5,297 research outputs found
On Capital Market Imperfections as a Source of Low TFP and Economic Rents
We propose a theory in which capital market imperfections are at the origin of cross-country TFP differences. In our theory entrepreneurs have private information about the multifactor productivity of their technology. We study how the contracting environment, as described by the ability to enforce contracts, affects the provision of incentives and resource allocation to and across entrepreneurs. Our theory implies that countries with a low ability to enforce contracts use inefficient technologies in equilibrium and are characterized by differences in productivity across industries. These implications of our theory are supported by the empirical evidence. Our theory also suggests that entrepreneurs have a vested interest in maintaining a status quo with low enforcement since it allows them to extract rents from the factor services they hire.Capital market imperfections; Total factor productivity, Relative price distortions; Taxation.
On Capital Market Imperfections as an Origin of Low TFP and Economic Rents
We propose a theory where capital market imperfections are at the origin of cross-country TFP differences. In our theory entrepreneurs have private information about the multifactor productivity of their technology. We study how the contracting environment, as described by the ability to enforce contracts, affects the provision of incentives and, thus, resource allocation to and across entrepreneurs. We assume that countries differ in the ability to enforce contracts and show that, in the presence of assymmetric information, countries with low enforcement use inefficient technologies in equilibrium and are characterized by differences in productivity across industries. Our theory also suggests that entrepreneurs have a vested interest in maintaining a status quo with low enforcement since it allows them to extract rents from the factor services they hire.Capital Market Imperfections, Total Factor Productivity, Relative Price Distortions, Taxation
On Finance as a Theory of TFP, Cross-Industry Productivity Differences, and Economic Rents.
We develop a theory of capital-market imperfections to study how the ability to enforce contracts affects resource allocation across entrepreneurs of different productivities, and across industries with different needs for external financing. The theory implies that countries with a poor ability to enforce contracts are characterized by the use of inefficient technologies, low aggregate TFP, low development of financial markets, large differences in labor productivity across industries, and large employment shares in industries with low productivity. These implications of our theory are supported by the empirical evidence. The theory also suggests that entrepreneurs have a vested interest in maintaining a status quo with low enforcement since it allows them to extract rents from the factor services they hire.Macroeconmics, Capital Market Imperfections, Total-factor Productivity, Relative Prices, Sectorial Allocation, Limited Enforcement
Probabilistic Graphical Models on Multi-Core CPUs using Java 8
In this paper, we discuss software design issues related to the development
of parallel computational intelligence algorithms on multi-core CPUs, using the
new Java 8 functional programming features. In particular, we focus on
probabilistic graphical models (PGMs) and present the parallelisation of a
collection of algorithms that deal with inference and learning of PGMs from
data. Namely, maximum likelihood estimation, importance sampling, and greedy
search for solving combinatorial optimisation problems. Through these concrete
examples, we tackle the problem of defining efficient data structures for PGMs
and parallel processing of same-size batches of data sets using Java 8
features. We also provide straightforward techniques to code parallel
algorithms that seamlessly exploit multi-core processors. The experimental
analysis, carried out using our open source AMIDST (Analysis of MassIve Data
STreams) Java toolbox, shows the merits of the proposed solutions.Comment: Pre-print version of the paper presented in the special issue on
Computational Intelligence Software at IEEE Computational Intelligence
Magazine journa
Unrest at Domuyo Volcano, Argentina, detected by geophysical and geodetic data and morphometric analysis
New volcanic unrest has been detected in the Domuyo Volcanic Center (DVC), to the east of the Andes Southern Volcanic Zone in Argentina. To better understand this activity, we investigated new seismic monitoring data, gravimetric and magnetic campaign data, and interferometric synthetic aperture radar (InSAR) deformation maps, and we derived an image of the magma plumbing system and the likely source of the unrest episode. Seismic events recorded during 2017-2018 nucleate beneath the southwestern flank of the DVC. Ground deformation maps derived from InSAR processing of Sentinel-1 data exhibit an inflation area exceeding 300 km2, from 2014 to at least March 2018, which can be explained by an inflating sill model located 7 km deep. The Bouguer anomaly reveals a negative density contrast of ~35 km wavelength, which is spatially coincident with the InSAR pattern. Our 3D density modeling suggests a body approximately 4-6 km deep with a density contrast of -550 kg/m3. Therefore, the geophysical and geodetic data allow identification of the plumbing system that is subject to inflation at these shallow crustal depths. We compared the presence and dimensions of the inferred doming area to the drainage patterns of the area, which support long-established incremental uplift according to morphometric analysis. Future studies will allow us to investigate further whether the new unrest is hydrothermal or magmatic in origin.Fil: Astort, Ana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Walter, Thomas R. German Research Centre for Geosciences; AlemaniaFil: Ruiz, Francisco. