Multi-mode TES bolometer optimization for the LSPE-SWIPE instrument

In this paper we explore the possibility of using transition edge sensor (TES) detectors in multi-mode configuration in the focal plane of the Short Wavelength Instrument for the Polarization Explorer (SWIPE) of the balloon-borne polarimeter Large Scale Polarization Explorer (LSPE) for the Cosmic Microwave Background (CMB) polarization. This study is motivated by the fact that maximizing the sensitivity of TES bolometers, under the augmented background due to the multi-mode design, requires a non trivial choice of detector parameters. We evaluate the best parameter combination taking into account scanning strategy, noise constraints, saturation power and operating temperature of the cryostat during the flight.Comment: in Journal of Low Temperature Physics, 05 January 201

Corta meromixis en un lago somero de la región semiárida pampeana

Los lagos meromícticos son aquellos que no se mezclan en su totalidad debido a un fuerte gradiente salino que separa el mixolimnion (superficial, menos salino) del monimolimnion (profundo, más salino). La laguna Este de la Reserva Provincial Parque Luro (La Pampa) es una típica laguna hipersalina (salitral) que luego de una lluvia excepcional mostró una corta meromixis. El objetivo del presente trabajo fue determinar los cambios en las características físico-químicas y en las comunidades planctónicas durante la meromixis, la cual duró al menos 7 meses. En comparación con el monimolimnion, el mixolimnion se caracterizó por tener menor salinidad y nutrientes; sin embargo, tuvo mayor pH, oxígeno disuelto, clorofila, y sólidos orgánicos. La escasa profundidad de esta laguna y la acción de los vientos ocasionaron el fin de la meromixis. El fitoplancton estuvo dominado casi exclusivamente por Dunaliella salina y durante la meromixis no se observaron diferencias en la densidad o en la biomasa en su distribución vertical. El zooplancton (generalmente dominado por Artemia persimilis) redujo su riqueza con el aumento de salinidad. Mientras duró la meromixis, esta especie coexistió con Boeckella poopoensis, y ambas presentaron altas densidades de juveniles en el mixolimnion respecto del monimolimnion. El episodio de una corta meromixis, como el descripto en este estudio, permitió observar diversas condiciones limnológicas y el desarrollo de un mayor número de especies de zooplancton, algunas de ellas endémicas de la región. Estos atributos, transforman a este lago somero en un sitio de particular interés para su conservación

Estudio taxonómico preliminar de la ficoflora planctónica en la zona aluvial del Río Colorado (La Pampa, Argentina)

This work is part of a larger project on the study of algal biodiversity of a lotic system in La Pampa province. In this first stage we analyze the algal flora of samples collected during the summer season and autumn of 2010. The study area is located in the floodplain of the Colorado River, the natural boundary between the provinces of La Pampa and Río Negro at its intersection with Provincial Route 11 (Department Lihuel Calel). The methodology used in the collection followed the standard parameters for lotic environments. The samples were fixed with 4% formaldehyde and deposited in the herbarium of the Faculty of Agronomy (UNLPam) under the symbol SRFA. The preliminary results of the algal flora of summer and autumn shows 64 taxa, of which 26.5% corresponds to Cyanophyceae, 36% to Chlorophyceae and Bacillariophyceae, and 1.5% to Dinophyceae. During the summer the class Chlorophyceae species contributed 40% and fall did the Bacillariophyceae with 43.7%. The 37.5% of the registered species were common to both seasons.Instituto de Limnología "Raúl A. Ringuelet

Estudio taxonómico preliminar de la ficoflora planctónica en la zona aluvial del Río Colorado (La Pampa, Argentina)

This work is part of a larger project on the study of algal biodiversity of a lotic system in La Pampa province. In this first stage we analyze the algal flora of samples collected during the summer season and autumn of 2010. The study area is located in the floodplain of the Colorado River, the natural boundary between the provinces of La Pampa and Río Negro at its intersection with Provincial Route 11 (Department Lihuel Calel). The methodology used in the collection followed the standard parameters for lotic environments. The samples were fixed with 4% formaldehyde and deposited in the herbarium of the Faculty of Agronomy (UNLPam) under the symbol SRFA. The preliminary results of the algal flora of summer and autumn shows 64 taxa, of which 26.5% corresponds to Cyanophyceae, 36% to Chlorophyceae and Bacillariophyceae, and 1.5% to Dinophyceae. During the summer the class Chlorophyceae species contributed 40% and fall did the Bacillariophyceae with 43.7%. The 37.5% of the registered species were common to both seasons.Instituto de Limnología "Raúl A. Ringuelet

Ficoflora de la laguna Don Tomás (La Pampa, Argentina)

