A Novel Cloud Removal Method Based on Ihot and the Cloud Trajectories for Landsat Imagery

Cloud removal is significantly needed for enhancing the further utilization of Landsat imagery, since such optical remote sensing satellite images are inevitably contaminated by clouds. Clouds dynamically affect the signal transmission due to their different shapes, heights, and distribution. Generally, pixel replacement is the only and common method used to remove thick opaque clouds, and radiometric correction techniques has been widely adopted to remove the thin clouds. However, no methods can remove both thick and thin clouds at the same time. In this paper, a new method is proposed based on fitting “trajectory” of cloudy pixels with the help of IHOT spatially charactering clouds for pixel correction, which considers signal transmission including not only the additive reflectance from the clouds but also the energy attenuation when solar radiation passes through them. The experimental results show that the proposed approach performs effective removal for thick and thin clouds, and possesses the highest accuracy with the reference image, which can restore land cover information accurately

Comparison of Efficacy of Deep Brain Stimulation of Different Targets in Parkinson's Disease: A Network Meta-Analysis

Background: Deep brain stimulation (DBS) is considered an effective treatment option for Parkinson's disease (PD). Several studies have demonstrated the efficacy of neurostimulation in patients with advanced PD. The subthalamic nucleus (STN), the internal globus pallidus (GPi), ventral intermediate nucleus (Vim), and pedunculopontine nucleus (PPN) are reportedly effective DBS targets for control of Parkinsonian tremors. However, there is no consensus on the ideal target for DBS in patients with Parkinson's disease. Only a few studies have directly compared the efficacy of DBS of the Vim, STN, and GPi. Therefore, we searched PubMed, Embase, Cochrane Library, and other databases for observational studies, extracted data on unified Parkinson's disease rating scale (UPDRS) scores and performed a comprehensive network meta-analysis of different strategies of DBS and compared the efficiency of DBS at different targets.Methods: Forest plot was used to examine the overall efficiency of DBS; cumulative probability value was used to rank the strategies under examination. A node-splitting model was employed to assess consistency of reported outcomes inconsistency. A total of 16 studies which focused on UPDRS improvement were included in the network meta-analysis.Results: By comparing the overall efficiency associated with each target, we confirmed the efficacy of DBS therapy in PD. Our findings revealed similar efficacy of DBS targeted at GPi and STN in the on-medication phase [GPi-3.9 (95% CI −7.0 to −0.96); STN-3.1 (−5.9 to −0.38)]; however, in the off-medication phase, Vim-targeted DBS was associated with better improvement in UPDRS scores and could be a choice as a DBS target for tremor-dominant Parkinsonism.Conclusions: Our findings will help improve clinical application of DBS

Association of polymicrobial interactions with dental caries development and prevention

Dental caries is a common oral disease. In many cases, disruption of the ecological balance of the oral cavity can result in the occurrence of dental caries. There are many cariogenic microbiota and factors, and their identification allows us to take corresponding prevention and control measures. With the development of microbiology, the caries-causing bacteria have evolved from the traditional single Streptococcus mutans to the discovery of oral symbiotic bacteria. Thus it is necessary to systematically organized the association of polymicrobial interactions with dental caries development. In terms of ecology, caries occurs due to an ecological imbalance of the microbiota, caused by the growth and reproduction of cariogenic microbiota due to external factors or the disruption of homeostasis by one’s own factors. To reduce the occurrence of dental caries effectively, and considering the latest scientific viewpoints, caries may be viewed from the perspective of ecology, and preventive measures can be taken; hence, this article systematically summarizes the prevention and treatment of dental caries from the aspects of ecological perspectives, in particular the ecological biofilm formation, bacterial quorum sensing, the main cariogenic microbiota, and preventive measures

Simultaneous Characterization of Lipid sn-Positional and Double-Bond Positional Isomers using On-Demand Electrochemical Mass Spectrometry

We present an on-demand electrochemical mass spectrometry workflow for lipid structural characterization with the capability of identifying double-bond and sn-positional isomers. Two voltage-controlled electrochemical reactions, interfacial electro-epoxidation and anodic corrosion of a cobalt electrode, are cascaded in this strategy. The epoxidized products and Co-adducted ions of lipids are fragmented in tandem MS to generate structure characteristic fragments that indicate double-bond and sn-positions. The unique feature of this workflow lies in the sequential localization of double bonds, elucidation of sn-positions, and collection of native lipid information in a single system and simply by tuning ESI voltages. This feature, as well as low sample consumption, no need for extra apparatus, and quantitative analysis, should allow wide applications in the lipidomic field

Interfacial Electro-Epoxidation in Electrospray Ionization Mass Spectrometry for Simultaneous Analysis of Negatively and Positively Charged Unsaturated Glycerophospholipids

