How to make use of unlabeled observations in species distribution modeling using point process models

1. Species distribution modeling, which allows users to predict the spatial distribution of species with the use of environmental covariates, has become increasingly popular, with many software platforms providing tools to fit such models. However, the species observations used can have varying levels of quality and can have incomplete information, such as uncertain or unknown species identity.
2. In this paper, we develop two algorithms to classify observations with unknown species identities which simultaneously predict several species distributions using spatial point processes. Through simulations, we compare the performance of these algorithms using 7 different initializations to the performance of models fitted using only the observations with known species identity.
3. We show that performance varies with differences in correlation among species distributions, species abundance, and the proportion of observations with unknown species identities. Additionally, some of the methods developed here outperformed the models that did not use the misspecified data. We applied the best‐performing methods to a dataset of three frog species (Mixophyes).
4. These models represent a helpful and promising tool for opportunistic surveys where misidentification is possible or for the distribution of species newly separated in their taxonomy.

     

Determination of monoamines in brain nuclei by high performance liquid chromatography with electrochemical detection : Young vs. middle aged rats

A previously described high performance liquid chromatographic method for simultaneously measuring norepinephrine, dopamine, serotonin and 5-hydroxyindole acetic acid has been modified to permit analysis of the monoamines in microdissected brain nuclei from a single rat. Results of measurements in 12 nuclei of young and middle aged male rats are presented.     

Correction to: Reproductive traits of two species of suckermouth armored catfishes (Siluriformes: Loricariidae) from a coastal drainage in the southern limits of the Atlantic Forest,Brazil

Environmental Biology of Fishes -     

Anticlastogenic effect of beta-carotene in Chinese hamsters. Time and dose response studies with different mutagens

beta-Carotene exhibited dose-dependent anticlastogenic effects on aberrations induced by the direct-acting mutagens thio-TEPA, methyl methanesulfonate and busulfan in the in vivo chromosome aberration test (bone marrow cells, Chinese hamsters). No effect was seen when retinol was used. Apparent differences in the action of beta-carotene on aberrations induced by the three applied mutagens may be due to differences in the solubility of the compounds and to the different routes of administration.     

Effects of Pentachloronitrobenzene and Some of Its Known and Possible Metabolites on Fungi

Fungicidal activities of pentachloronitrobenzene and derivatives were tested with Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, Trichophyton mentagrophytes, and Microsporon canis. In relation to pentachloronitrobenzene, no increasing fungistatic activities were found with cysteine derivatives. Rising fungistatic activities were seen with pentachlorophenylmethylsulfone and, in some of the strains, with pentachloronitrosobenzene, pentachlorothiophenol, pentachlorophenol, pentachloroaniline, pentachlorophenylmethylsulfoxide, the isomeric tetrachloronitrobenzenes, tetrachlorothiophenols, tetrachlorophenols, and tetrachloroanilines.