El objetivo del presente trabajo es analizar la composición y la distribución estacional de las especies fitoplanctónicas de la Laguna Don Tomás durante un ciclo anual. Se colectaron muestras mensuales (agosto 2002 a julio 2003), los que se estudiaron cualitativamente. Asimismo, se analizaron parámetros fisicoquímicos. Se realizó un análisis de clusters en base al índice de similitud de Sorensen, para determinar la distribución de los taxa. La riqueza específica de la taxocenosis fitoplanctónica fue de 159 taxa. Los cluster mostraron agrupamientos con una marcada distribución estacional. Se identificaron cuatro grupos. El primero compuesto por los meses de septiembre, octubre y noviembre corresponden a la primavera, el segundo grupo, verano, integrado por diciembre, enero y febrero y el tercer grupo está constituido por marzo, abril, mayo, junio y julio. Los resultados correspondientes al mes de Agosto se aíslan del resto del año por condiciones ambientales particulares.The work deals with the analyze composition and seasonal distribution of phytoplantonic species of Don Tomas Shallow lake during an annual cycle. Six monthly samples were collected (August 2002 to July 2003) and they were qualitatively studied. The physical and chemical parameters were registered in the same time. The index of similarity of Sorensen was made In order to determine the degree of similarity of the seasonal distribution of the taxa. The phytoplanctonic taxocenosis community richness specific of the was of 159 taxa. Groups with a noticeable seasonal distribution were showed with cluster analyzed. Four seasonal groups were identified. September, October and November correspond to the spring; the second group, summer, was integrated for December, January and February, and the third group was constituted for March, April, May, June and July. Different environmental conditions during the winter of 2002 had isolated the results of August.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Instituto de Limnología "Dr. Raul A. Ringuelet" (ILPLA

Ficoflora de la laguna Don Tomás (La Pampa, Argentina)

El objetivo del presente trabajo es analizar la composición y la distribución estacional de las especies fitoplanctónicas de la Laguna Don Tomás durante un ciclo anual. Se colectaron muestras mensuales (agosto 2002 a julio 2003), los que se estudiaron cualitativamente. Asimismo, se analizaron parámetros fisicoquímicos. Se realizó un análisis de clusters en base al índice de similitud de Sorensen, para determinar la distribución de los taxa. La riqueza específica de la taxocenosis fitoplanctónica fue de 159 taxa. Los cluster mostraron agrupamientos con una marcada distribución estacional. Se identificaron cuatro grupos. El primero compuesto por los meses de septiembre, octubre y noviembre corresponden a la primavera, el segundo grupo, verano, integrado por diciembre, enero y febrero y el tercer grupo está constituido por marzo, abril, mayo, junio y julio. Los resultados correspondientes al mes de Agosto se aíslan del resto del año por condiciones ambientales particulares.The work deals with the analyze composition and seasonal distribution of phytoplantonic species of Don Tomas Shallow lake during an annual cycle. Six monthly samples were collected (August 2002 to July 2003) and they were qualitatively studied. The physical and chemical parameters were registered in the same time. The index of similarity of Sorensen was made In order to determine the degree of similarity of the seasonal distribution of the taxa. The phytoplanctonic taxocenosis community richness specific of the was of 159 taxa. Groups with a noticeable seasonal distribution were showed with cluster analyzed. Four seasonal groups were identified. September, October and November correspond to the spring; the second group, summer, was integrated for December, January and February, and the third group was constituted for March, April, May, June and July. Different environmental conditions during the winter of 2002 had isolated the results of August.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Instituto de Limnología "Dr. Raul A. Ringuelet" (ILPLA

Ficoflora de la laguna Don Tomás (La Pampa, Argentina)

El objetivo del presente trabajo es analizar la composición y la distribución estacional de las especies fitoplanctónicas de la Laguna Don Tomás durante un ciclo anual. Se colectaron muestras mensuales (agosto 2002 a julio 2003), los que se estudiaron cualitativamente. Asimismo, se analizaron parámetros fisicoquímicos. Se realizó un análisis de clusters en base al índice de similitud de Sorensen, para determinar la distribución de los taxa. La riqueza específica de la taxocenosis fitoplanctónica fue de 159 taxa. Los cluster mostraron agrupamientos con una marcada distribución estacional. Se identificaron cuatro grupos. El primero compuesto por los meses de septiembre, octubre y noviembre corresponden a la primavera, el segundo grupo, verano, integrado por diciembre, enero y febrero y el tercer grupo está constituido por marzo, abril, mayo, junio y julio. Los resultados correspondientes al mes de Agosto se aíslan del resto del año por condiciones ambientales particulares.The work deals with the analyze composition and seasonal distribution of phytoplantonic species of Don Tomas Shallow lake during an annual cycle. Six monthly samples were collected (August 2002 to July 2003) and they were qualitatively studied. The physical and chemical parameters were registered in the same time. The index of similarity of Sorensen was made In order to determine the degree of similarity of the seasonal distribution of the taxa. The phytoplanctonic taxocenosis community richness specific of the was of 159 taxa. Groups with a noticeable seasonal distribution were showed with cluster analyzed. Four seasonal groups were identified. September, October and November correspond to the spring; the second group, summer, was integrated for December, January and February, and the third group was constituted for March, April, May, June and July. Different environmental conditions during the winter of 2002 had isolated the results of August.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Instituto de Limnología "Dr. Raul A. Ringuelet" (ILPLA

