299 research outputs found
Enhanced fano resonance of organic material films deposited on arrays of asymmetric split-ring resonators (A-SRRs)
Depositing very thin organic films on the surface of arrays of asymmetric split-ring resonators (A-SRRs) produces a shift in their resonance spectra that can be utilized for sensitive analyte detection. Here we show that when poly-methyl-methacrylate (PMMA) is used as an organic probe (analyte) on top of the A-SRR array, the phase and amplitude of a characteristic molecular Fano resonance associated with a carbonyl bond changes according to the spectral positions of the trapped mode resonance of the A-SRRs and their plasmonic reflection peaks. Furthermore, we localize blocks of PMMA at different locations on the A-SRR array to determine the effectiveness of detection of very small amounts of non-uniformly distributed analyte
Basic tasks of sentiment analysis
Subjectivity detection is the task of identifying objective and subjective
sentences. Objective sentences are those which do not exhibit any sentiment.
So, it is desired for a sentiment analysis engine to find and separate the
objective sentences for further analysis, e.g., polarity detection. In
subjective sentences, opinions can often be expressed on one or multiple
topics. Aspect extraction is a subtask of sentiment analysis that consists in
identifying opinion targets in opinionated text, i.e., in detecting the
specific aspects of a product or service the opinion holder is either praising
or complaining about
Defects in Chiral Columnar Phases: Tilt Grain Boundaries and Iterated Moire Maps
Biomolecules are often very long with a definite chirality. DNA, xanthan and
poly-gamma-benzyl-glutamate (PBLG) can all form columnar crystalline phases.
The chirality, however, competes with the tendency for crystalline order. For
chiral polymers, there are two sorts of chirality: the first describes the
usual cholesteric-like twist of the local director around a pitch axis, while
the second favors the rotation of the local bond-orientational order and leads
to a braiding of the polymers along an average direction. In the former case
chirality can be manifested in a tilt grain boundary phase (TGB) analogous to
the Renn-Lubensky phase of smectic-A liquid crystals. In the latter case we are
led to a new "moire" state with twisted bond order. In the moire state polymers
are simultaneously entangled, crystalline, and aligned, on average, in a common
direction. In the moire state polymers are simultaneously entangled,
crystalline, and aligned, on average, in a common direction. In this case the
polymer trajectories in the plane perpendicular to their average direction are
described by iterated moire maps of remarkable complexity, reminiscent of
dynamical systems.Comment: plain TeX, (33 pages), 17 figures, some uufiled and included, the
remaining available at ftp://ftp.sns.ias.edu/pub/kamien/ or by request to
[email protected]
Surface Scaling Analysis of a Frustrated Spring-network Model for Surfactant-templated Hydrogels
We propose and study a simplified model for the surface and bulk structures
of crosslinked polymer gels, into which voids are introduced through templating
by surfactant micelles. Such systems were recently studied by Atomic Force
Microscopy [M. Chakrapani et al., e-print cond-mat/0112255]. The gel is
represented by a frustrated, triangular network of nodes connected by springs
of random equilibrium lengths. The nodes represent crosslinkers, and the
springs correspond to polymer chains. The boundaries are fixed at the bottom,
free at the top, and periodic in the lateral direction. Voids are introduced by
deleting a proportion of the nodes and their associated springs. The model is
numerically relaxed to a representative local energy minimum, resulting in an
inhomogeneous, ``clumpy'' bulk structure. The free top surface is defined at
evenly spaced points in the lateral (x) direction by the height of the topmost
spring, measured from the bottom layer, h(x). Its scaling properties are
studied by calculating the root-mean-square surface width and the generalized
increment correlation functions C_q(x)= . The surface is
found to have a nontrivial scaling behavior on small length scales, with a
crossover to scale-independent behavior on large scales. As the vacancy
concentration approaches the site-percolation limit, both the crossover length
