Determination of pesticides in the respirable fraction of airborne particulate matter by high-performance liquid chromatography–tandem mass spectrometry

Potential harmful effects of pesticides include risks to human health of workers involved in the wet spray application in cultivated areas. Inhalation exposure depends on several factors including pesticide concentrations in the respirable fraction of airborne particulate matter (PM4). To ensure a high level of protection, the use of tractors with cabins provides protection against dust, aerosols, and vapors. Since tractors not providing maximum protection are still in use, PM4 was sampled during spreading operations in agricultural fields inside and outside tractor cabins. Sample preparation technique based on accelerated solvent extraction and solid-phase extraction cleanup was optimized before analysis of nine pesticides in PM4. Meptyldinocap, deltamethrin, myclobutanil, fluopyram, methoxyfenozide, dimethomorph, fluopicolide, cyflufenamid, and metrafenone were simultaneously determined by high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC–ESI–MS–MS). The results demonstrated the efficacy of the tractor cabs used in the sampling sites. © 2017 Taylor & Francis

A new lower bound approach for single-machine multicriteria scheduling

The concept of maximum potential improvement has played an important role in computing lower bounds for single-machine scheduling problems with composite objective functions that are linear in the job completion times. We introduce a new method for lower bound computation; objective splitting. We show that it dominates the maximum potential improvement method in terms of speed and quality

Multiparty Quantum Communication Using Multiqubit Entanglement and Teleportation

We propose a 2N qubit entangled channel that can be used to teleport N qubits in a network to a single receiver. We describe the structure of this channel and explicitly demonstrate how the protocol works. The channel can be used to implement a scheme in which all parties have to participate in order for the teleportation to be successful. This can be advantageous in various scenarios and we discuss the potential application of this protocol to voting

Simple and insensitive bounds for a grading and an overflow model

Simple and intuitively obvious lower and upper bounds are suggested for a specific grading and an overflow model. The bounds are based on product-type modifications and are insensitive. Numerical support indicates a potential usefulness for quick engineering purposes

Reading with new tools: An evaluation of Personal Digital Assistants as tools for reading course materials

Lightweight, palmtop devices such as personal digital assistants (PDAs) can now be used for reading electronic text, opening up their potential as learning tools. This paper reports a study that evaluated the use of PDAs for reading course materials by students on an Open University master's course. The research is grounded in activity theory, which provides a useful framework for examining how the introduction of a new tool changes an existing activity. Student perceptions of the possibilities and constraints of the PDA, as determined by questionnaires and interviews, reveal the impact the new tool had upon reading. The PDA constrained reading with limitations such as the small screen size, new requirements for navigating through the text and awkward methods for taking notes. These conditions made it difficult for students to skim‐read the text, to move back and forth within the document and to interact with the text as easily as they could with paper. Nevertheless, students welcomed the opportunity to have the course materials on a portable, lightweight device that could be used at any time and in any place. This made it easier to fit the reading activity around the various other activities in which students were involved In addition, the PDA was used in conjunction with existing tools, such as the printed version of the course materials and the desktop computer. Therefore, it was not seen to replace paper but rather to extend and complement it. The findings are discussed using concepts from activity theory to interpret how the new tool modified the reading activity

Searching by approximate personal-name matching

We discuss the design, building and evaluation of a method to access theinformation of a person, using his name as a search key, even if it has deformations. We present a similarity function, the DEA function, based on the probabilities of the edit operations accordingly to the involved letters and their position, and using a variable threshold. The efficacy of DEA is quantitatively evaluated, without human relevance judgments, very superior to the efficacy of known methods. A very efficient approximate search technique for the DEA function is also presented based on a compacted trie-tree structure.Postprint (published version

The Mass of Graviton and Its Relation to the Number of Information according to the Holographic Principle

We investigate the relation of the mass of the graviton to the number of information in a flat universe. As a result we find that the mass of the graviton scales as gr ∝ 1/√. Furthermore, we find that the number of gravitons contained inside the observable horizon is directly proportional to the number of information ; that is, gr ∝ . Similarly, the total mass of gravitons that exist in the universe is proportional to the number of information ; that is, gr ∝ √. In an effort to establish a relation between the graviton mass and the basic parameters of the universe, we find that the mass of the graviton is simply twice the Hubble mass as it is defined by Gerstein et al. (2003), times the square root of the quantity − 1/2, where is the deceleration parameter of the universe. In relation to the geometry of the universe we find that the mass of the graviton varies according to the relation gr ∝ √sc, and therefore gr obviously controls the geometry of the space time through a deviation of the geodesic spheres from the spheres of Euclidean metric