Do Termites Avoid Carcasses? Behavioral Responses Depend on the Nature of the Carcasses

BACKGROUND: Undertaking behavior is a significant adaptation to social life in enclosed nests. Workers are known to remove dead colony members from the nest. Such behavior prevents the spread of pathogens that may be detrimental to a colony. To date, little is known about the ethological aspects of how termites deal with carcasses. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we tested the responses to carcasses of four species from different subterranean termite taxa: Coptotermes formosanus Shiraki and Reticulitermes speratus (Kolbe) (lower termites) and Microcerotermes crassus Snyder and Globitermes sulphureus Haviland (higher termites). We also used different types of carcasses (freshly killed, 1-, 3-, and 7-day-old, and oven-killed carcasses) and mutilated nestmates to investigate whether the termites exhibited any behavioral responses that were specific to carcasses in certain conditions. Some behavioral responses were performed specifically on certain types of carcasses or mutilated termites. C. formosanus and R. speratus exhibited the following behaviors: (1) the frequency and time spent in antennating, grooming, and carcass removal of freshly killed, 1-day-old, and oven-killed carcasses were high, but these behaviors decreased as the carcasses aged; (2) the termites repeatedly crawled under the aging carcass piles; and (3) only newly dead termites were consumed as a food source. In contrast, M. crassus and G. sulphureus workers performed relatively few behavioral acts. Our results cast a new light on the previous notion that termites are necrophobic in nature. CONCLUSION: We conclude that the behavioral response towards carcasses depends largely on the nature of the carcasses and termite species, and the response is more complex than was previously thought. Such behavioral responses likely are associated with the threat posed to the colony by the carcasses and the feeding habits and nesting ecology of a given species

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

The ant Camponotus atriceps shows electroretinogram circadian rhythms

We studied the circadian variation of the electroretinogram (ERG) response of individual isolated ants of two castes: major workers and virgin queens of the species Campanotus atriceps subjected to different experimental light protocols. The experiments demonstrated that both castes of this species show similar ERG endogenous circadian rhythms able to entrain to 24 h LD cycles changing phase and period. This is the first work reporting circadian changes in the eye's electrophysiological response to light in ants

Multisensory convergence in the mushroom bodies of ants and bees

The mushroom bodies, central neuropils in the arthropod brain, are involved in learning and memory and in the control of complex behavior. In most bisects, the mushroom bodies receive direct olfactory input in their calyx region. In Hymenoptera, olfactory input is layered in the calyx. In ants, several layers can be discriminated that correspond to different clusters of glomeruli in the antennal lobes, perhaps corresponding to different classes of odors. Only in Hymenoptera, the mushroom body calyx also receives direct visual input from the optic lobes. In bees, six calycal layers receive input from different classes of visual interneurons, probably representing different parts of the visual field and different visual properties. Taken together, the mushroom bodies receive distinct multisensory information in many segregated input layers

antennal olfactory sensitivity in response to task-related odours of three castes of the ant atta mexicana (hymenoptera : formicidae)

The relationship between scent composition and antennal sensitivity in different castes of Atta mexicana is investigated under laboratory conditions. Extracts of dead ants are analysed by gas chromatography-mass spectrometry to identify the compounds presumably responsible for the specific undertaking behaviour. Oleic acid is identified as one compound that triggers undertaking behaviour. To determine differences in odour reception between workers of different castes (i.e. foragers, undertakers and soldiers), further antennal sensitivity to task-related odours is tested using electroantennographic techniques. Soldiers are the most specialized caste because of their low response to all odours, except odourants related to alarm pheromones. The behavioural specialization of soldiers and their reduced behavioural repertoire are discussed

Comparison of international normalized ratio audit parameters in patients enrolled in GARFIELD-AF and treated with vitamin K antagonists

Vitamin K antagonist (VKA) therapy for stroke prevention in atrial fibrillation (AF) requires monitoring of the international normalized ratio (INR). We evaluated the agreement between two INR audit parameters, frequency in range (FIR) and proportion of time in the therapeutic range (TTR), using data from a global population of patients with newly diagnosed non-valvular AF, the Global Anticoagulant Registry in the FIELD\u2013Atrial Fibrillation (GARFIELD-AF). Among 17\ua0168 patients with 1-year follow-up data available at the time of the analysis, 8445 received VKA therapy (\ub1antiplatelet therapy) at enrolment, and of these patients, 5066 with 653 INR readings and for whom both FIR and TTR could be calculated were included in the analysis. In total, 70\ua0905 INRs were analysed. At the patient level, TTR showed higher values than FIR (mean, 56\ub70% vs 49\ub78%; median, 59\ub77% vs 50\ub70%). Although patient-level FIR and TTR values were highly correlated (Pearson correlation coefficient [95% confidence interval; CI], 0\ub7860 [0\ub7852\u20130\ub7867]), estimates from individuals showed widespread disagreement and variability (Lin's concordance coefficient [95% CI], 0\ub7829 [0\ub7821\u20130\ub7837]). The difference between FIR and TTR explained 17\ub74% of the total variability of measurements. These results suggest that FIR and TTR are not equivalent and cannot be used interchangeably