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Listeria monocytogenes is a common foodborne pathogen affecting public health. Thus, detecting L. monocytogenes, even at low levels, in food matrices is essential. However, the current culture methods used for its detection and quantification are time consuming and difficult owing to background flora and interference by food matrices. DNA-based assays depend on DNA extraction and purification techniques. No optimal DNA extraction kit has been developed for analyzing L. monocytogenes in dairy products by real-time quantitative PCR (RT-qPCR). Therefore, in this study, we aimed to determine the efficiency of three DNA extraction kits for detecting L. monocytogenes in dairy products by RT-qPCR. We tested the efficiency of three commercial kits for DNA extraction from L. monocytogenes artificially inoculated in milk and dairy products. For the PrepSEQ rapid spin sample preparation kit and Exgene Cell SV mini, the limit of detection of was 100, 100, and 101 CFU/mL L. monocytogenes in milk, processed cheese, and infant formula, respectively, whereas that of the QIAamp DNA mini kit was 101, 103, and 102 CFU/mL, respectively. In addition, the Exgene Cell SV mini was better than the PrepSEQ rapid spin sample preparation kit for obtaining a standard curve for RT-qPCR of L. monocytogenes DNA in milk and dairy products, with a high correlation coefficient and amplification efficiency. The results of this study may be valuable for diagnostic laboratories and for developing an effective extraction method for processing food samples, such as dairy products, to subsequently detect and quantify L. monocytogenes by RT-qPCR.

This study was performed to develop and validate a predictive growth model of pathogenic Escherichia coli to ensure the safety of fresh‐cut produce. Samples were inoculated with a cocktail of seven E. coli strains of five pathotypes (EHEC, Enterohemorrhagic E. coli; ETEC, Enterotoxigenic E. coli; EPEC, Enteropathogenic E. coli; EIEC, Enteroinvasive E. coli, and EAEC, Enteroaggregative E. coli) and stored at 4, 10, 12, 15, 25, 30, and 37°C. Growth of pathogenic E. coli was observed above 12°C. The primary growth model for pathogenic E. coli in fresh‐cut produce was developed based on the Baranyi model. The secondary model was developed as a function of temperature for lag phase duration (LPD) and maximum specific growth rate (μmax) based on the polynomial second‐order model. The primary and secondary models for pathogenic E. coli were fitted with a high degree of goodness of fit (R2 ≥ 0.99). The bias factor (Bf), accuracy factor (Af), and root mean square error (RMSE) were 0.995, 1.011, and 0.084, respectively. The growth model we developed can provide useful data for assessing the quantitative microbial risk of pathogenic E. coli in fresh‐cut produce intended for human consumption. In addition, it is thought to be widely available in industries that produce, process, distribute, and sell fresh‐cut produce., Primary model of the growth of pathogenic Escherichia coli in fresh‐cut produce. (A) 4°C, (B) 10°C, (C) 12°C, (D) 15°C, (E) 25°C, (F) 30°C, (G) 37°C.

Purpose This study compared the quality of treatment plans for early‐stage, left‐sided breast cancer, as planned for and delivered by the HalcyonTM and VitalBeam®. Materials and methods Fifteen patients diagnosed with early‐stage left‐sided breast cancer, who had received VMAT with hypofractionated SIB, were recruited. All cases were planned using HalcyonTM comprising a dual‐layer MLC (DL‐MLC) and VitalBeam® with a Millennium 120 MLC (VB‐MLC). For the PTVs, the quality of coverage (QC), conformity index (CI), and homogeneity index (HI) were calculated for each plan. The dosimetric differences between the two treatment plans were statistically compared using the Wilcoxon signed‐rank test (p

In school choice problems, a list of restrictions have been imposed on priorities to achieve desirable properties of rules. However, it is difficult to verify these “acyclicity” conditions and identify the structure of the restricted priority profiles. To improve visibility and verifiability, we provide characterizations of these conditions. We also present the logical relations among the conditions by using our characterizations.

Shiga toxin-producing Escherichia coli (STEC) strains are important food-borne pathogens that can be transmitted through the consumption of food products derived from pigs. Moreover, antimicrobial ...

