Transfer of Salmonella and Campylobacter from stainless steel to romaine lettuce

The degree of transfer of Campylobacter jejuni and Salmonella enterica serovar Typhimurium was evaluated from a stainless steel contact surface to a ready-to-eat food (lettuce). Stainless steel coupons (25 cm2) were inoculated with a 20-microl drop of either C. jejuni or Salmonella Typhimurium to provide an inoculum level of approximately 10(6) CFU/28 mm2. Wet and dry lettuce (Lactuca sativa var. longifolia) pieces (9 cm2) were placed onto the inoculated stainless steel surface for 10 s after the designated inoculum drying time (0 to 80 min for C. jejuni; 0 to 120 min for Salmonella Typhimurium), which was followed by the recovery and enumeration of transferred pathogens (lettuce) and residual surface pathogens (stainless steel coupons). For transfers of Salmonella Typhimurium to dry lettuce, there was an increase from 36 to 66% in the percent transfer of the initial inoculum load during the first 60 min of sampling and then a precipitous drop from 66 to 6% in percent transfer. The transfer of Salmonella Typhimurium to wet lettuce ranged from 23 to 31%, with no statistically significant difference between recoveries over the entire 120-min sampling period. For C. jejuni, the mean percent transfer ranged from 16 to 38% for dry lettuce and from 15 to 27% for wet lettuce during the 80-min sampling period. The results of this study indicate that relatively high numbers of bacteria may be transferred to a food even 1 to 2 h after surface contamination. These findings can be used to support future projects aimed at estimating the degree of risk associated with poor handling practices of ready-to-eat foods.     

Evaluation of time-temperature integrators for tracking poultry product quality throughout the chill chain

The goal of this study was to evaluate the application of one type of time-temperature integrator (TTI) to monitor the microbiological quality of ice-packed raw chicken drumsticks as a function of temperature exposure. A kinetics-based model was used to correlate the TTI chroma response to the number of bacteria on the drumstick surface under constant- and variable-temperature conditions. Two constant-temperature studies (4 and 15 degrees C) and one variable-temperature study (4 degrees C for 24 h, 15 degrees C for 24 h, 4 degrees C constant) were conducted to evaluate the applicability of the TTI under ideal and worst-case situations. During the constant-temperature studies, quality predictions made at the midpoint of the product shelf life were accurate within 15% for the observed bacterial populations. The accuracy of the TTI was marginal in the initial and final stages of the response period. During the variable-temperature study, the TTI response demonstrated positive history effects, whereby the observed rate constant is affected by previous temperature exposure. After the TTIs had been held at 15 degrees C for 24 h, the TTI response rate constant observed during subsequent storage at 4 degrees C was higher than what would be predicted for 4 degrees C. Further work will be needed to develop a continuous TTI-based quality monitoring system. However, because the microbiological quality of fresh poultry could be reliably predicted with kinetic models, fresh poultry products would be excellent candidates for a TTI-based quality monitoring system.     

Europeanist-programme roadmap for optical communications generated by theoptimist thematic network

On the basis of Europeanist project results in the field of photonics, theoptimist thematic network has produced a roadmap for optical communications. This work is described in the present article which provides scenarios for the evolution of the optical network in the coming 10 years. Predictable developments in optical components, sub-systems and systems and their consequences on the architecture and performances of the networks are analysed. Specific interest is focused on the various parts of the network structure namely the access, the metropolitan area, the wide area and the global networks. Technical documents elaborated by theoptimist consortium and minutes fromist workshops can be found on the website http://www.ist-optimist.org/.[1]. They constitute a main source for further information.     

Improved Maxwell Model Approach and its Applicability toward Lifetime Prediction of Biobased Viscoelastic Fibers

The evaluation of relaxation measurements is a well-established technique for predicting the lifetime of polymer materials, with research primarily focusing on increasing prediction accuracy and minimizing material testing time. The current study presents a novel approach toward describing the long-term behavior of viscoelastic polymers based on the Maxwell model. It assumes a mean relaxation time of the polymer chains in conjunction with a dimensionless number that accounts for averaged polymer chain inhomogeneities. This coefficient is analogous to the dimensionless number, which successfully describes the asymmetry of both the Weibull distribution and of particle size distribution according to the Rosin, Rammler, Sperling and Bennet model. In comparison to earlier models based on time-superposition principles, the current approach enables lifetime prediction using a single short-term measurement, which must be taken at a properly chosen applied strain. The applicability of the new model in predicting the long-term behavior has been demonstrated by the analysis of the relaxation behavior of semi-crystalline bio-based fibers.     

