204 research outputs found
The Influence of Host Fruit and Temperature on the Body Size of Adult Ceratitis capitata (Diptera: Tephritidae) under Laboratory and Field conditions
The adult body size of the Mediterranean fruit Ăy, Ceratitis capitata (Wiedemann)
(Diptera: Tephritidae), varies in natural conditions. Body size is an important Ătness indicator in the
Mediterranean fruit Ăy;largerindividuals are more competitive at mating and have a greater dispersion
capacity and fertility. Both temperature during larval development and host fruit quality have been
cited as possible causes for this variation.We studied the inĂuence of host fruit and temperature during
larval development on adult body size (wing area) in the laboratory, and determined body size
variation in Ăeld populations of the Mediterannean fruit Ăy in eastern Spain. Field Ăies measured had
two origins: 1) Ăies periodically collected throughout the year in Ăeld traps from 32 citrus groves,
during the period 2003Ă2007; and 2) Ăies evolved from different fruit species collected between June
and December in 2003 and 2004. In the lab, wing area of male and female adults varied signiĂcantly
with temperature during larval development, being larger at the lowest temperature. Adult size also
was signiĂcantly different depending on the host fruit in which larvae developed. The size of the Ăies
captured at the Ăeld, either from traps or from fruits, varied seasonally showing a gradual pattern of
change along the year. The largest individuals were obtained during winter and early spring and the
smallest during late summer. In Ăeld conditions, the size of the adult Mediterannean fruit Ăy seems
apparently more related with air temperature than with host fruit. The implications of this adult size
pattern on the biology ofC. capitata and on the application of the sterile insect technique are discussed.We thank Apostolos Pekas for his useful comments on previous versions of the manuscript. This work was supported by the project RTA03-103-C6-3 assigned to F. G. M. from the Ministerio de Educacion y Ciencia of Spain.Navarro Campos, C.; MartĂnez Ferrer, MT.; Campos, J.; Fibla, JM.; Alcaide, J.; Bargues Desolmes, L.; Marzal Moreno, C.... (2011). The Influence of Host Fruit and Temperature on the Body Size of Adult Ceratitis capitata (Diptera: Tephritidae) under Laboratory and Field conditions. Environmental Entomology. 90(4):931-938. https://doi.org/10.1603/EN10302S931938904Albajes R. Santiago-Alvarez C. 1980. Influencia de la temperatura en el desarrollo de Ceratitis capitata (Diptera: Trypetidae). An. INIA. 13: 183â190.Angilletta, Jr.,, M. J., & Dunham, A. E. (2003). The TemperatureâSize Rule in Ectotherms: Simple Evolutionary Explanations May Not Be General. 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(1991). Effect of temperature andChlorelladensity on growth and metamorphosis ofChironomus circumdatus(Kieffer) (Diptera). Aquatic Insects, 13(3), 167-177. doi:10.1080/01650429109361438Santaballa E. Laborda R. Bargues L. 2001. Tratamientos de cuarentena: evoluciĂłn y supervivencia de la mosca de las frutas Ceratitis capitata (Wiedemann) sobre cĂtricos. Levante Agric. 358: 405â412.Sharp, J. L., Boller, E. F., & Chambers, D. L. (1983). Selection for Flight Propensity of Laboratory and Wild Strains of Anastrepha suspensa and Ceratitis capitata (Diptera: Tephritidae)1. Journal of Economic Entomology, 76(2), 302-305. doi:10.1093/jee/76.2.302Sigurjonsdottir H. 1984. Food competition among Scatophaga stercoraria larvae with emphasis on its effects on reproductive success. Ecol. Entomol. 