Analysis of the Relationship of Microbial Contamination with Temperature and Cleaning Frequency and Method of Domestic Refrigerators in Japan

ABSTRACT Hygiene management of domestic refrigerators is an important aspect of food poisoning prevention. The aim of the present study was to confirm the relationship between microbial contamination and hygiene management by measuring microbial levels and investigating temperature and cleaning frequency and method of domestic refrigerators in Japan. We analyzed three internal sections (the egg compartment, bottom shelf, and vegetable drawer) of 100 domestic refrigerators in Japan. Salmonella, Listeria monocytogenes, and Yersinia enterocolitica were not found in any of the refrigerators, but coliforms and Escherichia coli were detected in more than one household, and Staphylococcus aureus was the most frequently isolated pathogen. The prevalences of these microorganisms had similar tendencies in all three sections sampled and were highest in the vegetable drawer. The temperature distribution in the refrigerators was also investigated, and a temperature >6.1°C (improper temperature) was found in 46.2% of the areas surveyed. Only 17% of the respondents cleaned their refrigerators monthly or more often, and this frequency was lower than that reported in other countries. Fifty percent of the respondents used only water to clean the refrigerator, 10% used only an alcohol or disinfecting wipe, and 8% used only a dry cloth. Although no significant correlations were found between microbial contamination and temperatures in refrigerators, correlations were found between microbial contamination and refrigerator cleaning frequency and/or method. To our knowledge, this is the first detailed survey concerning relationships between microbial contamination and hygiene management in domestic refrigerators in Japan. The data obtained can be used to promote food poisoning management in Japanese households. HIGHLIGHTS

Drying Model for “Rambak” Crackers Production Using Hybrid Greenhouse Effect Dryer with Stove Biomass and Clay Heat Exchanger

A hybrid greenhouse effect dryer was examined for small-medium cracker industries. The system consists of a main drying chamber, biomass stove, heat exchanger, and shelf. This work aims to construct heat and mass transfer model which can describe well the drying process, as well as can be used to predict the greenhouse air temperature, product temperature, and moisture evaporation during drying. Drying is conducted in the room dryer for 9 samples of crackers where each sample is ± 150 grams and is divided into 3 samples placed on the bottom shelf, 3 samples on middle shelf, and 3 samples on the top shelf. Drying is carried out from the initial moisture content of crackers ± 63‒64% to 12‒14% for the standard fries. Mathematics model was simulated in MATLAB software and was validated by comparing the analytical and experimental result. The heat transfer model could describe well the heat transfer process during drying. It was shown that the analytical and experimental results are in good agreement, with mean error range values 5.38‒20.4%.

‘Anything off the bottom shelf’: Ephemeral fairgrounds and material swag

Travelling fairgrounds embody the ephemeral. They arrive from elsewhere to occupy an everyday space, momentarily wrenching it from regular purpose and bringing in a bombardment of shimmering surfaces, magical spaces, affects, illusions, fleeting peaks of sensory excess. Utilizing historical resources, interviews with showpeople and gathered testimony, this article examines the material encounter of the British fairground through the prize, what might be considered as a making material of the ephemeral. The prize provides material reminders of the fairground when it has departed, to counterintuitively persist through time as meaningful keepsakes and souvenirs. The fairground prize is tracked as both object and concept, utilizing detailed ‘back-stage’ and ‘front-stage’ flows, Dant’s work around ‘objects in time’, spatial practices and complex crossovers to other cultural trends. Taking his research to the contemporary period, the author proposes a significant shift in the fairground prize that has a wider impact on the aesthetic engagement with the fair.

