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High sensitivity in quantum sensing comes often at the expense of other figures of merit, usually resulting in distortion. Here, the authors propose a protocol with good sensitivity, readout linearity and high frequency resolution, and benchmark it through signal measurements at audio bands with NV centers.

The spatial distribution of the hydrogen atom density was evaluated in a spherical tokamak (ST) plasma sustained only with 28 GHz electron cyclotron heating (ECH). The radially resolved Hδ emissivity was measured using multiple viewing chord spectroscopy and Abel inversion. A collisional-radiative (CR) model analysis of the emissivity resulted in a ground-state hydrogen atom density of 1015–1016 m−3 and an ionization degree of 1–0.85 in the plasma.

On the basis of the results outlined in our previous report, bacterial sialyltransferases (ST) from marine sources were further characterized using glycosphingolipids (GSL), especially ganglio-series GSLs, based on the enzymatic characteristics and kinetic parameters obtained by Line weaver-Burk plots. Among them, GA1 and GA2 were found to be good substrates for these unique STs. Thus, new gangliosides synthesized by α2-3 and α2-6STs were structurally characterized by several analytical procedures. The ganglioside generated by the catalytic activity of α2-3ST was identified as GM1b. On the other hand, when enzyme reactions by α2-6STs were performed using substrates GA2 and GA1, very unique gangliosides were generated. The structures were identified as NeuAcα2-6GalNAcβ1-4Galβ1-4Glcβ-Cer and NeuAcα2-6Galβ1-3GalNAcβ1-4Galβ1-4Glcβ-Cer, respectively. The synthesized ganglioside NeuAcα2-6GalNAcβ1-4Galβ1-4Glcβ-Cer showed binding activity to the influenza A virus {A/Panama/2007/99 (H3N2)} at a similar level to purified sialyl(α2-3)paragloboside (S2-3PG) and sialyl(α2-6)paragloboside (S2-6PG) from mammalian sources. The evidence suggests that these STs have unique features, including substrate specificities restricted not only to lacto-series but also to ganglio-series GSLs, as well as catalytic potentials for ganglioside synthesis. This evidence demonstrates that effective in vitro ganglioside synthesis could be a valuable tool for selectively synthesizing sialic acid (Sia) modifications, thereby preparing large-scale gangliosides and permitting the exploration of unknown functions.

The peroidicity of motor disassembly for maintenance is currently determined by the durability of the sealed grease they contain. The lifetime of this grease is the shortest of all the motor's bearing parts and materials, and therefore needs to be made longer. For this purpose, therefore, the authors discussed the shape of the grease pocket, and concluded that the efficiency of lubrication depends on the shape of the pocket and the relative position between pockets and the bearing, which should be appropriately modified. In this report, the authors performed laboratory testing with full-scale grease pocket models of refined and conventional shapes to compare the service lives and determine the effects of improvement.

Nitrogen-vacancy (NV) defect centers in diamond are promising solid-state magnetometers. Single centers allow for high-spatial-resolution field imaging but are limited in their magnetic field sensitivity. Using defect-center ensembles, sensitivity can be scaled with sqrt[N] when N is the number of defects. In the present work, we use an ensemble of N∼10^{11} defect centers within an effective sensor volume of 8.5×10^{-4} mm^{3} for sensing at room temperature. By carefully eliminating noise sources and using high-quality diamonds with large NV concentrations, we demonstrate, for such sensors, a sensitivity scaling as 1/sqrt[t], where t is the total measurement time. The associated photon-shot-noise-limited magnetic-field sensitivity for ac signals of f=20 kHz is 0.9 pT/sqrt[Hz]. For a total measurement time of 100 s, we reach a standard deviation of about 100 fT. Further improvements using decoupling sequences and material optimization could lead to fT/sqrt[Hz] sensitivity.

The aims of this study were to identify fungal growth inhibitory substances in cheese prepared using crude enzymes from Hericium erinaceum MAFF 435060 exhibiting milk-clotting activity and elucidate the conditions under which these substances are produced. Fungal growth inhibition caused by fatty acids, such as butanoic, hexanoic, octanoic, decanoic, and 9-decenoic acids, released by lipase activity of crude enzymes during ripening was estimated. Notably, the amounts of butanoic, hexanoic, and octanoic acids in ripened cheese exceeded their minimum growth inhibitory concentrations for Aspergillus niger NBRC 105649. Growth inhibition and high fatty acid content were observed in cheese prepared using homogenized milk as raw material, although homogenized milk in which milk fat was not encapsulated within the globule membrane was required. These results suggested that the use of crude enzymes from H. erinaceum MAFF 435060 may allow the production of cheese with a prolonged shelf life. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the crude enzyme from Hericium erinaceum (H. erinaceum) as a substitute source of rennet and assess its proteolytic behavior on bovine caseins. The crude enzyme from H. erinaceum was active in the pH range from 3.7 to 6.5 and was inactivated completely by heating at 45 °C for 15 min. The use of specific inhibitors revealed that the crude enzyme from H. erinaceum contains an aspartic protease with an optimum temperature of 30-35 °C. The addition of CaCl2 enhanced the milk-clotting activity of the enzyme. A comparison of SDS-PAGE and kinetic properties of the crude enzyme from H. erinaceum with chymosin on bovine caseins showed that as- and p-caseins were preferentially degraded relative to K-casein. The results indicate that crude enzyme from H. erinaceum can be used as an effective coagulant in cheesemaking. [ABSTRACT FROM AUTHOR]

Eleven mycelial strains of the genus Hericium were isolated to investigate the variability in milk-clotting activity and ability to coagulate ultra-high-temperature pasteurized milk (UHT-milk) of their crude enzymes. As well, the antifungal activity of cheese prepared using the crude enzymes was assessed. Based on sequence analysis of ITS-5.8S ribosomal DNA, 8 strains were identified as H. erinaceus, 2 as H. abietis, and 1 as Hericium sp. Notable differences were observed among the species and within strains in terms of milk-clotting activity of the crude enzyme preparation. The UHT-milk coagulation ability was detected in 5 strains of H. erinaceus and showed no correlation with the potency of milk-clotting activity. Furthermore, all cheese samples prepared from low-temperature pasteurized milk using the crude enzymes from the 8 strains of H. erinaceus and ripened for 30 days at 13°C showed growth inhibitory activity toward Aspergillus niger NBRC 105649. Thus, the crude enzyme preparation from H. erinaceus may be useful for cheese production. [ABSTRACT FROM AUTHOR]

In order to elucidate the physiological mechanism of palmelloid formation of the unicellular green alga Chlamydomonas eugametos by chloroplatinic acid, the factors causing inhibition of the palmelloid formation were studied in various media. Chloroplatinic acid lost its palmelloid-forming effect in the presence of nitrite ion and amines having a second functional group. Nitrate, potassium, and sodium ions and monofunctional amines were without influence on the effect of chloroplatinic acid. These results indicate that the active form of platinum (IV) may undergo ligand substitution, the resulting complex being unable to cause palmelloid formation. [ABSTRACT FROM AUTHOR]