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Elusive enemies: consumptive and ovipositional effects on mosquitoes by predatory midge larvae are enhanced in dyed environments
Mosquito-borne disease incidences continue to proliferate and cause enormous mortality and debilitation rates. Predatory natural enemies can be effective in population management strategies targeting medically-important mosquito species. However, context-dependencies and target organism behavioural responses can impede or facilitate biological control agents. Black pond dye has been shown to be a strong mosquito oviposition attractant, and could potentially be used alongside predatory agents to create mosquito population sink effects. Here, we thus examine the predatory impact of larvae of the non-biting chaoborid midge Chaoborus flavicans towards larvae of the West Nile virus vector mosquito complex Culex pipiens in the presence and absence of black pond dye. We then examine the ovipositional responses of C. pipiens to predation risk and dye in laboratory-, semi-field- and field-based trials. Larval C. flavicans exhibited potentially population destabilising type II functional responses towards mosquito larvae irrespective of the presence of pond dye. Neither consumption rates nor functional response parameters (attack rates, handling times) were significantly influenced by the presence of dye, indicating a use of hydromechanics to detect mosquito prey by chaoborids. Wild-caught adult C. pipiens did not avoid predatory chaoborids when ovipositing, however they were significantly more attracted to oviposit in dye-treated water regardless of the presence of predators. We thus demonstrate high predatory impact towards mosquito larvae by non-biting chaoborid midges during their predaceous aquatic larval stages, and proliferations of such predators may assist or augment control efforts for mosquitoes. Our results suggest a lack of influence of predatory dipterans on oviposition selectivity by C. pipiens mosquitoes, and that pond dye may enhance the efficacy of select predatory biological control agents through the creation of population sinks, characterised by high rates of oviposition and subsequent predation
Magnesiate addition/ring-expansion strategy to access the 6-7-6 tricyclic core of hetisine-type C20-diterpenoid alkaloids
A synthetic strategy to access the fused 6–7–6 tricyclic core of hetisine-type C20-diterpenoid alkaloids is reported. This strategy employs a Diels–Alder cycloaddition to assemble a fused bicyclic anhydride intermediate, which is elaborated to a vinyl lactone-acetal bearing an aromatic ring in five steps. Aromatic iodination is followed by magnesium–halogen exchange with a trialkyl magnesiate species, which undergoes intramolecular cyclization. Subsequent oxidation provides the desired 6–7–6 tricyclic diketoaldehyde, with carbonyl groups at all three positions for eventual C–N bond formation and subsequent elaboration
Non-linear Dependence of L(B) on L(FIR) and M(H2) among Spiral Galaxies and Effects of Tidal Interaction
Through the study of a carefully selected sample of isolated spiral galaxies,
we have established that two important global physical quantities for tracing
star forming activities, L(FIR) and M(H2), have non-linear dependence on
another commonly cited global quantity L(B). Furthermore we show that simple
power law relations can effectively describe these non-linear relations for
spiral galaxies spanning four orders of magnitude in FIR and M(H2) and nearly
three orders of magnitude in L(B). While the existence of non-linear dependence
of M(H2) (assuming a constant CO-to-H2 conversion) and L(FIR) on optical
luminosity L(B) has been previously noted in the literature, an improper
normalization of simple scaling by L(B) has been commonly used in many previous
studies to claim enhanced molecular gas content and induced activities among
tidally interacting and other types of galaxies. We remove these non-linear
effects using the template relations derived from the isolated galaxy sample
and conclude that strongly interacting galaxies do not have enhanced molecular
gas content, contrary to previous claims. With these non-linear relations among
L(B), L(FIR) and M(H2) properly taken into account, we confirm again that the
FIR emission and the star formation efficiency L(FIR)/M(H2) are indeed enhanced
by tidal interactions. Virgo galaxies show the same level of M(H2) and L(FIR)
as isolated galaxies. We do not find any evidence for enhanced star forming
activity among barred galaxies.Comment: 19 pages and 5 figures, requires AAS style files, ApJ, accepte
La grafomotricidad en el proceso de aprendizaje de los ni?os de 5 a?os de la instituci?n t?cnica Sumapaz Sede Santa Clara
64 p. Recurso Electr?nico?Este proyecto atenido como objetivo principal, Establecer como el proceso de aprendizaje en los ni?os de 5 a?os, a trav?s diversas estrategias, desarrollando actividades que aporten a mejorar las destrezas de las manos, los dedos y su posici?n corporal para que tengan una buena motricidad al escribir y desarrollar las habilidades b?sicas para la iniciaci?n a la escritura, basada en el desarrollo de procesos motores b?sicos como: tipos y conservaciones de trazos, precisi?n en el uso de instrumentos y el desarrollo de habilidades grafomotoras.