and the saturation value of the surface width diverge in a manner that appears
to be proportional to the bulk connectivity length. This suggests that a
percolation transition in the bulk also drives a similar divergence observed in
surfactant templated polyacrylamide gels at high surfactant concentrations.Comment: 17 pages RevTex4, 10 imbedded eps figures. Expanded discussion of
multi-affinit
The Hidden Sexuality of Alexandrium Minutum: An Example of Overlooked Sex in Dinoflagellates
Dinoflagellates are haploid eukaryotic microalgae in which rapid proliferation causes dense
blooms, with harmful health and economic effects to humans. The proliferation mode is
mainly asexual, as the sexual cycle is believed to be rare and restricted to stressful environmental
conditions. However, sexuality is key to explaining the recurrence of many dinoflagellate
blooms because in many species the fate of the planktonic zygotes (planozygotes)
is the formation of resistant cysts in the seabed (encystment). Nevertheless, recent
research has shown that individually isolated planozygotes in the lab can enter other routes
besides encystment, a behavior of which the relevance has not been explored at the population
level. In this study, using imaging flow cytometry, cell sorting, and Fluorescence In
Situ Hybridization (FISH), we followed DNA content and nuclear changes in a population of
the toxic dinoflagellate Alexandrium minutum that was induced to encystment. Our results
first show that planozygotes behave like a population with an “encystment-independent”
division cycle, which is light-controlled and follows the same Light:Dark (L:D) pattern as the
cycle governing the haploid mitosis. Resting cyst formation was the fate of just a small fraction
of the planozygotes formed and was restricted to a period of strongly limited nutrient
conditions. The diploid-haploid turnover between L:D cycles was consistent with two-step
meiosis. However, the diel and morphological division pattern of the planozygote division
also suggests mitosis, which would imply that this species is not haplontic, as previously
considered, but biphasic, because individuals could undergo mitotic divisions in both the
sexual (diploid) and the asexual (haploid) phases. We also report incomplete genome duplication
processes. Our work calls for a reconsideration of the dogma of rare sex in
dinoflagellates.VersiĂłn del edito
Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus
The rejection of citrus fruit caused by infestations of the California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), raises concerns about its management. This fact has led to the introduction of new integrated control methods in citrus orchards, including the implementation of techniques based on pheromones. Previous works described efficient mating disruption pheromone dispensers to control A. aurantii in the Mediterranean region. The main aims of the present study were to adjust the timing of dispenser applications and study the importance of controlling the early first generation of A. aurantii by testing two different application dates: before and after the first CRS male flight. The efficacy of the different mating disruption strategies was tested during 2010 in an experimental orchard and these results were confirmed during 2011 in a commercial citrus farm. Results showed that every mating disruption strategy achieved significantly lower male captures in monitoring pheromone traps compared with untreated plots, as well as mean fruit infestation reductions of about 80 %. The control of the first CRS generation is not essential for achieving a good efficacy as demonstrated in two locations with different pest pressure. The late application of MD dispensers before the second CRS male flight has proven to be effective, suggesting a new advantageous way to apply mating disruption.The authors want to thank Fernando Alfaro from Denia, Antonio Caballero, and Javier Macias from Rio Tinto Fruit S.A. (Huelva, Spain) for field support. We also thank Ecologia y Proteccion Agricola SL for the pheromone supply. This work has been funded by the Spanish Ministry of Science and Innovation (project AGL2009-10725) and Agroalimed Foundation. The translation of this paper was funded by the Universidad Politecnica de Valencia (Spain).Vacas González, S.; Alfaro Cañamás, C.; Primo Millo, J.; Navarro-Llopis, V. (2015). Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus. Journal of Pest Science. 