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1.
Public Health ; 231: 1-6, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582055

RESUMEN

OBJECTIVES: In Chile, colorectal cancer (CRC) is the fourth cause of death by cancer. Few studies have evaluated the role of contextual and individual socio-economic variables associated with premature death by CRC (<70 years). We analyzed the association between socio-economic factors (at individual and contextual levels) and premature death from CRC in Santiago de Chile. STUDY DESIGN: This was a cross-sectional study. METHODS: We analyzed deaths from CRC between 2014 and 2018 using data published by the Ministry of Health. Individual predictors were sex, marital status, and educational level. Contextual variable included the Social Priority Index (SPI) of the commune where the deceased lived. The association was assessed through multilevel logistic regression models. RESULTS: During the period, 4762 deaths occurred (51.7% women); 39.3% were premature. At the individual level, male sex (odds ratio [OR] 1.36; 95% confidence interval [CI] 1.20-1.53) and single marital status (OR 1.45; 95% CI 1.24-1.68) were associated with premature death from CRC. Primary or lower education was a protective factor (OR 0.53; 95% CI 0.47-0.60). At the contextual level, communes with a higher SPI were three times more at risk than those with a lower SPI (OR 3.13; 95% CI 2.15-4.57). CONCLUSIONS: This study showed that individual and contextual socio-economic variables are related to premature death from CRC. Residing in communes with greater socio-economic vulnerability was associated with greater risk. To reduce this gap, it is urgent to design and implement structural policies to reduce social inequities and improve access to health care.


Asunto(s)
Neoplasias Colorrectales , Mortalidad Prematura , Factores Socioeconómicos , Humanos , Neoplasias Colorrectales/mortalidad , Masculino , Femenino , Estudios Transversales , Chile/epidemiología , Persona de Mediana Edad , Anciano , Adulto , Factores de Riesgo , Factores Sexuales
2.
Phys Rev Lett ; 131(2): 021802, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37505961

RESUMEN

This Letter reports one of the most precise measurements to date of the antineutrino spectrum from a purely ^{235}U-fueled reactor, made with the final dataset from the PROSPECT-I detector at the High Flux Isotope Reactor. By extracting information from previously unused detector segments, this analysis effectively doubles the statistics of the previous PROSPECT measurement. The reconstructed energy spectrum is unfolded into antineutrino energy and compared with both the Huber-Mueller model and a spectrum from a commercial reactor burning multiple fuel isotopes. A local excess over the model is observed in the 5-7 MeV energy region. Comparison of the PROSPECT results with those from commercial reactors provides new constraints on the origin of this excess, disfavoring at 2.0 and 3.7 standard deviations the hypotheses that antineutrinos from ^{235}U are solely responsible and noncontributors to the excess observed at commercial reactors, respectively.

3.
Phys Rev Lett ; 128(8): 081801, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35275656

RESUMEN

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

4.
Phys Rev Lett ; 128(8): 081802, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35275665

RESUMEN

The PROSPECT and STEREO collaborations present a combined measurement of the pure ^{235}U antineutrino spectrum, without site specific corrections or detector-dependent effects. The spectral measurements of the two highest precision experiments at research reactors are found to be compatible with χ^{2}/ndf=24.1/21, allowing a joint unfolding of the prompt energy measurements into antineutrino energy. This ν[over ¯]_{e} energy spectrum is provided to the community, and an excess of events relative to the Huber model is found in the 5-6 MeV region. When a Gaussian bump is fitted to the excess, the data-model χ^{2} value is improved, corresponding to a 2.4σ significance.

5.
Phys Rev Lett ; 122(25): 251801, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31347897

RESUMEN

This Letter reports the first measurement of the ^{235}U ν[over ¯]_{e} energy spectrum by PROSPECT, the Precision Reactor Oscillation and Spectrum experiment, operating 7.9 m from the 85 MW_{th} highly enriched uranium (HEU) High Flux Isotope Reactor. With a surface-based, segmented detector, PROSPECT has observed 31678±304(stat) ν[over ¯]_{e}-induced inverse beta decays, the largest sample from HEU fission to date, 99% of which are attributed to ^{235}U. Despite broad agreement, comparison of the Huber ^{235}U model to the measured spectrum produces a χ^{2}/ndf=51.4/31, driven primarily by deviations in two localized energy regions. The measured ^{235}U spectrum shape is consistent with a deviation relative to prediction equal in size to that observed at low-enriched uranium power reactors in the ν[over ¯]_{e} energy region of 5-7 MeV.

