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En 1908, Charles Nicolle y Louis Manceaux encontraron un protozoario en los tejidos de un roedor parecido a un hámster, el gundi (Ctenodactylus gundi), que se estaba utilizando para investigación en leishmaniasis en el Instituto Pasteur de Túnez, África. Simultáneamente, Splendore (1908) encontró el mismo parásito en un conejo en Brasil. Inicialmente ambos clasificaron al parásito como Leishmania spp., sin embargo, pronto se dieron cuenta de que habían descubierto un nuevo microorganismo y Nicolle y Manceaux propusieron el nombre Toxoplasma gondii (Toxoplasma mod. L. toxo = arco, plasma = vida y gondii por su hospedador inexactamente identificado). Toxoplasma gondii es el agente causal de la toxoplasmosis, enfermedad de mucha relevancia en medicina veterinaria y humana, siendo una zoonosis de alto riesgo para determinados grupos. Al día de hoy, múltiples tratamientos farmacológicos están disponibles pero ninguna vacuna desarrollada ha logrado la prevención completa de la infección y el desarrollo de la enfermedad. Debido a que T. gondii es un organismo muy fácil de manipular genéticamente, fácil de conservar y crecer en cultivo celular y con un modelo murino de hospedador-parásito bien establecido, se ha convertido en el organismo modelo más importante para el estudio de los Apicomplejos., Facultad de Ciencias Veterinarias

The Cosmology Large Angular Scale Surveyor (CLASS) is a polarization-sensitive telescope array located at an altitude of 5,200 m in the Chilean Atacama Desert. CLASS is designed to measure "E-mode" (even parity) and "B-mode" (odd parity) polarization patterns in the Cosmic Microwave Background (CMB) over large angular scales with the aim of improving our understanding of inflation, reionization, and dark matter. CLASS is currently observing with three telescopes covering four frequency bands: one at 40 GHz (Q); one at 90 GHz (W1); and one dichroic system at 150/220 GHz (G). In these proceedings, we discuss the updated design and in-lab characterization of new 90 GHz detectors. The new detectors include design changes to the transition-edge sensor (TES) bolometer architecture, which aim to improve stability and optical efficiency. We assembled and tested four new detector wafers, to replace four modules of the W1 focal plane. These detectors were installed into the W1 telescope, and will achieve first light in the austral winter of 2022. We present electrothermal parameters and bandpass measurements from in-lab dark and optical testing. From in-lab dark tests, we also measure a median NEP of 12.3 $\mathrm{aW\sqrt{s}}$ across all four wafers about the CLASS signal band, which is below the expected photon NEP of 32 $\mathrm{aW\sqrt{s}}$ from the field. We therefore expect the new detectors to be photon noise limited., 10 pages, 6 figures, to appear in Proc. SPIE Astronomical Telescopes and Instrumentation 2022

This work proposes and evaluates various improvements to a circular local path template (LPT) that we have designed in the past to estimate driver intents and to provide navigation assistance to wheelchair drivers. This LPT may also be useful in other mobile robotics applications such as for intuitive teleoperated control, for fast collision checking in path planning or for obstacle avoidance algorithms. The LPT consists of a large but fixed set of paths in the mobile robot’s local neighborhood. Based on an efficient look-up table, the LPT paths’ lengths are adjusted such that they are collisionfree. However, experiments have shown that in dense environments insufficient circular paths are found, which impedes correct intention estimation and thus navigation assistance. In this work, the use of clothoidal paths rather than circular paths is evaluated. This substantially improves the capability to find complex paths in dense areas. Furthermore, we adapt the LPT to deal with dynamic obstacles of random shape using motion prediction estimates of these objects.

El objetivo de este estudio fue determinar el comportamiento productivo en cabras Saanen mediante la caracterización de la curva de lactancia y el rendimiento de acuerdo al número de lactancia y al tipo de parto en un tambo semi-intensivo de la provincia de Buenos Aires. El hato caprino fue dividido en las diferentes categorías: cabras de primera lactancia (1°L, n=89); segunda lactancia (2°L, n=39), tercera lactancia (3°L, n=49); cuarta y quinta lactancia (4°L y 5°L, n=41) y última lactancia (UL, n=38). El tipo de parto fue clasificado en Simple (una cría, n=120) y Múltiple (dos o más crías, n=136). El control lechero se realizó evaluando el ordeño 2 veces por día cada 42 ± 4 días (método BT6) mediante ordeño mecánico con lactómetros Waikato. Mediante un análisis de varianza multifactorial, se evaluó la influencia del número de lactancia y tipo de parto sobre la lactancia completa (PLT). Se observó una diferencia estadísticamente significativa de los factores (p= 0,0074) y (p= 0,0179) respectivamente sobre la PLT. El análisis de media verificó diferencias significativas (p< 0,05) entre las cabras de 3°L y las de 1°L, 2°L y UL, así mismo, las de 4°L y 5°L respecto de UL (p< 0,05). El tipo de parto observó diferencias significativas (p< 0,05) en la PLT entre las cabras múltiples y simples. El comportamiento productivo de cabras Saanen de un establecimiento caprino semi-intensivo de la provincia de Buenos Aires, asociado al número de lactancia y el tipo de parto registraron diferencias en la producción láctea.