88(2):321-329. https://doi.org/10.1007/s10340-014-0623-1S321329882Avidov Z, Balshin M, Gerson U (1970) Studies on Aphytis coheni, a parasite of the California red scale, Aonidiella aurantii in Israel. Biocontrol 15:191–207Barzakay I, Hefetz A, Sternlicht M, Peleg BA, Gokkes M, Singer G, Geffen D, Kronenberg S (1986) Further field trials on management of the California red scale, Aonidiella aurantii, by mating disruption with its sex-pheromone. Phytoparasitica 14:160–161Bedford ECG (1996) Problems which we face in bringing red scale, Aonidiella aurantii (Maskell), under biological control in citrus in South Africa. Proc Int Soc Citriculture 1:485–492Campos-Rivela JM, MartĂnez-Ferrer MT, Fibla-Queralt JM (2012) Population dynamics and seasonal trend of California red scale (Aonidiella aurantii Maskell) in citrus in Northern Spain. Span J Agric Res 10:198–208Collins PJ, Lambkin TM, Bodnaruk P (1994) Suspected resistance to methidation in Aonidiella aurantii (Maskell) (Homoptera: diaspididae) from Queensland. J Aust Entomol Soc 33:325–326Corma A, Muñoz-Pallares J, Primo-Yufera E (1999) Production of semiochemical emitters having a controlled emission speed which are based on inorganic molecular sieves. World Patent WO9944420Corma A, Muñoz-Pallares J, Primo-Yufera E (2000) Emitter of semiochemical substances supported on a sepiolite, preparation process and applications. World Patent WO0002448DeBach P (1959) New species and strains of Aphytis (Hymenoptera: Eulophidae) parasitic on the California red scale, Aonidiella aurantii (Mask.), in the Orient. Ann Entomol Soc Am 52:354–362DeBach P, Argyriou L (1967) The colonization and success in Greece of some imported Aphytis spp. (Hymenoptera: Aphelinidae) parasitic on citrus scale insects (Homoptera: Diaspididae). Biocontrol 12:325–342Desneux N, Decourtye A, Delpuech JM (2007) The sublethal effects of pesticides on beneficial arthropods. Ann Rev Entomol 52:81–106Diari Oficial de la Comunitat Valenciana (DOCV) (2008) DOCV no. 5901, 26. Resolution 27 October 2008 of ConsellerĂa de Agricultura, Pesca y AlimentaciĂłn; November 2008. http://www.docv.gva.es/datos/2008/11/26/pdf/2008_13692.pdfDomĂnguez-Ruiz J, Sanchis J, Navarro-Llopis V, Primo J (2008) A new long-life trimedlure dispenser for Mediterranean fruit fly. J Econ Entomol 101:1325–1330Eliahu M, Blumberg D, Horowitz AR, Ishaaya I (2007) Effect of pyriproxyfen on developing stages and embryogenesis of California red scale (CRS), Aonidiella aurantii. Pest Manag Sci 63:743–746Furness G, Buchanan G, George R, Richardson N (1983) A history of the biological and integrated control of red scale, Aonidiella aurantii on citrus in the lower Murray Valley of Australia. Biocontrol 28:99–212Grafton-Cardwell EE, Gu P (2003) Conserving vedalia beetle, Rodolia cardinalis (Mulsant) (Coleoptera : Coccinellidae), in citrus: a continuing challenge as new insecticides gain registration. J Econ Entomol 96:1388–1398Grafton-Cardwell EE, Reagan CA (1995) Selective use of insecticides for control of armored scale (Homoptera: Diaspididae) in San-Joaquin Valley California citrus. J Econ Entomol 88:1717–1725Grafton-Cardwell EE, Vehrs SLC (1995) Monitoring for organophosphate-resistant and carbamate-resistant armored scale (Homoptera: Diaspididae) in San-Joaquin Valley citrus. J Econ Entomol 88:495–504Grafton-Cardwell EE, Lee JE, Stewart JR, Olsen KD (2006) Role of two insect growth regulators in integrated pest management of citrus scales. J Econ Entomol 99:733–744Grout TG, Richards GI (1991a) Effect of buprofezin applications at different phenological times on California red scale (Homoptera: Diaspididae). J Econ Entomol 84:1802–1805Grout TG, Richards GI (1991b) Value of pheromone traps for predicting infestations of red scale, Aonidiella aurantii (Maskell) (Homoptera: Diaspididae), limited by natural enemy activity and insecticides used to control citrus thrips, Scirtothrips aurantii Faure (Thysanoptera: Thripidae). J Appl Entomol 111:20–27Grout TG, Du Toit WJ, Hofmeyr JH, Richards GI (1989) California red scale (Homoptera: Diaspididae) phenology on citrus in South Africa. J Econ Entomol 82:793–798Hefetz A, Kronengerg S, Peleg BA, Bar-zakay I (1988) Mating disruption of the California red scale Aonidiella aurantii (Homoptera: Diaspididae). In: Proceeding 6th International Citrus Congress, Tel Aviv (Israel), pp 1121–1127Hernández-PenadĂ©s P, RodrĂguez-Reina JM, GarcĂa-MarĂ F (2002) Umbrales de tratamiento