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31.
Effect of acid presensitization to low dose gamma irradiation on Bacillus cereus in sheep/goat meat stored at refrigeration temperature was assessed. Food grade organic acids (viz. propionic, lactic and acetic acids) were used as presensitizers followed by treatment with 1, 2 and 3 kGy irradiation doses (Co(60)). Two percent acetic acid plus 3 kGy irradiation elicited most effective to lower the total viable count and B. cereus count. Combination of treatments availed to reduce the dose required for elimination of radioresistant B. cereus and also masked the irradiation odour developed due to radiolysis. The study also revealed substantial increase in shelf life of mutton after combination treatment than single treatment without any adverse effect on acceptability of meat. 相似文献
32.
S. J. Dhoble S. C. Gedam I. M. Nagpure S. V. Godbole M. K. Bhide S. V. Moharil 《Journal of Materials Science》2008,43(9):3189-3196
Ultraviolet photo-excited luminescence from Cu-doped halosulphate phosphors has been investigated. The intense emission of
the spectrum is assigned to electronic transitions 3d94s1 → 3d10 in Cu+ ions. Increase in photoluminescence (PL) peak intensity suggesting that Cu plays an important role in PL emission in the
present matrix. However, limited hosts with Cu+ as luminescence center were studied due to difficulties in incorporating it in a luminescence form. Cu-doped halosulphate
phosphors were synthesized by wet chemical method. X-ray diffraction and PL characterization of phosphors has been reported
in this article. The article discusses the luminescence of Cu+ and the simple method of incorporation in various new hosts. 相似文献
33.
34.
During development, there is a transient overproduction of axons in the corpus callosum; this overproduction of axons is due, in part, to a transient excess of neurons that send an axon through the corpus callosum. However, transient axonal branching could also contribute to the developmental overproduction of callosal axons. To investigate this possibility, we filled developing callosal axons in the Syrian hamster with the carbocyanine dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil). Light microscopic analysis showed that, indeed, developing callosal axons branch transiently in the hamster: branching was robust on postnatal day 0 (P0) and P3 (P0 = the first 24 hr after birth), less prominent on P6 and P8, and absent by P11. Immature callosal axons branched before or after crossing the midline and at all rostral-caudal and medial-lateral levels within the corpus callosum. The majority of callosal axon collaterals that were contained within individual 100-micron-thick sections were relatively short (mean = 15.1 microns) but some collaterals extended up to approximately 135 microns from the main axon trunk before passing out of the section in which they were observed. Nearly all of the collaterals emanated from the main axon trunk; higher-order collaterals were rare. Some callosal axon trunks had multiple collaterals. Branching callosal axons originated from multiple cortical areas, including area 17. Electron microscopic observations indicated that the processes designated as axon collaterals by light microscopic criteria would have been included in electron microscopic counts of developing callosal axons. Some callosal axon trunks and branches had ultrastructural features that suggested they were degenerating. In cats, developing callosal axons branch on embryonic day 57 (E57; the first 24 hr after conception = E0) and P0. Thus, it is likely that transient branching of immature callosal axons is a generalized feature of mammalian cortical development and that it contributes to the overproduction of callosal axons, albeit perhaps to varying degrees, in multiple species. 相似文献
35.
36.
A generating system having n units, where each unit is represented by a 2-state device, will have more than 2n possible states when repair facility of the system is limited, i.e. number of repair crews is less than the number of units. When the number of units failed is more than the number of repair crews available, the most recent failures queue for repairs. This paper gives a general equation to determine the number of system states under limited repair facility and an approximate technique to determine the probabilities of system states and reliability indices of the system. 相似文献
37.
Lung tumour incidence in mice treated with hydrazine sulphate 总被引:1,自引:0,他引:1
Lung tumour incidence in mice fed with hydrazine sulphate (1.1 mg/day/mouse) was studied in male and female mice of Swiss, Strong "A" and F1 cross of ICRC (female) X C3H (Jax) (male), as well as in C17 males. Swiss strain mice showed 100% lung adenocarcinomas. None of the treated mice of different strains had liver tumours. Hydrazine sulphate also induced adenocarcinomas of lung in Strong "A" and F1 cross of ICRC females X C3H (Jax) males but it produced lymphomas of lung in C17 strain. Female mice of Swiss strain and F1 hybrids showed greater susceptibility to hydrazine sulphate than the males. It was interesting to observe that protein and vitamin B deficiency in the diet shortened the tumour induction period in Swiss strain mice. 相似文献
38.
39.