9: 81â90.Sivinski J. Aluja M. Dodson G.N. Freidberg A. Headrick D.H. Kaneshiro K.Y. Landolt P. 2000. Topics in the evolution of sexual behavior in the Tephritidae, pp. 751â792 In . Aluja M. Norrbom A. Fruit Flies (Tephritidae): Phylogeny and Evolution of Behavior. CRC, Boca Raton, FL.Stamp, N. E. (1990). Growth versus molting time of caterpillars as a function of temperature, nutrient concentration and the phenolic rutin. Oecologia, 82(1), 107-113. doi:10.1007/bf00318541Statgraphics. 1994. Version 5.1 Plus. Statistical graphics system by Statistical Graphics Corporation, Manugistics, Rockville, MD.Torres-Vila L.M. Sanchez Ă. Ponce F. Delgado E. Aza M.C. Barrena F. Ferrero J.J. Cruces E. Rodriguez F. 2006. DinĂĄmica poblacional de Bractocera oleae Gmelin en Extremadura: fluctuaciĂłn estacional en el estado reproductivo y en el tamaño inaginal. Bol. Sanid. Veg., Plagas. 32: 57â69.Whittier, T. S., Nam, F. Y., Shelly, T. E., & Kaneshiro, K. Y. (1994). Male courtship success and female discrimination in the mediterranean fruit fly (Diptera: Tephritidae). Journal of Insect Behavior, 7(2), 159-170. doi:10.1007/bf01990078Yuval, B., Wekesa, J. W., Lemenager, D., Kauffman, E. E., & Washino, R. K. (1993). Seasonal Variation in Body Size of Mosquitoes (Diptera: Culicidae) in a Rice Culture Agroecosystem. Environmental Entomology, 22(2), 459-463. doi:10.1093/ee/22.2.459Zucoloto F.S. 1987. Feeding habits of Ceratitis capitata (Diptera: Tephritidae): can larvae recognize a nutritionally effective diet?. J. Insect Physiol. 33: 349â353
Influence of ecological infrastructures on the increase of biodiversity and conservation of beneficial arthropods in citrus orchards
[EN] We performed a study in nineteen citrus plots representative of the agricultural landscape of
the municipality of Altea (100 km south of Valencia, in eastern Spain) in order to determine the
influence of ecological infrastructures on biodiversity and conservation of beneficial arthropods. The
landscape was dominated by small citrus orchards mixed with low density urban areas, a consequence
of touristic urban pressure. We have considered five factors: pest management system (zero residues
vs. conventional), size of the plot, distance to nearest natural habitat, presence/absence of cover crop,
and presence/absence of other non-citrus fruits in the plot. Four of the five factors showed a positive
influence on biodiversification and conservation of beneficials: small plot size, short distance to
natural habitat, presence of vegetation cover and presence of other fruits. These are the factors to
promote in order to develop biological strategies alternative to traditional pesticide use in the
management of citrus pests. Only the factor âpest management systemâ does not show a significant
influence on biodiversity or on abundance of biological control agents.Laborda Cenjor, R.; Bertomeu Cucart, S.; Sanchez Domingo, A.; Xamani Monserrat, P.; Tarazona Campos, S.; Ibañez, J.; GarcĂa Prats, A.... (2013). Influence of ecological infrastructures on the increase of biodiversity and conservation of beneficial arthropods in citrus orchards. En Integrated Control in Citrus Fruit Crops. International Organization for Biological and Integrated Control of Noxious Animals and Plants, West Palearctic Regional Section (IOBC-WPRS). 111-115. http://hdl.handle.net/10251/54941S11111
Discovery of biomarkers for glycaemic deterioration before and after the onset of type 2 diabetes: rationale and design of the epidemiological studies within the IMI DIRECT Consortium