Variación estacional de la comunidad microfitoplanctónica del curso medio del río Colorado (La Pampa, Argentina)

We analyzed the seasonal variation of the phycoflora in the Colorado River alluvium with the aim of expanding knowledge of algal biodiversity in lotic environments of the province of La Pampa. The study area is located in the middle basin of the Colorado River (38º 49’ S and 64º 59’ W), Lihue Calel, which is the natural limit between La Pampa and Río Negro provinces. The site is located 122 meters above sea level with a channel width of 113 m. Samples were collected according to the standard methodology for lotic environments during autumn 2010 - autumn 2011. Physicochemical parameters were measured in situ. Water temperature ranged from 3.4 to 24°C for winter and summer respectively. The pH ranged between 8.1 and 8.6, the conductivity varied between 938 and 1950 μS cm-1 and the flow velocity ranged between 0.5 and 0.9 m sec-1. Phytoplankton samples were deposited in the Herbarium SRFA (UNLPam). 163 taxa were identified mostly belonging to Bacillariophyceae (42%). Chlorophyceae contributed 36%, while 17% Cyanobacteria, Euglenophyceae, Dinophyceae, Rhodophyceae and Xanthophyceae were found as companions taxa. The similarity of biodiversity in the alluvial section of the Colorado River is almost 70% as observed in the dendrogram resulting from the application of the Bray Curtis index, and grouped according to a seasonal sampling sequence.Facultad de Ciencias Naturales y Muse

Variación estacional de la comunidad microfitoplanctónica del curso medio del río Colorado (La Pampa, Argentina)

We analyzed the seasonal variation of the phycoflora in the Colorado River alluvium with the aim of expanding knowledge of algal biodiversity in lotic environments of the province of La Pampa. The study area is located in the middle basin of the Colorado River (38º 49’ S and 64º 59’ W), Lihue Calel, which is the natural limit between La Pampa and Río Negro provinces. The site is located 122 meters above sea level with a channel width of 113 m. Samples were collected according to the standard methodology for lotic environments during autumn 2010 - autumn 2011. Physicochemical parameters were measured in situ. Water temperature ranged from 3.4 to 24°C for winter and summer respectively. The pH ranged between 8.1 and 8.6, the conductivity varied between 938 and 1950 μS cm-1 and the flow velocity ranged between 0.5 and 0.9 m sec-1. Phytoplankton samples were deposited in the Herbarium SRFA (UNLPam). 163 taxa were identified mostly belonging to Bacillariophyceae (42%). Chlorophyceae contributed 36%, while 17% Cyanobacteria, Euglenophyceae, Dinophyceae, Rhodophyceae and Xanthophyceae were found as companions taxa. The similarity of biodiversity in the alluvial section of the Colorado River is almost 70% as observed in the dendrogram resulting from the application of the Bray Curtis index, and grouped according to a seasonal sampling sequence.Facultad de Ciencias Naturales y Muse

The Theory of the Interleaving Distance on Multidimensional Persistence Modules

In 2009, Chazal et al. introduced $\epsilon$-interleavings of persistence modules. $\epsilon$-interleavings induce a pseudometric $d_I$ on (isomorphism classes of) persistence modules, the interleaving distance. The definitions of $\epsilon$-interleavings and $d_I$ generalize readily to multidimensional persistence modules. In this paper, we develop the theory of multidimensional interleavings, with a view towards applications to topological data analysis. We present four main results. First, we show that on 1-D persistence modules, $d_I$ is equal to the bottleneck distance $d_B$. This result, which first appeared in an earlier preprint of this paper, has since appeared in several other places, and is now known as the isometry theorem. Second, we present a characterization of the $\epsilon$-interleaving relation on multidimensional persistence modules. This expresses transparently the sense in which two $\epsilon$-interleaved modules are algebraically similar. Third, using this characterization, we show that when we define our persistence modules over a prime field, $d_I$ satisfies a universality property. This universality result is the central result of the paper. It says that $d_I$ satisfies a stability property generalizing one which $d_B$ is known to satisfy, and that in addition, if $d$ is any other pseudometric on multidimensional persistence modules satisfying the same stability property, then $d\leq d_I$. We also show that a variant of this universality result holds for $d_B$, over arbitrary fields. Finally, we show that $d_I$ restricts to a metric on isomorphism classes of finitely presented multidimensional persistence modules.Comment: Major revision; exposition improved throughout. To appear in Foundations of Computational Mathematics. 36 page