Optimizing Diversity Assessment Protocols for High Canopy Ants in Tropical Rain Forest

The canopies of tropical rain forests support highly diverse, yet poorly known, animal and plant communities. It is vital that researchers who invest the time needed to gain access to the high canopy are able efficiently to survey the animals and plants that they find there. Here, we develop diversity assessment protocols for one of the most ecologically important canopy animal groups, the ants, in lowland dipterocarp rain forest in Sabah, Malaysia. We design and test a novel trap (the purse‐string trap) that can be remotely collected, thus avoiding disturbance to ants. We compare this modified trap with two other methods for surveying canopy ants: precision insecticide fogging and baited pitfall trapping. In total, we collected 39,351 ants belonging to 173 species in 38 genera. Fogging collected the most individuals and species, followed by purse‐string trapping with baited pitfall trapping catching the fewest. Fogging also resulted in samples with a different species composition to purse‐string trapping and baited pitfall trapping, which were not different from one another. Using a ‘greedy algorithm’, which guides the selection of inventory methods in order to maximize new species discovered per researcher‐hour, we show that projects allocating fewer than 132 researcher‐hours to canopy ant collection and identification should sample exclusively using fogging. Those with more time should use a combination of methods. This prioritization technique could be used to accelerate species discovery in future rapid biodiversity assessments. Abstract in Malay is available in the online version of this article.     

Tricyclic antidepressants exhibit variable pharmacological profiles at the α2A adrenergic receptor

Antidepressant mechanisms of action remain shrouded in mystery, greatly hindering our ability to develop therapeutics which can fully treat patients suffering from depressive disorders. In an attempt to shed new light on this topic, we have undertaken a series of studies investigating actions of tricyclic antidepressant drugs (TCAs) at the α_2A adrenergic receptor (AR), a centrally important receptor, dysregulation of which has been linked to depression. Our previous work established a particular TCA, desipramine, as an arrestin-biased α_2AAR ligand driving receptor endocytosis and downregulation but not canonical heterotrimeric G protein-mediated signaling. The present work is aimed at broadening our understanding of how members of the TCA drug class act at the α_2AAR, as we have selected the closely related but subtly different TCAs imipramine and amitriptyline for evaluation. Our data demonstrate that these drugs do also function as direct arrestin-biased α_2AAR ligands. However, these data reveal differences in receptor affinity and in the extent/nature of arrestin recruitment to and endocytosis of α_2AARs. Specifically, amitriptyline exhibits an approximately 14-fold stronger interaction with the receptor, is a weaker driver of arrestin recruitment, and preferentially recruits a different arrestin subtype. Extent of endocytosis is similar for all TCAs studied so far, and occurs in an arrestin-dependent manner, although imipramine uniquely retains a slight ability to drive α_2AAR endocytosis in arrestin-null cells. These findings signify an important expansion of our mechanistic understanding of antidepressant pharmacology, and provide useful insights for future medicinal chemistry efforts.     

Increased alertness behavior in Australian fur seals (Arctocephalus pusillus doriferus) at a high vessel traffic haul-out site

Vessel impacts on marine mammals are of growing concern, and marine mammals in urbanized marine environments are at particular risk of exposure. Port Phillip Bay (Victoria, Australia) is one such environment, in which Australian fur seals (AUFS; Arctocephalus pusillus doriferus) haul-out to rest, yet little is known about the impacts of vessels on resting seals. We used remote camera traps to investigate the influence of vessel traffic on AUFS behavior at a nonbreeding haul-out site. Environmental, temporal, and vessel-related variables were all associated with changes in AUFS alertness at this site. All vessel types elicited increased alertness above base-line levels (25%), with recreational and commercial motorized vessels associated with a 5.7%–10.8% increase in alertness. Unidentified vessels, the government vessel, and kayaks were associated with significantly increased alertness of 21.7%, 46.4%, and 60.7%, respectively, though accounted for only 6.2% of vessel observations. Vessels breaching current approach regulations (<5 m) showed a 32% increase in alertness, significantly higher than nonbreach approaches. Partial and complete flushing of the platform was rare, occurring in 1.0% of images analyzed. These results suggest that vessels do elicit a response from AUFS at this haul-out site, and that further monitoring of vessel activity and compliance is required.     

Effects of hydroxysafflor yellow A on ALDH1: Inhibition kinetics and molecular dynamics simulation

Hydroxysafflor yellow A (HSYA) is a potent natural antioxidant that displays important neuroprotective activity. Inhibition of acetaldehyde dehydrogenase 1 (ALDH1) has attracted the attention of researchers due to its overexpression in several types of cancers. We studied the effects of HSYA on ALDH1 by evaluating the inhibitory kinetics based on its antioxidant properties and performing computational simulation integrating methods. HSYA reversibly inhibited human recombinant ALDH1 via non-competitive inhibition (K_i = 0.267 ± 0.024 mM). We also investigated the tertiary structural changes via measuring intrinsic and ANS-binding fluorescence. The results indicated that the inactivation induced by HSYA was associated with structural changes. To obtain further information, we simulated the 3D structure of ALDH1 and conducted computational docking simulations as well as molecular dynamics simulations. The results indicated that 4 rings of HSYA interact with several residues near the ALDH1 active site. Our study provides insight into the inhibition of ALDH1 accompanied by structural changes. Based on its ALDH1-inhibiting effect and its potential as a natural antioxidant, HSYA is a potential agent for treating ALDH1-associated cancers.     

