Real-time PCR detection of the thermostable direct hemolysin and thermolabile hemolysin genes in a Vibrio parahaemolyticus cultured from mussels and mussel homogenate associated with a foodborne outbreak

Molecular methods have become vital epidemiological tools in the detection and characterization of bacteria associated with a foodborne outbreak. We used both culture and real-time PCR to detect a Vibrio parahaemolyticus isolate associated with a foodborne outbreak. The outbreak occurred in July 2002 in Polk County, Florida, and originated at a Chinese buffet, with one person being hospitalized. The hospital isolated V. parahaemolyticus from the patient but destroyed the sample after diagnosis. From an onsite visit of the restaurant, food samples that possibly contributed to the outbreak were collected and sent to the Florida Department of Health, Tampa Branch Laboratory. Crab legs, crabsticks, and mussel samples were homogenized and incubated according to the Food and Drug Administration Bacteriological Analytical Manual culture protocol. Three sets of primers and a TaqMan probe were designed to target the tdh, trh, and tlh genes and used for real-time PCR. This study was successful in isolating V. parahaemolyticus from a mussel sample and detecting two of its genes (tdh and tlh) in food and pure culture by real-time PCR.     

Estimating horizontal drain design by the finite-element and finite-difference methods

The presence of water is one of the most critical factors contributing to the instability of tailings embankments. Nonexistent or inefficient drainage facilities usually result in a high phreatic surface that can cause the embankment to fail. One possible solution, especially for remedial situations, is the installation of horizontal drains. An investigation into the effects of horizontal drains on the phreatic surface of tailings embankments was conducted by the Bureau of Mines. A laboratory model was constructed to correlate the effects of various drain spacing and length combinations with results from computer codes. A three-dimensional finite-element computer code and a two-dimensional finite-difference computer code were used. Two existing tailings embankments were modeled and potentiometric data were compared to the computer results. The two-dimensional finite-difference code and the three-dimensional finite-element code produced nearly the same location for the phreatic surface between drains. The location of the phreatic surface from the codes was slightly above the phreatic surface of one field application and followed the trend of the other closely. The phreatic surface location of the laboratory model was slightly above that of the computer-generated phreatic surface. The distance between the phreatic surfaces of these models became larger as drain length increased or drain spacing decreased. Dimensionless graphs were constructed for estimating phreatic surface location for embankments with horizontal drains.     

Comparison of antibiotic susceptibility profiles and molecular typing patterns of clinical and environmental Salmonella enterica serotype Newport

The genus Salmonella is composed of more than 2,400 serotypes, many of which cause enteric diseases in humans and animals. Several Salmonella serotypes are multidrug resistant, and there is evidence of the clonal spread of these strains from animals to humans. Salmonella enterica serotype Newport is one of the serotypes that increasingly present a multidrug-resistant phenotype. Source tracking and antibiotic resistance testing are important considerations for identifying the outbreak strain. The first goal of this study was to examine the antibiotic susceptibility patterns of clinical and environmental Salmonella Newport isolates from various geographic locations and to compare the discriminatory ability of two DNA fingerprinting techniques. The second goal was to determine whether the antibiotic resistance profiles and typing patterns correlated. Thirty Salmonella Newport isolates, including environmental and human clinical strains, were subjected to pulsed-field gel electrophoresis (PFGE), ribotyping, and antibiotic susceptibility testing. Eighty percent of the isolates showed total or intermediate resistance to one or more drugs; 75% of the isolates were multidrug resistant. Ribotyping with the EcoRI enzyme and PFGE with the XbaI enzyme each divided the isolates into 14 groups. Cluster analysis based on antibiotic susceptibility patterns generated 23 profiles. The susceptible and resistant isolates were not differentiated on the basis of either of the molecular typing techniques. Hence, no correlation was observed between the antibiotic resistance profiles and the DNA subtyping patterns. In conclusion, ribotyping is as discriminatory as PFGE and, when used in combination with antibiotic resistance profiles, provides a powerful tool for the source tracking of Salmonella Newport.     

Financial Appraisal of a Small Scale Wind Turbine with a Case Study in Ireland

This research seeks to evaluate the economic benefits to be gained by installing a small-scale wind turbine for a customer with a three-phase electrical supply requirement. The evidence for the claims made in this paper is obtained by using actual data obtained from the installed equipment over a three year period. The objective is to accurately appraise the financial investment using real data. There appears to be limited studies conducted into this type of research, possibly because the renewable energy sector is in the infancy stage in the host country, Ireland. There are some wind energy installations with financial appraisal techniques based on modeled data, which may, or may not, be accurate. The study concludes by claiming that the financial benefits of the wind energy turbine installation had disappointing results when compared to predicted benefits based on modeled data.     