Aims/hypothesis The DIRECT (Diabetes Research on Patient Stratification) Study is part of a European Union Framework 7 Innovative Medicines Initiative project, a joint undertaking between four industry and 21 academic partners throughout Europe. The Consortium aims to discover and validate biomarkers that: (1) predict the rate of glycaemic deterioration before and after type 2 diabetes onset; (2) predict the response to diabetes therapies; and (3) help stratify type 2 diabetes into clearly definable disease subclasses that can be treated more effectively than without stratification. This paper describes two new prospective cohort studies conducted as part of DIRECT. Methods Prediabetic participants (target sample size 2,200-2,700) and patients with newly diagnosed type 2 diabetes (target sample size similar to 1,000) are undergoing detailed metabolic phenotyping at baseline and 18 months and 36 months later. Abdominal, pancreatic and liver fat is assessed using MRI. Insulin secretion and action are assessed using frequently sampled OGTTs in non-diabetic participants, and frequently sampled mixed-meal tolerance tests in patients with type 2 diabetes. Biosamples include venous blood, faeces, urine and nail clippings, which, among other biochemical analyses, will be characterised at genetic, transcriptomic, metabolomic, proteomic and metagenomic levels. Lifestyle is assessed using high-resolution triaxial accelerometry, 24 h diet record, and food habit questionnaires. Conclusinos/interpretation DIRECT will yield an unprecedented array of biomaterials and data. This resource, available through managed access to scientists within and outside the Consortium, will facilitate the development of new treatments and therapeutic strategies for the prevention and management of type 2 diabetes
Dietary metabolite profiling brings new insight into the relationship between nutrition and metabolic risk: An IMI Direct study
Background: Dietary advice remains the cornerstone of prevention and management of type 2 diabetes (T2D). However, understanding the efficacy of dietary interventions is confounded by the challenges inherent in assessing free living diet. Here we profiled dietary metabolites to investigate glycaemic deterioration and cardiometabolic risk in people at risk of or living with T2D.
Methods: We analysed data from plasma collected at baseline and 18-month follow-up in individuals from the Innovative Medicines Initiative (IMI) Diabetes Research on Patient Stratification (DIRECT) cohort 1 n=403 individuals with normal or impaired glucose regulation (prediabetic) and cohort 2 n=458 individuals with new onset of T2D. A dietary metabolite profile model (Tpred) was constructed using multivariate regression of 113 plasma metabolites obtained from targeted metabolomics assays. The continuous Tpred score was used to explore the relationships between diet, glycaemic deterioration and cardio-metabolic risk via multiple linear regression models.
Findings: A higher Tpred was associated with healthier diets high in wholegrain (ÎČ=0.004 g, p=0.02 and ÎČ=0.003 g, p=0.03) and lower energy intake (ÎČ=-0.0002 kcal, p=0.04 and ÎČ=-0.0002 kcal, p=0.003), and saturated fat (ÎČ=-0.03 g, p<.0001 and ÎČ=-0.03 g, p<.0001), respectively for cohort 1 and 2. In both cohorts a higher Tpred score was also associated with lower total body adiposity and improved lipid profiles HDL-cholesterol (ÎČ=0.07 mmol/L, p<.0001), (ÎČ=0.08 mmol/L, p=0.0002), and triglycerides (ÎČ=-0.1 mmol/L, p=0.003), (ÎČ=-0.2 mmol/L, p=0.0002), respectively for cohort 1 and 2. In cohort 2, the Tpred score was negatively associated with liver fat content (ÎČ=-0.74 %, p<.0001), and lower fasting concentrations of HbA1c (ÎČ=-0.9mmol/mol, p=0.02), glucose (ÎČ=-0.2 mmol/L, p=0.01) and insulin (ÎČ=-11.0 pmol/mol, p=0.01). Longitudinal analysis showed at 18-month follow up a higher Tpred score was also associated lower total body adiposity in both cohorts and lower fasting glucose (ÎČ=-0.2 mmol/L, p=0.03) and insulin (ÎČ=-9.2 pmol/mol, p=0.04) concentrations in cohort 2.
