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1.
Bull Entomol Res ; 107(2): 225-233, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27876100

RESUMO

Buenos Aires city is located near the southern limit of the distribution of Aedes aegypti (Diptera: Culicidae). This study aimed to assess long-term variations in the abundance of Ae. aegypti in Buenos Aires in relation to changes in climatic conditions. Ae. aegypti weekly oviposition activity was analyzed and compared through nine warm seasons from 1998 to 2014, with 200 ovitraps placed across the whole extension of the city. The temporal and spatial dynamics of abundances were compared among seasons, and their relation with climatic variables were analyzed. Results showed a trend to higher peak abundances, a higher number of infested sites, and longer duration of the oviposition season through subsequent years, consistent with a long-term colonization process. In contrast, thermal favorability and rainfall pattern did not show a consistent trend of changes. The long-term increase in abundance, and the recently documented expansion of Ae. aegypti to colder areas of Buenos Aires province suggest that local populations might be adapting to lower temperature conditions. The steadily increasing abundances may have implications on the risk of dengue transmission.


Assuntos
Aedes/fisiologia , Insetos Vetores , Adaptação Fisiológica , Animais , Argentina , Clima , Temperatura Baixa , Dengue/transmissão , Insetos Vetores/fisiologia , Oviposição , Dinâmica Populacional , Estações do Ano
2.
Phys Rev Lett ; 112(3): 030403, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24484124

RESUMO

We reveal universal dynamical scaling behavior across adiabatic quantum phase transitions in networks ranging from traditional spatial systems (Ising model) to fully connected ones (Dicke and Lipkin-Meshkov-Glick models). Our findings, which lie beyond traditional critical exponent analysis and adiabatic perturbation approximations, are applicable even where excitations have not yet stabilized and, hence, provide a time-resolved understanding of quantum phase transitions encompassing a wide range of adiabatic regimes. We show explicitly that even though two systems may traditionally belong to the same universality class, they can have very different adiabatic evolutions. This implies that more stringent conditions need to be imposed than at present, both for quantum simulations where one system is used to simulate the other and for adiabatic quantum computing schemes.

3.
J Fish Biol ; 84(2): 372-82, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24422902

RESUMO

Silvinichthys huachi new species, is described from a stream along the lower slope of the Andean Cordillera in the Provincia de San Juan, Argentina. It shares the distinctive modifications characteristic of Silvinichthys, but is distinguished from the four previously described congeners by the combination of a lack of the pelvic fin and the pelvic girdle, details of pigmentation and various meristic and morphometric features. Silvinichthys huachi is apparently endemic to the type locality situated within an arid region of western central Argentina in the Andino Cuyana Province. Major gaps in the range of species of Silvinichthys may indicate that the origin of the genus predates the uplift events that subdivided drainages along the eastern slopes of the Andean Cordillera in west central Argentina. Silvinichthys huachi is hypothesized to be the sister species of Silvinichthys bortayro.


Assuntos
Peixes-Gato/anatomia & histologia , Nadadeiras de Animais , Animais , Argentina , Pigmentação
4.
Opt Express ; 20(4): 4470-83, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22418206

RESUMO

The dependence of the excitonic two-photon absorption on the quantum correlations (entanglement) of exciting biphotons by a semiconductor quantum well is studied. We show that entangled photon absorption can display very unusual features depending on space-time-polarization biphoton parameters and absorber density of states for both bound exciton states as well as for unbound electron-hole pairs. We report on the connection between biphoton entanglement, as quantified by the Schmidt number, and absorption by a semiconductor quantum well. Comparison between frequency-anti-correlated, unentangled and frequency-correlated biphoton absorption is addressed. We found that exciton oscillator strengths are highly increased when photons arrive almost simultaneously in an entangled state. Two-photon-absorption becomes a highly sensitive probe of photon quantum correlations when narrow semiconductor quantum wells are used as two-photon absorbers.

5.
Sci Rep ; 9(1): 17772, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780693

RESUMO

We identify different schemes to enhance the violation of Leggett-Garg inequalities in open many-body systems. Considering a nonequilibrium archetypical setup of quantum transport, we show that particle interactions control the direction and amplitude of maximal violation, and that in the strongly-interacting and strongly-driven regime bulk dephasing enhances the violation. Through an analytical study of a minimal model we unravel the basic ingredients to explain this decoherence-enhanced quantumness, illustrating that such an effect emerges in a wide variety of systems.