Recent developments in immunosuppressive protocols have enabled patients to receive kidney transplants from biologically incompatible donors. We propose to use immunosuppressants as a part of kidney exchange program. We introduce the “pairwise cycles and chains (PCC)” solution and show that it is Pareto efficient, monotonic, and maximizes the number of compatible transplants and the total number of transplants at the same time among all monotonic matchings.

This study aimed to monitor microbial contamination levels in a variety of health functional foods and to establish new microbial criteria. Indicator organisms (i.e., aerobic bacteria, coliform bacteria, and Escherichia coli) were monitored in 10 health functional food categories (743 items, 3,715 samples). The mean total aerobic counts of ginseng and Korean red ginseng were -0.35 and -0.74 log CFU/g; and the mean total coliform counts were -1.4 and -1.39 log CFU/g, respectively. In addition, the mean total coliform counts of fiber and protein products were -1.34 and -1.22 log CFU/g, respectively. However, no aerobic or coliform cells were detected in any other health functional food products (vitamins, minerals, probiotics, milk thistle extract, propolis, eicosapentaenoic acid, docosahexaenoic acid, or lutein products), and no E. coli was detected in any of the categories. These results can potentially be used to update the microbial criteria of the Health Functional Food Code.

Owing to convenience, ease of preparation, and price, the consumption of commercial kimchi is gradually rising in South Korea. Here, we estimated the risk level posed by pathogenic Escherichia coli in commercial kimchi products using the quantitative microbial risk assessment (QMRA) approach to develop measures for preventing potential foodborne outbreaks from kimchi consumption. We collected 610 samples of commercial kimchi products produced in Korea, 267 kimchi samples from foreign countries imported to Korea, and 187 raw materials used in kimchi preparation, and analyzed them for contamination with pathogenic E. coli. A Predictive model was developed to observe the survival characteristics of pathogenic E. coli. A dose-response model was selected, and the risk level was estimated using @RISK software. Although a prior epidemiological study indicated the frequent occurrence of foodborne outbreaks arising from contaminated kimchi products consumed in food service facilities, we found a low probability of foodborne illness caused by pathogenic E. coli in commercial kimchi products.

BackgroundThe method of solely using a black box model for radiation toxicity prediction in patients with lung cancer has limitations in explaining the causality of the prediction results. Therefore, the feature importance of predictors was analyzed using explainable artificial intelligence.Materials and MethodsPredictions were made for the clinical prognosis through SHAP analysis (Shapley additive explanations) by using pneumonia, interstitial lung disease, chronic obstructive pulmonary disease, concurrent chemoradiation therapy, age, and dosimetric factors [lung volume receiving ≥20 Gy (V20), mean lung dose (MLD)] as prognostic factors in 110 lung cancer patients who received radiation therapy. The model was analyzed using a random forest regressor and a tree explainer; and the SHAP analysis was used to examine the features of prognostic factors affecting radiation side effects and to derive mutual impact.ResultsFor patients with grade 2 toxicity, pneumonia, MLD, and V30 were analyzed as very important factors in the prediction results. However, for grade 0 toxicity patients, V30 and MLD were identified as the predictors that had a more important impact (SHAP value=0.7) than pneumonia. In addition, pneumonia had a decisive influence on the prognosis for future side effects of grades 1 and 2 or higher, and MLD was found to have a correlation with pneumonia and SHAP value=0.38. Moreover, through this prediction model, the predicted result for patients with mild radiation pneumonitis by the ground truth of a specific patient was 1.6 (close to grade2), and MLD>20 Gy, pathology, V20, and V30 were analyzed as high-risk factors in predicting radiation side effects. The accuracy, sensitivity and specificity of the model system were 0.88, 0.79, and 0.78, respectively.ConclusionThrough this study, MLD and V30 were analyzed as important predictors of side effects, and the features of each factor were analyzed for the degree of importance by the SHAP value. To predict radiation pneumonia using this method, a personalized analysis was conducted to identify the factors that influenced each patient. Through this process, comparisons were made with the existing black box method, which confirmed that increasing the explainability can reinforce an in-depth analysis of radiation side effect prediction.

