The Hertz Corporation

About: The Hertz Corporation is a based out in . It is known for research contribution in the topics: Population & Soil water. The organization has 9562 authors who have published 11044 publications receiving 447929 citations. The organization is also known as: Hertz Rental Car & Hertz Rent-a-Car.

Cloning and analysis of the esterase genes conferring insecticide resistance in the peach-potato aphid, Myzus persicae (Sulzer).

Abstract: Full-length cDNA clones encoding the esterases (E4 and FE4) that confer insecticide resistance in the peach-potato aphid [Myzus persicae (Sulzer)] were isolated and characterized. The E4 cDNA contained an open reading frame of 1656 nucleotides, coding for a protein of 552 amino acids. The FE4 cDNA shared 99% identity with E4 over this region, the most important difference being a single nucleotide substitution resulting in the FE4 mRNA having an extra 36 nucleotides at the 3' end. The derived amino acid sequences for the N-terminus of E4 and FE4 were identical, with the first 23 residues being characteristic of a signal peptide and the next 40 residues being an exact match to the N-terminal sequence determined by Edman degradation of both purified proteins. The predicted molecular masses of 58.8 and 60.2 kDa for the E4 and FE4 polypeptides were consistent with those previously observed by in vitro translation of mRNA. Five potential N-linked glycosylation sites were present in both polypeptides, in accordance with earlier evidence that the native esterases are glycoproteins. Comparison of the aphid esterase protein sequences with other serine hydrolases provided evidence that their activity involves a charge-relay system with a catalytic triad the same as that found in acetylcholinesterase. Restriction mapping and sequencing of cloned genomic DNA showed that the E4 gene is spread over 4.3 kb with six introns and that the previously reported differences between the 3' ends of the E4 and FE4 genes result from single nucleotide substitutions and not gross differences in the DNA sequences.

A comprehensive method of rock mass characterization for indicating natural slope instability

Abstract: The purpose of this paper is to present an application of the Rock Engineering Systems (RES) methodology for developing a new rock mass classification, sensitive to large-scale instability in natural slopes and suitable for indicating critical sites In the area under study, located in the Italian Central Alps, and in most natural slopes, analysis is complicated by lack of data, geological complexity, scale of the instability phenomena and the high number of interacting factors In order to be able to have a structured approach to such complexity, a comprehensive method based on the RES approach was adopted This is an objective-based approach which allows the utilization of all the information related to the project, tailoring the classification to the actual circumstances Hence those parameters which are particularly active at the site can be evaluated and the importance of their interactions established Following this approach, 19 parameters relating to the general environment and to the rock mass characteristics are considered Their reciprocal causes and effects are analysed in order to weight each parameter according to its degree of interactivity in the system The final definition of the rock mass instability index takes into account the variability of the parameter values for different slopes in assigning ratings to different classes of parameter values In parallel, a predictability rating is computed, according to the presence in the field of a number of ‘indicators of instability’ Both indices allow discrimination of critical slopes, and are in good agreement with field evidence demonstrating the value of the approach

Phase Diagrams of Triglyceride Systems

Abstract: Publisher Summary This chapter presents phase diagrams of triglyceride systems. Triglycerides form an important group of natural products, as they provide the energy source in many of our foodstuffs. Mixtures of triglycerides similar in melting points form solid solutions over extensive ranges of composition. This leads to several types of phase behavior, eutectic formation being the most common, although peritectics and monotectics are also formed. The chapter reviews the systems involving only simple (mono-acid) triglycerides, systems of mixed-acid triglycerides, ternary mixtures of triglycerides, and systems with partial glycerides. Mono-acid triglycerides are the easiest to study, as they can be readily obtained in high purity, especially in the case of the saturated compounds that are not sensitive to atmospheric oxidation. The heat of fusion of one of the components of the mixtures can sometimes be calculated from the results with the help of the Hilde-brand solubility equation, and wherever this is done, the values obtained are compared with calorimetric ones.

A suction trap for small airborne insects which automatically segregates the catch into successive hourly samples

Abstract: This paper describes the design and operation of a suction trap which takes in air at a constant rate in winds up to 12 m.p.h. The catch is deposited in a collecting tube into which closely fitting disks fall, one every hour, thus segregating the catch into successive hourly samples. The trap is electrically driven; it operates in all weathers and heavy rain does not disorganize the catch.