Recognition of Social Identity in Ants

Recognizing the identity of others, from the individual to the group level, is a hallmark of society. Ants, and other social insects, have evolved advanced societies characterized by efficient social recognition systems. Colony identity is mediated by colony specific signature mixtures, a blend of hydrocarbons present on the cuticle of every individual (the “label”). Recognition occurs when an ant encounters another individual, and compares the label it perceives to an internal representation of its own colony odor (the “template”). A mismatch between label and template leads to rejection of the encountered individual. Although advances have been made in our understanding of how the label is produced and acquired, contradictory evidence exists about information processing of recognition cues. Here, we review the literature on template acquisition in ants and address how and when the template is formed, where in the nervous system it is localized, and the possible role of learning. We combine seemingly contradictory evidence in to a novel, parsimonious theory for the information processing of nestmate recognition cues

Dinomyrmex gigas (Latreille, 1802): a potential icon for Taman Negara Johor Endau Rompin

Dinomyrmex gigas (Latreille, 1802) is one of the largest ants in the world and the largest in Southeast Asia. It is also more commonly known as the giant forest ant. This large charismatic ant can be found in the forests of Southeast Asia, however it is not often sighted by the public due to its predominant nocturnal nature. Despite being considerably well studied compared to its smaller counterparts, most people know little about the giant forest ant beyond its large size. Most studies on this species focus on the populations found in Malaysia and Brunei characterizing many aspects of the natural history and biology of this species including its foraging behaviour, diet, territoriality, reproduction and colony structure. While much is known about the biology of this species, fragmented forest habitats may have an impact on the viability and behaviour of this majestic giant ant of the forest. This study involved insects’ viability observation and sampling of ant specimens. The results of observations showed that D. gigas is viable in Endau Rompin Johor National Park (TNJER). Then, various ecological aspects of D. gigas was investigated through field studies and secondary information. Due to its size and uniqueness this species has a potential to be developed into a nature tourism product for Malaysia. The present study elaborated to further discover its daily activity, nesting and defence behaviour which could be useful in developing it into a nature tourism product. As the species is also limited in distribution to undisturbed forest, the issue of its survival is discussed with relation to conservation of the tropical rainforest

Type I/II interferon in HIV-1-infected patients: expression in gut mucosa and in peripheral blood mononuclear cells and its modification upon probiotic supplementation

Expression of type I and II interferon (IFN) was evaluated in gut-associated lymphoid tissue (GALT) and peripheral blood mononuclear cells (PBMCs) of HIV-1-positive patients on long-term, suppressive, antiretroviral therapy before and after probiotic supplementation. IFNα subtypes and IFNβ were expressed at higher levels in GALT compared to PBMC, whereas an opposite trend of expression was recorded for IFNγ. An increase of IFNα6, IFNα10, IFNα14, IFNα17, and IFNα21 and a decrease of IFNγ were observed in both anatomical sites after probiotic supplementation

Crozier’s paradox revisited: maintenance of genetic recognition systems by disassortative mating

BackgroundOrganisms are predicted to behave more favourably towards relatives, and kin-biased cooperation has been found in all domains of life from bacteria to vertebrates. Cooperation based on genetic recognition cues is paradoxical because it disproportionately benefits individuals with common phenotypes, which should erode the required cue polymorphism. Theoretical models suggest that many recognition loci likely have some secondary function that is subject to diversifying selection, keeping them variable.ResultsHere, we use individual-based simulations to investigate the hypothesis that the dual use of recognition cues to facilitate social behaviour and disassortative mating (e.g. for inbreeding avoidance) can maintain cue diversity over evolutionary time. Our model shows that when organisms mate disassortatively with respect to their recognition cues, cooperation and recognition locus diversity can persist at high values, especially when outcrossed matings produce more surviving offspring. Mating system affects cue diversity via at least four distinct mechanisms, and its effects interact with other parameters such as population structure. Also, the attrition of cue diversity is less rapid when cooperation does not require an exact cue match. Using a literature review, we show that there is abundant empirical evidence that heritable recognition cues are simultaneously used in social and sexual behaviour.ConclusionsOur models show that mate choice is one possible resolution of the paradox of genetic kin recognition, and the literature review suggests that genetic recognition cues simultaneously inform assortative cooperation and disassortative mating in a large range of taxa. However, direct evidence is scant and there is substantial scope for future work

Unexpected increase of myocardial extracellular volume fraction in low cardiovascular risk HIV patients

