Tracing atmospheric nitrate deposition in a complex semiarid ecosystem using delta17O

The isotopic composition of nitrate collected from aerosols, fog, and precipitation was measured and found to have a large 17O anomaly with delta17O values ranging from 20 percent per thousand to 30% percent per thousand (delta17O = delta17O - 0.52(delta18O)). This 17O anomaly was used to trace atmospheric deposition of nitrate to a semiarid ecosystem in southern California. We demonstrate that the delta17O signal is a conserved tracer of atmospheric nitrate deposition and is a more robust indicator of N deposition relative to standard delta18O techniques. The data indicate that a substantial portion of nitrate found in the local soil, stream, and groundwater is of atmospheric origin and does not undergo biologic processing before being exported from the system.     

Korrosionsverhalten und Deckschichtbildung auf Kupfer und Kupferlegierungen

Corrosion Behaviour and Film Formation of Copper and Copper Alloys Film formation processes on Cu, CuZn, CuAl and CuNi materials in NH₃- and Cl^?-containing aqueous solutions are discussed in a summary article by way of corrosion systems, some typical and some of practical significance, and the protection offered by these films against general corrosion is described. Also considered are localized corrosion phenomena to which Cu-base alloys with oxide films are typically exposed. A comparison of the resistance of the various alloying systems illustrates the particular danger of stress corrosion cracking of mechanically stressed metals. Finally, the type and structure of oxide surface films are discussed with respect to their effect on crack initiation.     

Some comments on a Viennese school of psychiatry.

The author comments on a school of psychotherapy called Logotherapy or Existential Analysis, which was originated by Victor E. Frankl of the Department of Neurology and Psychiatry at the University of Vienna. This school of analysis reflects the culture of the Hitler era and post-war Europe. Frankl states that neurosis is caused by repression of the patient's sense of responsibility and the function of psychotherapy is to bring this sense of responsibility back to the patient's awareness. Happiness, he postulates, is a byproduct of the realization of other values. Fear of death, aging, and discomfort are the principal causes of anxiety. The author feels that this school of psychotherapy, which has arisen from an experiential background so different from ours is worthy of careful study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of assigned goal level and knowledge of results on arithmetic computation: A laboratory study.

Examined the effects of knowledge of results (KR) and assigned goals on arithmetic computation. 100 female university students either received or did not receive explicit KR while under an easy or challenging goal assignment. 50 controls received neither KR nor goal assignment. Ss receiving KR under challenging goal assignments significantly increased their computational speed at no apparent cost in accuracy. These findings are congruent with the findings of M. Erez (1977). With the minimizing of implicit KR in the no-KR groups in the present study, challenging goal assignment in itself had no noticeable effect on computational speed and led to a significant increase in errors. It is suggested that feedback may be a necessary complement to assigned goals in facilitating performance. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Schnellbestimmung monomerer,nicht oxidierter Fettsäuren

Quick Determination of Monomeric Unoxidized Fatty Acids Refining and distillation fatty acids as well as raw or partly refined oils can contain beside monomeric fatty acids di and polymeric as well as oxidized fatty acids, too. Determination of the content of monomeric, unoxidized fatty acids is important for the use in feed. As quick method a gas chromatographic procedure is presented. Collaborative studies demonstrate a satisfactory repeatability of the results. The comparability is impaired by apparatus and operating parameters. The relative constance of deviation permits a compensation by comparative analysis and determination of correction factors.     

Arcs-states models for the vehicle routing problem with time windows and related problems

This paper presents several Arcs-States models that can be applied to numerous vehicle routing problems, one of which is the well-known vehicle routing problem with capacities and time windows. In these models, the variables correspond to the states (i.e. the resource quantities) of the vehicles when they travel through an arc. The LP relaxation of the problem provides a lower bound that can be embedded in a branch and bound algorithm that solves the problem exactly. However, for the pseudo-polynomial number of variables and constraints of our models, column and row generations have to be used. Generally, in a branch and bound algorithm, the lower bound needs to be very efficient to minimize the size of the branch and bound trees as far as possible. One of the models we present, the time-only, relies on a relaxation of the Arcs-States model where a resource is removed from the states in the variables. Although the quality of the bounds decreases, the global resolution time is greatly improved, as illustrated on instances of Solomon's benchmark.