Interpretation: Plasma dietary metabolite profiling provides objective measures of diet intake, showing a relationship to glycaemic deterioration and cardiometabolic health
Observation of hard scattering in photoproduction events with a large rapidity gap at HERA
Events with a large rapidity gap and total transverse energy greater than 5
GeV have been observed in quasi-real photoproduction at HERA with the ZEUS
detector. The distribution of these events as a function of the
centre of mass energy is consistent with diffractive scattering. For total
transverse energies above 12 GeV, the hadronic final states show predominantly
a two-jet structure with each jet having a transverse energy greater than 4
GeV. For the two-jet events, little energy flow is found outside the jets. This
observation is consistent with the hard scattering of a quasi-real photon with
a colourless object in the proton.Comment: 19 pages, latex, 4 figures appended as uuencoded fil
The large trans-Neptunian object 2002 TC302 from combined stellar occultation, photometry, and astrometry data
Context. Deriving physical properties of trans-Neptunian objects is important for the understanding of our Solar System. This requires observational efforts and the development of techniques suitable for these studies. Aims. Our aim is to characterize the large trans-Neptunian object (TNO) 2002 TC302. Methods. Stellar occultations offer unique opportunities to determine key physical properties of TNOs. On 28 January 2018, 2002 TC302 occulted a mv ~ 15.3 star with designation 593-005847 in the UCAC4 stellar catalog, corresponding to Gaia source 130957813463146112. Twelve positive occultation chords were obtained from Italy, France, Slovenia, and Switzerland. Also, four negative detections were obtained near the north and south limbs. This represents the best observed stellar occultation by a TNO other than Pluto in terms of the number of chords published thus far. From the 12 chords, an accurate elliptical fit to the instantaneous projection of the body can be obtained that is compatible with the near misses. Results. The resulting ellipse has major and minor axes of 543 ± 18 km and 460 ± 11 km, respectively, with a position angle of 3 ± 1 degrees for the minor axis. This information, combined with rotational light curves obtained with the 1.5 m telescope at Sierra Nevada Observatory and the 1.23 m telescope at Calar Alto observatory, allows us to derive possible three-dimensional shapes and density estimations for the body based on hydrostatic equilibrium assumptions. The effective diameter in equivalent area is around 84 km smaller than the radiometrically derived diameter using thermal data from Herschel and Spitzer Space Telescopes. This might indicate the existence of an unresolved satellite of up to ~300 km in diameter, which is required to account for all the thermal flux, although the occultation and thermal diameters are compatible within their error bars given the considerable uncertainty of the thermal results. The existence of a potential satellite also appears to be consistent with other ground-based data presented here. From the effective occultation diameter combined with absolute magnitude measurements we derive a geometric albedo of 0.147 ± 0.005, which would be somewhat smaller if 2002 TC302 has a satellite. The best occultation light curves do not show any signs of ring features or any signatures of a global atmosphere.Funding from Spanish projects AYA2014-56637-C2-1-P, AYA2017-89637-R, from FEDER, and Proyecto de Excelencia de la Junta de AndalucĂa 2012-FQM1776 is acknowledged. We would like to acknowledge financial support by the Spanish grant AYA-RTI2018-098657-JI00 âLEO-SBNAFâ (MCIU/AEI/FEDER, UE) and the financial support from the State Agency for Research of the Spanish MCIU through the âCenter of Excellence Severo Ochoaâ award for the Instituto de AstrofĂsica de AndalucĂa (SEV- 2017-0709). Part of the research received funding from the European Unionâs Horizon 2020 Research and Innovation Programme, under grant agreement no. 687378 and from the ERC programme under Grant Agreement no. 669416 Lucky Star. The following authors acknowledge the respective CNPq grants: FB-R 309578/2017-5; RV-M 304544/2017-5, 401903/2016-8; J.I.B.C. 308150/2016-3; MA 427700/2018-3, 310683/2017-3, 473002/2013-2. This study was financed in part by the Coordenação de Aperfeiaçoamento de Pessoal de NĂvel Superior - Brasil (CAPES) - Finance Code 001 and the National Institute of Science and Technology of the e-Universe project (INCT do e-Universo, CNPq grant 465376/2014-2). GBR acknowledges CAPES-FAPERJ/PAPDRJ grant E26/203.173/2016, MA FAPERJ grant E-26/111.488/2013 and ARGJr FAPESP grant 2018/11239-8. E.F.-V. acknowledges support from the 2017 Preeminent Postdoctoral Program (P3) at UCF. C.K., R.S., A.F-T., and G.M. have been supported by the K-125015 and GINOP-2.3.2-15-2016-00003 grants of the Hungarian National Research, Development and Innovation Office (NKFIH), Hungary. G.M. was also supported by the Hungarian National Research, Development and Innovation Office (NKFIH) grant PD-128 360. R.K. and T.P. were supported by the VEGA 2/0031/18 grant