6.
Clin Microbiol Infect ; 24(12): 1342.e5-1342.e8, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29933050

RESUMO

The identification of Nocardia isolates still represents a challenge for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) despite its acceptance for most bacterial and fungal isolates. In this study we evaluate the identification of Nocardia isolates using direct spotting and an updated database. Overall, 82 Nocardia isolates belonging to 13 species were identified by DNA sequence analysis of the 16S rRNA and secA1 genes. Nine of these well-characterized isolates from 6 Nocardia species were used to create an in-house library. The remaining 73 isolates were directly spotted on the target plate and on-plate protein extraction was performed. The protein spectra obtained were analyzed by MALDI-TOF MS using the BDAL database (Bruker Daltonics) updated with 6,903 MSPs or the combination of this commercial database and our in-house library. As a result, the use of the commercial database alone and in combination with the in-house library yielded 94.5% and 95.9% of correct species-level identifications, respectively, No isolate was misidentified at the genus level with either database. Besides, the use of the in-house library allowed the species-level identification of a N. otitidiscaviarum isolate that could only be identified at the genus-level with a score value <1.6 using the commercial database. In conclusion, the implementation of the direct spotting method and the in-house database provided a high rate of correct species assignment of Nocardia isolates despite the low number of isolates added. Further addition of well-characterized Nocardia isolates may ensure the rapid, accurate and inexpensive identification of most isolates encountered in the routine of the microbiology laboratory.


Assuntos
Nocardiose/microbiologia , Nocardia/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Bases de Dados de Ácidos Nucleicos , Biblioteca Gênica , Humanos , Nocardia/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Clin Microbiol Infect ; 24(6): 599-603, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29174730

RESUMO

BACKGROUND: The implementation of MALDI-TOF MS for microorganism identification has changed the routine of the microbiology laboratories as we knew it. Most microorganisms can now be reliably identified within minutes using this inexpensive, user-friendly methodology. However, its application in the identification of mycobacteria isolates has been hampered by the structure of their cell wall. Improvements in the sample processing method and in the available database have proved key factors for the rapid and reliable identification of non-tuberculous mycobacteria isolates using MALDI-TOF MS. AIMS: The main objective is to provide information about the proceedings for the identification of non-tuberculous isolates using MALDI-TOF MS and to review different sample processing methods, available databases, and the interpretation of the results. SOURCES: Results from relevant studies on the use of the available MALDI-TOF MS instruments, the implementation of innovative sample processing methods, or the implementation of improved databases are discussed. CONTENT: Insight about the methodology required for reliable identification of non-tuberculous mycobacteria and its implementation in the microbiology laboratory routine is provided. IMPLICATIONS: Microbiology laboratories where MALDI-TOF MS is available can benefit from its capacity to identify most clinically interesting non-tuberculous mycobacteria in a rapid, reliable, and inexpensive manner.


Assuntos
Micobactérias não Tuberculosas/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Técnicas Bacteriológicas , Humanos , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Fluxo de Trabalho
9.
Med. infant ; 23(2): 108-116, junio 2016. tab
Artigo em Espanhol | LILACS | ID: biblio-882252

RESUMO

En adultos y niños con trasplante renal (TxR) la sobrevida de paciente e injerto ha mejorado. En Argentina no existen datos de sobrevida en niños con TxR en diferentes décadas. El objeto de este trabajo fue valorar en niños con TxR sobrevida de paciente e injerto y analizar causas de muerte, perdida de injerto y factores de riesgo de pérdida. Dado que desde el año 2001 se unificaron prácticas de diagnóstico y tratamiento, se compararon dos periodos: 1988-2000 y 2001-2015. Se incluyeron 773 niños. A 1, 3, 5, 7 y 10 años, En TxR de DV (n=327), la sobrevida del paciente fue de 99%, 99%, 98%, 95%, 95% vs 100% y 96%, 96%, 96% y 96% (p=0.74); la del injerto de 97%, 91%, 85%, 78% y 67% vs 95%, 88%, 85%, 81% y 76% (p=0.81). En TxR de DC (n=446) la sobrevida de paciente fue de 97%, 93%, 90%, 89% y 87% en el 1er. periodo vs. 100%, 99% y 98% 98% y 98% en el 2do (p<0.001); la del injerto de 83%, 75%, 68%, 64% y 52% vs. 95%, 87%, 83%, 76% y 61% respectivamente (p<0. 001). El Rechazo Crónico fue la 1er causa de perdida (61% vs 62%); la 2da la muerte del paciente con injerto funcionante. La sepsis bacteriana fue la 1era causa de muerte (56% vs 67%). Ningún niño falleció por neoplasia entre el 2001 y 2015. En DV, fueron predictores de perdida de injerto: DGF (HR: 4.8; p<0.001), edad al TxR > 12 años (HR: 2.7; p=0.002) y RA tardío (HR: 2.1; p=0.009). En DC la necesidad de diálisis en la 1er semana post TxR (DGF): (HR: 4.4; p<0.001), el rechazo agudo (RA) tardío (HR: 3.7; p<0.001), GSFS como causa de IRC (HR: 2.5; p=0.01), y RA temprano (HR: 2.2; p=0.02). Conclusión: En el 2do periodo la sobrevida de paciente e injerto los TxR con DC mejoro, y en los TxR con DV no tuvo cambios. El rechazo crónico continúa siendo la 1era causa de perdida. Ningún paciente tuvo neoplasia (AU)


