Differential expression of two functional serine/threonine protein kinases from soybean that have an unusual acidic domain at the carboxy terminus

Two soybean cDNA clones, SPK-3 and SPK-4, encoding putative protein kinases were isolated and characterized. Both cDNAs encoded approximately 40-kDa serine/threonine kinases with unusual stretches of acidic amino acids in their carboxy-terminal regions, which are highly homologous to PKABA1 from wheat and ASKs from Arabidopsis. These kinases are encoded by one- or two-copy genes in the soybean genome. Notably, SPK-3 and -4 showed different patterns of expression in various soybean tissues. SPK-3 is highly expressed in dividing and elongating tissues of young seedlings but relatively weakly in tissues of mature plants. In contrast, SPK-4 showed relatively high and constitutive expression in all the tissues examined except for leaf tissues of mature plants. Although various stressors, such as dehydration and high salinity, increased the expression of both genes, the induction kinetics were different. The two genes also differed in their response to abscisic acid (ABA). SPK-3 was induced but SPK-4 was not affected by exogenously supplied abscisic acid. In accordance with these expression data analysis of the activity of a chimeric SPK-3 promoter::beta-glucuronidase (GUS) reporter gene by transient expression in tobacco leaves confirmed the inducibility of SPK-3 by salt and ABA. Polyclonal antibodies raised against a recombinant SPK-4 protein produced in Escherichia coli specifically recognized both recombinant SPK-3 and -4 proteins. Kinase assays using affinity-purified SPK-4/ antibody complexes with crude soybean extracts as substrate identified specific phosphorylation of two 41 and 170 kDa soybean proteins that were phosphorylated on serine residues. Taken together, our results suggest that SPK-3, and/or SPK-4 are functional serine protein kinase(s). Furthermore, SPK-3 and -4 may play different roles in the transduction of various environmental stresses.     

Determination of quantitative food consumption levels for use in microbial risk assessments: cheddar cheese as an example

Microbial risk assessment (MRA) is becoming increasingly used in the management of food safety because it can be used to quantify risks and help rank intervention strategies. The exposure assessment components of the assessments have become complex with many aspects of the contamination, survival, and growth of a pathogen in a food being taken into consideration. Insufficient consumption data constitutes an important data gap and consequently one of many sources of uncertainty in MRA even though the effects of uncertainty are smaller than those affecting bacterial concentration in foods. Therefore, food consumption data also play an important role in exposure assessment of MRA. In the United States, there are large-scale, nationwide sets of consumption data available for use in MRA, i.e., the National Health and Nutrition Examination Survey (NHANES). Newly released dietary interview data in the NHANES 2001 to 2002 survey show that it has been redesigned and that the data were sufficiently updated from previous versions to have more value for MRAs. We propose a model that can effectively use the new data sets and be incorporated into MRAs, using as an example consumption of Cheddar cheese/American-type cheese. This model included the prevalence of food eaten as well as the amount and frequency. We determined the amount of Cheddar/American cheese consumed per day with probability distribution (e.g., lognormal distribution). These could be further determined by gender, age, pregnancy, and combination food type, which we plan to do in the future. The frequency of the range of serving numbers for Cheddar/American cheese consumed per person per day and prevalence as the proportion of a population (e.g., survey respondents) eating a certain food in a day are also presented. Unlike traditional published mean values, the results of this model provide probability distribution intakes that can be compared with mean and median intakes. This allows values in the upper percentiles to be considered for inclusion in MRAs. We believe this simulation model can be adapted with different variables applicable to different foods, pathogens, and specific health risk population groups.     

Comparison of four molecular typing methods for the differentiation of Salmonella spp

A total of 57 strains of Salmonella spp. were differentiated by random amplification of polymorphic DNA (RAPD) fingerprinting using three different primers (OPL-03, primer 1, and primer A); by Enterobacterial Repetitive Intergenic Consensus (ERIC) fingerprinting; by ribotyping-PCR; and by Single Strand Conformation Polymorphism (SSCP). From the 57 strains, RAPD fingerprinting with primers OPL-03, 1, and A produced 42, 51, and 54 fingerprint patterns respectively. ERIC fingerprinting produced 50 patterns; ribotyping-PCR produced four patterns, and SSCP produced 11 patterns. Combinations of two different typing methods generally increased the discrimination of Salmonella strains. A combination of two different RAPDs or a combination of RAPD and ERIC was better than the other combinations. Discrimination using a combination of RAPD (primer 1 or primer A) and ERIC, which could differentiate all 57 Salmonella strains, was better than the combination of two RAPDs. This study indicated that the use of a combination of RAPD (primer 1 or primer A) and ERIC should be useful for the differentiation of field-isolated Salmonella strains and epidemiological studies.     

Wireless-adaptive fair scheduling for multimedia stream

As packet cellular networks are expected to support multimedia services, the authors incorporate the multimedia QoS requirements into the design of a new scheduling algorithm. The proposed wireless-adaptive fair scheduling tries to allocate time slots for each user with fair share by considering the varying channel condition while reflecting the stream requirements and achieving high throughput.     