6.
Phys Rev Lett ; 121(25): 251802, 2018 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-30608854

RESUMEN

This Letter reports the first scientific results from the observation of antineutrinos emitted by fission products of ^{235}U at the High Flux Isotope Reactor. PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, consists of a segmented 4 ton ^{6}Li-doped liquid scintillator detector covering a baseline range of 7-9 m from the reactor and operating under less than 1 m water equivalent overburden. Data collected during 33 live days of reactor operation at a nominal power of 85 MW yield a detection of 25 461±283 (stat) inverse beta decays. Observation of reactor antineutrinos can be achieved in PROSPECT at 5σ statistical significance within 2 h of on-surface reactor-on data taking. A reactor model independent analysis of the inverse beta decay prompt energy spectrum as a function of baseline constrains significant portions of the previously allowed sterile neutrino oscillation parameter space at 95% confidence level and disfavors the best fit of the reactor antineutrino anomaly at 2.2σ confidence level.

7.
Insect Mol Biol ; 26(2): 152-163, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27869336

RESUMEN

The development of insecticide resistance in insect pests of crops is a growing threat to sustainable food production, and strategies that slow the development of resistance are therefore urgently required. The insecticide synergist piperonyl butoxide (PBO) inhibits certain insect detoxification systems and so may delay the evolution of metabolic resistance. In the current study we characterized resistance development in the silverleaf whitefly, Bemisia tabaci, after selection with either a neonicotinoid (thiacloprid) or pyrethroid (alpha-cypermethrin) insecticide alone or in combination with PBO. Resistance development was significantly suppressed (> 60%) in the line selected with alpha-cypermethrin + PBO compared to the line selected with alpha-cypermethrin alone. RNA sequencing (RNAseq) analyses revealed an increase in frequency of a knock-down resistance mutation but no differentially expressed genes were identified that could explain the sensitivity shift. No significant difference was observed in the level of resistance between the thiacloprid and thiacloprid + PBO selected lines, and RNA sequencing (RNAseq) analyses revealed that the cytochrome P450 monooxygenase CYP6CM1, known to metabolize neonicotinoids, was significantly upregulated (>10-fold) in both lines. The findings of this study demonstrate that PBO used in combination with certain insecticides can suppress the development of resistance in a laboratory setting; however, the mechanism by which PBO supresses resistance development remains unclear.


Asunto(s)
Hemípteros/efectos de los fármacos , Insecticidas , Sinergistas de Plaguicidas/farmacología , Butóxido de Piperonilo/farmacología , Piretrinas , Animales , Evolución Molecular , Perfilación de la Expresión Génica , Técnicas de Genotipaje , Hemípteros/genética , Hemípteros/metabolismo , Resistencia a los Insecticidas/efectos de los fármacos , Selección Genética , Transcriptoma
8.
Phys Rev Lett ; 118(24): 242002, 2017 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-28665642

RESUMEN

We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.

9.
Insect Mol Biol ; 25(2): 171-80, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26790026

RESUMEN

Honey bees, Apis mellifera, are markedly less sensitive to neonicotinoid insecticides containing a cyanoimino pharmacophore than to those with a nitroimino group. Although previous work has suggested that this results from enhanced metabolism of the former by detoxification enzymes, the specific enzyme(s) involved remain to be characterized. In this work, a pretreatment of honey bees with a sublethal dose of thiacloprid resulted in induced insensitivity to the same compound immediately following thiacloprid feeding. A longer pretreatment time resulted in no, or increased, sensitivity. Transcriptome profiling, using microarrays, identified a number of genes encoding detoxification enzymes that were over-expressed significantly in insecticide-treated bees compared with untreated controls. These included five P450s, CYP6BE1, CYP305D1, CYP6AS5, CYP315A1, CYP301A1, and a carboxyl/cholinesterase (CCE) CCE8. Four of these P450s were functionally expressed in Escherichia coli and their ability to metabolize thiacloprid examined by liquid chromatography-mass spectrometry (LC-MS) analysis.