Patient and graft survival in kidney transplantation (KTx) has improved. In Argentina there are no data comparing transplant outcomes in children over different eras. The aim of this study was to evaluate patient and graft survival in children with KTx and to analyze cause of death, graft loss, and risk factors of graft loss. As diagnostic and treatment practices were unified in 2001, two periods were compared: 1988-2000 and 2001-2015. Overall, 773 children were included. Survival at 1, 3, 5, 7, and 10 years after a living-related donor (LRD) KTx was 99%, 99%, 98%, 95%, 95% vs 100% y 96%, 96%, 96% and 96% (p=0.74); graft survival was 97%, 91%, 85%, 78% y 67% vs 95%, 88%, 85%, 81%, and 76% (p=0.81). Patient survival after deceased donor (DD) KTx (n=446) was 97%, 93%, 90%, 89%, and 87% in the 1st period vs. 100%, 99% y 98% 98%, and 98% in the 2nd (p<0.001); graft survival was 83%, 75%, 68%, 64%, and 52% vs. 95%, 87%, 83%, 76%, and 61%, respectively (p<0. 001). Chronic rejection was the first cause of graft loss (61% vs 62%); the second was death of the patient with a functioning graft. Bacterial sepsis was the first cause of death (56% vs 67%). None of the patients died because of malignancies between 2001 and 2015. Among LRD transplants predicting factors of graft loss were: DGF (HR: 4.8; p<0.001), age at KTx >12 years (HR: 2.7; p=0.002), and late acute rejection (AR) (HR: 2.1; p=0.009). Among DD need for dialysis in the first week post-KTx (DGF): (HR: 4.4; p<0.001), late AR (HR: 3.7; p<0.001), FSGS-related CFR (HR: 2.5; p=0.01), and early AR (HR: 2.2; p=0.02). Conclusion: In the second period patient and graft survival after DD improved, while that of KTx with LRD remained unchanged. Chronic rejection continues being the first cause of graft loss. None of the patients developed malignancies.


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Causas de Morte , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/terapia , Sobrevivência de Enxerto , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Estudos Retrospectivos
11.
Phys Rev B Condens Matter ; 42(11): 7006-7014, 1990 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9994824
13.
Phys Rev B Condens Matter ; 40(6): 3955-3961, 1989 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9992368
14.
Phys Rev B Condens Matter ; 44(1): 399-402, 1991 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9998261
17.
Phys Rev Lett ; 87(24): 246403, 2001 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-11736522

RESUMO

We report on the transfer of coherence from a quantum-well electron-hole condensate to the light it emits. As a function of density, the coherence of the electron-hole-pair system evolves from being full for the low-density Bose-Einstein condensate to a chaotic behavior for a high-density BCS-like state. This degree of coherence is transferred to the light emitted in a damped oscillatory way in the ultrafast regime. Additionally, the photon field exhibits squeezing properties during the transfer time. Our results suggest a new type of ultrafast experiments for detecting electron-hole-pair condensation.

