Leaf Damage and Associated Cues Induce Aggressive Ant Recruitment in a Neotropical Ant-Plant

Induced chemical responses following herbivory are common in plants. Plant responses that change the level of physical or biotic defense are less well documented and poorly understood. Many Azteca spp. ants are obligate inhabitants of Cecropia spp. trees. In such ant–plant associations the ants are thought to be analogous to chemical defenses; previous experiments have demonstrated that ant occupation of C. obtusifolia reduced herbivory and plant competition and increased growth. Experiments, conducted over two years, on the dynamics of ant defense demonstrate that leaf damage caused a fivefold increase in the number of Azteca spp. ants on damaged leaves of C. obtusifolia compared to that on disturbed but undamaged control leaves. Ant activity peaked 8–12 min after damage, and differences between damaged and control leaves remained evident for 24 h. Such rapid induction of ant recruitment is likely to be particularly effective against unpredictable and mobile herbivores. The magnitude of the induced ant response to damage was strongly correlated with the number of ants patrolling the leaves before damage occurred. Ant responses to disturbance were not influenced by the presence of damage that had been applied 24 h previously. However, ant responses to subsequent damage, 24 h after initial damage, resulted in greater recruitment than to previously undamaged leaves. Ant recruitment to several other cues associated with herbivory was also tested. Presence of pyralid caterpillars that naturally feed on C. obtusifolia induced a low level of ant recruitment, and most larvae were removed from leaves by the ants within 10 min. Exposure to plant sap collected from damaged conspecifics and a commercially available green leaf volatile (hexanal) commonly released by plants after damage, both resulted in a doubling of ant numbers relative to controls. However, the levels of recruitment in response to these stimuli were insufficient to account for the high numbers of ants and persistence of recruitment observed on experimentally damaged leaves. Experimental wounding of leaves with minimal leaf tissue removal (using pin pricks) revealed that leaf wounds per se can only partially explain the induced ant recruitment following leaf damage. The type of herbivory and size of leaf wounds may be important cues for ant recruitment. Severed C. obtusifolia leaves that were freshly damaged failed to elicit an induced ant response when held adjacent to conspecific leaves with ants. However, induction of ant recruitment on damaged plants did significantly induce a low level of ant recruitment on neighboring conspecifics, providing evidence for interplant communication. Induced ant responses in the Cecropia–Azteca system are the result of multiple physical and chemical cues associated with herbivory. Ant responses to herbivory, although not previously studied in detail, are likely to be common among myrmecophytic plants and are likely to be an important component of antiherbivore defense in such systems.Funding for this study was provided by a Graduate Fellowship from the Organization for Tropical Studies and grants from the Center for Population Biology at the University of California–Davis, the Jastro Shields Research Awards Program (U.C. Davis), the Northern California Chapter of Phi Beta Kappa, and National Science Foundation Dissertation Improvement Grant DEB?9701109

Securing Automatic Package Delivery Through Building Call Box System

A user places an order for delivery in a building that uses a telephone-based call box system installed at the common door or gate to the building. When the order is placed, the user selects an option to authorize automatic delivery of the package and grants an ecommerce application authorization to temporarily intercept phone calls from the user’s building call box system. The user computing device application communicates the authorization to the account management computing system, which stores the user’s authorization and manages the delivery process. Upon receipt of a delivery update, an application on a delivery computing device transmits a notification to the account management computing system indicating the package is ready for delivery. The account management computing system transmits an intercept notice to the user computing device signaling the application on the user computing device to intercept all calls from the selected phone number for the specified duration of time, and a single-use audio request tone to the application on the user computing device. The application on the delivery computing device displays a set of delivery instructions for the delivery person to follow to initiate the call box call, hold the delivery computing device up to the call box, and wait. The application on the user computing device intercepts the call made from the call box, resulting in a connection between the application on the user computing device and the application on the delivery computing device, using the existing call box calling system. Once connected, the user computing device transmits a notification of the intercepted call to the account management computing system. The account management computing system transmits instructions to the delivery computing device to play the single-use audio request tone. The application on the delivery computing device plays the single-use audio request tone and the application on the user computing device compares the played audio request tone to the audio request tone saved in the application cache. If the tones match, the request for entry is granted. The application on the user computing device plays a building authorization tone. The call box receives the authorization tone played by the application on the user computing device to the delivery computing device over the existing call box calling system. If the tone is valid, the call box authorizes entry into the building by unlocking the door or opening the gate