The current and future cosmic microwave background (CMB) experiments fielding kilo-pixel arrays of transition-edge sensor (TES) bolometers require accurate and robust gain calibration methods. We simplify and refactor the standard TES model to directly relate the detector responsivity calibration and optical time constant to the measured TES current $I$ and the applied bias current $I_{\mathrm{b}}$. The calibration method developed for the Cosmology Large Angular Scale Surveyor (CLASS) TES bolometer arrays relies on current versus voltage ($I$-$V$) measurements acquired daily prior to CMB observations. By binning Q-band (40GHz) $I$-$V$ measurements by optical loading, we find that the gain calibration median standard error within a bin is 0.3%. We test the accuracy of this "$I$-$V$ bin" detector calibration method by using the Moon as a photometric standard. The ratio of measured Moon amplitudes between detector pairs sharing the same feedhorn indicates a TES calibration error of 0.5%. We also find that for the CLASS Q-band TES array, calibrating the response of individual detectors based solely on the applied TES bias current accurately corrects TES gain variations across time but introduces a bias in the TES calibration from data counts to power units. Since the TES current bias value is set and recorded before every observation, this calibration method can always be applied to raw TES data and is not subject to $I$-$V$ data quality or processing errors., Comment: 19 pages, 7 figures, 5 tables. Submitted to ApJS May 2022. Published ApJS Oct 2022

O objetivo deste estudo foi determinar o comportamento produtivo de cabras da raça Saanen, caracterizando a curva de lactação e o rendimento de acordo com o número de lactações e o tipo de parto em uma fazenda leiteira semi-intensiva da província de Buenos Aires. O rebanho caprino foi dividido em diferentes categorias: cabras de primeira lactação (1ª L, n = 89); segunda lactação (2ª L, n = 39), terceira lactação (3ª L, n = 49); quarta e quinta lactação (4 ° L e 5 ° L, n = 41) e última lactação (UL, n = 38). O tipo de parto foi classificado em Simples (um bezerro, n = 120) e Múltiplo (dois ou mais bezerros, n = 136). O controle do leite foi realizado avaliando-se a ordenha duas vezes ao dia a cada 42 ± 4 dias (método BT6) por meio de ordenha mecânica com lactômetros Waikato. Usando uma análise de variância multifatorial, a influência do número de lactação e tipo de parto na lactação plena (PLT) foi avaliada. Houve diferença estatisticamente significativa dos fatores (p = 0,0074) e (p = 0,0179) respectivamente no PLT. A análise das médias verificou diferenças significativas (p

Toxoplasmosis is considered one of the most important causes of abortion in small ruminants. The aim of this study was to evaluate the relationship between Toxoplasma gondii antibody titres and reproductive losses over an 11 year period in a goat farm located in Buenos Aires province, Argentina. Blood samples were obtained from 85 goats, representing three breeds, during the last third of gestation (n = 165 gestations), in consecutive pregnancies (2008–2019), and from 51 goats during kidding to analyze seroconversion. Serum was evaluated by IFAT with T. gondii antigen, using 1:100 dilution as the cut-off titre and processed to end titre. An overall reproductive loss of 31% (51/165) was detected, including 16.4% (27/165) abortions and 14.6% (24/165) perinatal deaths. The seropositivity to T. gondii was 100% (85/85) with all animals positive in successive samplings and, therefore, considered chronically infected. Antibody titres showed average values greater than 1100 in each year and breed group. Differences in antibody levels were associated with breed and were lower in those that were predominately Creole and higher in those that were predominately Saanen. Seroconversion was detected in 16.2% (6/37) and 57.1% (8/14) of goats from the Creole and Sannen breed groups, respectively. There were no significant differences in the antibody titre average between goats with reproductive losses and those with healthy kids, although the goats with perinatal deaths had a significantly higher titre average. These results suggest reinfection or reactivation, although no association with reproductive losses was observed. Higher antibody titres were associated with perinatal deaths. The high T. gondii antibody titres in a farm with 100% seroprevalence did not allow for association with reproductive losses, particularly abortion, to be assessed.

