Polypyrroles as antioxidants: Kinetic studies on reactions of bilirubin and biliverdin dimethyl esters and synthetic model compounds with peroxyl radicals in solution. Chemical calculations on selected typical structures

Rate constants for hydrogen-atom transfer (HAT) from bilirubin dimethyl ester (BRDE) and biliverdin dimethyl ester (BVDE) to peroxyl radicals during inhibited autoxidation of styrene initiated by azobisisobutyronitrile (AIBN) were kinh(BRDE) = 22.5 ×4 and kinh(BVDE) = 10.2 × 104 M-1 s-1, and the stoichiometric factors (n) were 2.0 and 2.7, respectively. A synthetic tetrapyrrole (bis(dipyrromethene)) containing the α-central (2,2′) CH2 linkage gave kin

Testing a global standard for quantifying species recovery and assessing conservation impact.

Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a "Green List of Species" (now the IUCN Green Status of Species). A draft Green Status framework for assessing species' progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species' viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species' recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard

Involvement of basolateral amygdala GABAA receptors in the effect of dexamethasone on memory in rats*

In this study we investigated whether GABAA receptors of the basolateral amygdala (BLA) interact with the effect of dexamethasone on the retrieval stage of memory. Adult male Wistar rats were bilaterally cannulated in the BLA by stereotaxic surgery. The animals were trained in step-through apparatus by induction of electric shock (1.5 mA, 3 s) and were tested for memory retrieval after 1 d. The time of latency for entering the dark compartment of the instrument and the time spent by rats in this chamber were recorded for evaluation of the animals’ retrieval in passive avoidance memory. Administration of dexamethasone (0.3 and 0.9 mg/kg, subcutaneously (s.c.)), immediately after training, enhanced memory retrieval. This effect was reduced by intra-BLA microinjection of muscimol (0.125, 0.250 and 0.500 µg/rat), when administered before 0.9 mg/kg of dexamethasone. Microinjection of bicuculline (0.75 µg/rat, intra-BLA) with an ineffective dose of dexamethasone (0.1 mg/kg, s.c.) increased memory retrieval. However, the same doses of muscimol and bicuculline without dexamethasone did not affect memory processes. Our data support reports that dexamethasone enhances memory retrieval. It seems that GABAA receptors of the BLA mediate the effect of dexamethasone on memory retrieval in rats

Análise estrutural e considerações sobre a dinâmica sucessional de dois fragmentos florestais semideciduais do Jardim Botânico Municipal de Bauru, SP, Brasil Structural analysis and considerations on the successional dynamic of two semideciduous forest fragments at the Municipal Botanical Garden of Bauru, SP, Brazil

Parâmetros fitossociológicos, como freqüência de classes de altura e de diâmetro, são muito utilizados em inferências sobre sucessão secundária em fitocenoses. Indivíduos abustivo-arbóreos com no mínimo 1,5 m de altura e fuste a 1,3 m, foram amostrados em 2.600 m² de floresta estacional semidecidual do Jardim Botânico Municipal de Bauru (JBMB). Informações sobre as freqüências de classes de diâmetro das cinco espécies com maior índice de valor de importância (Ocotea pulchella, Protium heptaphyllum, Copaifera langsdorffii, Platypodium elegans e Trichilia pallida) e a classificação sucessional das populações mais numerosas também foram analisadas para inferências sobre as características sucessionais da comunidade estudada. As freqüências de classes de diâmetro de Vochysia tucanorum, espécie típica de savana, também foi estudada. As informações obtidas permitiram considerar que a floresta do JBMB encontra-se em estádio sucessional intermediário, e que, embora tenha sofrido com a ação do fogo no passado, algumas dessas populações estão conseguindo renovar-se.<br>Phytosociological parameters, as the frequency of height and diameter classes, are commonly used to make inferences about secondary succession in given phytocenoses. Shrub and tree individuals higher than 1.5 m and with a bole length of at least 1.3 m were sampled in 2,600 m2 of semideciduous seasonal forest in the Municipal Botanical Garden of Bauru (JBMB). Information on the diameter class frequencies of five species with the highest Importance Value Index (Ocotea pulchella, Protium heptaphyllum, Copaifera langsdorffii, Platypodium elegans and Trichilia pallida) and the more numerous species' successional classification were analyzed to make inferences about the successional features of the studied community. The diameter class frequencies of savannic species Vochysia tucanorum were also studied. The information obtained allowed to consider that the forest of the JBMB is at an intermediate successional stage, and that, although it used to be periodically burnt, some of its populations are able to renew themselves