Lactic acid bacteria (LAB) play important roles in acid production and flavor formation in fermented dairy products. Lactic acid bacteria strains with distinct characteristics confer unique features ...to products. Diverse LAB have been identified in raw milk and traditional fermented milk prepared from raw milk. However, little is known about LAB in raw milk in Japan. To preserve diverse LAB as potential starters or probiotics for future use, we have isolated and identified various kinds of LAB from raw milk produced in Japan. In this study, we focused on Lactobacillus delbrueckii, one of the most important species in the dairy industry. We identified L. delbrueckii subspecies isolated from raw milk in Hokkaido, Japan, by analyzing intraspecific diversity using 4 distinct methods, hsp60 cluster analysis, multilocus sequence analysis, core-genome analysis, and whole-genome analysis based on average nucleotide identity. The subspecies distribution and a new dominant subset of L. delbrueckii from raw milk in Japan were revealed. The discovery of new strains with different genotypes is important for understanding the geographic distribution and characteristics of the bacteria and further their use as a microbial resource with the potential to express unconventional flavors and functionalities. The strains identified in this study may have practical applications in the development of fermented dairy products.
The decay of the primordial isotopes 238U, 235U, 232Th, and 40K has contributed to the terrestrial heat budget throughout the Earth's history. Hence, the individual abundance of those isotopes are ...key parameters in reconstructing contemporary Earth models. The geoneutrinos produced by the radioactive decays of uranium and thorium have been observed with the Kamioka Liquid‐Scintillator Antineutrino Detector (KamLAND). Those measurements have been improved with more than 18‐year observation time, and improvement in detector background levels mainly with an 8‐year nearly reactor‐free period, which now permit spectroscopy with geoneutrinos. Our results yield the first constraint on both uranium and thorium heat contributions. The KamLAND result is consistent with geochemical estimations based on elemental abundances of chondritic meteorites and mantle peridotites. The High‐Q model is disfavored at 99.76% C.L. and a fully radiogenic model is excluded at 5.2σ assuming a homogeneous heat producing element distribution in the mantle.
Plain Language Summary
The energy to drive the Earth's engine comes from two different sources: primordial and radiogenic. Primordial energy comes from the added heat by collisions of accreting material and less so by the energy accompanying the sinking of metal to form the core. The radioactive decays of heat producing elements (i.e., potassium, thorium, and uranium) also generate energy and some of these decaying elements produce antineutrinos (geoneutrinos). Geoneutrino measurements provide the Earth's fuel gauge for its radiogenic power supply and insights into the planet's cooling history. The measurement accuracy of the KamLAND experiment has been improved by an 18‐year long‐term observation and a reduction of the significant background generated by commercial reactors. Consequently, modern geoneutrino measurements have entered an era of distinct spectroscopic contributions coming from uranium and thorium. The KamLAND result is consistent with compositional models for the bulk silicate Earth (the crust plus the mantle) predicting low to medium radiogenic heat (10–20 TW (1012 W)) and disfavor high concentration models (30 TW). This constraint sets the best limit on the permissible radiogenic energy budget in the Earth. Geoneutrino observations now begin to make significant contributions to the understanding of fundamental driving forces powering the Earth dynamic behavior.
Key Points
Geoneutrino measurement with low reactor neutrino backgrounds improves the distinct spectroscopic contributions of U and Th
Radiogenic power in the Earth estimated from this geoneutrino measurement is consistent with a range of models and disfavors the higher power model
Identifying the Earth's mantle contribution to the total geoneutrino flux strongly depends on an accurate estimation of the crustal contribution
The design concept of the magnetic horn system for the T2K neutrino oscillation experiment is described. We proposed a three-horn system with optics similar to a conventional two-horn system, aiming ...to focus relatively low-momentum pions under a high beam intensity environment. Good focusing efficiency was obtained with compact horns and a rather large inner conductor radius for the first horn. The geometry of the decay volume was also optimized. The intensity and quality of the obtained neutrino flux is satisfactory to achieve the T2K physics goals.
We have developed a dedicated front-end electronics board for a high-pressure xenon gas time projection chamber for a neutrinoless double-beta decay search. The ionization signal is read out by ...detecting electroluminescence photons with silicon photomultipliers (SiPMs). The board reads out the signal from 56 SiPMs and records the waveforms at 5 MS/s with a wide dynamic range up to 4000 photons/200 ns. The SiPM bias voltages are provided by the board. Fine adjustment of the bias voltage for each channel is realized while keeping the dc coupling readout constant, which is indispensable for readout of microsecond-long pulses or at high rate environment. Additional analog-to-digital converters (ADCs) measure one photon-equivalent dark current for calibration and monitoring of the SiPM. The obtained performance satisfies the requirement for a neutrinoless double-beta decay search.
Previous studies have disagreed about whether prostaglandin EP 1 or EP 3 receptors are critical for producing febrile responses. We therefore injected lipopolysaccharide (LPS) at a variety doses
(1 ...μg kg â1 â1 mg kg â1 ) intraperitoneally (I.P.) into wild-type (WT) mice and mice lacking the EP 1 or the EP 3 receptors and measured changes in core temperature ( T c ) by using telemetry. In WT mice, I.P. injection of LPS at 10 μg kg â1 increased T c about 1 °C, peaking 2 h after injection. At 100 μg kg â1 , LPS increased T c , peaking 5â8 h after injection. LPS at 1 mg kg â1 decreased T c , reaching a nadir at 5â8 h after injection. In EP 1 receptor knockout (KO) mice injected with 10 μg kg â1 LPS, only the initial (< 40 min) increase in T c was lacking; with 100 μg kg â1 LPS the mice showed no febrile response. In EP 3 receptor KO mice, LPS decreased T c in a dose- and time-dependent manner. Furthermore, in EP 3 receptor KO mice subcutaneous injection of turpentine did not induce fever. Both EP 1 and EP 3 receptor KO mice showed a normal circadian cycle of T c and brief hyperthermia following psychological stress (cage-exchange stress and buddy-removal stress). The present study
suggests that both the EP 1 and the EP 3 receptors play a role in fever induced by systemic inflammation but neither EP receptor is involved in the circadian rise
in T c or psychological stress-induced hyperthermia in mice.
Rose hip is the fruit of the rose plant, which is widely used in food, cosmetics and as a traditional medicine. Therefore, rose hip is considered safe and has a sufficient history of consumption as ...food. However, few studies have reported on the safety of rose hip extracts in toxicological analyses. Thus, to evaluate the safety of rosehip polyphenol MJ (RHPMJ), an aqueous ethanol extract standardized with the trans-tiliroside content, we performed genotoxicity and 90-day repeated oral dose toxicity studies in compliance with the Organisation for Economic Co-operation and Development-Good Laboratory Practice. RHPMJ did not induce gene mutations in reverse mutation tests of Salmonella typhimurium TA98, TA100, TA1535, TA1537 and Escherichia coli WP2uvrA strains and did not induce chromosomal aberrations in cultured Chinese hamster lung (CHL/IU) cells. Moreover, micronucleus tests using rat bone marrow showed RHPMJ had no micronucleus-inducing potential. Finally, 90-day repeated oral dose toxicity studies (100–1000 mg/kg) in male and female rats showed no treatment-related toxicity in rats. These data indicate that the RHPMJ had no genotoxicity and a no-observed-adverse-effect level greater than 1000 mg/kg in rats.
PDF
