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1.
Rev. Fac. Odontol. (B.Aires) ; 37(87): 79-85, 2022. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1551407

RESUMO

La Caries de la Infancia Temprana (CIT) se ha descrito como una patología de origen multifactorial en niños hasta los 71 meses de edad. Se considera como Ca-ries de la Infancia Temprana Severa (CITS) cuando a los 3 años el índice ceod es ≥ 4; a los 4 años, ≥ 5, y a los 5 años ≥ 6. La rehabilitación de las lesiones provo-cadas por esta patología puede ser compleja debido a la calidad y cantidad de estructura remanente y a la edad de los pacientes afectados. Objetivos: Estimar la frecuencia de CIT y CITS en niños menores a 72 me-ses que concurrieron para su atención, e identificar el tipo de práctica realizada, y la adhesión al trata-miento. Métodos: Diseño retrospectivo observacional sobre las historias clínicas de pacientes menores a 72 meses asistidos por los cursantes de la Especiali-zación en Odontopediatría, entre febrero 2021 y julio 2022. Resultados: La muestra quedó constituida por 101 niños, de 46+13,5 meses. El 91% presentó CITS. La totalidad de los pacientes mantuvieron lactancia nocturna prolongada después del año, siendo en el 72,3% a libre demanda durante el sueño, en un perío-do de 23+6 meses. Se registró un total de 1010 lesio-nes de caries. El 29,3% de los pacientes abandonaron el tratamiento. Conclusiones: La mayor parte de los niños presentaron Caries de la Infancia Temprana Severa, con altos valores de patología y lactancia noc-turna prolongada a libre demanda después del año Los tratamientos recomendados en estos casos son muy prolongados y requieren de prácticas invasivas, complejas y de alto costo, lo que provoca el abandono del tratamiento (AU)


Early childhood caries (ECC) is defined as a multifactorial disease in children 71 months of age or younger. When the dmft index is ≥4 (age 3), ≥5 (age 4), or ≥6 (age 5) it is referred to as Severe early childhood caries (SECC). Management of ECC is complex due to the quality and quantity of remaining structure of teeth at an early age. Objectives: To estimate the frequency of ECC and SECC in children < 72 months of age undergoing comprehensive treatment, to identify the type of treatment provided and treatment compliance. Methods: Retrospective observational design on dental records of patients under 72 months of age treated by Pediatric Dentistry Specialty Program students between February 2021 and July 2022. Results: The sample included 101 children, mean age 46+13.5 months, 91% of patients with SECC. All patients were fed nightly for over 1 year, 72.3% of whom were fed nightly on demand over a period of 23±6 months. A total of 1010 caries lesions were detected. 29.3% of children discontinued treatment. Conclusions: Most of the children presented severe early childhood caries with high values of pathology and prolonged nocturnal breastfeeding on demand after one year. The recommended treatments in these cases are very long and require invasive, complex and expensive practices, which causes abandonment of the treatment (AU)


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Dente Decíduo/lesões , Assistência Odontológica para Crianças/métodos , Cárie Dentária/epidemiologia , Argentina/epidemiologia , Faculdades de Odontologia/estatística & dados numéricos , Aleitamento Materno/efeitos adversos , Lactação , Estudos Retrospectivos , Recusa do Paciente ao Tratamento/estatística & dados numéricos , Cárie Dentária/terapia , Cooperação e Adesão ao Tratamento
2.
Neotrop Entomol ; 49(3): 353-360, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32078137