RECENT CHANGES IN PRODUCING OF THE INTERMEDIATE WATER IN THE OKHOTSK SEA AND ITS PROPERTIES

Data of long-term observations on the cold intrusions in the warm intermediate layer of the Okhotsk Sea are overviewed, considering these intrusions as fresh portions of the Intermediate water of local origin. They are formed in the process of the high-density Bottom Shelf water cascading from the northwestern shelf, mainly in the submarine canyon at northwestern Sakhalin. Transport of these new-formed portions is traced in the flows of cyclonic circulation of the Okhotsk Sea waters from the area of their origin to the southern Kuril Straits, that takes from 2 to 6 years. Similar intrusions are found in the Pacific, mainly at southern Kuril Islands, where they penetrate presumably through the Vries and Bussol Straits. Year-to-year variability of the Bottom Shelf water and the new-formed Intermediate water properties are analyzed in dependence on external factors. There is determined that the volume and density of the Bottom Shelf water depend on winter severity that could be quantitatively explained by the ice cover; all these parameters decrease recently. Salinity of the new-formed Intermediate water has similar changes. Besides, tidal mixing influences on its salinity, in particularly at the Kuril Straits, so the tidal 18.6-year cycle is presented in the salinity variations. On the contrary, variations of the minimal temperature in the cold-water lenses of the fresh Intermediate water of local origin do not correlate with the changes in their production because of auto-compensatory effect for temperature in the process of its cascading to different depths. The same effect is obviously applied to dissolved oxygen, that’s why the oxygen content in the upper intermediate layer at the area of cascading is rather stable and doesn’t correlate with the ice cover changes. However, ventilation of the medium and deeper parts of the intermediate layer decreases on the background of recent lowering of the Intermediate water producing, in particularly the production of the water with σq ≥ 26.8. On a distance from the area of cascading, the tendency to deoxygenizing spreads over the whole intermediate layer of the Okhotsk Sea.

Hourly Observed Internal Waves by Geostationary Ocean Color Imagery in the East/Japan Sea

As internal waves (IWs) are generated via internal tidal energy near the bottom shelf break of the Korea Strait, continuous evolutions of IWs are extremely difficult to observe using satellite observations. However, the Geostationary Ocean Color Imager (GOCI) has enabled the detection of IWs in the East/Japan Sea (EJS) on an hourly basis to investigate their propagation behavior. For an extended IW analysis, a total of seven packets were identified using GOCI chlorophyll-a concentration (Chl-a) measurements around the Ulleung Basin and Dok Island in the EJS. The results demonstrate that the IW locations had lower Chl-a values than non-IW-affected regions on 10, 11, 13, and 14 August 2013. The lower Chl-a values are due to the significant wave heights of the IWs, which cause surface water masses to be dispersed. In addition, from the continuous trajectories of the waves in the hourly GOCI Chl-a imagery, quantitative physical parameters of the IWs, such as their pathway (northeasterly), phase speed (1.46–1.61 m s−1), amplitude (20.62–26.76 m), and period (12.29 h), could be obtained. Therefore, the advantage of using GOCI is the ability to detect and analyze the physical characteristics of IWs on an hourly time scale.

Seasonal and inter-annual temperature variability in the bottom waters over the Black Sea shelf

Long-term changes in the state of the Bottom Shelf Water (BSW) on the Western shelf of the Black Sea are assessed using analysis of intra- and inter-annual variations of temperature as well as their relations to physical parameters of both shelf and deep-sea waters. First, large data sets of in-situ observations over the 20th century are compiled into high-resolution monthly climatology at different depth levels. Then, the temperature anomalies from the climatic mean are calculated and aggregated into spatial compartments and seasonal bins to reveal temporal evolution of the BSW. For the purpose of this study the BSW is defined as such shelf water body between the seabed and the upper mixed layer (bounded by the σθ = 14.2 isopycnal) which has limited ability to mix vertically with oxygen-rich surface waters during the warm season (May–November) due to the formation of a seasonal pycnocline. The effects of atmospheric processes at the surface on the BSW are hence suppressed as well as the action of the "biological pump". The vertical extent of the near- bottom waters is determined based on energy considerations and the structure of the seasonal pycnocline, whilst the horizontal extent is controlled by the shelf break, where strong along-slope currents hinder exchanges with the deep sea. The BSW is shown to occupy nearly half of the area of the shelf during the summer stratification period. The potential of the BSW to ventilate horizontally during the warm season with the deep-sea waters is assessed using isopycnic analysis of temperature variations. A long-term time series of temperature anomalies in the BSW is constructed from observations during the May–November period for the 2nd half of the 20th century. The results reveal a warm phase in the 1960s/70s, followed by cooling of the BSW during 1980–2001. The transition between the warm and cold periods coincides with a regime shift in the Black Sea ecosystem. While it was confirmed that the memory of winter convection events is well preserved over the following months in the deep sea, the signal of winter cooling in the Bottom Shelf Waters significantly reduces during the warm season. The time series of temperature in the BSW is highly correlated with the temperature of Cold Intermediate Waters in the deep sea thus indicating that the isopycnal exchanges with the deep sea are more important for inter-annual/inter-decadal variability of the BSW on the Western Black Sea shelf than winter convection on the shelf itself.