Flavor conversion of cosmic neutrinos from hidden jets

High energy cosmic neutrino fluxes can be produced inside relativistic jets under the envelopes of collapsing stars. In the energy range E ~ (0.3 - 1e5) GeV, flavor conversion of these neutrinos is modified by various matter effects inside the star and the Earth. We present a comprehensive (both analytic and numerical) description of the flavor conversion of these neutrinos which includes: (i) oscillations inside jets, (ii) flavor-to-mass state transitions in an envelope, (iii) loss of coherence on the way to observer, and (iv) oscillations of the mass states inside the Earth. We show that conversion has several new features which are not realized in other objects, in particular interference effects ("L- and H- wiggles") induced by the adiabaticity violation. The neutrino-neutrino scattering inside jet and inelastic neutrino interactions in the envelope may produce some additional features at E > 1e4 GeV. We study dependence of the probabilities and flavor ratios in the matter-affected region on angles theta13 and theta23, on the CP-phase delta, as well as on the initial flavor content and density profile of the star. We show that measurements of the energy dependence of the flavor ratios will, in principle, allow to determine independently the neutrino and astrophysical parameters.Comment: 56 pages, 19 figures. Minor changes. Accepted by JHEP

Midgut microbiota of the malaria mosquito vector Anopheles gambiae and Interactions with plasmodium falciparum Infection

The susceptibility of Anopheles mosquitoes to Plasmodium infections relies on complex interactions between the insect vector and the malaria parasite. A number of studies have shown that the mosquito innate immune responses play an important role in controlling the malaria infection and that the strength of parasite clearance is under genetic control, but little is known about the influence of environmental factors on the transmission success. We present here evidence that the composition of the vector gut microbiota is one of the major components that determine the outcome of mosquito infections. A. gambiae mosquitoes collected in natural breeding sites from Cameroon were experimentally challenged with a wild P. falciparum isolate, and their gut bacterial content was submitted for pyrosequencing analysis. The meta-taxogenomic approach revealed a broader richness of the midgut bacterial flora than previously described. Unexpectedly, the majority of bacterial species were found in only a small proportion of mosquitoes, and only 20 genera were shared by 80% of individuals. We show that observed differences in gut bacterial flora of adult mosquitoes is a result of breeding in distinct sites, suggesting that the native aquatic source where larvae were grown determines the composition of the midgut microbiota. Importantly, the abundance of Enterobacteriaceae in the mosquito midgut correlates significantly with the Plasmodium infection status. This striking relationship highlights the role of natural gut environment in parasite transmission. Deciphering microbe-pathogen interactions offers new perspectives to control disease transmission.Institut de Recherche pour le Developpement (IRD); French Agence Nationale pour la Recherche [ANR-11-BSV7-009-01]; European Community [242095, 223601]info:eu-repo/semantics/publishedVersio

Bacterial associations reveal spatial population dynamics in Anopheles gambiae mosquitoes

The intolerable burden of malaria has for too long plagued humanity and the prospect of eradicating malaria is an optimistic, but reachable, target in the 21st century. However, extensive knowledge is needed about the spatial structure of mosquito populations in order to develop effective interventions against malaria transmission. We hypothesized that the microbiota associated with a mosquito reflects acquisition of bacteria in different environments. By analyzing the whole-body bacterial flora of An. gambiae mosquitoes from Burkina Faso by 16 S amplicon sequencing, we found that the different environments gave each mosquito a specific bacterial profile. In addition, the bacterial profiles provided precise and predicting information on the spatial dynamics of the mosquito population as a whole and showed that the mosquitoes formed clear local populations within a meta-population network. We believe that using microbiotas as proxies for population structures will greatly aid improving the performance of vector interventions around the world

Peripersonal space representation develops independently from visual experience

Our daily-life actions are typically driven by vision. When acting upon an object, we need to represent its visual features (e.g. shape, orientation, etc.) and to map them into our own peripersonal space. But what happens with people who have never had any visual experience? How can they map object features into their own peripersonal space? Do they do it differently from sighted agents? To tackle these questions, we carried out a series of behavioral experiments in sighted and congenitally blind subjects. We took advantage of a spatial alignment effect paradigm, which typically refers to a decrease of reaction times when subjects perform an action (e.g., a reach-To-grasp pantomime) congruent with that afforded by a presented object. To systematically examine peripersonal space mapping, we presented visual or auditory affording objects both within and outside subjects' reach. The results showed that sighted and congenitally blind subjects did not differ in mapping objects into their own peripersonal space. Strikingly, this mapping occurred also when objects were presented outside subjects' reach, but within the peripersonal space of another agent. This suggests that (the lack of) visual experience does not significantly affect the development of both one's own and others' peripersonal space representation