Local structure of the MgxNixCoxCuxZnxO(x=0.2) entropy‐stabilized oxide: An EXAFS study

Entropy‐stabilized oxides (ESOs) provide an alternative route to novel materials discovery and synthesis. It is, however, a challenge to demonstrate that the constituent elements in an entropy‐stabilized crystal are homogeneously and randomly dispersed among a particular sublattice, resulting in a true solid solution with no evidence of local order or clustering. In this work, we present the application and analysis of extended X‐ray absorption fine structure (EXAFS) on the prototype ESO composition Mg_xNi_xCo_xCu_xZn_xO (x=0.2). In so doing, we can quantify the local atomic structure on an element‐by‐element basis. We conclude that local bond lengths between metal and oxygen vary around each absorbing cation, with notable distortion around the Cu–O polyhedra. By the second near neighbor (i.e., the cation‐cation pair), interatomic distances are uniform to the extent that the collected data can resolve. Crystal models that best fit the experimental scattering data include cations that are distributed randomly on an FCC sublattice with minimal positional disorder, with an interleaved FCC anion sublattice with oxygen ions displaced from the ideal locations to accommodate the distortions in the cation polyhedra. Density functional theory calculations of the ESO system yield a significant broadening in the positional distribution for the oxygen sublattice compared to that for the cation sublattice for all peaks, showing consistency with the conclusion from the experimental data that the distortion from an ideal rock salt structure occurs primarily through disorder in the oxygen sublattice.     

A framework for Chinese Power Games – Political tactics in information systems development processes

This paper explores the way one particular manager of the MIS department at TaiJen uses expert knowledge to adopt political tactics to achieve his goals of self-interest in information system development (ISD) processes. Based on qualitative data collected from TaiJen (pseudonym), the study interweaves Chinese Power Game: Face and Favor Theory and Confucian Relationalism into the different kinds of political tactics utilized by the MIS department manager. An appropriate categorization of political tactics is constructed based on two dimensions: “relatively strong/weak power” and “winning/losing position.” Nine kinds of political tactics are grouped into four types: aggression, defense, strengthening and withdrawal, and the different tactics used by the manager of the MIS department on his supervisors, equals and subordinates are categorized on the basis of these types. In view of the important role played by Asia in the 21st Century, particularly by Chinese cultural societies, which represent a hugely significant market to all global enterprises, it is hoped that this study will assist the business world in understanding the culture that places emphasis on the conducting of business through interpersonal relationships.     

How to build an appropriate information ethics code for enterprises in Chinese cultural society

Information ethics codes play a vital role in clarifying the responsibilities of MIS (management information systems) professionals and providing them with a point of reference when dealing with ethical issues. In view of the important 21st Century role played by China, particularly Mainland China, which represents a hugely significant market to all global enterprises, it is hoped that this study will assist the business world in understanding the culture in which Chinese business is conducted, and will facilitate the building of a suitable information ethics code in the future. Academically, this paper aims to explain how Confucian ethics and the guanxi ¹ culture perspective affect MIS professionals’ ethical dilemmas and reactive processes. Specifically, it examines the reactive processes of MIS professionals in CHSyst (pseudonym) in Taiwan, Hong Kong and Mainland China. In practice, this study provides a good reference for enterprises such as the above that wish to find the most appropriate way to create an ethics code suitable for a Chinese company context to prevent Chinese MIS professionals from behaving unethically in their workplace. Such a code will serve to reduce the negative consequences of unethical conduct for the organization.     

Rapid automated detection of roots in minirhizotron images

An approach for rapid, automatic detection of plant roots in minirhizotron images is presented. The problem is modeled as a Gibbs point process with a modified Candy model, in which the energy functional is minimized using a greedy algorithm whose parameters are determined in a data-driven manner. The speed of the algorithm is due in part to the selection of seed points, which discards more than 90% of the data from consideration in the first step. Root segments are formed by grouping seed points into piecewise linear structures, which are further combined and validated using geometric techniques. After root centerlines are found, root regions are detected using a recursively bottom-up region growing method. Experimental results from a collection of diverse root images demonstrate improved accuracy and faster performance compared with previous approaches.     

Exploring the impact of ethnic identity through other-generated cues on perceptions of spokesperson credibility

Although previous studies indicate that perceived similarity can influence perceptions of source credibility, less is known about the impact of ethnic identity on these perceptions in social media environments. A quasi-experiment was designed to manipulate the strength of ethnic identity of an African American spokesperson promoting a health news story. The results indicate a substantive condition by participant ethnicity interaction, in which African Americans assign greater credibility to high ethnic identity spokespeople, while Caucasian respondents found low ethnic identity spokespersons more credible. The results are discussed in terms of the understanding of credibility perceptions across diverse audiences, and the implications for health communication professionals working with historically underrepresented populations.     

Unmanned Aerial Vehicle Security Using Recursive Parameter Estimation

The proliferation of Unmanned Aerial Vehicles (UAVs) brings about many new security concerns. A common concern with UAV security is for an intruder to take control of a UAV, which leads for a need for a real time anomaly detection system. This research resulted in a prototype UAV monitoring system that captures flight data, and then performs real time estimation and tracking of the airframe and controller parameters. The aforementioned is done by utilizing the Recursive Least Squares Method (RLSM). Using statistical validation and trend analysis, parameter estimates are critical for the detection of cyber attacks and incipient hardware failures that can invariably jeopardize mission success. The results demonstrate that achieving efficient anomaly detection during flight is possible through the application of statistical methods to profile system behavior. The anomaly detection system that was designed can be performed in real time while the UAV is in flight, constantly verifying its parameters.