A recent development of immunosuppressive protocols (or simply, suppressants) offers a new option to patients suffering from end-stage renal disease: transplants from biologically incompatible donors. Suppressants are currently being used for direct transplants within patient-donor pairs, but they can be utilized more efficiently when combined with kidney exchanges. To assess the welfare gains from doing so, we introduce the "minimum chains algorithms" for different sizes of feasible exchanges. Using these algorithms, we calculate the minimal number of suppressants needed for transplants for a group of patient-donor pairs. Our simulation results show that (i) a significant reduction of suppressants can be achieved by implementing this proposal, (ii) it suffices to arrange 2-way exchanges for the best use of suppressants, and (iii) the welfare gain varies with the ABO blood-type distribution, and the gain in Korea appears to be larger than that in the United States. Finally, we assess the value (or cost) of each patient-donor pair by comparing the outcomes of the pools with and without the pair.

Shiga toxin-producing

Twenty extended-spectrum β-lactamase (ESBL)-producing E. coli strains were isolated from imported meat in South Korea. ESBL strains of E. coli were detected in chicken (14/20) more often than in pork (6/20) and beef (0/20); the highest number (12/20) was detected in Brazilian meats. The blaCTX-M genes were predominant in meats from many countries. E. coli from pork imported from France produced the blaCTX-M-58 enzyme, which has never been documented previously in ESBL-producing bacteria from clinical or environmental sources. Additionally, the coexistence of the blaCTX-M-2 and blaOXA-1 enzymes in EC12-5 isolate was found for the first time in an ESBL E. coli isolate. A rare blaCTX-M type, blaCTX-M-25, was found in 40% of ESBL E. coli isolates. Phenotypic susceptibility testing showed that E. coli isolates were resistant to up to eleven antibiotics, including ciprofloxacin. For the first time, a new combination in an integron gene cassette, aacA4-cmlA6-qacEΔ1, was found in an E. coli isolate from poultry imported from Brazil. Three E. coli ST117 isolates, from an avian pathogenic lineage producing CTX-M-94, harbored fimH, fyuA, iutA, papC, rfc, and traT virulence genes and were not susceptible to quinolones. For the first time, rfc and papG virulence factors were detected in ESBL E. coli strains isolated from meat products. Even though E. coli CC21 and CC22 were obtained from meats from the USA and Brazil, respectively, they had a similarity coefficient higher than 99% in rep-PCR and the same MLST type (ST117), phenotypic antibiotic resistance pattern, integron gene (qacEΔ1), and plasmid DNA profile. This study indicates that imported meat products may be a source of ESBL-producing E. coli strains in South Korea.

We study the school choice problem in which a school district assigns school seats to students. There has been a long debate over the three best-known rules for this problem: the deferred acceptance rule (DA), the top-trading cycles rule (TTC), and the immediate acceptance rule (IA). We evaluate these rules by investigating how often they satisfy three central requirements, efficiency, fairness, and consistency. We compare the restricted domains of students’ preferences on which each rule satisfies these requirements. From the containment relations between them, we show that DA performs better than IA, which itself performs better than TTC in terms of efficiency and fairness. If we consider consistency instead, IA performs better than DA, which itself performs better than TTC.

The aims of this study was to determine the actual levels of microbial contamination in cereal and Saeng-sik products and establish new microbial criteria for cereal and Saeng-sik products for the “Korea Food Code”. Monitoring microbial indicator organisms (i.e., total aerobic, coliform, and Escherichia coli counts) and food-borne pathogens (i.e., Bacillus cereus, Staphylococcus aureus, and Clostridium perfringens) revealed that the total aerobic counts of cereal and Saeng-sik products were not detected (ND)–2.48 and 4.00–7.88 log10 CFU/g, respectively, whereas coliform bacteria were only detected in Saeng-sik (ND–5.24 log10 CFU/g). Cereals and Saeng-sik products were also contaminated with B. cereus (ND–2.95 log10 CFU/g and −0.40–3.30 log10 CFU/g, respectively). However, S. aureus, C. perfringens and E. coli were not detected in any of the cereal or Saeng-sik products. Based on this study, a revision was proposed for microbial criteria in cereal and Saeng-sik products.