para cĂłccidos diaspĂdidos en cĂtricos. Bol San Veg Plagas 28:469–478Hothorn T, Bretz F, Westfall P (2008) Simultaneous Inference in General Parametric Models. Biometrical J 50:346–363Ioratti C, Anfora G, Tasin M, De Cristofaro A, Witzgall P, Lucchi A (2011) Chemical ecology and management of Lobesia botrana (Lepidoptera: Tortricidae). J Econ Entomol 104:1125–1137Kehat M, Anshelevich L, Harel M, Dunkelblum E (1995) Control of the codling moth (Cydia pomonella) in apple and pear orchards in Israel by mating disruption. Phytoparasitica 23:285–296Kennett CE, Hoffmann RW (1985) Seasonal development of the California red scale (Homoptera: Diaspididae) in San Joaquin Valley citrus based on degree-day accumulation. J Econ Entomol 78:73–79Levitin E, Cohen E (1998) The involvement of acetylcholinesterase in resistance of the California red scale shape Aonidiella aurantii to organophosphorus pesticides. Entomol Exp Appl 88:115–121Lykouressis D, Perdikis D, Samartzis D, Fantinou A, Toutouzas S (2005) Management of the pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) by mating disruption in cotton fields. Crop Prot 24:177–183McLaren IW, Buchanan GA (1973) Parasitism by Aphytis chrysomphali Mercet and A. melinus Debach of Californian red scale, Aonidiella aurantii (Maskell), in relation to seasonal availability of suitable stages of the scale. Austr J Zool 21:111–117Moreno DS, Kennett CE (1985) Predictive year-end California red scale (Homoptera: Diaspididae) orange fruit infestations based on catches of males in the San-Joaquin Valley. J Econ Entomol 78:1–9Moreno DS, Luck RF (1992) Augmentative releases of Aphytis melinus (Hymenoptera: Aphelinidae) to suppress California red scale (Homoptera: Diaspididae) in southern California lemon orchards. J Econ Entomol 85:1112–1119Pekas A, Aguilar A, Tena A, GarcĂa-MarĂ F (2010) Influence of host size on parasitism by Aphytis chrysomphali and A. melinus (Hymenoptera: Aphelinidae) in Mediterranean populations of California red scale Aonidiella aurantii (Hemiptera: Diaspididae). Biol Control 55:132–140Rill S, Grafton-Cardwell EE, Morse JG (2007) Effects of pyriproxyfen on California red scale (Hemiptera: Diaspididae) development and reproduction. J Econ Entomol 100:1435–1443Rodrigo E, Troncho P, GarcĂa-MarĂ F (1996) Parasitoids (Hymenoptera: Aphelinidae) of three scale insects (Homoptera: Diaspididae) in a citrus grove in Valencia, Spain. Entomophaga 41:77–94Roelofs WL, Gieselmann MJ, CardĂ© AM, Tashiro H, Moreno DS, Henrick CA, Anderson RJ (1977) Sex-pheromone of California red scale, Aonidiella aurantii. Nature 26:698–699Rongai D, Cerato C, Lazzeri L, Palmieri S, Patalano G (2008) Vegetable oil formulation as biopesticide to control California red scale (Aonidiella aurantii Maskell). J Pest Sci 81:179–185Sorribas JJ, RodrĂguez R, Rodrigo E, GarcĂa-MarĂ F (2008) Niveles de parasitismo y especies de parasitoides del piojo rojo de california Aonidiella aurantii (Hemiptera: Diaspididae) en cĂtricos de la Comunidad Valenciana. Bol San Veg Plagas 34:201–210Sorribas J, van Baaren J, Garcia-MarĂ F (2012) Effects of climate on the introduction, distribution and biotic potential of parasitoids: applications to biological control of California red scale. Biol Control 62:103–112Staten RT, Flint HM, Weddle RC, Quintero E, Zarate RE, Finell CM, Hernandes M, Yamamoto A (1987) Pink bollworm (Lepidoptera: Gelechiidae): large-scale field trials with a high-rate gossyplure formulation. J Econ Entomol 80:1267–1271Tashiro H, Chambers DL (1967) Reproduction in the California Red Scale, Aonidiella aurantii (Homoptera: Diaspididae). I. Discovery and extraction of a female sex pheromone. Ann Entomol Soc Am 60:1166–1170Tena A, Llácer E, Urbaneja A (2013) Biological control of a non-honeydew producer mediated by a distinct hierarchy of honeydew quality. Biol Control 67:117–122University of California (1991) Integrated pest management for citrus. University of California, BerkeleyVacas S, Alfaro C, Navarro-Llopis V, Primo J (2009) The first account of the mating disruption technique for the control of California red scale Aonidiella aurantii Maskell (Homoptera: Diaspididae) using new biodegradable dispensers. Bull Entomol Res 99:415–423Vacas S, Alfaro C, Navarro-Llopis V, Primo J (2010) Mating disruption of California red scale, Aonidiella aurantii Maskell (Homoptera: Diaspididae), using biodegradable mesoporous pheromone dispensers. Pest Manag Sci 