Argentina es el tercer país productor de cabras de América. Se calcula que existen 5 millones cabezas. Los caprinos se distribuyen en el país principalmente en zonas áridas y semiáridas, de acuerdo a la región geográfica van a prevalecer los distintos tipos de producción (carne, leche y fibra, o mixtos). La producción de leche caprina en nuestro país fue 2 millones de litros/año. La cual se sostiene sobre la elaboración de quesos, cuya demanda se basa en sus cualidades organolépticas. En Argentina, existen alrededor de 200 tambos caprinos, con una población de aproximadamente 10.000 caprinos lecheros. En la provincia de Buenos Aires, se encuentra la Cuenca lechera de Abasto que hace años viene desarrollando fuertemente la producción láctea caprina, destinando la leche a la fabricación de quesos, debido a su cercanía de los grandes centros urbanos. Los protozoos Apicomplexa (parásitos intracelulares) de la familiaSarcocystidaese caracterizan por presentar ciclos evolutivos indirectos, produciendo quistes en tejidos de los hospedadores intermediarios y ooquistes por multiplicación sexual en el intestino de los hospedadores definitivos. Los ciclos biológicos de estas especies seasocian a cadenas tróficas del tipo predador-presa. Los caprinos son hospedadores intermediarios de diferentes especies del género Sarcocystis, Toxoplasma gondii y Neospora caninum. La toxoplasmosis y neosporosis han sido estudiadas ampliamente en caprinosde diferentes regiones del planeta, y su vinculación con pérdidas reproductivas. La sarcocystosis puede generar signos clínicos severos y abortos en pequeños rumiantes., Universidad Nacional de La Plata

Bacterial virulence factors are attractive targets for the development of therapeutics. Type IV pili, which are associated with a remarkable array of properties including motility, the interaction between bacteria and attachment to biotic and abiotic surfaces, represent particularly appealing virulence factor targets. Type IV pili are present in numerous bacterial species and are critical for their pathogenesis. In this study, we report that trifluoperazine and related phenothiazines block functions associated with Type IV pili in different bacterial pathogens, by affecting piliation within minutes. Using Neisseria meningitidis as a paradigm of Gram-negative bacterial pathogens that require Type IV pili for pathogenesis, we show that piliation is sensitive to altered activity of the Na+ pumping NADH–ubiquinone oxidoreductase (Na+−NQR) complex and that these compounds probably altered the establishment of the sodium gradient. In vivo, these compounds exert a strong protective effect. They reduce meningococcal colonization of the human vessels and prevent subsequent vascular dysfunctions, intravascular coagulation and overwhelming inflammation, the hallmarks of invasive meningococcal infections. Finally, they reduce lethality. This work provides a proof of concept that compounds with activity against bacterial Type IV pili could beneficially participate in the treatment of infections caused by Type IV pilus-expressing bacteria. Phenothiazines inhibit Type IV pili function in Neisseria meningitidis and protect against bacterial colonization of blood vessels and lethality during infection.

Bacterial virulence factors are attractive targets for the development of therapeutics. Type IV pili, which are associated with a remarkable array of properties including motility, the interaction between bacteria and attachment to biotic and abiotic surfaces, represent particularly appealing virulence factor targets. Type IV pili are present in numerous bacterial species and are critical for their pathogenesis. In this study, we report that trifluoperazine and related phenothiazines block functions associated with Type IV pili in different bacterial pathogens, by affecting piliation within minutes. Using Neisseria meningitidis as a paradigm of Gram-negative bacterial pathogens that require Type IV pili for pathogenesis, we show that piliation is sensitive to altered activity of the Na

The role of second messengers in the diversion of cellular processes by pathogens remains poorly studied despite their importance. Among these, Ca 2+ virtually regulates all known cell processes, including cytoskeletal reorganization, inflammation, or cell death pathways. Under physiological conditions, cytosolic Ca 2+ increases are transient and oscillatory, defining the so‐called Ca 2+ code that links cell responses to specific Ca 2+ oscillatory patterns. During cell invasion, Shigella induces atypical local and global Ca 2+ signals. Here, we show that by hydrolyzing phosphatidylinositol‐(4,5)bisphosphate, the Shigella type III effector IpgD dampens inositol‐(1,4,5)trisphosphate (InsP 3 ) levels. By modifying InsP 3 dynamics and diffusion, IpgD favors the elicitation of long‐lasting local Ca 2+ signals at Shigella invasion sites and converts Shigella ‐induced global oscillatory responses into erratic responses with atypical dynamics and amplitude. Furthermore, IpgD eventually inhibits InsP 3 ‐dependent responses during prolonged infection kinetics. IpgD thus acts as a pathogen regulator of the Ca 2+ code implicated in a versatility of cell functions. Consistent with this function, IpgD prevents the Ca 2+ ‐dependent activation of calpain, thereby preserving the integrity of cell adhesion structures during the early stages of infection.