Background People living with HIV (PLWH) are prone to develop sub-clinical Cardiovascular (CV) disease, despite the effectiveness of combined Antiretroviral Therapy (cART). Algorithms developed to predict CV risk in the general population could be inaccurate when applied to PLWH. Myocardial Extra-Cellular Matrix (ECM) expansion, measured by computed tomography, has been associated with an increased CV vulnerability in HIV-negative population. Measurement of Myocardial Extra-Cellular Volume (ECV) by computed tomography or magnetic resonance, is considered a useful surrogate for clinical evaluation of ECM expansion. In the present study, we aimed to determine the extent of cardiovascular involvement in asymptomatic HIV-infected patients with the use of a comprehensive cardiac computed tomography (CCT) approach. Materials and methods In the present study, ECV in low atherosclerotic CV risk PLWH was compared with ECV of age and gender matched HIV- individuals. 53 asymptomatic HIV + individuals (45 males, age 48 (42.5–48) years) on effective cART (CD4 + cell count: 450 cells/µL (IQR: 328–750); plasma HIV RNA: <37 copies/ml in all subjects) and 18 age and gender matched controls (14 males, age 55 (44.5–56) years) were retrospectively enrolled. All participants underwent CCT protocol to obtain native and postcontrast Hounsfield unit values of blood and myocardium, ECM was calculated accordingly. Results The ECV was significantly higher in HIV + patients than in the control group (ECV: 31% (IQR: 28%-31%) vs. 27.4% (IQR: 25%-28%), p < 0.001). The duration of cART (standardized β = 0.56 (0.33–0.95), p = 0.014) and the years of exposure to HIV infection (standardized β = 0.53 (0.4–0.92), p < 0.001), were positively and strongly associated with ECV values. Differences in ECV (p < 0.001) were also observed regarding the duration of cART exposure (< 5 years, 5–10 years and > 10 years). Moreover, ECV was independently associated with age of participants (standardized β = 0.42 (0.33–0.89), p = 0.084). Conclusions HIV infection and exposure to antiretrovirals play a detrimental role on ECV expansion. An increase in ECV indicates ECM expansion, which has been associated to a higher CV risk in the general population. The non-invasive evaluation of ECM trough ECV could represent an important tool to further understand the relationship between HIV infection, cardiac pathophysiology and the increased CV risk observed in PLWH

LOW DROSS GENERATION WITH OXY-FUEL SYSTEM

Yield increase in aluminum melting operation is the most challenging goal to achieve. It has been proven that conventional oxy-fuel system can promote significant productivity increase and reduction in specific energy consumption. However, dross formation has been always a concern not only with oxy-fuel burner but also with airfuel burners. Praxair developed two new generation oxy-fuel burners for the aluminum industry, the Circular Motion Flame Burner and the Variable Oxidant Burner. The burners developed each one for specific furnace method of operation achieved reduction in dross formation by more than 25%, reduction in specific fuel consumption by up to 50%, 30% higher specific melt rate compared to traditional oxy-fuel process, increase in specific melt rate by a factor of two, and quality improvement. The Circular Motion Flame Burner, suitable for short heat cycles and continuous furnaces, promotes a nonstationary flame and very uniform heat transfer pattern to the process. The Variable Oxidant Burner suitable for short melting cycles and long holding cycles can be operated at the minimized fuel consumption by varying the oxygen concentration in the oxidant according to the phase throughout the heat cycle. Both burners designed for deep staging promote low peak flame temperature and consequently ultra low NOx emission rate

Measurement of the cosmic ray hadron spectrum up to 30 TeV at mountain altitude: the primary proton spectrum

The flux of cosmic ray hadrons at the atmospheric depth of 820 g/cm^2 has been measured by means of the EAS-TOP hadron calorimeter (Campo Imperatore, National Gran Sasso Laboratories, 2005 m a.s.l.). The hadron spectrum is well described by a single power law : S(E_h) = (2.25 +- 0.21 +- 0.34(sys)) 10^(-7)(E_h/1000)^(-2.79 +- 0.05) m^(-2) s^(-1) sr^(-1) GeV^(-1) over the energy range 30 GeV-30 TeV. The procedure and the accuracy of the measurement are discussed. The primary proton spectrum is derived from the data by using the CORSIKA/QGSJET code to compute the local hadron flux as a function of the primary proton spectrum and to calculate and subtract the heavy nuclei contribution (basing on direct measurements). Over a wide energy range E_0 = 0.5-50 TeV its best fit is given by a single power law : S(E_0) = (9.8 +- 1.1 +- 1.6(sys)) 10^(-5) (E_0/1000)^(-2.80 +- 0.06) m^(-2) s^(-1) sr^(-1) GeV^(-1). The validity of the CORSIKA/QGSJET code for such application has been checked using the EAS-TOP and KASCADE experimental data by reproducing the ratio of the measured hadron fluxes at the two experimental depths (820 and 1030 g/cm^2 respectively) at better than 10% in the considered energy range.Comment: 16 pages, 9 figures, accepted for publication in Astroparticle Physic

New Translational Trends in Personalized Medicine: Autologous Peripheral Blood Stem Cells and Plasma for COVID-19 Patient

The COVID-19 pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), still remains a severe threat. At the time of writing this paper, the second infectious wave has caused more than 280,000 deaths all over the world. Italy was one of the first countries involved, with more than 200,000 people reported as infected and 30,000 deaths. There are no specific treatments for COVID-19 and the vaccine still remains somehow inconclusive. The world health community is trying to define and share therapeutic protocols in early and advanced clinical stages. However, numbers remain critical with a serious disease rate of 14%, ending with sepsis, acute respiratory distress syndrome (ARDS), multiple organ failure (MOF) and vascular and thromboembolic findings. The mortality rate was estimated within 2–3%, and more than double that for individuals over 65 years old; almost one patient in three dies in the Intensive Care Unit (ICU). Efforts for effective solutions are underway with multiple lines of investigations, and health authorities have reported success treating infected patients with donated plasma from survivors of the illness, the proposed benefit being protective antibodies formed by the survivors. Plasma transfusion, blood and stemcells, either autologous or allograft transplantation, are not novel therapies, and in this short paper,we propose therapeutic autologous plasma and peripheral blood stem cells as a possible treatmentfor fulminant COVID-19 infection