Asunto(s)
Abejas/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/genética , Inactivación Metabólica/genética , Anabasina/farmacología , Animales , Abejas/metabolismo , Sistema Enzimático del Citocromo P-450/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Insecticidas/farmacología , Neonicotinoides , Piridinas/farmacología , Tiazinas/farmacología , Activación Transcripcional/efectos de los fármacos
10.
Phys Rev Lett ; 116(24): 242501, 2016 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-27367385

RESUMEN

The standard model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the ß decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14 to 782 keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335±0.00005[stat]±0.00015[syst]. A second detector array of large area avalanche photodiodes directly detected photons from 0.4 to 14 keV. For this array, the spectral shape was consistent with theory, and the branching ratio was determined to be 0.00582±0.00023[stat]±0.00062[syst]. We report the first precision test of the shape of the photon energy spectrum from neutron radiative decay and a substantially improved determination of the branching ratio over a broad range of photon energies.

11.
Insect Mol Biol ; 23(4): 511-26, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24707894

RESUMEN

The pollen beetle Meligethes aeneus is the most important coleopteran pest in European oilseed rape cultivation, annually infesting millions of hectares and responsible for substantial yield losses if not kept under economic damage thresholds. This species is primarily controlled with insecticides but has recently developed high levels of resistance to the pyrethroid class. The aim of the present study was to provide a transcriptomic resource to investigate mechanisms of resistance. cDNA was sequenced on both Roche (Indianapolis, IN, USA) and Illumina (LGC Genomics, Berlin, Germany) platforms, resulting in a total of ∼53 m reads which assembled into 43 396 expressed sequence tags (ESTs). Manual annotation revealed good coverage of genes encoding insecticide target sites and detoxification enzymes. A total of 77 nonredundant cytochrome P450 genes were identified. Mapping of Illumina RNAseq sequences (from susceptible and pyrethroid-resistant strains) against the reference transcriptome identified a cytochrome P450 (CYP6BQ23) as highly overexpressed in pyrethroid resistance strains. Single-nucleotide polymorphism analysis confirmed the presence of a target-site resistance mutation (L1014F) in the voltage-gated sodium channel of one resistant strain. Our results provide new insights into the important genes associated with pyrethroid resistance in M. aeneus. Furthermore, a comprehensive EST resource is provided for future studies on insecticide modes of action and resistance mechanisms in pollen beetle.


Asunto(s)
Escarabajos/efectos de los fármacos , Escarabajos/genética , Sistema Enzimático del Citocromo P-450/genética , Inducción Enzimática/efectos de los fármacos , Resistencia a los Insecticidas/fisiología , Insecticidas/farmacología , Piretrinas/farmacología , Animales , Secuencia de Bases , Escarabajos/enzimología , Etiquetas de Secuencia Expresada , Resistencia a los Insecticidas/genética , Datos de Secuencia Molecular , Mutación , Transcriptoma , Canales de Sodio Activados por Voltaje/genética
12.
Acta Psychiatr Scand ; 129(3): 180-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24205846

RESUMEN

OBJECTIVE: Childhood maltreatment (CM) has been associated with several diseases in adult life, including diabetes, obesity and mental disorders. Inflammatory conditions have been postulated as possible mediators of this relationship. The aim was to conduct a systematic review regarding the association between CM and inflammatory markers in adulthood. METHOD: A literature search of the PubMed, ISI, EMBASE and PsychINFO databases was conducted. The key terms used were as follows: 'Child Maltreatment', 'Childhood Trauma', 'Early Life Stress', 'Psychological Stress', 'Emotional Stress', 'Child Abuse' and 'Child Neglect'. They were cross-referenced separately with the terms: 'C-reactive Protein (CRP)', 'Tumor Necrosis Factor', 'Cytokine', 'Interleukin', 'Inflammatory' and 'Inflammation'. RESULTS: Twenty articles remained in the review after exclusion criteria were applied. Studies showed that a history of CM was associated with increased levels of CRP, fibrinogen and proinflammatory cytokines. Increased levels of circulating CRP in individuals with a history of CM were the most robust finding among the studies. Data about anti-inflammatory mediators are still few and inconsistent. CONCLUSION: Childhood maltreatment is associated with a chronic inflammatory state independent of clinical comorbidities. However, studies are heterogeneous regarding CM assessment and definition. Important methodological improvements are needed to better understand the potential impact of CM on inflammatory response.