PURPOSE/OBJECTIVE(S) Our aim is to determine maximum respiratory amplitude (RAmax) through the correlation between 4DCT analysis indices. We compare the plan quality between specific phase plans based on the determined the correlation, and consequently, we determine optimized phase in lung 4-Dimensional Stereotactic Body Radiotherapy (4D SBRT). MATERIALS/METHODS A total of 40 lung cancer patients (right sided: 20 patients, left sided: 20 patients) were enrolled in the study. Spearman correlation coefficient was used to study the relationship between 4DCT analysis indices (respiratory amplitude, volume). We regarded the relationship to establish specific phase plans (plan0-90%, plan20-70%, plan40-60%). Patients were prescribed 56 Gy for PTV and 60 Gy for ITV in 4 fractions complied with institutional protocol. VMAT (2-half arcs) plans were generated for each patient with 6 MV FFF beam of Linear accelerator. All plans were optimized that at least 95% of targets to be covered by the prescription dose. For targets, we compared plan quality between the specific phase plans using Quality of Coverage (QC), Conformity Index (CI), Homogeneity Index (HI) and Quality factor (QF). Dose constraints for OARs applied with RTOG 0915 protocol (ipsilateral, contralateral, whole lung: V5Gy 0.05). For OARs, there were significant differences with right sided (ipsilateral lung: D1500cc; 0.36i¾0.42 Gy, 0.25i¾0.27 Gy, 0.19i¾0.22 Gy, D1000cc; 1.36i¾1.58 Gy, 0.98i¾0.96 Gy, 0.77i¾0.79 Gy, P-value 0.05). CONCLUSION The study indicates that it is possible to determine the optimized phase through the correlation between 4DCT analysis indices, which can be applied it to treat in lung 4D SBRT. AUTHOR DISCLOSURE E. Heo: None. M. Kim: None. C. Park: None. K. Kim: None. J. Shim: None. H. Hwang: None. N. Lee: None. Y. Park: None. C. Kim: None. S. Lee: None.

The present study analyzed the prevalence and molecular characterization of Campylobacter at different processing steps in poultry slaughterhouses to determine where contamination mainly occurs. A total of 1,040 samples were collected at four different stages (preprocessing cloacal swabs, postevisceration, postwashing, and postchilling) in two processing plants. Campylobacter was detected in 5.8% (15 of 260) of the cloacal swabs and in 13.3% (104 of 780) of the processing samples. In both plants, the sampling points with the greatest contamination rates were after evisceration (20.5% and 15.4% for plants A and B, respectively) and significantly decreased after chilling (p 0.05, from 20.5% to 10.9%) in plant A and after washing (from 15.4% to 2.9%) in plants B. In the result, however, the reduction in Campylobacter contamination was achieved through the sequential processing procedures in both plants. Campylobacter loads (10

Equity and diversity issues are becoming more important in higher education and colleges are adopting various policies to address them. I am going to focus on college admissions and discuss two policies that are most commonly used in practice: affirmative action and need/merit-based financial aid. Here are what we have come up with so far and what can be done in the future.

In this study, changes in the prevalence of Salmonella during the processing of broiler chicken carcasses were investigated. A total of 1040 fecal swabs and chicken carcasses samples were collected from 2 processing plants at the 4 stages of broiler processing, which included live birds in slaughter line, postevisceration/prewashing, postwashing/prechilling, and postchilling, respectively. The intraspecific biodiversity of the Salmonella isolates was determined using a DiversiLab automated repetitive sequence-based PCR (rep-PCR) system. In both plants, the prevalence of Salmonella increased considerably after evisceration (from 4.6% to 30.8%, P 0.05). The most frequent Salmonella serovar in plant A was Infantis (35.8%), followed by Enteritidis (26.2%) and Montevideo (15.0%), while Montevideo (43.6%) and Enteritidis (35.9%) were most prevalent in plant B. A difference in the rep-PCR banding pattern was found to be related to the processing plant origin and serovar rather than sampling point or sampling day, although there were some exceptional strains.

We study solutions that choose lotteries for profiles of preferences defined over sure alternatives. We define Nash equilibria based on “stochastic dominance” comparisons and study the implementability of solutions in such equilibria. We show that a Maskin-style invariance condition is necessary and sufficient for implementability. Our results apply to an abstract Arrovian environment as well as a broad class of economic environments.