System for optimizing buffering of 360 degree video streams, by taking current viewing angle into account and buffering more distant viewing angles at separate bandwidths

360-degree video is divided into a plurality of fields of view from a playback device. For example, In the case of four fields of view, referred to as quadrants, the first quadrant is defined as the current field of view of the user, the second quadrant is to the user\u27s right, the third quadrant is directly behind the user, and the fourth is to his left. During playback and buffering, a server decides what video quality (e.g., low/medium/high) to assign to each quadrant of the video based on available bandwidth and the likelihood of a viewer rotating the device to each of the quadrants

Phylogenetic escalation and decline of plant defense strategies

As the basal resource in most food webs, plants have evolved myriad strategies to battle consumption by herbivores. Over the past 50 years, plant defense theories have been formulated to explain the remarkable variation in abundance, distribution, and diversity of secondary chemistry and other defensive traits. For example, classic theories of enemy-driven evolutionary dynamics have hypothesized that defensive traits escalate through the diversification process. Despite the fact that macroevolutionary patterns are an explicit part of defense theories, phylogenetic analyses have not been previously attempted to disentangle specific predictions concerning (i) investment in resistance traits, (ii) recovery after damage, and (iii) plant growth rate. We constructed a molecular phylogeny of 38 species of milkweed and tested four major predictions of defense theory using maximum-likelihood methods. We did not find support for the growth-rate hypothesis. Our key finding was a pattern of phyletic decline in the three most potent resistance traits (cardenolides, latex, and trichomes) and an escalation of regrowth ability. Our neontological approach complements more common paleontological approaches to discover directional trends in the evolution of life and points to the importance of natural enemies in the macroevolution of species. The finding of macroevolutionary escalating regowth ability and declining resistance provides a window into the ongoing coevolutionary dynamics between plants and herbivores and suggests a revision of classic plant defense theory. Where plants are primarily consumed by specialist herbivores, regrowth (or tolerance) may be favored over resistance traits during the diversification processThis work was supported by the National Science Foundation

Reliable Integrated Satellite Terrestrial Communications using MIMO for Mitigation of Microwave Absorption by Earths Oxygen

Microwaves are used to communicate with satellite and terrestrial communication networks. But as microwaves pass through the Earth’s atmosphere, the oxygen gas absorbs microwave. In this 5G era, when the whole world is moving towards high data-rates and reliable communications, this absorption affects the data transmission in Integrated Satellite/Terrestrial Communication (ISTC) systems, which leads to degradation of the system performance. The multiple-input-multiple-output (MIMO) technology has become a boon for modern wireless communication systems to achieve the necessities of higher data-rates and communication reliability. The paper analyses the MIMO effect on block error rate (BLER), error vector magnitude (EVM) and throughput performance of the data transmission with different MIMO configurations. The paper establishes that better data-rates as well as reliable data communication is achieved with higher order MIMO configurations. MIMO 8×1 provides 5, 20 and 42.5 times improved performance to BLER; 5.26%, 25% and 81.82% in throughput; and 10.34%, 23.07% and 28% in EVM calculations as comparable to MIMO 4×1, MIMO 2×1 and SISO 1×1, respectively at 15 dB signal-to-noise ratio (SNR). The authors also give a new concept of multi-cellular layers based mobile communication network, useful for future smart cities

Plant genotype and environment interact to shape a diverse arthropod community on evening primrose (Oenothera biennis)

Both an individual's genotype and environment govern its phenotype, and this phenotype may have extended consequences for species interactions and communities. We examined the importance of plant genotype and environmental factors operating at large (habitat) and small (microhabitat) spatial scales in affecting a multitrophic arthropod community on plants. We planted 926 plants from 14 genotypes of Oenothera biennis into five natural habitats that represent the range of environments in which this plant locally occurs. Genotypic differences among plants accounted for as much as 41% of the variation in arthropod diversity (Simpson's diversity index) and also affected arthropod evenness, richness, abundance, and biomass on individual plants. However, the effects of particular plant genotypes on the arthropod community varied across habitats (i.e., there were significant plant genotype?by?habitat interactions). Plant genotype explained more variation in the arthropod community than did environmental variation among microhabitats, but less variation than habitats, as predicted by the scale?dependent hypothesis. Herbivores and omnivores were more strongly affected by plant genetic variation than predators, consistent with the notion that phytophagous insects undergo stronger reciprocal interactions with plants than do predators. We detected heritable variation in arthropod community variables and the ability for the herbivore community to select on plant traits, suggesting that evolution in O. biennis can lead to changes in the arthropod community. Genetic variation in plant size, architecture, and reproductive phenology were the plant traits most strongly correlated with arthropod community variables. Our results demonstrate that genotype?by?environment interactions are a major determinant of arthropod community structure.Our research is funded by Sigma Xi, Mountain Equipment Co?op Environment Fund, and the Natural Sciences and Engineering Research Council of Canada

