Sorting on periodic surfaces

Particles moving on crystalline surfaces and driven by external forces or flow fields can acquire velocities along directions that deviate from that of the external force. This effect depends upon the characteristics of the particles, most notably particle size or particle index of refraction, and can therefore be (and has been) used to sort different particles. We introduce a simple model for particles subject to thermal fluctuations and moving in appropriate potential landscapes. Numerical results are compared to recent experiments on landscapes produced with holographic optical tweezers and microfabricated technology. Our approach clarifies the relevance of different parameters, the direction and magnitude of the external force, particle size, and temperature

Transport and diffusion on crystalline surfaces under external forces

We present a numerical study of classical particles obeying a Langevin equation and moving on a solid crystalline surface under an external force that may either be constant or modulated by periodic oscillations. We focus on the particle drift velocity and diffusion. The roles of friction and equilibrium thermal fluctuations are studied for two nonlinear dynamical regimes corresponding to low and to high but finite friction. We identify a number of resonances and antiresonances, and provide phenomenological interpretations of the observed behaviourPeer ReviewedPostprint(published version

Cardiopatías congénitas en el perro : conducto arterioso persistente, estenosis pulmonar y estenosis aórtica

En el presente artículo se describen los hallazgos clínicos, radiológicos, electrocardiográficos y ecográficos de las principales cardiopatías congénitas en el perro de acuerdo con una serie de casos clínicosClinical signs and radiological, electro and echocardiographic findings of the main congenital heart diseases in the dog are described in this paper based on c1inicalcases

Vítreo primario hiperplásico persistente y anomalías asociadas en un Husky siberiano

Se describe el caso clínico de una perra Husky siberiano que acudio a consulta para una evaluacion ocular porque el ojo derecho mostraba aspecto blanquecino. El diagnostico de vitreo primario hiperplastico persistente se efectuo mediante ultrasonografia bidimensional y Doppler color

Disautonomía felina

En el presente trabajo, se efectúa una revisión completa del síndrome disautonomía felina, así como la descripción de un caso clínico correspondiente a un gato macho de 11 meses de edad, junto con los medios de diagnóstico utilizado.At the present research a review ol the dysautonomia feline syndrome is included with the description of a clinical case in a male cat of 11 months of age

Bloqueo atrioventricular completo en un perro : tratamiento mediante la implantación de un marcapasos endovenosos permanente

Una perra Labrador Retriever presentaba una historia de síncopes, fatiga e intolerancia al ejercicio debida a un bloqueo atrioventricular completo. Debido a que no respondía a la terapia médica (terbutalina, teofilina y posteriormente atropina), fue remitida al Hospital Clínico Veterinario de la Universidad de Murcia con el fin de considerar la implantación de un marcapasos. Las radiografías de tórax mostraron aumento global de la silueta cardiaca y la ecocardiografía puso de manifiesto, además, ligera regurgitación de válvulasatrioventriculares. Se le implantó un marcapasos endovenoso permanente unipolar con modo VVI bajo anestesia general, guiando el cable hacia el ventrículo derecho mediante fluoroscopia con amplificador de imagen. Ocho meses después de la implantación, no se han producido complicaciones y el marcapasos funciona según los parámetros programados.

Age-performance and intensity of grooming behavior toward Varroa destructor in resistant and susceptible Apis mellifera colonies

Grooming behavior confers resistance to honey bees against Varroa destructor, being of interest to social immunity studies and breeding programs. The objective of this study was to characterize at the individual level the grooming behavior of mite-resistant (R) and susceptible (S) A. mellifera stocks from Argentina. Assays were performed in experimental arenas by applying two treatments to nurse bees: (1) placing a V. destructor mite on the bee’s thorax and (2) touching the bee with a paintbrush. Grooming reactions were recorded on bees from both stocks at the ages of 6, 10, and 14 days after emergence. R bees exhibited lower time of first response against the mite, performed more cleaning attempts, and used all their legs with a higher probability compared to S bees. The same pattern was evident when younger and older bees from the R stock were compared. The results demonstrate that bee age and genetic origin are critical factors of grooming behavior in honey bees.Fil: Russo, Romina Maria. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo; ArgentinaFil: Landi, Lucas. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Muntaabski, Irina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo; ArgentinaFil: Liendo, María Clara. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo; ArgentinaFil: Pietronave, Hernán Pablo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Reconquista; ArgentinaFil: Merke, Julieta. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Rodríguez, Graciela A.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Hilario Ascasubi; ArgentinaFil: Palacio, María A.. Universidad Nacional de Mar del Plata; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Basilio, Alicia Mabel. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Lanzavecchia, Silvia Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo; ArgentinaFil: Scannapieco, Alejandra Carla. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo; Argentin