Asunto(s)
Biomarcadores , Maltrato a los Niños , Inflamación , Biomarcadores/sangre , Niño , Maltrato a los Niños/psicología , Humanos , Inflamación/sangre , Inflamación/etiología
13.
Insect Mol Biol ; 22(5): 485-96, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23889345

RESUMEN

Bemisia tabaci has developed high levels of resistance to many insecticides including the neonicotinoids and there is strong evidence that for some compounds resistance is stage-specific. To investigate the molecular basis of B. tabaci resistance to the neonicotinoid thiamethoxam we used a custom whitefly microarray to compare gene expression in the egg, nymph and adult stages of a thiamethoxam-resistant strain (TH-R) with a susceptible strain (TH-S). Gene ontology and bioinformatic analyses revealed that in all life stages many of the differentially expressed transcripts encoded enzymes involved in metabolic processes and/or metabolism of xenobiotics. Several of these are candidate resistance genes and include the cytochrome P450 CYP6CM1, which has been shown to confer resistance to several neonicotinoids previously, a P450 belonging to the Cytochrome P450s 4 family and a glutathione S-transferase (GST) belonging to the sigma class. Finally several ATP-binding cassette transporters of the ABCG subfamily were highly over-expressed in the adult stage of the TH-R strain and may play a role in resistance by active efflux. Here, we evaluated both common and stage-specific gene expression signatures and identified several candidate resistance genes that may underlie B. tabaci resistance to thiamethoxam.


Asunto(s)
Perfilación de la Expresión Génica , Hemípteros/genética , Resistencia a los Insecticidas/genética , Estadios del Ciclo de Vida , Nitrocompuestos , Oxazinas , Tiazoles , Transcriptoma/genética , Animales , Femenino , Resistencia a los Insecticidas/efectos de los fármacos , Estadios del Ciclo de Vida/efectos de los fármacos , Neonicotinoides , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tiametoxam , Transcriptoma/efectos de los fármacos
15.
Insect Mol Biol ; 20(6): 763-73, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21929695

RESUMEN

The brown planthopper, Nilaparvata lugens, is an economically significant pest of rice throughout Asia and has evolved resistance to many insecticides including the neonicotinoid imidacloprid. The resistance of field populations of N. lugens to imidacloprid has been attributed to enhanced detoxification by cytochrome P450 monooxygenases (P450s), although, to date, the causative P450(s) has (have) not been identified. In the present study, biochemical assays using the model substrate 7-ethoxycoumarin showed enhanced P450 activity in several resistant N. lugens field strains when compared with a susceptible reference strain. Thirty three cDNA sequences encoding tentative unique P450s were identified from two recent sequencing projects and by degenerate PCR. The mRNA expression level of 32 of these was examined in susceptible, moderately resistant and highly resistant N. lugens strains using quantitative real-time PCR. A single P450 gene (CYP6ER1) was highly overexpressed in all resistant strains (up to 40-fold) and the level of expression observed in the different N. lugens strains was significantly correlated with the resistance phenotype. These results provide strong evidence for a role of CYP6ER1 in the resistance of N. lugens to imidacloprid.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Hemípteros/enzimología , Imidazoles , Proteínas de Insectos/metabolismo , Insecticidas , Nitrocompuestos , Secuencia de Aminoácidos , Animales , Sistema Enzimático del Citocromo P-450/genética , ADN Complementario/química , Femenino , Dosificación de Gen , Hemípteros/genética , Proteínas de Insectos/genética , Resistencia a los Insecticidas/genética , Datos de Secuencia Molecular , Neonicotinoides , Reacción en Cadena de la Polimerasa
16.
Domest Anim Endocrinol ; 71: 106391, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31731250