During a nationwide surveillance in Korea, 13 methicillin-resistant Staphylococcus aureus (MRSA) strains were isolated from imported and domestic meat between 2009 and 2011. The predominant MRSA genotype was SCCmec type V, and only two agr types (I and II) were found. Unexpectedly, sequence type ST72 comprised more than 50% of the isolates; this is the first instance of type ST72 in food from Canada. Two Spanish pork isolates were ST398, which caused human disease in Europe, and they carried leukotoxin genes, lukS, lukF, and lukE-lukD. Furthermore, P71 and P6 harbored all of the known leukocidin genes, lukS-lukF-lukE-lukD-lukM. Our collected MRSA strains were multidrug resistant with various antimicrobial and heavy-metal resistance genes. Toxin genes that are commonly found in clinical MRSA also were detected in our meat strains. One MRSA strain exhibited an uncommon type of enterotoxin, sec-see-seg-sei-sel-sem-sen-seo-sep. Plasmids (1.5-15.0 kb) were found in 12 of the 13 MRSA isolates. Repetitive sequence-based polymerase chain reaction of the genomic DNA showed 3 clusters with 95% similarity. The presence of multidrug-resistant and toxigenic MRSA in meat products suggests that comprehensive surveillance should be continued for imported meats in Korea.

We conducted a survey of Salmonella from 8 egg-breaking plants and a farm to determine the prevalence and the source of the bacteria. The contents of 2400 shell eggs (20 eggs per pool), 75 pasteurized liquid egg products, and 120 unpasteurized liquid egg products from 8 egg-breaking plants in South Korea were examined. In liquid egg samples, 4 Salmonella-positive samples from 120 unpasteurized ones (3.3%) and 5 positive samples from 75 pasteurized ones (6.7%) were identified; no eggs were positive for Salmonella among shell egg samples. To trace the source of Salmonella, we revisited the 2 Salmonella-positive plants (plants A and C). We investigated the equipment and environments of the plants and a henhouse (farm A) that supplied shell eggs to plant A, and collected additional liquid eggs and shell eggs from plants A and C. All Salmonella isolates from plant A and the associated farm A, except for a single Typhimurium strain from farm A, were serotyped as Bareilly. Three serovars, including one Bareilly, four Tennessee, and one Richmond, were isolated from plant C. Most Salmonella isolates were susceptible to tested antibiotics. To identify differences between isolates, molecular subtyping by using the automated rep-PCR system was conducted. All Salmonella Bareilly (S. Bareilly) strains from plant A exhibited high similarity, indicating possible contamination by Salmonella strains from the henhouse A. Meanwhile, 2 S. Bareilly strains from plant C, one from liquid egg at the 1st visit and the other from container at the 2nd visit, exhibited identical antibiotic resistance and similar subtyping pattern, but clearly discriminated from the ones of plant A.

The identity of 45 Hanwo and 47 imported beef (non-Hanwoo) samples from USA and Australia were verified using the microsatellite (MS) marker and single nucleotide polymorphism (SNP) methods. Samples were collected from 19 supermarkets located in the city of Seoul and Gyeonggi province, South Korea, from 2009 to 2011. As a result, we obtained a 100% concordance rate between the MS and SNP methods for identifying Hanwoo and non-Hanwoo beef. The MS method presented a 95% higher individual discriminating value for Hanwoo (97.8%) than for non-Hanwoo (61.7%) beef. For further comparison of the MS and SNP methods, blood samples were collected and tested from 54 Hanwoo × Holstein crossbred cattle (first, second, and third generations). By using the SNP and MS methods, we correctly identified all of the first-generation crossbred cattle as non-Hanwoo; in addition, among the second and third generation crossbreds, the ratio identified as Hanwoo was 20% and 10%, respectively. The MS method used in our study provides more information, but requires sophisticated techniques during each experimental process. By contrast, the SNP method is simple and has a lower error rate. Our results suggest that the MS and SNP methods are useful for discriminating Hanwoo from non-Hanwoo breeds.