Communication Impairments in Mice Lacking Shank1: Reduced Levels of Ultrasonic Vocalizations and Scent Marking Behavior

Autism is a neurodevelopmental disorder with a strong genetic component. Core symptoms are abnormal reciprocal social interactions, qualitative impairments in communication, and repetitive and stereotyped patterns of behavior with restricted interests. Candidate genes for autism include the SHANK gene family, as mutations in SHANK2 and SHANK3 have been detected in several autistic individuals. SHANK genes code for a family of scaffolding proteins located in the postsynaptic density of excitatory synapses. To test the hypothesis that a mutation in SHANK1 contributes to the symptoms of autism, we evaluated Shank1−/− null mutant mice for behavioral phenotypes with relevance to autism, focusing on social communication. Ultrasonic vocalizations and the deposition of scent marks appear to be two major modes of mouse communication. Our findings revealed evidence for low levels of ultrasonic vocalizations and scent marks in Shank1−/− mice as compared to wildtype Shank1+/+ littermate controls. Shank1−/− pups emitted fewer vocalizations than Shank1+/+ pups when isolated from mother and littermates. In adulthood, genotype affected scent marking behavior in the presence of female urinary pheromones. Adult Shank1−/− males deposited fewer scent marks in proximity to female urine than Shank1+/+ males. Call emission in response to female urinary pheromones also differed between genotypes. Shank1+/+ mice changed their calling pattern dependent on previous female interactions, while Shank1−/− mice were unaffected, indicating a failure of Shank1−/− males to learn from a social experience. The reduced levels of ultrasonic vocalizations and scent marking behavior in Shank1−/− mice are consistent with a phenotype relevant to social communication deficits in autism.National Institute of Mental Health (U.S.) (Intramural Research Program)Simons Foundatio

Born to be green: new insights into the economics and management of green entrepreneurship

While the number of green start-ups has steadily increased around the world in response to the environmental problems demanding immediate solutions, there are several unresolved questions on the behaviour and performance of such ventures. The papers in this special issue shed light on these issues by underscoring the role of several factors, such as industry life cycles, knowledge spillovers, institutions, and availability of external finance, in shaping decision-making and firm behaviour in green start-ups. This paper highlights the state-of-the art developments in the literature, discusses the key contributions of the papers put together in this special issue and presents a future research agenda for scholars interested in green entrepreneurship

New physical characterization of the Fontana Lapilli basaltic Plinian eruption, Nicaragua

The Fontana Lapilli deposit was erupted in the late Pleistocene from a vent, or multiple vents, located near Masaya volcano (Nicaragua) and is the product of one of the largest basaltic Plinian eruptions studied so far. This eruption evolved from an initial sequence of fluctuating fountain-like events and moderately explosive pulses to a sustained Plinian episode depositing fall beds of highly vesicular basaltic-andesite scoria (SiO2 > 53 wt%). Samples show unimodal grain size distribution and a moderate sorting that are uniform in time. The juvenile component predominates (> 96 wt%) and consists of vesicular clasts with both sub-angular and fluidal, elongated shapes. We obtain a maximum plume height of 32 km and an associated mass eruption rate of 1.4 × 108 kg s−1 for the Plinian phase. Estimates of erupted volume are strongly sensitive to the technique used for the calculation and to the distribution of field data. Our best estimate for the erupted volume of the majority of the climactic Plinian phase is between 2.9 and 3.8 km3 and was obtained by applying a power-law fitting technique with different integration limits. The estimated eruption duration varies between 4 and 6 h. Marine-core data confirm that the tephra thinning is better fitted by a power-law than by an exponential trend

The effects of visual control and distance in modulating peripersonal spatial representation

In the presence of vision, finalized motor acts can trigger spatial remapping, i.e., reference frames transformations to allow for a better interaction with targets. However, it is yet unclear how the peripersonal space is encoded and remapped depending on the availability of visual feedback and on the target position within the individual’s reachable space, and which cerebral areas subserve such processes. Here, functional magnetic resonance imaging (fMRI) was used to examine neural activity while healthy young participants performed reach-to-grasp movements with and without visual feedback and at different distances of the target from the effector (near to the hand–about 15 cm from the starting position–vs. far from the hand–about 30 cm from the starting position). Brain response in the superior parietal lobule bilaterally, in the right dorsal premotor cortex, and in the anterior part of the right inferior parietal lobule was significantly greater during visually-guided grasping of targets located at the far distance compared to grasping of targets located near to the hand. In the absence of visual feedback, the inferior parietal lobule exhibited a greater activity during grasping of targets at the near compared to the far distance. Results suggest that in the presence of visual feedback, a visuo-motor circuit integrates visuo-motor information when targets are located farther away. Conversely in the absence of visual feedback, encoding of space may demand multisensory remapping processes, even in the case of more proximal targets