Corridors for movement of organisms between refuges are confounded with corridors designed for other functions, obscuring an assessment of cost‐effectiveness. The rationales for movement corridors are (1) to lower extinction rate in the sense of the equilibrium theory, (2) to lessen demographic stochasticity, (3) to stem inbreeding depression, and (4) to fulfill an inherent need for movement. There is a paucity of data showing how corridors are used and whether this use lessens extinction by solving these problems. Small, isolated populations need not be doomed to quick extinction from endogenous forces such as inbreeding depression or demographic stochasticity, if their habitats are protected from humans. In specific instances, corridors could have biological disadvantages. Corridor proposals cannot be adequately judged generically. In spite of weak theoretical and empirical bases, numerous movement corridor projects are planned. In the State of Florida, multi‐million‐dollar corridor proposals are unsupported by data on which species might use the corridors and to what effect. Similarly, plans for massive corridor networks to counter extinction caused by global warming are weakly supported. Alternative approaches not mutually exclusive of corridors might be more effective, but such a judgment cannot be made without a cost‐benefit analysis.

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A severe stem rust epidemic occurred in southern Ethiopia during November 2013 to January 2014, with yield losses close to 100% on the most widely grown wheat cultivar, 'Digalu'. Sixty-four stem rust samples collected from the regions were analyzed. A meteorological model for airborne spore dispersal was used to identify which regions were most likely to have been infected from postulated sites of initial infection. Based on the analyses of 106 single-pustule isolates derived from these samples, four races of Puccinia graminis f. sp. tritici were identified: TKTTF, TTKSK, RRTTF, and JRCQC. Race TKTTF was found to be the primary cause of the epidemic in the southeastern zones of Bale and Arsi. Isolates of race TKTTF were first identified in samples collected in early October 2013 from West Arsi. It was the sole or predominant race in 31 samples collected from Bale and Arsi zones after the stem rust epidemic was established. Race TTKSK was recovered from 15 samples from Bale and Arsi zones at low frequencies. Genotyping indicated that isolates of race TKTTF belongs to a genetic lineage that is different from the Ug99 race group and is composed of two distinct genetic types. Results from evaluation of selected germplasm indicated that some cultivars and breeding lines resistant to the Ug99 race group are susceptible to race TKTTF. Appearance of race TKTTF and the ensuing epidemic underlines the continuing threats and challenges posed by stem rust not only in East Africa but also to wider-scale wheat production.

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Different approaches to enhancement of electrocatalytic activity of noble metal nanoparticles during oxidation of small organic molecules (namely potential fuels for low-temperature fuel cells such as methanol, ethanol and formic acid) are described. A physical approach to the increase of activity of catalytic nanoparticles (e.g. platinum or palladium) involves nanostructuring to obtain highly dispersed systems of high surface area. Recently, the feasibility of enhancing activity of noble metal systems through the formation of bimetallic (e.g. PtRu, PtSn, and PdAu) or even more complex (e.g. PtRuW, PtRuSn) alloys has been demonstrated. In addition to possible changes in the electronic properties of alloys, specific interactions between metals as well as chemical reactivity of the added components have been postulated. We address and emphasize here the possibility of utilization of noble metal and alloyed nanoparticles supported on robust but reactive high surface area metal oxides (e.g. WO3, MoO3, TiO2, ZrO2, V2O5, and CeO2) in oxidative electrocatalysis. This paper concerns the way in which certain inorganic oxides and oxo species can act effectively as supports for noble metal nanoparticles or their alloys during electrocatalytic oxidation of hydrogen and representative organic fuels. Among important issues are possible changes in the morphology and dispersion, as well as specific interactions leading to the improved chemisorptive and catalytic properties in addition to the feasibility of long time operation of the discussed systems.

IThis report, as submitted by the contractor, has been cleared for felease to Defense Technical I nfor motion center (DTIC) to comply with regulatory requirements. It has been given n rmr itiuinohrta oDI S r i e ( T S . T e v w s i n n a n l fnin g c o n t a n e d i n o i p r a r e d s r th o o t h e r anut or I n and will be available only through DIC or other reference services such as the National Technical information j hould not be cnruJaanoicaOptetofheAmy position, policy, or decision, unless so designated by rother official documentation. .. ';_' UNCLASSIFIED SECURITY CLASSIFICATION OF TI41S PAGE (When Data Entered) -_ REPORT DOCUMENTATION PAGE READ INSTRUCTIONS BEFORE COMPLETING FORM . REPORT NUMBER J2. GOVT ACCESSION NO, S. RECIPIENT'S CATALOG NUMBER ARI Research Note 88-451 7... TITLE (and Subtitle) S. TYPE OF REPORT A PERIOD COVEREDThis research note reports on two studies run to determine whether the interpretations of statements, or forecasts, using vague probability and frequency expressions such as "likely", "improbable","frequently", "rarely" were sensitiv. to the base rates of the events involved. In the first experiment, professional weather forucasters judged situations drawn from a medical context. In the second, students judged matched forecast scenarios of common semantic content that differed only in prior probability (as determined by an independent group (OVER) O t D 3 E L-nO OF I NOV 65 IS OBSOLETE JAN 73UNCLASSIFIED) SECURITY CLASSIFtCATfOR OF THIS PAGE (When Date Entered)

The present review discusses some current issues related to the principles and analytical aspects of electrochemical studies (typically done at room temperature) of solid, rigid or semirigid (nonfluid) systems in the absence of a liquid solution phase. Representative examples include redox and conducting organic polymers, melts and solid solutions of redox centers in solid ionic conductors, mixed-valence polynuclear inorganic materials, transition metal salts, oxides, and zeolites. The emphasis is on the elements of dynamics for the efficient delivery of charge and on reactivity of the 'redox conducting' materials. The effective (apparent) diffusional mechanism is critical to the success of most analytical measurements in solidstate. Also described are typical electrochemical cells and experimental tactics to overcome the relatively slow dynamics of transport in solid (nonfluid) systems. Application of microdimensional electrodes leads to an improvement in the quality of solid-state electrochemical data and provides new diagnostic and analytical possibilities. Results of mechanistic studies, which are relevant to the development of novel analytical methods, together with trends towards possible future applications also are discussed.

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