In this study, the bacteriological survey was examined on ice creams at manufacturing factories in Korea during the summer season of 2011. The nineteen selected among 166 samples by preliminary test were col- lected from 11 different manufacturing factories in four major manufacturers in May 2011. Samples from ice milk, ice creams, sherbets, and non milk fat ice creams were tested for the total aerobic bacteria, coliform bacteria, and five food borne pathogens, respectively. The results showed that the coliforms including E. coli O157:H7, Salmonella spp., Sta- phylococcus aureus, Clostridium perfringens, and Listeria monocytogenes were not detected on all the ice creams. The total aerobic bacteria of the packed samples examined ranged between 2.5 × 10 3 and 5.5 × 10 5 cfu/g. One ice cream, two sherbets, and four ice milk samples exceeded the acceptable limits of total aerobic bacteria according to the Korean standards for ice cream (1.0 × 10 5 cfu/g) and others (5.0 × 10 4 cfu/g). The levels of these microorganisms from ice creams were higher in three original equipment manufacturers than seven self-manufacturers. Three of ten ice creams (30.0%), three of six ice milks (50.0%), and one of two sherbets (50%) exceeded the acceptable limits of total aerobic bacteria, respectively. The personnel hygiene procedures with chocolate and vanilla chip addition from the manufacturing process were the main sources of the microbial contamination of stick-bar type ice creams when being produced in a factory. Improvement of the hazard analysis critical control points (HACCP) system should be introduced into the ice cream factory to improve the microbial quality of the ice cream products in Korea.

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit ® on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit ® on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kit TM resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit ® on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit ® : 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-con- tamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demon- strated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamina- tion during manufacturing process.

This study developed predictive models for the kinetic behavior of Staphylococcus aureus on pro- cessed cheeses. Mozzarella slice cheese and cheddar slice cheese were inoculated with 0.1 ml of a S. aureus strain mixture (ATCC13565, ATCC14458, ATCC23235, ATCC27664, and NCCP10826). The inoculated samples were then stored at 4 o C (1440 h), 15 o C (288 h), 25 o C (72 h), and 30 o C (48 h), and the growth of all bacteria and of S. aureus were enumerated on tryptic soy agar and mannitol salt agar, respectively. The Baranyi model was fitted to the growth data of S. aureus to calculate growth rate (µmax; log CFU·g �1 ·h �1 ), lag phase duration (LPD; h), lower asymptote (log CFU/ g), and upper asymptote (log CFU/g). The growth parameters were further analyzed using the square root model as a function of temperature. The model performance was validated with observed data, and the root mean square error (RMSE) was calculated. At 4 o C, S. aureus cell growth was not observed on either processed cheese, but S. aureus growth on the mozzarella and cheddar cheeses was observed at 15 o C, 25 o C, and 30 o C. The µmax values increased, but LPD values decreased as storage temperature increased. In addition, the developed models showed acceptable perfor- mance (RMSE = 0.3500-0.5344). This result indicates that the developed kinetic model should be useful in describing the growth pattern of S. aureus in processed cheeses.

We study the problem of assigning objects to a set of agents. We focus on probabilistic solutions that only take agents’ preferences over objects as input. Importantly, agents may be indifferent among several objects. The “extended serial correspondence” is proposed by Katta and Sethuraman (J Econ Theory 131:231–250, 2006) to solve this problem. As a follow-up to Liu and Pycia (Ordinal efficiency, fairness, and incentives in large markets. Mimeo, 2012) who introduce the notion of profiles with “full support”, we work with two interesting classes of preference profiles: profiles that (i) have rich support on a partition or (ii) are single-peaked with rich support on a partition. For each profile in these classes, an assignment matrix is selected by the extended serial correspondence if and only if it is sd-efficient and sd envy-free. We also provide an asymptotic result.

Salmonella Enteritidis is responsible for causing foodborne diseases upon consumption of egg products. While cases of S. Enteritidis isolation from eggs have been reported in other countries, no such cases have previously been reported in Korea. In this study, we report the first isolation and identification of S. Enteritidis from domestically distributed eggs in Korea. Eggs were collected from eight countrywide grocery stores during different seasons between 2011 and 2012. Egg contents and washing solution of egg shells were incubated in buffered peptone water, and the enriched broth was further enriched in tetrathionate broth and Rappaport-Vassiliadis. The secondary enriched broth was streaked on xylose lysine desoxycholate agar. The suspected colonies were confirmed to S. Enteritidis by a biochemical test, serotyping, and PCR test. Genetic relatedness among the isolates was analyzed using Diversilab Salmonella kit. Three strains of S. Enteritidis were isolated from egg contents and egg shells collected from grocery stores of the Eumseong-city in the fall of 2011. All three stains showed resistance to chloramphenicol, streptomycin, nalidixic acid, and ampicillin by the disk diffusion method. In addition, the isolates showed more than 99% DNA homology, indicating that they were presumably identical strains. Therefore, there is a requirement to monitor and control against S. Enteritidis from eggs in Korea.