Impact of the foliar application of nanoparticles, sulfate and iron chelate on the growth, yield and nitrogen assimilation in green beans

Nano-fertilizers (Nfs) have the potential to revolutionize agricultural systems through nanostructures ranging from 1 to 100 nm that address environmental responses and a more targeted biological demand. The purpose of this work was to study the impact of the foliar application of nanoparticles (NPs), sulfate and iron chelate on the growth, yield and assimilation of nitrogen in green beans. The iron was applied foliar in three different ways: Iron oxide nanoparticles (Fe2O3), ferric sulfate (Fe2(SO4)3) and iron chelate (Fe-EDDHA) in doses of 0, 25, 50, 100 and 200 ppm. The treatments that produced a higher total biomass increase were NPs and Fe-EDDHA at 50 ppm, with increases of 37% and 47% respectively compared to the control (with no application of Fe). Regarding the in vivo nitrate reductase activity, significant differences were obtained, particularly in the NPs and Fe-EDDHA treatment, with increases of 71% and 72% respectively. NPs at low doses favored maximum fruit production with increases of 88% in comparison to the control. Finally, it is concluded that the optimal doses that enhanced total biomass, production and assimilation of nitrogen were Fe2(SO4)3 at 25 ppm, Fe-EDDHA at 100 ppm and Fe2O3 at 25 ppm. The efficiency of foliar absorption of iron was found in treatments with Fe2O3 at 50 and 100 ppm. The foliar absorption efficiency of NPs offers sustainable alternatives to increase the productivity of the green bean

Should phenotype of previous preterm birth influence management of women with short cervix in subsequent pregnancy? Comparison of vaginal progesterone and Arabin pessary

Objective: To investigate whether the classification of a previous spontaneous preterm birth (sPTB) as preterm labor (PTL) with intact membranes (IM) or as preterm prelabor rupture of membranes (PPROM) impacts the efficacy of cervical pessary or vaginal progesterone for prevention of sPTB in pregnant women with short cervix on transvaginal ultrasound. Methods: This was a retrospective cohort study of asymptomatic high-risk singleton pregnancies with a short cervix and history of sPTB, treated using Arabin pessary or vaginal progesterone for primary PTB prevention, conducted at four European hospitals. A log-rank test on Kaplan-Meier curves was used to assess the difference in performance of pessary and progesterone, according to history of PTL-IM or PPROM. Linear regression analysis was used to evaluate significant predictors of gestational age at delivery. Results: Between 2008 and 2015, 170 women were treated with a pessary and 88 with vaginal progesterone. In women treated with a pessary, rate of sPTB < 34 weeks was 16% in those with a history of PTL-IM and 55% in those with a history of PPROM. In women treated with progesterone, rate of sPTB < 34 weeks was 13% in those with a history of PTL-IM and 21% in those with a history of PPROM. Treatment with a pessary resulted in earlier delivery in women with previous PPROM than in any other subgroup (P < 0.0001). Linear regression analysis showed a clear effect of PPROM history (P < 0.0001), combination of PPROM history and treatment (P = 0.0003) and cervical length (P = 0.0004) on gestational age at birth. Conclusions: Cervical pessary may be a less efficacious treatment option for women with previous PPROM; however, these results require prospective validation before change in practice is recommended. Phenotype of previous preterm birth may be an important risk predictor and treatment effect modifier; this information should be reported in future clinical trials. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology