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Extension of nuclear magnetic resonance (NMR) to nanoscale samples has been a longstanding challenge because of the insensitivity of conventional detection methods. We demonstrated the use of an individual, near-surface nitrogen-vacancy (NV) center in diamond as a sensor to detect proton NMR in an organic sample located external to the diamond. Using a combination of electron spin echoes and proton spin manipulation, we showed that the NV center senses the nanotesla field fluctuations from the protons, enabling both time-domain and spectroscopic NMR measurements on the nanometer scale.

In plants the dorsoventral boundary of leaves defines an axis of symmetry through the centre of the organ separating the top (dorsal) and bottom (ventral) tissues. Although the positioning of this boundary is critical for leaf morphogenesis, how the boundary is established and how it influences development remains unclear. Using live-imaging and perturbation experiments we show that leaf orientation, morphology and position are pre-patterned by HD-ZIPIII and KAN gene expression in the shoot, leading to a model in which dorsoventral genes coordinate to regulate plant development by localizing auxin response between their expression domains. However we also find that auxin levels feedback on dorsoventral patterning by spatially organizing HD-ZIPIII and KAN expression in the shoot periphery. By demonstrating that the regulation of these genes by auxin also governs their response to wounds, our results also provide a parsimonious explanation for the influence of wounds on leaf dorsoventrality.

Two-dimensional magnetic resonance imaging of hydrogen in organic samples with a resolution of 12 nm can be achieved by using the spin of a nitrogen–vacancy centre in diamond as a sensor. Magnetic resonance imaging, with its ability to provide three-dimensional, elementally selective imaging without radiation damage, has had a revolutionary impact in many fields, especially medicine and the neurosciences. Although challenging, its extension to the nanometre scale could provide a powerful new tool for the nanosciences, especially if it can provide a means for non-destructively visualizing the full three-dimensional morphology of complex nanostructures, including biomolecules 1 . To achieve this potential, innovative new detection strategies are required to overcome the severe sensitivity limitations of conventional inductive detection techniques 2 . One successful example is magnetic resonance force microscopy 3 , 4 , which has demonstrated three-dimensional imaging of proton NMR with resolution on the order of 10 nm, but with the requirement of operating at cryogenic temperatures 5 , 6 . Nitrogen–vacancy (NV) centres in diamond offer an alternative detection strategy for nanoscale magnetic resonance imaging that is operable at room temperature 7 . Here, we demonstrate two-dimensional imaging of 1 H NMR from a polymer test sample using a single NV centre in diamond as the sensor. The NV centre detects the oscillating magnetic field from precessing protons as the sample is scanned past the NV centre. A spatial resolution of ∼12 nm is shown, limited primarily by the scan resolution.

3D point clouds from terrestrial laser scanners (TLS) are used in a variety of fields and applications. To acquire high-quality point clouds that have enough point density, small scanning errors, and no lack of points in important regions, appropriate scan planning, including determination of scanner positions and scan conditions, is required. Currently, planning is supported by knowledge and experience of skilled workers, and it is difficult to ensure the quality of acquired point clouds. In this study, we propose a system for visualization of point clouds to support the acquisition of high-quality point clouds using TLS. The system allows the user to see and check the quality of scanned TLS point clouds and unscanned regions intuitively by superimposing the point clouds onto the real world using a mixed reality (MR) device. In addition, the system supports finding the next best scanner position for additional laser scans based on predicted scan quality visualization to acquire higher-quality points or fill the unscanned regions.

In the present work, operation characteristics of a disk-type rotating detonation engine (DRDE) with a constant chamber area were experimentally studied for various total mass flow rates and a wide variety of equivalence ratios of hydrogen–air mixtures. From the direct visualizations, the rotating detonation wave was found to propagate near the outer wall of the combustion chamber, regardless of the wave mode. For the present test conditions, single- and double-wave modes are observed, depending on the equivalence ratio of the mixture. The pressure gain was evaluated based on a one-dimensional flow model together with the chamber static pressure measured with the capillary tube average pressure technique. Although the present DRDE configuration provided a negative pressure gain for all the test conditions, it was found that the single-wave mode was superior to the double-wave mode in terms of the pressure gain.

Antimicrobial peptides have a broad spectrum of antimicrobial activities and are attracting attention as promising next-generation antibiotics against multidrug-resistant (MDR) bacteria. The all-d-enantiomer [ (KLAKLAK) ] has been reported to have antimicrobial activity against and , and to be resistant to protein degradation in bacteria because it is composed of D-enantiomer compounds. In this study, we demonstrated that modification of [ (KLAKLAK) ] by the addition of an L-cysteine residue to its N- or C- terminus markedly enhanced its antimicrobial activities against Gram-negative bacteria such as MDR , , and . The peptides [ (KLAKLAK) ] (DP), DP to which L-cysteine was added at the N-terminus C-DP, and DP to which L-cysteine was added at the C-terminus DP-C, were synthesized at >95% purity. The minimum inhibitory concentrations of peptides and antibiotics were determined by the broth microdilution method. The synergistic effects of the peptides and the antibiotics against MDR were evaluated using the checkerboard dilution method. In order to assess how these peptides affect the survival of human cells, cell viability was determined using a Cell Counting Kit-8. C-DP and DP-C enhanced the antimicrobial activities of the peptide against MDR Gram-negative bacteria, including , and . The antimicrobial activity of DP-C was greater than that of C-DP, with these peptides also having antimicrobial activity against drug-susceptible and drug-resistant overexpressing the efflux pump components. C-DP and DP-C also showed antimicrobial activity against colistin-resistant harboring , which encodes a lipid A modifying enzyme. DP-C showed synergistic antimicrobial activity against MDR when combined with colistin. The LD of DP-C against a human cell line HepG2 was six times higher than the MIC of DP-C against MDR The LD of DP-C was not altered by incubation with low-dose colistin. Attachment of an L-cysteine residue to the N- or C-terminus of [ (KLAKLAK) ] enhanced its antimicrobial activity against , , and . The combination of C-DP or DP-C and colistin had synergistic effects against MDR . In addition, DP-C and C-DP showed much stronger antimicrobial activity against MDR and than against .

