Luminescence of SrAl<Subscript>2</Subscript>O<Subscript>4</Subscript>:Cr<Superscript>3+</Superscript>

Samples of SrAl₂O₄ and SrAl₂O₄:Cr³⁺ were prepared by mixing the powder materials SrCO₃, Al₂O₃, and Cr₂O₃. The crystal structures of the undoped and doped samples were analyzed by X-ray diffraction (XRD) measurements. The diffraction patterns reveal a dominant phase, characteristic of the monoclinic SrAl₂O₄ compound and another unknown secondary phase, in small amount, for doped samples. The data were fitted using the Rietveld method for structural refinements and lattice parameter constants (a, b, c, and β) were determined. Luminescence of Cr³⁺ ions in this host is investigated for the first time by excitation and emission spectroscopy at room temperature. Emission spectra present a larger band and a smaller structure associated to the and electronic transitions, respectively. The obtained results are analyzed by crystal-field theory and the crystal-field parameter, Dq, and Racah parameters, B and C, are determined from the excitation measurements.     

The additional dose to radiosensitive organs caused by using under-collimated X-ray beams in neonatal intensive care radiography

Radiographic technique and exposure parameters were recorded in five Israeli Neonatal Intensive Care Units for chest, abdomen and both chest and abdomen X-ray examinations. Equivalent dose and effective dose values were calculated according to actual examination field size borders and proper technique field size recommendations using PCXMC, a PC-based Monte Carlo program. Exposure of larger than required body areas resulted in an increase of the organ doses by factors of up to 162 (testes), 162 (thyroid) and 8 (thyroid) for chest, abdomen and both chest and abdomen examinations, respectively. These exposures increased the average effective dose by factors of 2.0, 1.9 and 1.3 for the chest, abdomen and both chest and abdomen examinations, respectively. Differences in exposure parameters were found between the different neonatal intensive care units-tube voltage, current-time product and focal to skin distance differences up to 13, 44 and 22%, respectively. Reduction of at least 50% of neonate exposure is feasible and can be implemented using existing methodology without any additional costs.     

Rod-shaped nanocrystals elicit neuronal activity in vivo

The development of novel nanomaterials has raised great interest in efforts to evaluate their effect on biological systems, ranging from single cells to whole animals. In particular, there exists an open question regarding whether nanoparticles per se can elicit biological responses, which could interfere with the phenomena they are intended to measure. Here it is reported that challenging the small cnidaria Hydra vulgaris in vivo with rod-shaped semiconductor nanoparticles, also known as quantum rods (QRs), results in an unexpected tentacle-writhing behavior, which is Ca(2+) dependent and relies on the presence of tentacle neurons. Due to the absence of surface functionalization of the QRs with specific ligands, and considering that spherical nanoparticles with same composition as the QRs fail to induce any in vivo behavior on the same experimental model, it is suggested that unique shape-tunable electrical properties of the QRs may account for the neuronal stimulation. This model system may represent a widely applicable tool for screening neuronal response to nanoparticles in vivo.     

Prevention of travel-related foodborne diseases: Microbiological risk assessment of food handlers and ready-to-eat foods in northern Italy airport restaurants

The focus of this study was to assess the hygienic standards of 44 foodservice facilities located in three Italian International Airports (with an output ranging from 100 to 800 meals a day), by monitoring the microbiological quality and safety of foods ready for consumption (n = 773), food contact surfaces (n = 302), and food handlers (n = 287). The hygienic standard of surfaces was sufficiently high. Only 7.9% of surfaces did not conform with advisory standards in terms of total coliforms, and 2.6% were found to be contaminated with Enterococcus spp. at ≥1.0 log₁₀ CFU/cm². The hygienic standard of washed and disinfected hands of food workers was not adequately high: the total bacterial count and coagulase positive Staphylococci exceeded the satisfactory limit in 8.4% and 3.5% of cases, respectively. The microbial analysis of foods examined showed an absence of Listeria monocytogenes and Salmonella spp. Food sample analyses highlighted a percentage of samples that did not conform to microbial reference standards: Staphylococcus aureus non-conforming percentages ranged from 2.3% for “fully cooked food” to 9.2% for “raw fruit and vegetables”; Escherichia coli, from 0.0% for “raw fruit and vegetables” to 6.1% for “cooked and uncooked foods”; total coliforms from 14.3% for “fully cooked food” to 79.8% for “cooked and uncooked food”. In conclusion, the results suggest that more effort is needed in the application of HACCP principles. In order to prevent travel-related foodborne infections, various changes in the timing of food preparation and holding temperatures are needed, together with further training of food handlers.     