Defense mutualisms enhance plant diversification

The ability of plants to form mutualistic relationships with animal defenders has long been suspected to influence their evolutionary success, both by decreasing extinction risk and by increasing opportunity for speciation through an expanded realized niche. Nonetheless, the hypothesis that defense mutualisms consistently enhance plant diversification across lineages has not been well tested due to a lack of phenotypic and phylogenetic information. Using a global analysis, we show that the >100 vascular plant families in which species have evolved extrafloral nectaries (EFNs), sugar-secreting organs that recruit arthropod mutualists, have twofold higher diversification rates than families that lack species with EFNs. Zooming in on six distantly related plant clades, trait-dependent diversification models confirmed the tendency for lineages with EFNs to display increased rates of diversification. These results were consistent across methodological approaches. Inference using reversible-jump Markov chain Monte Carlo (MCMC) to model the placement and number of rate shifts revealed that high net diversification rates in EFN clades were driven by an increased number of positive rate shifts following EFN evolution compared with sister clades, suggesting that EFNs may be indirect facilitators of diversification. Our replicated analysis indicates that defense mutualisms put lineages on a path toward increased diversification rates within and between clades, and is concordant with the hypothesis that mutualistic interactions with animals can have an impact on deep macroevolutionary patterns and enhance plant diversity.A.A.A. was supported by Grant 1118783 of the Division of Environmental Biology of the National Science Foundation (NSF) and by the John Templeton Foundation. M.G.W. was supported by the Society for the Study of Evolution’s Rosemary Grant Award and by the NSF (Graduate Research Fellowship and Doctoral Dissertation Improvement Grant)

Consequences of toxic secondary compounds in nectar for mutualist bees and antagonist butterflies

Attraction of mutualists and defense against antagonists are critical challenges for most organisms and can be especially acute for plants with pollinating and non?pollinating flower visitors. Secondary compounds in flowers have been hypothesized to adaptively mediate attraction of mutualists and defense against antagonists, but this hypothesis has rarely been tested. The tissues of milkweeds (Asclepias spp.) contain toxic cardenolides that have long been studied as chemical defenses against herbivores. Milkweed nectar also contains cardenolides, and we have examined the impact of manipulating cardenolides in nectar on the foraging choices of two flower visitors: generalist bumble bees, Bombus impatiens, which are mutualistic pollinators, and specialist monarch butterflies, Danaus plexippus, which are herbivores as larvae and ineffective pollinators as adults. Although individual bumble bees in single foraging bouts showed no avoidance of cardenolides at the highest natural concentrations reported for milkweeds, a pattern of deterrence did arise when entire colonies were allowed to forage for several days. Monarch butterflies were not deterred by the presence of cardenolides in nectar when foraging from flowers, but laid fewer eggs on plants paired with cardenolide?laced flowers compared to controls. Thus, although deterrence of bumble bees by cardenolides may only occur after extensive foraging, a primary effect of nectar cardenolides appears to be reduction of monarch butterfly oviposition.The Templeton Foundation and National Science Foundation DEB-1513839 provided financial support

Extranodal rosai dorfman disease: a case report of single soft tissue cystic lesion

Rosai-Dorfman disease (RDD) is an uncommon benign histiocytic disorder. It is found worldwide and slightly more common among in men (1.4:1), affecting individuals are with an average age of 20.6 years. Extranodal tissue involvement is documented in 25-43% of RDD patients. Here authors are discussing a case of 16-year-old male patient with the complaint of a single swelling over left forearm since one month with no lymphadenopathy. Radiology showed anechoic collection within the muscle and superficial to it. On microscopy, smear showed diffusely distributed histiocytes with cytoplasm showing intact lymphocytes with halo surrounding it (emperipolesis), without atypia. Based on cytomorphology diagnosis of Extranodal Rosai Dorfman Disease was made