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂsicas y Naturales. Instituto GeofĂsico SismolĂłgico Volponi; ArgentinaFil: Sagripanti, LucĂa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Nacif, Andres Antonio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂsicas y Naturales. Instituto GeofĂsico SismolĂłgico Volponi; ArgentinaFil: Acosta, Gemma. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂsicas y Naturales. Instituto GeofĂsico SismolĂłgico Volponi; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Folguera Telichevsky, Andres. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentin
Locations of several novel 2'-O-methylated nucleotides in human 28S rRNA
BACKGROUND: Ribose 2'-O-methylation, the most common nucleotide modification in mammalian rRNA, is directed by the C/D box small nucleolar RNAs (snoRNAs). Thus far, more than fifty putative human rRNA methylation guide snoRNAs have been identified. For nine of these snoRNAs, the respective ribose methylations in human 28S rRNA have been only presumptive. RESULTS: In this study, the methylation state of human 28S rRNA in the positions predicted by the snoRNAs U21, U26, U31, U48, U50, U73, U74, U80 and U81 was assessed using reverse transcription-based methods and several novel 2'-O-methylations were localized. CONCLUSIONS: Seven novel ribose 2'-O-methylated residues (Am389, Am391, Gm1604, Gm1739, Gm2853, Cm3810, Gm4156, predicted by snoRNAs U26, U81, U80, U73, U50, U74 and U31, respectively) have been localized in human 28S rRNA. The total number of 2'-O-methylations in human rRNA is not yet known
Structure and composition of dung-beetles communities (Scarabaeidae: Scarabaeinae) in diferentes cattle systems of atlantic forest in Argentina
Se realizĂł un inventario de la diversidad taxonĂłmica de las comunidades de escarabajosestercoleros en sistemas ganaderos, bajo tres modalidades en el bosque AtlĂĄntico de Argentina: 1)parquizados, ganaderĂa en bosque nativo, 2) silvopastoriles, ganaderĂa en plantaciones de pino, 3)potreros, ganaderĂa en pastizales abiertos. Se registraron un total de 759 individuos correspondientes a29 especies/morfo-especies. Canthon quinquemaculatus fue la especie mĂĄs abundante de todo elmuestreo. En los sistemas de parquizados se colectaron el 71% del total de los individuos (n=541),mientras que en los potreros se colecto apenas el 6% (n=43). Los parquizados son los usos de la tierraque mejor conservan la fauna nativa de estercoleros en comparaciĂłn con los sistemas silvopastoriles ypotreros.We performed a taxonomical inventory of dung beetles diversity on three different
cattle systems in the Atlantic forest of Argentina: 1) âparquizadosâ, cattle systems in native forest, 2) silvopastoral, cattle systems in pine plantations, 3) pastures, cattle systems in open grazing. We selected five replicates of each cattle system and five more for native forest. A total of 759 individuals were collected, from 29 species/morpho-species. Canthon quinquemaculatus was the most abundant species in all habitats. The large majority of individuals were collected in âParquizadosâ(71%), while only 6% were collected in pastures (n=43). âParquizadosâ were the land uses that better preserves the native fauna compare to silvopastoral and pastures systems.Fil: Gomez Cifuentes, Andres Mauricio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Nordeste. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș | Universidad Nacional de Misiones. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș; ArgentinaFil: Gimenez Gomez, Victoria Carolina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Nordeste. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș | Universidad Nacional de Misiones. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș; ArgentinaFil: Munevar Lozano, Ana Katerinne. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Nordeste. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș | Universidad Nacional de Misiones. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș; ArgentinaFil: Zurita, Gustavo Andres. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Nordeste. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș | Universidad Nacional de Misiones. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Puerto IguazĂș; Argentin
NOTAS SOBRE LA ANIDACIĂN DEL BIENPARADO COMĂN (NYCTIBIUS GRISEUS) EN EL VALLE GEOGRĂFICO DEL RIO CAUCA (CALI, COLOMBIA)
RESUMEN â El Bienparado ComĂșn (Nyctibius griseus) habita desde el oeste de MĂ©xico hasta el norte de Argentina y Uruguay. A pesar de ser una especie comĂșn, la informaciĂłn existente sobre su historia natural es muy poca, especialmente sobre su comportamiento reproductivo. En este trabajo proveemos informaciĂłn detallada sobre su biologĂa reproductiva basada en cuatro nidos monitoreados en Cali (Valle geogrĂĄfico del Rio Cauca, Colombia). Los nidos eran concavidades en la parte superior de ramas truncadas, en cada una de las cuales se encontrĂł un huevo blanco con manchas lila y marrĂłn claro, distribuidas en toda la superficie. Durante la incubaciĂłn, los padres permanecieron en el nido todo el dĂa hasta las 18:34 ± 00:06 h (rango = 18:24â18:53 h), momento en el cual los adultos dejan desatendido el nido hasta el inicio de la sesiĂłn de incubaciĂłn nocturna, la cual empezĂł a las 19:08 ± 00:07 