18.
Med. infant ; 16(2): 110-117, jun. 2009. graf, ilus
Artigo em Espanhol | LILACS | ID: lil-538112

RESUMO

El trasplante cardíaco se ha transformado en la actualidad en la estrategia quirúrgica de elección para la insuficiencia cardíaca terminal en la infancia. Objetivo general: analizar la experiencia del Programa de Trasplante Cardíaco del Hospital de Pediatría Juan P. Garrahan. Objetivos especificos: Describir diagnósticos y características de los pacientes inscriptos para transplante cardíaco. Evaluar la sobrevida en lista de espera. Identificar aquellos que requirieron corazón artificial. Evaluar el uso e impacto de esta tecnología en la sobrevida de los pacientes. Evaluar la sobrevida de los pacientes trasplantados. Material y Métodos: Con un diseño descriptivo, retrospectivo, transversal y observacional se analizó la población inscripta en lista de espera entre agosto 2000 a agosto 2008 tomando en cuenta variables como: sexo, procedencia, edad, peso, diagnóstico, categoría de ingreso, tiempo en lista de espera y evento: a) fallecido, b)trasplante, c)implante de asistencia mecánica ventricular (AMV, corazón artificial) Resultados: Se inscribieron 47 pacientes; el diagnóstico más frecuente fue la miocardiopatía en el 70 por ciento. La mediana de permanencia en lista de espera fue de 2 meses (r o-68). Dieciocho fallecieron sin haber sido trasplantados. 12 continúan en lista de espera y 16 fueron trasplantados. La sobrevida post quirúrgica inmediata fue del 75 por ciento. De los pacientes en seguimiento la sobrevida al año es del 100 por ciento y a los 5 años del 85 por ciento. En el 2006 se incorpora la AMW para pacientes terminales, la cual impacta en la mortalidad en lista de epera disminuyéndola del 43 por ciento al 22 por ciento. Conclusiones: El trasplante cardiaco en la edad pediátrica es una opción adecuada para pacientes sin otra alternativa terapéutica. Un programa de trasplante cardíaco infantil, sostenido en un hospital público facilita la accesibilidad universal al mismo. La falta de donantes adecuados para la edad pediátrica.


Assuntos
Masculino , Feminino , Lactente , Pré-Escolar , Cardiomiopatias , Cuidados Pós-Operatórios , Doente Terminal , Avaliação de Programas e Projetos de Saúde , Seleção do Doador , Transplante de Coração/estatística & dados numéricos , Transplante de Coração/mortalidade , Transplante de Coração/métodos , Transplante de Coração , Epidemiologia Descritiva , Estudos Retrospectivos , Estudos Observacionais como Assunto
20.
Rev. méd. Chile ; 132(4): 467-478, abr. 2004. tab, graf
Artigo em Espanhol | LILACS | ID: lil-362912

RESUMO

Background: The real prevalence of dementia in a given population must be determined through prevalence studies, using validated screening tests. Aim: To validate and determine cutoff points for a cognitive impairment screening test composed by the Folstein Mini Mental State Examination (MMSE) and Pfeffer Functional Activities Questionnaire (PFAQ). Material and methods: Validation of the diagnostic test in a sample of 100 subjects over 65 years old (85 from the project ½Age associated dementias¼ and 15 with a confirmed diagnosis of dementia). All were subjected to a complete neuropsychological test by a trained neurologist, that constituted the ½gold standard¼ for the diagnosis of dementia. An independent interviewer applied the MMSE to the subjects and the PFAQ to a next of kin informer. Cutoff points were calculated using ROC curves. The points with the better equilibrium between sensitivity and specificity were selected, considering differences in results between groups with low and high educational level. Results: The cutoff point for MMSE was 21/22, with a sensitivity of 93.6 per cent (95 per cent CI 70.6-99.7per cent) and a specificity of 46.1per cent (95per cent CI 34.7-57.8 per cent). The figure for PFAQ was 5/6, with a sensitivity of 89.2per cent (95per cent CI 70.6-99.7per cent) and a specificity of 70.7per cent (95 per cent CI 58.9-80.3 per cent). The combination of both instruments gave a sensitivity of 94.4per cent (95 per cent CI 58.9-80.3 per cent) and a specificity of 83.3 per cent (95 per cent CI 72.3-90.7per cent). Conclusions: This screening test, using MMSE and PFAQ, has a good sensitivity and specificity for the diagnosis of dementia in Chile. Being simple and of low cost, it can be applied in primary health care.


Assuntos
Humanos , Masculino , Feminino , Idoso , Demência/diagnóstico , Programas de Rastreamento/instrumentação , Programas de Rastreamento , Chile/epidemiologia , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia
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