El t?rmino grafomotricidad en el nivel inicial es esencialmente un acto mot?rico que tiene por finalidad educar y corregir la ejecuci?n de los movimientos b?sicos que intervienen en la escritura. Estrada, R. (2006) aporta diciendo que la grafomotricidad es una fase previa a la escritura ya que supone el entrenamiento para la realizaci?n de movimientos b?sicos que forman parte de la correcta direccionalidad y trazado de las letras.
Se puede afirmar que la grafomotricidad es una posibilidad que se plantea en este proyecto como una alternativa metodol?gica para facilitar el proceso de la escritura en los ni?os de la instituci?n educativa t?cnica sumapaz sede santa clara.
Palabras claves: grafomotricidad, iniciaci?n en la escrituraThis project is considered as main objective, to establish learning strategies in the children of 5 years of the technical educational institution sumapaz seed Santa Clara headquarters, through diverse activities, developing exercises that contribute to improve the skills of the hands, the fingers and their body position To have a good motor skills in writing and develop the basic skills for initiation to writing, based on the development of basic motor processes such as types and conservations of strokes, precision in the use of instruments and the development of graphing skills. The term grafomotricidad in the initial level is essentially a motor act that has as purpose to educate and to correct the execution of the basic movements that take part in the writing. Estrada, R. (2006) contends that grafomotricidad is a pre-writing phase since it involves training for the realization of basic movements that are part of the correct directionality and layout of the letters. It is possible to affirm that the grafomotricidad is a possibility that arises in this project as a methodological alternative to facilitate the process of writing in the children of the technical educational institution sumapaz seed Santa Clara Keywords: grafomotricidad, initiation in the writin
The night-sky at the Calar Alto Observatory II: The sky at the near infrared
We present here the characterization of the night sky-brightness at the
near-infrared, the telescope seeing, and the fraction of useful time at the
Calar Alto observatory. For this study we have collected a large dataset
comprising 7311 near-infrared images taken regularly along the last four years
for the ALHAMBRA survey (J, H and Ks-bands), together with a more reduced
dataset of additional near-infrared images taken for the current study. In
addition we collected the information derived by the meteorological station at
the observatory during the last 10 years, together with the results from the
cloud sensor for the last ~2 years. We analyze the dependency of the
near-infrared night sky-brightness with the airmass and the seasons, studying
its origins and proposing a zenithal correction. A strong correlation is found
between the night sky-brightness in the Ks-band and the air temperature, with a
gradient of ~ -0.08 mag per 1 C degree. The typical (darkest) night
sky-brightness in the J, H and Ks-band are 15.95 mag (16.95 mag), 13.99 mag
(14.98 mag) and 12.39 mag (13.55 mag), respectively. These values show that
Calar Alto is as dark in the near-infrared as most of the other astronomical
astronomical sites in the world that we could compare with. Only Mauna Kea is
clearly darker in the Ks-band. The typical telescope seeing at the 3.5m is
~1.0" when converted to the V-band, being only slightly larger than the
atmospheric seeing measured at the same time by the seeing monitor, ~0.9".