RESUMO

Copitarsia sp. (Hampson) (Lepidoptera: Noctuidae: Cuculliinae) is a quarantine pest in different countries and affects diverse crops of economic importance in South America. The development of ethological control strategies is an important issue that requires knowing the reproductive behavior of the species involved. Therefore, the aim of this study was to establish the reproductive behavior of Copitarsia uncilata (Burgos & Leiva) and to evaluate the attractiveness of synthetic pheromone compounds under laboratory conditions. Observations of nocturnal reproductive behavior of males and females were performed for 7 days in order to register the courtship, mating, and oviposition time. Once the period of the highest reproductive activity was identified, flight behavior and attraction of virgin males were evaluated in a wind tunnel towards synthetic compounds previously reported as commercial pheromones for Copitarsia species, namely (Z)-tetradec-9-enyl acetate (Z9-14Ac), (Z)-tetradec-9-enol (Z9-14OH), and their mixture (Z9-14Ac + Z9-14OH at 4:1 ratio), in comparison with virgin females and clean air flow. We observed that reproductive behavior occurs during the first third of the scotophase and begins on the second day after adult emergence. Highest proportion of courtship and mating occurs on days 2 and 3 after emergence, and oviposition starts the night immediately after the first mating. Wind tunnel assessments showed that males were highly attracted to calling females compared with the blend of synthetic pheromone compounds, with 89% and 12% of males landing at the source, respectively. Moreover, males also showed a low response to the isolated compounds (Z9-14Ac 14% and Z9-14OH 4%).


Assuntos
Mariposas/fisiologia , Atrativos Sexuais/química , Comportamento Sexual Animal , Animais , Feminino , Voo Animal , Masculino , Oviposição
3.
Phys Rev Lett ; 122(25): 251801, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31347897

RESUMO

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.

5.
Phys Rev Lett ; 119(8): 082001, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28952766

RESUMO

Charged-current ν_{µ} interactions on carbon, iron, and lead with a final state hadronic system of one or more protons with zero mesons are used to investigate the influence of the nuclear environment on quasielasticlike interactions. The transferred four-momentum squared to the target nucleus, Q^{2}, is reconstructed based on the kinematics of the leading proton, and differential cross sections versus Q^{2} and the cross-section ratios of iron, lead, and carbon to scintillator are measured for the first time in a single experiment. The measurements show a dependence on the atomic number. While the quasielasticlike scattering on carbon is compatible with predictions, the trends exhibited by scattering on iron and lead favor a prediction with intranuclear rescattering of hadrons accounted for by a conventional particle cascade treatment. These measurements help discriminate between different models of both initial state nucleons and final state interactions used in the neutrino oscillation experiments.

6.
Phys Rev Lett ; 119(1): 011802, 2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28731762

RESUMO

Neutral-current production of K^{+} by atmospheric neutrinos is a background in searches for the proton decay p→K^{+}ν[over ¯]. Reactions such as νp→νK^{+}Λ are indistinguishable from proton decays when the decay products of the Λ are below detection threshold. Events with K^{+} are identified in MINERvA by reconstructing the timing signature of a K^{+} decay at rest. A sample of 201 neutrino-induced neutral-current K^{+} events is used to measure differential cross sections with respect to the K^{+} kinetic energy, and the non-K^{+} hadronic visible energy. An excess of events at low hadronic visible energy is observed relative to the prediction of the neut event generator. Good agreement is observed with the cross section prediction of the genie generator. A search for photons from π^{0} decay, which would veto a neutral-current K^{+} event in a proton decay search, is performed, and a 2σ deficit of detached photons is observed relative to the genie prediction.

7.
Phys Rev Lett ; 117(11): 111801, 2016 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-27661679

RESUMO

The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current π^{0} production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26±0.02(stat.)±0.08(sys.)×10^{-39} cm^{2}. The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive π^{0} production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino-oscillation experiments searching for ν_{µ} to ν_{e} oscillations.

8.
Phys Rev Lett ; 117(6): 061802, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27541459

RESUMO

Neutrino-induced charged-current coherent kaon production ν_{µ}A→µ^{-}K^{+}A is a rare, inelastic electroweak process that brings a K^{+} on shell and leaves the target nucleus intact in its ground state. This process is significantly lower in rate than the neutrino-induced charged-current coherent pion production because of Cabibbo suppression and a kinematic suppression due to the larger kaon mass. We search for such events in the scintillator tracker of MINERvA by observing the final state K^{+}, µ^{-}, and no other detector activity, and by using the kinematics of the final state particles to reconstruct the small momentum transfer to the nucleus, which is a model-independent characteristic of coherent scattering. We find the first experimental evidence for the process at 3σ significance.

