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Recent listeriosis and salmonellosis outbreaks in the U.S. have been associated with consumption of specialty mushrooms, including enoki and wood ear. These mushrooms are commonly consumed in Asian dishes such as ramen noodle soup and are often used as raw garnishes. No current guidelines exist for the serving temperature of ramen broth in restaurants for safety. The objective of this study was to evaluate the inactivation of both Listeria monocytogenes and Salmonella enterica on enoki and wood ear mushrooms based on the ramen broth temperature. Fresh mushrooms were chopped into pieces, inoculated with four-strain cocktails of L. monocytogenes or S. enterica , dried at ambient conditions for 30 min, then placed into bowls. Ramen broth (i.e., pork bone broth, Tonkotsu) at initial temperatures of 60, 70, 80, 90, or 100°C was poured over the mushrooms, submerging them. The bowls were held at ambient conditions while the broth temperatures were monitored, and mushrooms were sampled at intervals up to 60 min. From the broth temperature profiles and the pathogen log reductions of each mushroom type, the non-isothermal log-linear model was used to obtain maximum inactivation rates. The maximum pathogen inactivation on both mushroom types occurred within the first 5 min, regardless of the initial broth temperature. Broth temperatures of 60 and 70°C resulted in reductions of only 1–3 log CFU/g (inactivation rates of 0.33–4.72 log CFU/g/min), while reductions of 4–5 log CFU/g (inactivation rates of 8.74–17.21 log CFU/g/min) were observed with 80°C broth. The use of 90 and 100°C broth resulted in higher reductions of >5 log CFU/g (inactivation rates of 8.56–28.08 log CFU/g/min). In all cases, surviving populations, often >2.4 log CFU/g, were observed after 60 min. The results from this study can assist in the development of guidelines on the safe serving temperature of ramen soup at restaurants. [ABSTRACT FROM AUTHOR]

40K is one of the main isotopes responsible for the radiogenic heating of the mantle in Earth-like exoplanets [1] and hence, plays a very important role in the internal geophysical dynamics of a planet. The abundance of 40K in the mantle and the core of such planets is not always possible to be determined by astrophysical observations, although constraining the nuclear reaction rates of 40K during stellar evolution can also lead to constraining the present amount of 40K in these planets, which will improve our understanding on the habitability potential of Earth-like exoplanets. This study aims to constrain the 40K(n,α)37Cl reaction rate, one of the two major destruction paths of 40K in stellar nucleosynthesis,by measuring the reverse reaction 37Cl(α,n)40K and applying the principle of detailed balance as we have done before for the 40K (40K(n,p)40Ar reaction rate) [2]. During the first set of measurements we performed differential cross-section measurements of the 37Cl(α,n1γ)40K, 37Cl(α,n2γ)40K and 37Cl(α,n3γ)40K reaction channels, for six different center of mass energies in the range between 5.1 and 5.4 MeV. The experiment took place at the Edwards Accelerator Laboratory of Ohio University. The gamma rays from the reaction channels mentioned above were detected by two LaBr3 scintillators. Using the swinger facility to change the angle of the beam-target system with respect to the detection system, we were able to take measurements for the differential cross-section at six different angles between 20° and 120° in the lab system.

Specialty mushrooms have been implicated in foodborne illness outbreaks in the U.S. in recent years. These mushrooms are available to consumers in both their fresh and dried states. Dehydrating mushrooms is a convenient way to increase shelf life. The dehydration process results in a lowered water activity (aw) of the commodity, creating an environment where both spoilage and pathogenic bacteria cannot proliferate. Prior to food preparation and consumption, these mushrooms are typically rehydrated and possibly stored for later use which could lead to increased levels of pathogens. This study examined the survival and growth of Listeria monocytogenes and Salmonella enterica on dehydrated enoki and wood ear mushrooms during rehydration and subsequent storage. Mushrooms were heat dehydrated, inoculated at 3 log CFU/g, and rehydrated at either 5 or 25°C for 2 h. Rehydrated mushrooms were stored at 5, 10, or 25°C for up to 14 d. L. monocytogenes and S. enterica survived on enoki and wood ear mushroom types during rehydration at 5 and 25°C, with populations often <2.39 log CFU/g. During subsequent storage, no growth was observed on wood ear mushrooms, regardless of the rehydration or storage temperature, with populations remaining <2.39 log CFU/g for both pathogens. When stored at 5°C, no growth was observed for either pathogen on enoki mushrooms. During storage at 10 and 25°C, pathogen growth rates and populations after 14 d were generally significantly higher on the enoki mushrooms rehydrated at 25°C; the highest growth rate (3.56 ± 0.75 log CFU/g/d) and population (9.48 ± 0.62 log CFU/g) after 14 d for either pathogen was observed by S. enterica at 25°C storage temperature. Results indicate a marked difference in pathogen survival and proliferation on the two specialty mushrooms examined in this study and highlight the need for individual product assessments. Data can be used to assist in informing guidelines for time and temperature control for the safety of rehydrated mushrooms. [ABSTRACT FROM AUTHOR]

We attempted to grow a thin film of BiN by co-deposition of bismuth and nitrogen on rock-salt structure MgO (001) substrates. Furthermore, we studied the effect of variation of the growth temperature and the nitrogen to bismuth flux ratios on sample growth. For the samples grown and conditions used, we do not find strong evidence for the formation of a bulk Bi-N alloy. Even for very high nitrogen to bismuth flux ratio, we observed only bismuth and no nitrogen using bulk Rutherford back-scattering spectroscopy measurements, and only 1%–2% nitrogen was seen through surface Auger electron spectroscopy measurements. The in-plane lattice measurements show that the resulting Bi (110) samples are strained, which is presumably caused by lattice mismatch between the sample and the substrate when grown without any buffer layer. The use of a high-temperature buffer layer helps to release strain in the sample but only along one axis. Measurements of the atomic layer spacing using x-ray diffraction and also scanning tunneling microscopy confirm the Bi (110) thin film sample structure. [ABSTRACT FROM AUTHOR]