Finally we estimate the fraction of useful time based on the relative humidity,
gust wind speed and presence of clouds. This fraction, ~72%, is very similar to
the one derived in Paper I, based on the fraction of time when the extinction
monitor is working.Comment: 15 pages, 6 figures, accepted to be published in PAS
Usefulness of Ultrasound in Assessing the Impact of Bariatric Surgery on Body Composition : a Pilot Study
Bariatric surgery (BS) has a significant impact on body composition. The purpose of the study is to evaluate the usefulness of musculoskeletal ultrasound (MUS) to bioelectrical impedance (BIA) in the follow-up of patients undergoing BS in terms of body composition and quality of life (QoL). This is a prospective pilot study including 32 subjects (75% female, mean age: 49.15 ± 1.9 years) who underwent BS. Fat mass (FM), lean mass (LM), and skeletal muscle index (SMI) were calculated by BIA. MUS measured subcutaneous fat (SF) and thigh muscle thickness (TMT) of the quadriceps. QoL was assessed by the Moorehead-Ardelt questionnaire. All these measurements were performed 1 month prior to BS and at 12-month follow-up. The mean BMI decreased by 6.63 ± 1.25 kg/m 2 (p =0.001). We observed significant reductions in FM (p =0.001) and SF (p =0.007) and in LM (p =0.001) but not in SMI and TMT. We found a correlation between the FM and SF (pre-surgical, r =0.42, p =0.01; post-surgical, r =0.52, p =0.003) and between SMI and TMT (pre-surgical, r =0.35, p =0.04; post-surgical, r =0.38, p =0.03). QoL test showed significant improvement (p =0.001). In addition, a correlation between the QoL questionnaire and TMT post-surgery (r =0.91, p =0.019) was observed. However, we did not find any statistically significant correlation between QoL assessment and SMI or LM. Our results suggest that MUS can be complementary to BIA for the evaluation and the follow-up of body composition after BS. TMT of quadriceps can provide relevant information about regional sarcopenia and has a significant correlation with QoL
Low-velocity transient-field technique with radioactive ion beams: G factor of the first excited 2 + state in 72Zn
A. Illana et al. ; 11 pags. ; 10 figs. ; 3 tabs. ; PACS number(s): 23.20.En, 21.10.Ky, 21.60.Cs, 27.50.+eThe g factor of the first excited 2+ state in 72Zn has been measured using the transient-field (TF) technique in combination with Coulomb excitation in inverse kinematics. This experiment presents only the third successful application of the TF method to a short-lived radioactive beam in 10 y, highlighting the intricacies of applying this technique to present and future isotope separator on-line facilities. The significance of the experimental result, g(21+)=+0.47(14), for establishing the structure of the Zn isotopes near N=40 is discussed on the basis of shell-model and beyond-mean-field calculations, the latter accounting for the triaxial degree of freedom, configuration mixing, and particle number and angular momentum projections. © 2014 American Physical Society.This work has been supported by the Spanish Ministerio de Ciencia e Innovacion under Contracts No. FPA2009-13377- ´ C02 and No. FPA2011-29854-C04 and the Spanish Project MEC Consolider-Ingenio 2010, Project No. CDS2007-00042.Peer Reviewe
Spitzer Infrared Spectrograph Observations of Magellanic Cloud Planetary Nebulae: the nature of dust in low metallicity circumstellar ejecta
We present 5 - 40 micron spectroscopy of 41 planetary nebulae (PNe) in the
Magellanic Clouds, observed with the Infrared Spectrograph on board the Spitzer
Space Telescope. The spectra show the presence of a combination of nebular
emission lines and solid-state features from dust, superimposed on the thermal
IR continuum.
By analyzing the 25 LMC and 16 SMC PNe in our sample we found that the IR
spectra of 14 LMC and 4 SMC PNe are dominated by nebular emission lines, while
the other spectra show solid-state features. We observed that the solid-state
features are compatible with carbon-rich dust grains (SiC, polycyclic aromatic
hydrocarbons (PAHs), etc.) in most cases, except in three PNe showing
oxygen-rich dust features. The frequency of carbonaceous dust features is
generally higher in LMC than in SMC PNe.
The spectral analysis allowed the correlations of the dust characteristics
with the gas composition and morphology, and the properties of the central
stars. We found that: 1) all PNe with carbonaceous dust features have C/O>1,
none of these being bipolar or otherwise highly asymmetric; 2) all PNe with
oxygen-rich dust features have C/O<1, with probable high mass progenitors if
derived from single-star evolution (these PNe are either bipolar or highly
asymmetric); 3) the dust temperature tracks the nebular and stellar evolution;
and 4) the dust production efficiency depends on metallicity, with low
metallicity environments not favoring dust production.Comment: The Astrophysical Journal, in pres
Dielectric Spectroscopy in Biomaterials: Agrophysics
Being dependent on temperature and frequency, dielectric properties are related to various
types of food. Predicting multiple physical characteristics of agri-food products has been the main
objective of non-destructive assessment possibilities executed in many studies on horticultural
products and food materials. This review manipulates the basic fundamentals of dielectric properties
with their concepts and principles. The different factors affecting the behavior of dielectric properties
have been dissected, and applications executed on different products seeking the characterization
of a diversity of chemical and physical properties are all pointed out and referenced with their
conclusions. Throughout the review, a detailed description of the various adopted measurement
techniques and the mostly popular equipment are presented. This compiled review serves in coming
out with an updated reference for the dielectric properties of spectroscopy that are applied in the
agrophysics fiel
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