Virtual realia: maneuverable computer 3D models and their use in learning assembly skills

Two experiments compared real and virtual models as aids for learning assembly skills. In Experiment 1, ten participants individually studied either a fully assembled model, or a computer-generated one, in exploded view, that could be spatially manipulated in any direction. Participants then assembled the object in front of a video camera. ANOVA indicated virtual model are studied significantly longer but yield faster assembly than a real model. Experiment 2 used the same treatments plus a fully assembled virtual mode, randomly assigned to 28 participants who studied the aid, assembled the model, and then repeated the task from memory 3 days later. ANOVA indicated no differences between the three groups in assembly speed or accuracy. However, participants studied the exploded virtual model significantly longer than the two intact views of the model suggesting the former may impose a greater cognitive load due to the additional visual information it provides.     

Determination of plastic viscosity for brown coal pastes using an instrumented mixer

Flow curves are generated for lignite pastes using an instrumented measuring kneader, converting the torque and rpm to shear stress and shear rate data, respectively. Contrary to previous findings obtained when instrumentation of this kind was unavailable for these applications, the pastes are yield pseudoplastic in nature, with significant differences between actual and Bingham yield stresses. Flow curves were generated over for 14, 17 and 22 °C for as-mined lignite paste, 54% moisture, wet basis (w.b.), and increased moisture concentrations, through moisture addition, of 56 and 58%, w.b. Flow curves for the latter were generated at 14 and 22 °C. The flow properties presented are the plastic viscosities and, using Hershel Bulkley and Bingham fits, yield stresses. In general, the pastes exhibited high yield stresses (2-5.3 kPa, depending on the moisture content and process temperature), high Bingham yield stresses (2-8 kPa), and low plastic viscosities (0.5-29.4 Pa s). Increasing temperature and/or moisture content resulted in reductions in the magnitudes of these properties.     

Characteristics associated with real and made-up events: The effects of event valence, event elaboration, and individual differences.

In three studies, participants rated both real and made-up personal events on several different characteristics. These included meta-cognitive beliefs about the perceived realness and typicality of these events, imagery ratings of visual detail, and emotional ratings of intensity and feelings. Studies 1 and 2 explored the impact of event valence (pleasant versus unpleasant) on these characteristics, whereas Study 3 focused on the effects of event elaboration involving guided imagery and journaling techniques. All three studies also included consideration of individual difference factors that might either enhance or attenuate the ratings that were obtained. Both Studies 1 and 2 found that pleasant events (be they real or made-up), were viewed as more typical, and more likely to have happened and be true, than unpleasant events. This pattern of meta-cognitive judgments provided support for a general positivity hypothesis, which proposes that most individuals orient towards and emphasize pleasant rather than unpleasant life experience and events. In contrast, the imagery-related components of these events, such as visual details, location, and time, were much less sensitive to the manipulation of event valence. Strong imagery-related effects, however, were noted when events were elaborated in the final study. Furthermore, this event elaboration manipulation also resulted in heightened meta-cognitive judgments of typicality, likelihood of the event having happened, and of being true. Finally, across all three studies, a series of correlational analyses indicated that the individual difference factors did not have any systematic effect on any of the event characteristic ratings. However, when event valence was not specifically manipulated (in Study 3), depressed individuals spontaneously provided twice as many unpleasant personal events as nondepressed individuals. These findings were then discussed in terms of source-confusion issues regarding personal memory accuracy, as well as the further extension of a recent model of autobiographical memory to incorporate event properties such as valence and elaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Concreteness and imagery effects in the written composition of definitions.

In 2 experiments, undergraduates composed written definitions of concrete and abstract nouns that were matched for frequency of usage and meaningfulness. Across both experiments, definitions of concrete words exhibited higher ratings for quality, greater length in words, shorter latencies, and more self-reports of an imagery strategy. Definitions for abstract words produced more self-reports of a verbal-associative strategy. The results replicate those of an earlier study involving oral production of definitions, suggesting that common cognitive mechanisms underlie the production of spoken and written language as explained by dual coding theory. Instructionally, the use of concreteness and imagination in composing definitions may lead to improved student writing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A low-cost wireless sensors positioning solution for indoor parking facilities management

A relatively low-cost system for indoor parking facilities management is proposed, which is a combined solution of RFID/WiFi and a MEMS IMU monitoring scheme. An RFID localisation module is proposed in the form of so-called virtual gates. To define such virtual gates, either RFID tags or readers are placed at known locations throughout the area of interest. In this study, a number of tags are fixed at known positions and a moving reader is carried by each participating vehicle. Based on this configuration set-up, the Cell of Origin (CoO) technique is applied, in which the system indicates the presence of the user carrying the reader in a cell around the tag location. To define a virtual gate, tags are installed along the parking lot corridors and at critical transit passages in the parking facility. The CoO technique is also proposed in the case of WiFi for location determination of vehicles in a multi-storey car park. In this study, WiFi is employed to monitor the passing vehicles and bridge the gap until a tag can detect a user’s reader again. Thus, a combined positioning solution of RFID and WiFi is achieved. As a complement to the proposed RFID/WiFi system, this study examines the potential and limitations of MEMS IMU sensors (i.e. accelerometers, gyroscopes and barometers) commonly found in modern smartphones. The paper concludes with a detailed discussion on the implications of alternative positioning techniques for indoor parking management.