h (rango = 19:00â19:15 h). El porcentaje de atenciĂłn al nido fue de 95,03 ± 0,98% (n = 1 nido). El tiempo de permanencia del polluelo en el nido fue 46 dĂas (n = 1 nido), con una tasa especĂfica de crecimiento (K) de 0,124. La forma del nido, coloraciĂłn del huevo y cuidado parental registrados aquĂ concuerdan con reportes previos para esta y otras especies del gĂ©nero. Sin embargo, la atenciĂłn al nido y la tasa de crecimiento de los polluelos fueron mayores que la registrada en otros estudios.ABSTRACT â Notes on the nesting of Common Potoo (Nyctibius griseus) in the valley of Rio Cauca (Cali, Colombia) Thee Common Potoo (N. griseus) is distributed from west Mexico to northern Argentina and Uruguay. Despite its wide distribution, information regarding its natural history is sparse, in particular concerning its nesting behavior. In this study, we present detailed breeding biology information based on four nests monitored in Cali, Colombia (RĂo Cauca valley). Nests were concavities on the top of truncated branches where one white egg with lilac and light brown speckles distributed over the entire surface was laid. Based on nest temperature loggers the parents incubated continuously through the day. The first foraging trip in the evening at 18:34 ± 00:06 h (range = 18:24â18:53 h) interrupted incubation until the start of the nocturnal incubation shift at 19:08 ± 00:07 h (range = 19:00â19:15 h). Nest attentiveness was 95.03 ± 0.98% (n = 1 nest). The nestling period lasted 46 days (n = 1 nest), and nestling growth rate (K) was 0.124. Nest shape, egg coloration, and parental care recorded in our study were consistent with previous reports for N. griseus and other species of the genus. However, nest attentiveness and growth rate of nestlings were higher compared with other studies
A portable and affordable aligner for the assembly of microfluidic devices
The incorporation of sophisticated capabilities within microfluidic devices often requires the assembly of different layers in a correct arrangement. For example, when it is desired to include electrodes inside microfluidic channels or to create 3D microfluidic structures. However, the alignment between different substrates at the microscale requires expensive equipment not available for all research groups. In this work, we present an affordable, compact and portable aligner for assembling multilayered composite microfluidic chips. The instrument is composed of aluminum machined pieces combined with precision stages and includes a digital microscope with a LED illumination system for monitoring the alignment process. An interchangeable holder was created for substrate fixing, allowing the bonding of PDMS with other materials. Microscopic visualization is achieved through any device with internet access, avoiding the need of a computer attached to the aligner. To test the performance of the aligner, the center of an indium tin oxide microelectrode on a glass substrate was aligned with the center of a microchannel in a PDMS chip. The accuracy and precision of the instrument are suited for many microfluidic applications. The small and inexpensive design of the aligner makes it a cost-effective option for small groups working in microfluidics.Fil: Guglielmotti, Victoria. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Saffioti, Nicolas Andres. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: TohmĂ©, Ana Laura. Universidad Nacional de San Martin. Instituto de Nanosistemas; ArgentinaFil: Gambarotta, MartĂn. Universidad Nacional de San Martin. Instituto de Nanosistemas; ArgentinaFil: Corthey, GastĂłn. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Pallarola, Diego Andres. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Global analysis of the sugarcane microtranscriptome reveals a unique composition of small RNAs associated with axillary bud outgrowth
Axillary bud outgrowth determines shoot architecture and is under the control of endogenous hormones and a fine-tuned gene-expression network, which probably includes small RNAs (sRNAs). Although it is well known that sRNAs act broadly in plant development, our understanding about their roles in vegetative bud outgrowth remains limited. Moreover, the expression profiles of microRNAs (miRNAs) and their targets within axillary buds are largely unknown. Here, we employed sRNA next-generation sequencing as well as computational and gene-expression analysis to identify and quantify sRNAs and their targets in vegetative axillary buds of the biofuel crop sugarcane (Saccharum spp.). Computational analysis allowed the identification of 26 conserved miRNA families and two putative novel miRNAs, as well as a number of trans-acting small interfering RNAs. sRNAs associated with transposable elements and protein-encoding genes were similarly represented in both inactive and developing bud libraries. Conversely, sequencing and quantitative reverse transcription-PCR results revealed that specific miRNAs were differentially expressed in developing buds, and some correlated negatively with the expression of their targets at specific stages of axillary bud development. For instance, the expression patterns of miR159 and its target GAMYB suggested that they may play roles in regulating abscisic acid-signalling pathways during sugarcane bud outgrowth. Our work reveals, for the first time, differences in the composition and expression profiles of diverse sRNAs and targets between inactive and developing vegetative buds that, together with the endogenous balance of specific hormones, may be important in regulating axillary bud outgrowth
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