In this study, we developed an AC-induced interfacial electro-epoxidation reaction for localization of double-bonds in nega-tively and positively charged forms of lipids simultaneously. An AC voltage plays multiple roles in this method, including initiation of the electrochemical epoxidation of double-bonds in both charge states of lipids, and protonation and deprotona-tion of lipid for detection in both ion modes. The advantages of simultaneous detection of negatively changed and positively charged unsaturated lipids, voltage-controlled electrochemical derivatization, and the low sample consumption allow its wide applications in a broad range of lipid-related research

Theoretical Model and Numerical Analysis of the Tip Leakage Vortex Variations of a Centrifugal Compressor

A centrifugal compressor of a micro turbine generator system is investigated by the theoretical model and numerical analysis to explore the characteristics of the tip leakage vortex as the centrifugal compressor approaches stall. The numerical simulation results show the cross-sectional shape of the tip leakage vortex is elliptical, and its long and short axes are gradually stretched as the compressor approaches stall. Moreover, the vortex trajectory is inclined to the pressure side of the adjacent blade. In addition, the Kirchhoff elliptical vortex model is introduced to analyze the flow passage constriction effect, the passage vortex squeezing effect, and the leakage flow translation effect. Results show that there is no upper limit for the flow passage constriction effect on the tip leakage vortex. Furthermore, relative to the original vortex, the minimum constriction effect depends on the axis ratio of the elliptical tip leakage vortex. The passage vortex has an expansion effect on the tip leakage vortex rather than a squeezing effect, which is limited and also depends on the axis ratio of the ellipse. However, the effect magnitude of the leakage flow depends on the scales both of the long and short axes, which also have no upper limit

Importance of Tryptophan in Transforming an Amphipathic Peptide into a Pseudomonas aeruginosa-Targeted Antimicrobial Peptide.

Here, we found that simple substitution of amino acids in the middle position of the hydrophobic face of an amphipathic peptide RI16 with tryptophan (T9W) considerably transformed into an antimicrobial peptide specifically targeting Pseudomonas aeruginosa. Minimal inhibitory concentration (MIC) results demonstrated that T9W had a strong and specifically antimicrobial activity against P. aeruginosa, including antibiotic-resistant strains, but was not active against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Staphyfococcus epidermidis. Fluorescent spectroscopic assays indicated that T9W interacted with the membrane of P. aeruginosa, depolarizing the outer and the inner membrane of bacterial cells. Salt susceptibility assay showed that T9W still maintained its strong anti-pseudomonas activity in the presence of salts at physiological concentrations, and in hemolytic and MTT assays T9W also showed no toxicity against human blood cells and macrophages. In vivo assay demonstrated that T9W also displayed no toxicity to Chinese Kun Ming (KM) mice. Furthermore, the strong antibiofilm activity was also observed with the peptide T9W, which decreased the percentage of biomass formation in a dose-dependent manner. Overall, these findings indicated that design of single-pathogen antimicrobial agents can be achieved by simple amino acid mutation in naturally occurring peptide sequences and this study suggested a model of optimization/design of anti-pseudomonas drugs in which the tryptophan residue was a conserved element

Identification of B-Cell Epitopes of HspA from Helicobacter pylori and Detection of Epitope Antibody Profiles in Naturally Infected Persons

Helicobacter pylori (H. pylori), heat-shock protein A (HspA), is a bacterial heat-shock chaperone that serves as a nickel ion scavenging protein. Ni2+ is an important co-factor required for the maturation and enzymatic activity of H. pylori urease and [NiFe] hydrogenase, both of which are key virulence factors for pathogen survival and colonization. HspA is an important target molecule for the diagnosis, treatment, and immune prevention of H. pylori. In this work, HspA was truncated into five fragments to determine the location of an antigen immunodominant peptide. A series of overlapping, truncated 11-amino-acid peptides in immunodominant peptide fragments were synthesized chemically and screened by ELISA. The immunogenicity and antigenicity of the screened epitope peptides were verified by ELISA, Western blot, and lymphocyte proliferation tests. Two novel B-cell epitopes were identified, covering amino acids 2–31 of HspA, which are HP11 (2–12; KFQPLGERVLV) and HP19 (18–28; ENKTSSGIIIP). The antiserum obtained from HP11-KLH and HP19-KLH immunized mice can bind to naive HspA in H. pylori SS2000, rHspA expressed in E. coli, and the corresponding GST fusion peptide. Among HspA seropositive persons, the seropositive rates of HP11 and HP19 were 21.4% and 33.3%, respectively. Both of the B-cell epitopes of HspA are highly conserved epitopes with good antigenicity and immunogenicity