RESUMEN

Corpus luteum (CL), a transient endocrine gland critical for reproductive cyclicity and pregnancy maintenance, is controlled by numerous regulatory factors. Although LH is widely recognized as the major regulator, other factors may also affect luteal functions. It has been demonstrated that FSH receptors (FSHR) are expressed not only in ovarian follicles but also in other tissues within the reproductive tract, including the CL. To evaluate FSHR expression in nontreated (nonsuperovulated; experiment 1) or FSH-treated (superovulated; experiment 2) sheep fed a control (C; maintenance), excess (O; 2 × C), or restricted (U; 0.6 × C) diet, CL were collected at the early, mid and/or late luteal phases (n = 5-7 per group). Protein and messenger RNA (mRNA) expression of FSHR were detected in the CL from all groups using immunohistochemistry followed by image analysis and quantitative RT-PCR, respectively. Follicle-stimulating hormone receptor was immunolocalized to steroidogenic small and large and nonsteroidogenic luteal cells. In both experiments, FSHR protein expression was not affected by stage of luteal development or diet. In experiment 1, expression of mRNA for all FSHR variants was greater (P <0.02 to 0.0003) at the late phase than mid or early luteal phase, and in experiment 2, it was greater (P < 0.001) at the mid than early luteal phase. Plane of nutrition did not affect FSHR mRNA expression. Comparison of FSH-treated with nontreated ewes demonstrated that FSH increased FSHR protein expression by 1.5- to 2-fold (P < 0.0001) in all groups, and mRNA expression by 7- to 30-fold (P < 0.001) for (1) FSHR-1 in all groups except U at the early luteal phase, (2) FSHR-2 in C, O, and U at the mid-phase, but not early luteal phase, and (3) FSHR-3 in U at the mid-luteal phase. Our data demonstrate that (1) FSHRs are expressed in ovine CL at several stages of luteal development, (2) FSHR protein expression does not change during the luteal phase and is not affected by diet, (3) FSHR mRNA expression not only depends on the stage of the estrous cycle but also not affected by diet in nonsuperovulated or superovulated ewes, and (4) in vivo FSH treatment enhanced FSHR protein and/or mRNA expression in the CL depending on diet and phase of the estrous cycle. Presence of FSHR in the CL indicates a regulatory role of FSH in luteal function in sheep. As very little is known about the possible role of FSH and FSHR in luteal functions, further studies should be undertaken to elucidate the endocrine, molecular, and cellular mechanisms of FSH effects on the CL.


Asunto(s)
Cuerpo Lúteo/metabolismo , Hormona Folículo Estimulante/farmacología , Receptores de HFE/metabolismo , Ovinos , Animales , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Estado Nutricional , Receptores de HFE/genética
17.
Phys Rev C ; 1012020.
Artículo en Inglés | MEDLINE | ID: mdl-33336123

RESUMEN

Reactor neutrino experiments have seen major improvements in precision in recent years. With the experimental uncertainties becoming lower than those from theory, carefully considering all sources of ν ¯ e is important when making theoretical predictions. One source of ν ¯ e that is often neglected arises from the irradiation of the nonfuel materials in reactors. The ν ¯ e rates and energies from these sources vary widely based on the reactor type, configuration, and sampling stage during the reactor cycle and have to be carefully considered for each experiment independently. In this article, we present a formalism for selecting the possible ν ¯ e sources arising from the neutron captures on reactor and target materials. We apply this formalism to the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory, the ν ¯ e source for the the Precision Reactor Oscillation and Spectrum Measurement (PROSPECT) experiment. Overall, we observe that the nonfuel ν ¯ e contributions from HFIR to PROSPECT amount to 1% above the inverse beta decay threshold with a maximum contribution of 9% in the 1.8-2.0 MeV range. Nonfuel contributions can be particularly high for research reactors like HFIR because of the choice of structural and reflector material in addition to the intentional irradiation of target material for isotope production. We show that typical commercial pressurized water reactors fueled with low-enriched uranium will have significantly smaller nonfuel ν ¯ e contribution.