MR imaging of the prostate in clinical practice

Magnetic resonance imaging (MRI) is the imaging tool of choice in the evaluation of prostate cancer. The main applications of MR imaging in the management of prostate cancer are: (1) to guide targeted biopsy when prostate cancer is clinically suspected and previous ultrasound-guided biopsy results are negative; (2) to localize and stage prostate cancer and provide a roadmap for treatment planning; and (3) to detect residual or locally recurrent cancer after treatment. Other MR techniques such as proton MR spectroscopic imaging (MRSI), diffusion-weighted imaging (DWI), and contrast-enhanced MRI (CE-MRI) complement conventional MR imaging by providing metabolic and functional information that can improve the accuracy of prostate cancer detection and characterization. In everyday clinical practice, and to account for patient comfort, MR imaging studies are limited to 1 h. To obtain consistently high-quality images, a well-designed protocol is necessary. Routine MR imaging can be supplemented by other MR techniques such as MRSI, DWI or CE-MRI depending on the expertise available and the clinical questions that need to be answered. This review summarizes the role of MR imaging in the management of prostate cancer and describes practical approaches to implementing anatomic, metabolic and functional MR imaging techniques in the clinic.     

并行工程中的模糊知识(信息)协同方法研究

在文献［１］的基础上进一步讨论了基于模糊集理论的知识协同处理算法。文中提出的算法体现了权威性和民主性相结合的原则，并对提出的算法的灵敏度进行了理论上的分析。通过实例分析，提出的算法具有较强的实用性和良好的效果，易为各个知识源所接受。     

Toward achieving multidisciplinary professional collaboration.

The complexity of the clinical, educational, and research situations confronting the health care provider suggests the need for collaboration among professionals. Psychologists, advanced practice nurses, and physicians will have to interface continuously to provide accessible quality care at an affordable price. Intra-, inter-, and multidisciplinary types of collaboration are defined, and characteristics of collaborative clinical, educational, and research endeavors are noted. A community partnership for prenatal care, a rural interdisciplinary training program, and a Department of Defense psychopharmacology training project are described. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mining top-K frequent itemsets from data streams

Frequent pattern mining on data streams is of interest recently. However, it is not easy for users to determine a proper frequency threshold. It is more reasonable to ask users to set a bound on the result size. We study the problem of mining top K frequent itemsets in data streams. We introduce a method based on the Chernoff bound with a guarantee of the output quality and also a bound on the memory usage. We also propose an algorithm based on the Lossy Counting Algorithm. In most of the experiments of the two proposed algorithms, we obtain perfect solutions and the memory space occupied by our algorithms is very small. Besides, we also propose the adapted approach of these two algorithms in order to handle the case when we are interested in mining the data in a sliding window. The experiments show that the results are accurate.

A hybridization of mathematical programming and dominance-driven enumeration for solving shift-selection and task-sequencing problems

A common problem in production planning is to sequence a series of tasks so as to meet demand while satisfying operational constraints. This problem can be challenging to solve in its own right. It becomes even more challenging when higher-level decisions are also taken into account. For example, determining which shifts to operate clearly impacts how tasks are then scheduled; additionally, reducing the number of shifts that must be operated can have great cost benefits. Integrating the shift-selection and task-sequencing decisions can greatly impact tractability, however, traditional mathematical programming approaches often failing to converge in reasonable run times. Instead, we develop an approach that embeds mathematical programming, as a mechanism for solving simpler feasibility problems, within a larger search-based algorithm that leverages dominance to achieve substantial pruning. In this paper, we introduce the Shift-Selection and Task Sequencing problem (SS-TS), develop the Test-and-Prune algorithm (T&P), and present computational experiments based on a real-world problem in automotive stamping to demonstrate its effectiveness. In particular, we are able to solve to provable optimality, in very short run times, a number of problem instances that could not be solved through traditional integer programming methods.