Dissipation-Based Quantum Sensing of Magnons with a Superconducting Qubit.

Hybrid quantum devices expand the tools and techniques available for quantum sensing in various fields. Here, we experimentally demonstrate quantum sensing of a steady-state magnon population in a magnetostatic mode of a ferrimagnetic crystal. Dispersively coupling the magnetostatic mode to a superconducting qubit allows for the detection of magnons using Ramsey interferometry with a sensitivity on the order of 10^{-3} magnons/sqrt[Hz]. The protocol is based on dissipation as dephasing via fluctuations in the magnetostatic mode reduces the qubit coherence proportionally to the number of magnons.

Molecular topology: a useful tool for the search of new antibacterials.

Molecular topology has been applied to find new lead antibacterial compounds. Among the selected compounds, hesperidin, neohesperidin and Mordant Brown 24 stand out, with minimum inhibitory concentrations 90, MIC90 < 0.3 mg/mL.

Bone structure of the temporo-mandibular joint in the individuals aged 18-25.

Osteohistometric studies were performed in 15 female and 15 male cadavers aged 18-25. Condyloid process and right and left acetabulum of the temporo-mandibular joint have been studied. Density has been investigated using monitor screen linked with microscope (magnification 80x). Density in the spongy part of the condyloid process was 26.67-26.77%; in the subchondrial layer--72.13-72.72%, and in the acetabular wall 75.03-75.91%. Microscopic structure of the bones of the temporo-mandibular joint revealed no differences when compared with images of compact and cancellous bone shown in the histology textbooks. Sex and the side of the body had no influence on microscopic image and proportional bone density. Isles of chondrocytes in the trabeculae of the spongy structure of the condyloid process were found in 4 cases and isles of the condensed bone resembling the compact pattern in 7 cases.

New antifungals selected by molecular topology.

Molecular topology has been applied to find the new lead antimycotic compounds. Among the selected compounds stands out 3,3'-(4,4'-Biphenylene)bis(2,5-diphenyl-2H-tetrazolium chloride), Benztropine mesylate and Dicyclopentamethylenethiuram disulphide, with minimum inhibitory concentrations between 1.6 and 2 micrograms/mL.

Accumulation of a lipid-linked intermediate involved in enterobacterial common antigen synthesis in Salmonella typhimurium mutants lacking dTDP-glucose pyrophosphorylase.

The heteropolysaccharide chains of enterobacterial common antigen (ECA) are composed of linear trisaccharide repeat units having the structure----3)-alpha-Fuc4NAc-(1----4)-beta-D-ManNAcA-(1---- 4)-alpha-D-GlcNAc- (1----. Mutants of Salmonella typhimurium lacking the structural gene for dTDP-glucose pyrophosphorylase (rfbA) are severely impaired in their ability to synthesize dTDP-glucose, which is a precursor of dTDP-4-acetamido-4,6-dideoxy-D-galactose (Fuc4NAc), the donor of Fuc4NAc residues for ECA synthesis. These mutants synthesize only trace amounts of ECA, and they are hypersensitive to sodium dodecyl sulfate (SDS). Incubation of delta rfbA mutants with [3H]N-acetylglucosamine ([3H]GlcNAc) resulted in the accumulation of radioactivity in N-acetyl-D-mannosaminuronic acid (ManNAcA)-GlcNAc-pyrophosphorylundecaprenol (lipid II), the putative acceptor of Fuc4NAc residues in ECA synthesis. Lipid II did not accumulate in either wild-type cells or in rff mutants unable to synthesize ManNAcA. Both the accumulation of lipid II and the synthesis of trace amounts of ECA were abolished when delta rfbA mutants were grown in the presence of the antibiotic tunicamycin. Tunicamycin also prevented the SDS-mediated lysis of the mutants. SDS-resistant derivatives of delta rfbA mutants were isolated that were no longer able to synthesize trace amounts of ECA. Characterization of these derivatives revealed that they were defective in various steps of ECA synthesis leading to the synthesis of lipid II. The data support the conclusion that accumulation of lipid II is responsible in some way for the hypersensitivity of delta rfbA mutants to SDS.

Monoclonal antibodies to the Sp strain of infectious pancreatic necrosis virus.

Twelve hybrids secreting antibody to the Sp serotype of infectious pancreatic necrosis virus (IPNV) were isolated from the fusion of murine myeloma cells and spleen cells from mice immunized with pelleted virus. All of the monoclonal antibodies possessed the kappa (K) light chain isotype. Nine contained the mu (M), two had the gamma 2a (G2a), and one had the gamma 1 (G1) heavy chain isotype. Using an enzyme-linked immunosorbent assay (ELISA), 10 antibodies were found to be broadly reactive against partially purified representatives of the three serotypes of IPNV, the Sp, Ab, and VR-299 strains. The other two antibodies reacted with the Sp serotype alone. Characterization by immunostaining of viral polypeptides electrophoretically transferred to nitrocellulose sheets was possible only with IgG type antibodies. One of the specific monoclonal antibodies was shown to be directed against the major capsid protein while the other specific monoclonal antibody and the broadly reacting one reacted with the low molecular weight viral polypeptides.

Biosynthesis of enterobacterial common antigen.

Cultures of Salmonella typhimurium pulse-labeled with N-acetyl-D-[3H]glucosamine ([3H]GlcNAc) incorporated isotope into a GlcNAc-linked lipid that was tentatively identified as GlcNAc-pyrophosphorylundecaprenol. The incorporation of [3H]GlcNAc into this compound was abolished when cells were pulse-labeled in the presence of the antibiotic tunicamycin. Tunicamycin also abolished the in vivo synthesis of the haptenic form of enterobacterial common antigen (ECA) in S. typhimurium as determined by the passive hemagglutination test. These data indicated that the synthesis of the GlcNAc-linked lipid is related to ECA synthesis. Support for this conclusion was provided by the following observations. Cultures of Escherichia coli and S. typhimurium incorporated [3H]GlcNAc into cell envelope components that migrated as a homologous series of polymers when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The [3H]GlcNAc-labeled polymers were not detected in mutants of E. coli and S. typhimurium defective in ECA synthesis due to lesions in either the rfe or rff gene clusters. These polymers were identified as ECA based on Western blot analyses employing anti-ECA monoclonal antibody. The incorporation of [3H]GlcNAc into ECA polymers was abolished by tunicamycin when the drug was added to cultures to give a minimum concentration of 3 micrograms/ml. In addition, pulse-chase experiments provided evidence for a precursor-product relationship between the GlcNAc-linked lipid and ECA. These results strongly suggest that the GlcNAc-linked lipid is involved in the biosynthesis of ECA in a manner analogous to the role of carrier lipid in the biosynthesis of O-antigen and peptidoglycan.