Salmonella I 4,[5],12:i:- was a monophasic variant of Salmonella (S.) Typhimurium and notorious for re-emerging candidate which would replace S. Typhimurium DT104 for antibiotic resistance. Recently, isolation rate was increased on human and industrial animals but there was no case in domestic animals but human in Korea. This was first isolation case from domestic animals in Korea. The five isolates from feces of duck (n = 3), chicken (n = 1), and wild bird (n = 1) showed antibiotic resistance against cephems and aminoglycosides. These means that the spread of emerging bacterial pathogens to domestic animals and the need of systemic management for Salmonella I 4,[5],12:i:-.

We consider the problem of selecting the locations of two (identical) public goods on an interval. Each agent has preferences over pairs of locations, which are induced from single-peaked rankings over single locations: each agent compares pairs of locations by comparing the location he ranks higher in each pair. We introduce a class of “double median rules” and characterize it by means of continuity, anonymity, strategy-proofness, and users only. To each pair of parameter sets, each set in the pair consisting of $$(n+1)$$ parameters, is associated a rule in the class. It is the rule that selects, for each preference profile, the medians of the peaks and the parameters belonging to each set in the pair. We identify the subclasses of the double median rules satisfying group strategy-proofness, weak efficiency, and double unanimity (or efficiency), respectively. We also discuss the classes of “multiple median rules” and “non-anonymous double median rules”.

In vitro activities of 13 antibiotics were assessed against 85 Brucella abortus isolates from naturally infected cattle in the Republic of Korea during 1998-2006, using broth microdilution test. Tetracyclines showed the most excellent activity against B. abortus, displaying MIC values of 0.5 μg/ml or below. In particular, minocycline showed the lowest MIC 50/90 values (0.125/0.125 μg/ml) in this study. Among four fluoroquinolones tested, ciprofloxacin (MIC 50/90 , 0.5/1 μg/ml) and norfloxacin (MIC 50/90 , 8/8 μg/ml) had the most and the least activities, respectively. Gentamicin (MIC 50/90 , 1/1 μg/ml) was more effective than streptomycin, erythromycin, rifampin, and chloramphenicol (MIC 50/90 , 2/2 μg/ml).

We compared between an automated most-probable-number technique TEMPO ® TVC and tradi- tional plating methods Petrifilm TM for estimating populations of total aerobic bacteria in various livestock products. 257 samples randomly selected in local retail stores and 87 samples inoculated with E. coli ATCC 25922, Staphylo- coccus aureus ATCC 12868 were tested in this study. The degree of agreement was estimated according to the CCFRA (Campden and Chorleywood Food Research Association Group) Guideline 29 and the agreement indicates the differ- ence of two kinds methods is lower than 1 log base 10(log10 ). The samples of hams, jerky products, ground meat prod- ucts, milks, ice creams, infant formulas, and egg heat formed products were showed above 95% in the agreement of methods. In contrast, proportion of agreement on meat extract products, cheeses and sausages were 93.1%, 92.1%, 89.1%, respectively. One press ham and five sausages containing spice and seasoning, two pork cutlets containing spice and bread crumbs, two meat extract product and two natural cheeses and one processing cheese with a high fat content, and one ice cream containing chocolate of all samples showed the discrepancy. Our result suggest that TEMPO ® TVC system is efficient to analyses total aerobic bacteria to compare manual method in time-consuming and

A blocking enzyme-linked immunosorbent assay (ELISA) with a baculovirus-expressed structural protein was developed for the detection of antibodies to foot-and-mouth disease virus type A. It exhibited 99% specificity with a cutoff of 53% inhibition. Its sensitivity was comparable to the sensitivities of the virus neutralization test and the liquid-phase blocking ELISA, indicating its potential as an alternative assay.