BackgroundAlthough immunoglobulin A (IgA) plays a key role in regulating gut homeostasis, its role in canine inflammatory bowel disease (IBD) is unknown.HypothesisIgA expression may be altered in dogs with IBD, unlike that observed in healthy dogs and dogs with other gastrointestinal diseases.AnimalsThirty-seven dogs with IBD, 10 dogs with intestinal lymphoma, and 20 healthy dogs.MethodsProspective study. IgA and IgG concentrations in serum, feces, and duodenal samples were measured by ELISA. IgA+ cells in duodenal lamina propria and IgA+ CD21+ peripheral blood mononuclear cells (PBMCs) were examined by immunohistochemistry and flow cytometry, respectively. Duodenal expression of the IgA-inducing cytokine transforming growth factor β (TGF-β), B cell activating factor (BAFF), and a proliferation-inducing ligand (APRIL) was quantified by real-time RT-PCR.ResultsCompared to healthy dogs, dogs with IBD had significantly decreased concentrations of IgA in fecal and duodenal samples. The number of IgA+ CD21+ PBMCs and IgA+ cells in duodenal lamina propria was significantly lower in dogs with IBD than in healthy dogs or dogs with intestinal lymphoma. Duodenal BAFF and APRIL mRNA expression was significantly higher in IBD dogs than in the healthy controls. Duodenal TGF-β mRNA expression was significantly lower in dogs with IBD than in healthy dogs and dogs with intestinal lymphoma.Conclusions and Clinical ImportanceIBD dogs have decreased IgA concentrations in feces and duodenum and fewer IgA+ PBMCs, which might contribute to development of chronic enteritis in dogs with IBD.

Mammalian nuclear Dbf2-related (NDR) kinases (LATS1 and 2, NDR1 and 2) play a role in cell proliferation, apoptosis and morphological changes. These kinases are regulated by mammalian sterile 20-like kinases (MSTs) and Mps one binder (MOB) 1. Okadaic acid (OA), which activates MST2, facilitates the complex formation of MOB1, MST2 and NDR1 in HEK293FT cells. The in vitro biochemical study demonstrates the phosphorylation of MOB1 by MST2. The phosphorylated MOB1 alone is capable to partially activate NDR1 in vitro , but MST2 is also required for the full activation. The knockdown of MOB1 or MST2 abolishes the OA-induced NDR1 activation in HEK293FT cells. Among MOB1 mutants, in which each serine or threonine residue is replaced with alanine, MOB1 T74A and T181A mutants fail to activate NDR1. Thr74, but not Thr181, is phosphorylated by MST2 in vitro , although MOB1 is also phosphorylated by MST2 at other site(s). The interaction of MOB1 T74A with NDR1 is barely enhanced by OA treatment. These findings indicate that the phosphorylation of MOB1 at Thr74 by MST2 is essential to make a complex of MOB1, MST2 and NDR1, and to fully activate NDR1.

Cooling capacity and super heat temperature control for air conditioning (AC) system operation is necessary to ensure that the system operates efficiently. In this paper, multi-step-ahead prediction of AC system behaviour is presented using backpropagation neural network model as the first effort to develop the effective control strategy. Several step-ahead cooling capacity and superheat temperature performance are predicted under modulation of compressor speed and expansion valve opening. The prediction is proposed to capture the dynamic behaviour of system that can be applied in predictive control purpose. The configuration of ANN model is developed based on nonlinear autoregressive network with exogenous input (NARX) structure. Input and output data for training and validation of ANN model are generated by AC simulator. The ANN model is optimized by investigating the effect of number of neuron and time delay input on prediction accuracy. The results show that the ANN model developed in present study has good accuracy in predicting several step-ahead of cooling capacity and superheat temperature. Accordingly, this ANN model is applicable for predictive control in future study.

Effect of the particle size (d) and apparent density on the coupling of microwaves with Fe3O4 was investigated at temperatures lower than the Curie point, TC ≃ 585 °C. Two samples in the form of tablet with particle sizes of 45-75 μm (MT75) and <45 μm (MT45) and one sample in the form of powder with a particle size of <45 μm (MP45) were heated in multi-mode and maximum E- and H-field modes using a microwave generator at a frequency of 2.45 GHz. According to the results, an earlier temperature increase and also a higher temperature was achieved in the sample heated in the maximum H-filed mode. Regarding the incubation time in all samples, the particle size of Fe3O4 has no significant effect on the time required for the initial temperature increase in the presence of the H-field. In the maximum E-field mode, a shorter time was required for the temperature increase in the MT75 sample than MT45. At T≤Tc, magnetic loss and Joule loss are the dominant heating mechanisms in the presence and absence of the H-field, respectively. Magnetic loss is independent of the particle size whereas Joule loss which is influenced by electrical conductivity, affected by particle size. Therefore, above-mentioned effect of the particle size is attributed to the dominant heating mechanism. Also, some of the small particles seems to be transparent owing to a greater penetration depth (δ), ca. 80 μm at room temperature causing an earlier onset of temperature increase in sample with larger particle size, MT75. Moreover, microwave absorption in a sample with higher apparent density, MT45, was lower because of a higher electrical conductivity of sample in tablet form, MT45, than powder form, MP45.