18.
Trop Med Int Health ; 14(4): 396-403, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19254231

RESUMEN

OBJECTIVE: To investigate through countrywide sampling at 20 localities across the three different agro-climatic zones of Burkina Faso, the distribution of the acetylcholinesterase insensitive mutation ace-1(R), which confers resistance to organophosphates (OP) and carbamates (CM) insecticides in An. gambiae s.l. METHODS: Adult mosquitoes were collected by indoor aerosol spraying from August to October 2006. Specimens were identified to species by polymerase chain reaction (PCR) assay and characterized for the ace-1(R) mutation using a PCR-restriction fragment length polymorphism diagnostic. RESULTS: Collected mosquitoes were a mixture of An. gambiae s.s. and An. arabiensis across the Sudan (98.3%vs. 1.7%), Sudan-sahelian (78.6%vs. 21.4%) and the Sahel (91.5%vs. 8.5%) ecotypes. The An. gambiae S-form predominated in the Sudan sites from the West (69%vs. 31% for the M form) but was not found in the Sahel (100% M form). The ace-1(R) mutation was dispersed throughout the Sudan and Sudan-sahelian localities at moderate frequency (<50%) but was absent in the Sahel. It was far more prevalent in S form than M form mosquitoes (0.32 for the S form vs. 0.036 for the M form). No An. arabiensis was detected carrying the mutation. The geographic distribution of ace-1(R) in the Sudan and Sudan-sahelian correlated with the cotton growing areas dispersed throughout the two climatic zones. CONCLUSIONS: These results have special significance as OP and CM insecticides have been proposed as alternatives or additions to pyrethroids which are currently used exclusively in many vector control programmes.


Asunto(s)
Acetilcolinesterasa/genética , Anopheles/genética , Frecuencia de los Genes/genética , Resistencia a los Insecticidas/genética , Animales , Anopheles/enzimología , Burkina Faso , Mutación Puntual/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
19.
J Fish Biol ; 74(4): 763-72, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20735598

RESUMEN

Fundulus heteroclitus from six sites throughout the Hackensack Meadowlands District in northern NJ, U.S.A., were examined. Differences in behaviour (surfacing, conspicuousness and activity) were compared to gill infection intensity. Fish from populations infected with >1500 digenean metacercariae of Ascocotyle phagicola diminuta and Echinochasmus schwartzi, spent significantly more time at the water surface and exhibited significantly more conspicuous behaviour (e.g. jerking) than fish from less parasitized populations. This more conspicuous behaviour has the potential to increase trophic transmission of the parasite to its definitive wading-bird host.


Asunto(s)
Conducta Animal/fisiología , Enfermedades de los Peces/parasitología , Fundulidae/fisiología , Metacercarias/fisiología , Infecciones por Trematodos/veterinaria , Análisis de Varianza , Animales , Fundulidae/parasitología , Branquias/parasitología , Densidad de Población , Infecciones por Trematodos/parasitología
20.
Phys Rev C ; 100(1)2019.
Artículo en Inglés | MEDLINE | ID: mdl-35005330

RESUMEN

Neutron spin rotation is expected from quark-quark weak interactions in the standard model, which induce weak interactions among nucleons that violate parity. We present the results from an experiment searching for the effect of parity violation via the spin rotation of polarized neutrons in a liquid 4He medium. The value for the neutron spin rotation angle per unit length in 4He, d ϕ / d z = [ + 2.1 ± 8.3 (stat.) - 0.2 + 2.9 (sys.) ] × 10 - 7 rad/m, is consistent with zero. The result agrees with the best current theoretical estimates of the size of nucleon-nucleon weak amplitudes from other experiments and with the expectations from recent theoretical approaches to weak nucleon-nucleon interactions. In this paper we review the theoretical status of parity violation in the n → + 4He system and discuss details of the data analysis leading to the quoted result. Analysis tools are presented that quantify systematic uncertainties in this measurement and that are expected to be essential for future measurements.

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