66:745–751Vacas S, Vanaclocha P, Alfaro C, Primo J, VerdĂş MJ, Urbaneja A, Navarro-Llopis V (2011) Mating disruption for the control of Aonidiella aurantii Maskell (Hemiptera: Diaspididae) may contribute to increased effectiveness of natural enemies. Pest Manag Sci 68:142–148Vanaclocha P, Vacas S, Alfaro C, Primo J, VerdĂş MJ, Navarro-Llopis V, Urbaneja A (2012) Life history parameters and scale-cover surface area of Aonidiella aurantii are altered in a mating disruption environment: implications for biological control. Pest Manag Sci 68:1092–1097Vanaclocha P, Vidal-Quist C, Oheix S, MontĂłn H, Planes L, Catalán J, Tena A, VerdĂş MJ, Urbaneja A (2013) Acute toxicity in laboratory tests of fresh and aged residues of pesticides used in citrus on the parasitoid Aphytis melinus. J Pest Sci 86:329–336Yarom I, Blumberg D, Ishaaya I (1988) Effects of buprofezin on California red scale (Homoptera: Diaspididae) and Mediterranean black scale (Homoptera: Coccidae). J Econ Entomol 81:1581–1585Yust HR, Nelson HD, Busbey RL (1943) Comparative susceptibility of two strains of California red scale to HCN, with special reference to the inheritance of resistance. J Econ Entomol 36:744–74
Imagined gait modulates neuronal network dynamics in the human pedunculopontine nucleus
The pedunculopontine nucleus (PPN) is a part of the mesencephalic locomotor region and is thought to be important for the initiation and maintenance of gait. Lesions of the PPN induce gait deficits, and the PPN has therefore emerged as a target for deep brain stimulation for the control of gait and postural disability. However, the role of the PPN in gait control is not understood. Using extracellular single-unit recordings in awake patients, we found that neurons in the PPN discharged as synchronous functional networks whose activity was phase locked to alpha oscillations. Neurons in the PPN responded to limb movement and imagined gait by dynamically changing network activity and decreasing alpha phase locking. Our results indicate that different synchronous networks are activated during initial motor planning and actual motion, and suggest that changes in gait initiation in Parkinson's disease may result from disrupted network activity in the PPN
The Emergence of Emotions
Emotion is conscious experience. It is the affective aspect of consciousness. Emotion arises from sensory stimulation and is typically accompanied by physiological and behavioral changes in the body. Hence an emotion is a complex reaction pattern consisting of three components: a physiological component, a behavioral component, and an experiential (conscious) component. The reactions making up an emotion determine what the emotion will be recognized as. Three processes are involved in generating an emotion: (1) identification of the emotional significance of a sensory stimulus, (2) production of an affective state (emotion), and (3) regulation of the affective state. Two opposing systems in the brain (the reward and punishment systems) establish an affective value or valence (stimulus-reinforcement association) for sensory stimulation. This is process (1), the first step in the generation of an emotion. Development of stimulus-reinforcement associations (affective valence) serves as the basis for emotion expression (process 2), conditioned emotion learning acquisition and expression, memory consolidation, reinforcement-expectations, decision-making, coping responses, and social behavior. The amygdala is critical for the representation of stimulus-reinforcement associations (both reward and punishment-based) for these functions. Three distinct and separate architectural and functional areas of the prefrontal cortex (dorsolateral prefrontal cortex, orbitofrontal cortex, anterior cingulate cortex) are involved in the regulation of emotion (process 3). The regulation of emotion by the prefrontal cortex consists of a positive feedback interaction between the prefrontal cortex and the inferior parietal cortex resulting in the nonlinear emergence of emotion. This positive feedback and nonlinear emergence represents a type of working memory (focal attention) by which perception is reorganized and rerepresented, becoming explicit, functional, and conscious. The explicit emotion states arising may be involved in the production of voluntary new or novel intentional (adaptive) behavior, especially social behavior
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