El objetivo del siguiente trabajo fue evaluar el efecto del tipo de heno y nivel de concentrado sobre el pH ruminal en dietas para caprinos. Se utilizaron 4 cabras (criolla x Nubian) en un cuadrado latino de 4×4. Experimento I. 4 dietas: heno de alfalfa, heno de alfalfa + grano molido de maíz al 0,5%, 1% y 1,5% del PV/día. Experimento II. 4 dietas: heno de campo natural (CN), heno de CN + grano molido de maíz al 0,5%, 1% y 1,5% del PV/día. Se determinó el pH ruminal y se calculó el área bajo la curva, pH promedio del día, tiempo en horas con pH por debajo de 6, efecto del tiempo pos alimentación e interacción hora/tratamiento. El experimento I, verificó un incremento lineal (p< 0,05) del área bajo la curva del pH umbral y del tiempo con pH menor a 6 con el aumento de maíz en la dieta. El pH ruminal promedio del día disminuyó linealmente (p< 0,05) con el aumento del concentrado. El pH ruminal disminuyó (p< 0,05) post alimentación independiente del tratamiento, sin interacción (p< 0,05) entre hora-tratamiento. En el experimento II, se observó un efecto cúbico (p< 0,05) del área bajo la curva y el pH promedio del día, con el aumento de maíz de 0 a 1,5 % del PV. Respecto a las horas con pH por debajo de 6, no se verificaron efectos (p> 0,05). Se registraron diferencias (p< 0,05) en las horas post alimentación, sobre el pH ruminal, con interacción significativa (p< 0,05) hora-tratamiento. Se concluye que los niveles ensayados de suplementación disminuyeron el pH ruminal y el tipo de heno utilizado provocó un efecto buffer diferente en el ambiente ruminal caprino., The objective was to evaluate the effect of the level of hay and concentrate on ruminal pH in diets for goats. Four goats (Creole x Nubian) were used in a 4×4 Latin square. Experiment I. 4 diets: alfalfa hay, alfalfa hay ground grain corn + 0.5%, 1% and 1.5% LW/day. Experiment II. 4 diets: natural hay field hay natural field ground grain corn + 0.5%, 1% and 1.5% LW/day. Ruminal pH is determined and the area under the curve, the average pH of the day, time in hours with pH below 6, the effect of time after feeding and interaction time / treatment. In Experiment I, a linear increase (P 0.05) were verified. Differences (p, Facultad de Ciencias Agrarias y Forestales, Facultad de Ciencias Veterinarias

Our current view about the relationship between metals and bacteria in marine sediments might be biased because most studies only use ex situ approaches to quantify metals. The aim of the present research was to compare ex situ and in situ methods of metal measurement (DET and DGT - diffusive equilibration or diffusive gradients in thin-films) and relate the results with two commonly used microbiological variables (bacterial biomass and bacterial diversity as revealed by DGGE). No previous studies have used such in situ approaches in microbial ecology. For biomass and most of the investigated trace metals (Ag, Cd, Sn, Cr, Ni, Cu, Pb, and Al) no significant correlations were found. The exceptions were Fe, Mn, Co, and As which behave like micronutrients. For bacterial diversity, no relevant relationships were found. We conclude that in situ methods are more adapted tools for microbial ecologists but that ex situ approaches are still necessary.

The objective of this study was to investigate whether successive recruitment failures in the anchovy fishery in the Bay of Biscay were due to changes in the zooplankton biomass or composition. Image analysis and automatic recognition were used to analyse zooplankton samples collected during diel egg production method spring surveys from 1998 to 2006. We were not able to detect any trend in zooplankton biomass during this period. The zooplankton spatial distribution showed permanent features with large organisms being more abundant over the shelf break and outer areas. Finally, we found a negative correlation between anchovy recruitment and zooplankton biomass which suggests that the 2002-2006 failures in anchovy recruitment in the Bay of Biscay are not due to a decrease in mesozooplankton biomass.

In this paper, we discuss the use of micromachining techniques and silicon microfabrication technology to create miniature, low cost replacements for conventional optical spectrometers. The unique aspect of our approach is that the spectrometer is created using two separate processes involving conventional optical coating technology and surface micromachining. Sub-components of the spectrometer are then assembled to create the final device. This method provides optimum performance of the micromachined actuators and semi-transparent mirrors.