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Opioid suppression of conditioned anticipatory brain responses to breathlessness
Opioid painkillers are a promising treatment for chronic breathlessness, but are associated with potentially fatal side effects. In the treatment of breathlessness, their mechanisms of action are unclear. A better understanding might help to identify safer alternatives. Learned associations between previously neutral stimuli (e.g. stairs) and repeated breathlessness induce an anticipatory threat response that may worsen breathlessness, contributing to the downward spiral of decline seen in clinical populations. As opioids are known to influence associative learning, we hypothesized that they may interfere with the brain processes underlying a conditioned anticipatory response to breathlessness in relevant brain areas, including the amygdala and the hippocampus.
Healthy volunteers viewed visual cues (neutral stimuli) immediately before induction of experimental breathlessness with inspiratory resistive loading. Thus, an association was formed between the cue and breathlessness. Subsequently, this paradigm was repeated in two identical neuroimaging sessions with intravenous infusions of either low-dose remifentanil (0.7ng/ml target controlled infusion) or saline (randomised).
During saline infusion, breathlessness anticipation activated the right anterior insula and the adjacent operculum. Breathlessness was associated with activity in a network including the insula, operculum, dorsolateral prefrontal cortex, anterior cingulate cortex and the primary sensory and motor cortices.
Remifentanil reduced breathlessness unpleasantness but not breathlessness intensity. Remifentanil depressed anticipatory activity in the amygdala and the hippocampus that correlated with reductions in breathlessness unpleasantness. During breathlessness, remifentanil decreased activity in the anterior insula, anterior cingulate cortex and sensory motor cortices. Remifentanil-induced reduction in breathlessness unpleasantness was associated with increased activity in the rostral anterior cingulate cortex and nucleus accumbens, components of the endogenous opioid system known to decrease the perception of aversive stimuli.
These findings suggest that in addition to effects on brainstem respiratory control, opioids palliate breathlessness through an interplay of altered associative learning mechanisms. These mechanisms provide potential targets for novel ways to develop and assess treatments for chronic breathlessness
Four groups of type 2 diabetes contribute to the etiological and clinical heterogeneity in newly diagnosed individuals: An IMI DIRECT study
The presentation and underlying pathophysiology of type 2 diabetes (T2D) is complex and heterogeneous. Recent studies attempted to stratify T2D into distinct subgroups using data-driven approaches, but their clinical utility may be limited if categorical representations of complex phenotypes are suboptimal.
We apply a soft-clustering (archetype) method to characterize newly diagnosed T2D based on 32 clinical variables. We assign quantitative clustering scores for individuals and investigate the associations with glycemic deterioration, genetic risk scores, circulating omics biomarkers, and phenotypic stability over 36 months. Four archetype profiles represent dysfunction patterns across combinations of T2D etiological processes and correlate with multiple circulating biomarkers. One archetype associated with obesity, insulin resistance, dyslipidemia, and impaired ÎČ cell glucose sensitivity corresponds with the fastest disease progression and highest demand for anti-diabetic treatment. We demonstrate that clinical heterogeneity in T2D can be mapped to heterogeneity in individual etiological processes, providing a potential route to personalized treatments
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