Streaming video over error-prone wireless channels is a challenge as the dynamic network conditions and slow adaptation to channel degradations may affect the quality of the streamed video. Unequal error protection (UEP) can potentially address this issue by considering the importance of each video packet and its impact on the quality of reconstructed video. This paper proposes a cross-layer UEP solution for wireless video streaming over IEEE 802.11 networks. Video packets are prioritized based on the relative importance of the video packet. UEP is achieved by adapting the link layer parameters on a per-packet basis, using inherent forward error correction and adaptive modulation capabilities of the 802.11n network. Experimental results revealed that the proposed solution achieves comparable performance to the state-of-the-art methods at a lower complexity. 相似文献
40.
Sarah Davis Ohlhorst Margaret Slavin Jennifer M. Bhide Betty Bugusu 《Comprehensive Reviews in Food Science and Food Safety》2012,11(2):233-284
Executive Summary: The Micronutrient Initiative (MI) issued the Institute of Food Technologists (IFT) a project to assess the extent to which iodized salt is used in processed foods, as well as food processors’ level of knowledge on iodine nutrition. Iodine is an essential micronutrient required by the body that is found in a limited number of foods, thus many individuals require additional sources of iodine to meet their daily requirement. Without these additional sources, a range of disorders referred to as iodine deficiency disorders (IDD), including mental impairment, may become present, with over 2 billion people worldwide at risk due to insufficient iodine nutrition. IDD is especially damaging during the early stages of pregnancy and in early childhood. In their most severe form, IDD includes cretinism, stillbirth, and miscarriage, and increased infant mortality. Since 1994 the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) have recommended universal salt iodization (USI) as a safe, cost‐effective, and sustainable strategy to ensure sufficient intake of iodine by all individuals. However, USI has in practice tended to focus only on table salt and not all salt destined for human consumption. Recent trends, particularly in industrialized countries, show that individuals are consuming the majority of their salt through processed foods, in which iodized salt is generally not used, rather than through iodized table salt. Additionally, recent initiatives to encourage reduced sodium consumption have prompted many consumers to reduce their intake of iodized table salt. While these trends in sodium consumption are more frequently observed in industrialized countries, they are expanding into many developing countries where iodine deficiency is also a concern. Thus countries which focus on iodization of table salt alone may not achieve optimal iodine nutrition of their population. This report provides an overview of the 2 Phases of this project. Phase I was to conduct an environmental scan/desk review of processed food consumption patterns in 39 countries selected by MI (see Table 1 ). Phase II was to conduct an electronic survey of food processors and detailed telephone interviews with a small sample of select company representatives from 16 countries (see Table 2 ). Per the scope of work, IFT conducted a desk review to determine the types and level of processed food consumption in the 39 countries of interest, as well as to identify suppliers of the major processed foods consumed and the use of salt as an ingredient in those products. Whenever possible, IFT also gathered information on the sodium content of widely consumed processed foods and the sources of salt currently used in these products; the types of processed foods and extent to which they are consumed by different socioeconomic groups; if iodized salt was used in processed foods; and whether or not there are policies in place to influence dietary salt reduction and how these efforts are implemented. For Phase II, IFT reached out to food company representatives to determine their use of iodized salt in processed food products; their sources of salt; their awareness of iodine nutrition and salt as a fortification vehicle; and their interest in learning more about salt iodization. For the purposes of this project, processed foods are considered to be all food products that have undergone a change of character or been altered from their original form. Table 1–. Preselected countries (from MI) for Phase I of the iodized salt in processed foods project.
Table 2–. Preselected countries (from MI) for Phase II of the iodized salt in process foods project.
