites, showed that the simulated impairments were realistic. NMDS further showed that impairment trajectories were evident for subsamples of 100, 300 and 600 individuals. However, the discrimination of stress levels within ordination space greatly improved with increasing sampling effort. The ordination also showed that increasing stress could cause assemblages at some sites to resemble unstressed assemblages at other sites. 4. Taxa-richness indicators were much more problematic. Estimates of taxa richness from 100- and 300-count samples often substantially underestimated true taxa loss and frequently indicated taxa gain. Apparent gains in taxa richness occurred because stress caused changes in evenness that compensated for, or even overrode, the effect of true taxa loss. Estimates of taxa loss derived from 600-count subsamples also underestimated true taxa loss, but these estimates were strongly correlated with true taxa loss. 5. Synthesis and applications. Bioassessements that rely on richness-based indicators derived from small fixed-count subsamples may substantially underestimate true biological impairment. Simulation models provide an objective means to evaluate how well different types of biotic indicators measure true biological impairment in aquatic and other types of ecosystems. [ABSTRACT FROM AUTHOR]

1. Numerous methods have been developed to sample the biota occurring in different ecosystems. However, the comparability of data derived from different sampling methods is generally unknown and is a major concern when integrating data from different studies. 2. Examination of assemblage-level attributes such as taxa richness and biotic index scores is generally inappropriate for evaluating the degree to which different sampling methods produce comparable descriptions of entire assemblages, because these measures provide no information regarding taxonomic composition. Multivariate methods are generally more appropriate for this purpose, but some of the methods previously used are not satisfactory and others have not been tested. A useful measure of sampling-method comparability (SMC) should be independent of sampling effort, independent of the sites sampled and have an explicit biological interpretation. 3. We used simulated data to compare two potential methods of assessing SMC, the R-value produced byanosim and a modified version of classification strength (CS-SMC) derived from Van Sickle's Mean Similarity Analysis. Analyses were based on similarities between the assemblages captured by two different sampling methods (electrofishing and seining) employed at the same sites. Similarities were calculated two different ways: the Bray–Curtis index and the Jaccard coefficient. 4. Based on simulated data,anosim R-values were strongly affected by sampling effort, highly variable across sites and difficult to interpret biologically. In contrast, CS-SMC values were highly stable over a range of sampling effort, across sites and easy to interpret biologically. 5. Application of CS-SMC to field data showed that seining and electrofishing produced highly comparable samples of fish in small streams: 97% comparable on average for species lists and 94% comparable for relative abundances. Kicknet and Surber samples of benthic invertebrates were also comparable after being standardised to a fixed count, but to a lesser extent than fish samples: 77% comparable on average for the taxa lists and 93% comparable for relative abundances. CS-SMC should be of general use when integrating and synthesising assemblage data from a variety of assemblages. [ABSTRACT FROM AUTHOR]

A novel approach for the synthesis of a new type of binary Ce-Ni-O mixed oxide catalysts is reported. The synthesis method involves the homogeneous gel-coprecipitation of oxalate precursor in alcoholic solution followed by calcinations in air. The results show that the as-prepared samples have high specific surface area and high component dispersion, exhibiting remarkably high activity in the catalytic combustion of methane as compared to the catalysts prepared by conventional coprecipitation techniques. It is suggested that the superior catalytic performance of the oxalate gel-coprecipitated Ce-Ni-O mixed oxide catalysts could be attributed to the generation of highly dispersed NiOx species and the creation of highly active oxygen vacancies as a consequence of an easier incorporation of Ni2+ ions into ceria lattice by the formation of solid solution in the mixed oxide samples. [ABSTRACT FROM AUTHOR]

The combination of different techniques (DR UV–vis, 51V NMR, UV-Raman, FTIR, and H2-TPR) in the characterization of vanadia supported on mesoporous SBA-15 catalysts shows that the dispersity and the nature of the vanadium species depend strongly on the V loading. In dehydrated catalysts with V contents lower than 2.8 wt%, vanadium is mainly in a tetrahedral environment. Higher V contents in the catalyst lead to the formation of polymeric V2O5-like species. Textural, SEM/TEM, and XRD results indicate that the ordered hexagonal mesoporous structure with large pore diameters of the support is retained upon the vanadium incorporation, and therefore high surface areas were obtained on the final catalysts. Vanadium species anchored to the surface show structural properties similar to those on mesoporous V-MCM and conventional V...SiO2 catalysts, but a higher surface concentration of isolated or low polymeric VOx species could be achieved on the V-SBA samples. The number and nature of the acid sites also change with the vanadium loading. The superior performance of the present mesoporous SBA-15 catalysts in the oxidative dehydrogenation of propane has been attributed to a higher dispersion of V species achieved on the SBA-15 support with large pore diameters as well as the low surface acidity of the catalyst. [Copyright &y& Elsevier]

Summary 1. Biological assemblage surveys primarily aim to characterise species composition and relative abundance at one or more spatial or temporal scales. Data interpretation and conclusions are dependent on how well samples characterise the assemblage of interest. 2. Conventional measures of data quality, e.g. standard deviations or coefficients of variation, were designed for single variable estimation, and they are either insufficient or invalid for assessing the quality of data describing entire assemblages. Similarity indices take species composition and relative abundance into account and may be used to effectively measure and control the quality of data used to characterise assemblage structure. 3. The average Jaccard coefficient (JC) calculated across multiple pairs of replicate samples, i.e. autosimilarity JC (AJC), is conceptually and numerically related to the average coefficient of variation in the densities of all species recorded, a measure of sampling precision, and to the proportion of total species richness sampled, a measure of sampling accuracy. 4. We explored how AJC can be used to assess the effect of different potential sources of error on the quality of assemblage survey data, including the sampling effort used both within regions and at individual sites, the individuals collecting samples, sub-sampling procedures, and consistency of taxon identification. 5. We found that the autosimilarity-based approach overcomes most weaknesses associated with conventional measures of data quality and can be used to effectively measure and control the quality of assemblage survey data. [ABSTRACT FROM AUTHOR]

The construction of bridges and tunnels plays an important role in the social and economic development of cities and local regions. The planning of the bridge and tunnel across Taiwan Straits will have a positive effect on the economic development at each stage: preplanning, engineering construction, and the completion of the project. The two sides of Taiwan Straits have the advantage of a suitable location, consanguineous relationship, and appropriate geographic conditions. Currently, there are many economic and cultural communications between both sides of the Straits. The bridge and tunnel from Xiamen to Jinmen can be regarded as the beginning of the "golden link belt." The total capability for sustainable development of Fujian Province ranks the sixth among 31 provinces in China, which will provide powerful support for the construction of the bridge and tunnel. Keywords bridge and tunnel; Taiwan Straits; economy of both sides of Taiwan Straits; Fujian Province. [ABSTRACT FROM AUTHOR]