Using a general index approach to analyze camera-trap abundance indices

The lack of variance estimates constrain the utility of abundance indices calculated from camera-trap data. We adapted a General Index model, which allows variance estimation, to analyze camera-trap observations of feral pigs (Sus scrofa) for population monitoring in a tropical rainforest. We tested whether the index would respond to population manipulation, and found that it decreased by 57% following removal of 24 pigs and remained low in the following period. Our method is useful for monitoring other large animals in difficult landscapes, and the model can be used to enhance the value of existing data sets. © 2011 The Wildlife Society.     

Thermoluminescence of mercaptoethanol‐capped ZnS:Mn nanoparticles

The thermoluminescence (TL) of nanoparticles has become a matter of keen interest in recent times but is rarely reported. This article reports the synthesis of ZnS:Mn nanocrystals using a chemical route, with mercaptoethanol (ME) as the capping agent. The particle sizes for the nanocrystals were measured by X‐ray diffraction (XRD) and also by studying transmission electron microscopy (TEM) patterns. The particle sizes of the synthesized samples were found to be between 1 and 3 nm. For samples with different concentrations of the capping agent, it was found that the TL intensity of the ZnS:Mn nanoparticles increased as the particle size decreased. A shift in the peak position of the TL glow curve was also seen with decreasing particle size. The TL intensity was found to be maximal for samples with 1.2% of Mn. A change in the peak position was not found for samples with different concentrations of Mn. The half‐width glow peak curve method was used to determine the trap‐depth. The frequency factor of the synthesized samples was also calculated. The stability of the charge carriers in the traps increases with decreasing nanoparticle size. The higher stability may be attributed to the higher surface/volume ratio and also to the increase in the trap‐depth with decreasing particle size. Copyright © 2014 John Wiley & Sons, Ltd.     

The rare flavone isoetin as a yellow flower pigment in Heywoodiella oligocephala and in other Cichorieae

Isoetin (5,7,2′,4′,5′-pentahydroxyflavone) has been identified as a yellow flower pigment in Heywoodiella oligocephala, Hieracium pilosella and Hispidella hispanica. It also occurs in leaves of these plants and of 15 other taxa of the Cichorieae. It is restricted to three of the eight subtribes, occurring most characteristically in the Leontodontinae (in 5 of 7 genera surveyed). Isoetin is frequently accompanied by apigenin, luteolin, and scutellarein derivatives in these plants.     

European Stone Fruit Yellows: A Mark,Release and Recapture Experiment Tracking the Dispersal of its Vector Cacopsylla pruni (Hemiptera: Psyllidae) in a Model Apricot Orchard and Epidemiological Studies in Lower Austria

During the last 15 years, European stone fruit yellows (ESFY) has become a major concern in Austrian fruit production. Therefore, presence and temporal dynamics of its vector Cacopsylla pruni were investigated using a beating tray method and yellow sticky traps on Prunus armeniaca, Prunus domestica, Prunus spinosa and P. cerasifera nigra. Infection rates of C. pruni and Prunus spp. trees were assessed by direct, nested and real‐time PCR. Movement of remigrants in a model apricot orchard was tracked by aid of a mark, release and recapture study. Insects were marked by fluorescent dyes. Movement of the marked insects and presence of naturally occurring insects were monitored by yellow sticky traps. In 2011, remigration of C. pruni to Prunus spp. started in calendar week 10 (8th of March) and in 2012, in calendar week 12 (18th of March). Remigrants were observed until calendar week 20 (middle of May), significant numbers of the springtime generation adults were present until week 26 (end of June). The phytoplasma was ascertained in 0–11.5% of the remigrants and in 0–3.44% of the springtime generation insects. About 9.8–63.3% of the apricot samples, 20–40% of the plum samples and single blackthorn samples were infected. The mark, release and recapture study proved a fast and frequent tree‐to‐tree movement of remigrated C. pruni adults. Insects easily covered distances from row to row or even farther (ca. 13 m) within 24 h after release and were present in a large part of the model orchard after 8 days (up to 24 m from release point).     

Behavioural and electrophysiological responses of females of two species of tabanid to volatiles in urine of different mammals

Urine volatiles from different ungulates (cows, horses and sheep) were tested as bait for tabanids in southeastern France using Nzi traps during the early summer of 2011. Tabanus bromius Linnaeus, 1758 and Atylotus quadrifarius (Loew, 1874) (both: Diptera: Tabanidae) were the most captured species, respectively representing 57% and 41% of all tabanids collected (all of which were female). Horse urine significantly increased catches of T. bromius (1.6‐fold) and A. quadrifarius (3.5‐fold), and sheep urine significantly increased catches of A. quadrifarius (2.5‐fold). In parallel, an electroantennogram (EAG) study was conducted for the first time on these two species, in which EAGs were recorded using 1‐octen‐3‐ol and extracts of the same urine samples used in the field. For T. bromius, the EAG response to 1‐octen‐3‐ol increased quasi‐sigmoidally with dose, with a maximum response at ≥100 µg on filter paper. For both species of tabanid, cow and horse urine elicited larger EAGs than did sheep urine. The behavioural implications in host‐seeking and feeding habits are discussed.     

2-[3-(2-Thioxopyrrolidin-3-ylidene)methyl]-tryptophan,a Novel Yellow Pigment in Salted Radish Roots

The structure of the yellow pigment found in salted radish roots was studied. It was found that 1-(2-thioxopyrrolidin-3-yl)-1,2,3,4-tetrahydro-β-carboline-3- carboxylic acid (TPCC) was unstable under neutral pH, and was easily converted into the yellow pigment. The yellow pigment was isolated and identified as 2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan (TPMT) by IR, MS, ¹H-, and ¹³C-NMR spectroscopy. In addition, we proved that this compound was the main yellow pigment in salted radish roots. This compound induced no mutagenicity in Salmonella typhimurium TA98 and TA100, either with or without prior activation.