FDF: Frequency detection-based filtering of scanning worms

In this paper, we propose a simple algorithm for detecting scanning worms with high detection rate and low false positive rate. The novelty of our algorithm is inspecting the frequency characteristic of scanning worms instead of counting the number of suspicious connections or packets from a monitored network. Its low complexity allows it to be used on any network-based intrusion detection system as a real-time detection module for high-speed networks.Our algorithm need not be adjusted to network status because its parameters depend on application types, which are generally and widely used in any networks such as web and P2P services. By using real traces, we evaluate the performance of our algorithm and compare it with that of SNORT. The results confirm that our algorithm outperforms SNORT with respect to detection rate and false positive rate.     

Origin of inhomogeneity in spark plasma sintered bismuth antimony telluride thermoelectric nanocomposites

Anisotropy and inhomogeneity are ubiquitous in spark plasma sintered thermoelectric devices. However, the origin of inhomogeneity in thermoelectric nanocomposites has rarely been investigated so far. Herein, we systematically study the impact of inhomogeneity in spark plasma sintered bismuth antimony telluride (BiSbTe) thermoelectric nanocomposites fabricated from solution-synthesized nanoplates. The figure of merit can reach 1.18, which, however, can be overestimated to 1.88 without considering the inhomogeneity. Our study reveals that the inhomogeneity in thermoelectric properties is attributed to the non-uniformity of porosity, textures and elemental distribution from electron backscatter diffraction and energy-dispersive spectroscopy characterizations. This finding suggests that the optimization of bulk material homogeneity should also be actively pursued in any future thermoelectric material research.

     

Whole-body and pinhole bone scintigraphic manifestations of Reiter''s syndrome: distribution patterns and early and characteristic signs

The characteristic whole-body and pinhole scintigraphic manifestations of osteo-enthesopathy and arthropathy in Reiter's syndrome (RS) are described, with an emphasis on early diagnosis. We analysed 59 sets of whole-body and pinhole bone scintigrams of 59 patients with RS. The population comprised 47 men and 12 women with an age range from 15 to 53 years (mean=29.4). Bone scintigraphy was carried out 2-2.5 h after intravenous injection of technetium-99m hydroxydiphosphonate using a single-head gamma camera (Siemens Orbiter Model 6601) with a low-energy high-resolution and a 4-mm pinhole collimator for whole-body and pinhole scintigraphy, respectively. In total 262 lesions of osteo-enthesopathy and arthritis were detected on 59 whole-body scintigrams, an incidence of 4.4 lesions per patient. As anticipated, the lesional distribution was asymmetrical: 68% were in the lower limb skeleton and 32% in the axial and upper limb skeleton. Pinhole bone scintigraphy, applied selectively to one region of interest in each case, enabled us to accurately diagnose arthritis and osteo-enthesopathy. It was noteworthy that osteo-enthesopathy, alone or in combination with arthritis, occurred in 78.9%, and had a strong predilection for the foot bones, especially the calcaneus (25. 6%). Pinhole scintigraphy detected enthesopathy in the absence of radiographic alteration in 14.1% of cases and portrayed characteristic signs of RS in 6.9%. Whole-body bone scintigraphy augmented with pinhole scintigraphy was found to be useful in order to panoramically display the systemic involvement pattern, to assess the characteristic bone and articular alterations and to detect early signs of RS.     

Development of Predictive Models for the Growth of Escherichia coli O157:H7 on Cabbage in Korea

Abstract: Cabbage is the main material of coleslaw, a popular side dish in Korea as well as many other countries. In the present study, the combined effect of temperature (15, 25, and 35 °C) and relative humidity (60%, 70%, and 80%) on the growth of Escherichia coli O157:H7 on cabbage was investigated. The polynomial models for growth rate (GR), lag time (LT), and maximum population density (MPD) estimated from the Baranyi model were conducted with high coefficients of determination (R²> 0.98). Subsequently, performance and reliability of the models were assessed through external validation, employing three indices as bias factor (B_f), accuracy factor (A_f), and the standard error of prediction expressed in percentage (%SEP). The B_f, A_f, and %SEP values of the predictive models for GR were 1.008, 1.127 and 18.70%, while 1.033, 1.187 and 20.79% for LT and 0.960, 1.044 and 5.22% for MPD, respectively. The results demonstrated that the developed secondary models showed a good agreement between the observed and predicted values. Therefore, the established models can be suitable to estimate and control E. coli O157:H7 growth risk on cabbage at some steps from farm to table in Korea as a valuable tool. Practical Application: The combined effect of temperature and relative humidity on the growth or survival of Escherichia coli O157:H7 on cabbage was investigated. The validated predictive models are qualified to provide good predictions for E. coli O157:H7 growth, which can help to conduct the quantitative microbiological risk assessment (QMRA) of E. coli O157:H7 on cabbage from farm to table in Korea.