9.
Neotrop Entomol ; 45(6): 734-739, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27379761

RESUMO

In Colombia, Copitarsia uncilata Burgos & Leiva has been reported as a pest of ornamental flowers. The leafworm causes serious economic losses to farmers because the shipments are intercepted at the detection sites. The identification and subsequent synthesis of the sex pheromone compounds can lead to the use of semiochemicals as an important strategy to complement the pest management. This paper identifies and characterizes the chemical components of the female sexual gland of C. uncilata at three different age stages in order to relate the effect of age on the gland extract composition. Eggs and larvae were collected from commercial crops. The specimens were reared and sexed. Pheromone glands of intact females were excised at (a) 1-2, (b) 3-4, and (c) 5-6 days old. The extracts were analyzed using GC-MS after two extraction time points: 20 min and 8 days. The extracts from the third age stage showed an increase in concentration for 35% of the compounds after 8 days of storage. The relative abundance as a function of the female age showed two trends: an upward trend, where the relative abundances of the compounds increased through the age stages, while some compounds shown a downward trend. Within the first trend, mostly of the compounds were found to be related with infochemicals type structures, where tetradec-9-en-1-yl acetate (within several C-14 long-chain alcohols) is the main one. The 9-14:Ac quadrupled concentration through the ages is possibly related to the increased length of calling period as female moth age.


Assuntos
Lepidópteros/química , Feromônios/química , Atrativos Sexuais/química , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva , Mariposas
10.
Phys Rev Lett ; 116(8): 081802, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26967410

RESUMO

The first direct measurement of electron neutrino quasielastic and quasielasticlike scattering on hydrocarbon in the few-GeV region of incident neutrino energy has been carried out using the MINERvA detector in the NuMI beam at Fermilab. The flux-integrated differential cross sections in the electron production angle, electron energy, and Q^{2} are presented. The ratio of the quasielastic, flux-integrated differential cross section in Q^{2} for ν_{e} with that of similarly selected ν_{µ}-induced events from the same exposure is used to probe assumptions that underpin conventional treatments of charged-current ν_{e} interactions used by long-baseline neutrino oscillation experiments. The data are found to be consistent with lepton universality and are well described by the predictions of the neutrino event generator GENIE.

11.
Phys Rev Lett ; 116(7): 071802, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943528

RESUMO

Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{µ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

12.
Phys Rev Lett ; 112(23): 231801, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24972195

RESUMO

We present measurements of ν(µ) charged-current cross section ratios on carbon, iron, and lead relative to a scintillator (CH) using the fine-grained MINERvA detector exposed to the NuMI neutrino beam at Fermilab. The measurements utilize events of energies 2

13.
Phys Rev Lett ; 113(26): 261802, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615308

RESUMO

Neutrino-induced coherent charged pion production on nuclei νµA→µ(±)π(∓)A is a rare, inelastic interaction in which a small squared four-momentum |t| is transferred to the recoil nucleus, leaving it intact in the reaction. In the scintillator tracker of MINERvA, we remove events with evidence of particles from nuclear breakup and reconstruct |t| from the final-state pion and muon. We select low |t| events to isolate a sample rich in coherent candidates. By selecting low |t| events, we produce a model-independent measurement of the differential cross section for coherent scattering of neutrinos and antineutrinos on carbon. We find poor agreement with the predicted kinematics in neutrino generators used by current oscillation experiments.

14.
Phys Rev Lett ; 111(2): 022501, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23889388

RESUMO

We have isolated ν(µ) charged-current quasielastic (QE) interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross section, dσ/dQ², and compare to several theoretical models of QE scattering. Good agreement is obtained with a model where the nucleon axial mass, M(A), is set to 0.99 GeV/c² but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q² favor this interpretation over an alternative in which the axial mass is increased.

15.
Phys Rev Lett ; 111(2): 022502, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23889389

RESUMO

We report a study of ν(µ) charged-current quasielastic events in the segmented scintillator inner tracker of the MINERvA experiment running in the NuMI neutrino beam at Fermilab. The events were selected by requiring a µ- and low calorimetric recoil energy separated from the interaction vertex. We measure the flux-averaged differential cross section, dσ/dQ², and study the low energy particle content of the final state. Deviations are found between the measured dσ/dQ² and the expectations of a model of independent nucleons in a relativistic Fermi gas. We also observe an excess of energy near the vertex consistent with multiple protons in the final state.

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