To complete the desk review, IFT conducted literature searches and Internet reviews for each of the 39 countries of interest from May to September 2010. IFT reached out to its members with expertise in the countries of interest and 3rd parties such as government agencies, food companies, salt suppliers, and nongovernmental organizations to gain contacts and information. The acquisition of literature or access to databases or other sources of information which are not freely available was limited. For Phase II, IFT sent an electronic survey to over 800 individuals from all 16 countries in October 2010. IFT reached out to its members and other contacts with expertise in the countries of interest, which included food companies and salt suppliers who were asked to complete the electronic survey, but also 3rd parties, such as academics, government agencies, nongovernmental organizations, and so on, who were asked to pass the survey along to their food industry contacts. Outreach included over 15 multinational food companies. The survey responses IFT received were limited; however, IFT made a substantial effort to obtain useful information for each country. IFT also used survey responses and personal e‐mail communications to locate 10 food company representatives to participate in telephone interviews to gain more detailed information. Many of the 39 countries reviewed struggle with food insecurity, thus it was generally difficult to find food consumption data for these impoverished nations, particularly data on processed food consumption. Nationwide food consumption data were helpful to better understand processed food consumption for those countries that collected it; however, developing countries often lack the resources for such a large undertaking. Smaller, published academic studies were most useful in identifying types of foods that may be available in the different locales within a country, at times including minimally processed foods. IFT found that residents in many of the developing countries typically consume minimally processed foods such as bread and cheese, but that they do not frequently consume what are considered processed foods in “Western” society (packaged, prepared foods). Although processed foods may be available, consumption often differs based on income and region in the country. The more affluent and urban areas of countries appear more able to purchase processed foods, and therefore more likely to have a higher consumption rate. A pattern of processed food consumption or lack thereof did not present itself for the various country categories assigned to the 39 countries evaluated. Whether the country has a heavy or high IDD burden or an opportunity to progress did not correlate with the consumption of processed foods in that country. IDD is present in both developed and developing countries, and countries from each of these categories may or may not have processed foods available. Some countries with the heaviest burden for IDD may also have many processed foods available such as China, while another country with high IDD does not appear to have even minimally processed foods readily available. However, the majority of the European countries and Latin American countries identified on the list do have processed foods more readily available than some other countries identified, although not all are prepared with iodized salt. Many of the developing nations reviewed have the highest prevalence for IDD, often due to the high level of food insecurity. IDD is more closely linked to food insecure populations, which are also often low‐income and rural populations, who lack access to food, including food that may have been prepared with iodized salt. Some of the developing countries have enacted legislation to combat high rates of IDD and require iodization of all salt to be consumed; however, they also often lack regulatory infrastructure and therefore lack effective methods to monitor and enforce salt iodization. For this reason, it appears that even when legislation and other efforts have been enacted, they are not comprehensively implemented. Future research needs surrounding iodine use in processed foods include the need for nationwide food consumption data and additional food science research. Nationwide food consumption data are most helpful to determine processed food consumption; however, developing countries often lack the resources for such a large undertaking. Nationwide food consumption information can also reveal sources of salt intake in the diet and help to determine vehicle(s) for iodized salt delivery. Food science research determines the amount of iodine that should be added to a product to still meet standards after food processing and time spent on a store or consumer's shelf, and to ensure that iodization does not impact the taste or other qualities of food products. Survey and telephone respondents reported potential challenges when using iodized salt in food products, including: trade barriers; increased costs; lack of resources and technical capability; lack of enforcement; instability of iodine; potential equipment and process overhauls; competing priorities; and consumer misconceptions. Salt suppliers also face challenges when iodizing salt in developing countries, as they may not have the technical capabilities, equipment, or resources to do so. The survey and telephone respondents indicate that food companies are willing to use iodized salt in food products; however, the use of iodized salt in food products may need to be mandated by law and effectively monitored as an incentive for a company to invest, and to create a level playing field in the industry. Although USI intends for all salt for human and animal consumption to be iodized (whether used in food products or not), in practice, that is not always the case. Iodized salt appears to primarily be used in food products only when required by legislation, and companies do not appear to use iodized salt in product categories that do not require it (such as beyond bread products in Australia) or for products sold in countries that do not require it. Suggested approaches to get food companies to voluntarily use iodized salt in food products include outreach and education to company nutrition departments, who would then recommend policy changes to top levels of management. Additionally, a strong educational campaign for consumers on how to address IDD through the use of iodized salt in food processing could provide an incentive for companies to meet consumer demand. In general, although most companies are open to discussing iodine nutrition in more detail, iodine nutrition is currently discussed infrequently at food companies. Most respondents appear to have a fair level of knowledge about iodine nutrition and the use of salt as a vehicle for iodine, although individuals working for different departments in a food company have differing levels of understanding. Companies did indicate that they would be open to localized educational efforts to inform select company representatives about iodine nutrition. 相似文献
Countries with heavy | Countries with high | Countries with | Latin American | European |
---|---|---|---|---|
burden for IDD | burden for IDD | opportunity to progress | countries | countries |
India | Russia | Senegal | Chile | United Kingdom |
Pakistan | Afghanistan | Ghana | Argentina | Ireland |
Ethiopia | United Republic of Tanzania | Ukraine | Mexico | Finland |
China | Democratic Republic of Congo | Kenya | Bolivia | Netherlands |
Sudan | Iraq | Mozambique | Uruguay | Australia |
Indonesia | Bangladesh | Niger | New Zealand | |
Philippines | Yemen | Egypt | ||
Angola | Haiti | |||
Turkey | South Africa | |||
Brazil | ||||
Nigeria | ||||
Nepal |
Australia | Kenya |
Bangladesh | Mexico |
Bolivia | Nigeria |
China | Pakistan |
Egypt | Russia |
Ghana | Senegal |
India | South Africa |
Indonesia | United Kingdom |