FinanciaL Stability, Monetary Policy and Central Banking: an Overview

This overview presents an integrated summary of the works presented at the twelfth annual conference of the Central Bank of Chile, Financial Stability, Monetary Policy and Central Banking,” held in November 2008 and to be compiled into a forthcoming book. The works, that include both theoretical and empirical aspects, contribute elements for financial stability management within the context of global financial integration.

Financial Stability, Monetary Policy and Central Banking: An Overview

This paper summarizes the works presented at the twelfth Annual Conference at the Central Bank of Chile entitled “Financial Stability, Monetary Policy and Central Banking”, held in November 2008 and compiled in a forthcoming book. These works, that include both theoretical and empirical aspects, provide elements to handle financial stability in a globally integrated financial context.

Curiosity driven search: When is relevance irrelevant?

Classical information search behaviour models based on work-task scenarios fail to explain common leisure search scenarios motivated by a hedonistic need rather than a defined information need. This paper presents work into such unstructured search driven by curiosity. In order to explore this hedonistic catalyst, a social media search application was designed in which the search experience is triggered by the user's spatio-temporal context during their exploration rather than query-response based information retrieval. We report a study with real users and a simulated casual-leisure search task where results indicated that relevance is not relevant for some searches

Cultivo y crecimiento de dos especies de diatomeas bentónicas aisladas del Salar del Huasco (Norte de Chile, 20° S) a diferentes condiciones de temperatura, luz y nutrientes

Benthic diatoms are cultured usually under laboratory conditions to be used as a food source for other organisms, ofaquaculture interest or for biotechnological applications. Laboratory experiments demonstrate the incidence of the physicaland chemical variables on abundance and growth rates of diatoms. While macronutrients are usually selected and dosed intocommon culture mediums to meet the general requirements of a wide range of diatoms, the availability and optimizationof micronutrients are more susceptible to each organism’s particular physiological conditions. The aim of this study was tocharacterize the growth of two species of benthic diatoms isolated from the Salar de Huasco in batch cultures at differentconditions of temperature (10, 15 and 20 °C), light intensity (40, 80 and 120 ?mol m-2 s-1) and concentrations of silica (1.06x 10-4 M Na2SiO3 x 9H2O and 2.12 x 10-4 M Na2SiO3 x 9H2O) and selenium (10-8 M H2SeO3) in f/2 medium, on a lightdarkcycle of 18:6 h. Both Nitzschia epithemioides Grunow in Cleve & Grunow (1880) as Nitzschia sp. showed highermaximum cell densities (692800 ± 107704 and 649600 ± 68942 cells ml-1, respectively) and exponential growth rates(1.80±0.56 and 0.97±0.32 div. d-1, respectively) at the highest temperature (20°C). The light intensity to which the cultureswere exposed had no effect on cell density and exponential growth rate in both taxa. Regarding to nutrients, an increasein silicates concentrations on the culture medium could promote the growth of N. epithemioides and Nitzschia sp. since atendency was observed to higher cell densities (1.08 x 106 ± 84,639 and 1.32 x 106 ± 109,038 cells ml-1, respectively) andexponential growth rates (1.98 ± 0.44 and 0.95 ± 0.18 div. d-1, respectively) with respect at the normal f/2 medium and f/2medium plus selenium. Simultaneous addition of silicate and selenium to the culture medium increased the maximum celldensity of the two strains under study, but this increase was significant (p = 0.05) only for N. epithemioides and amongthe normal f/2 medium (719200 ± 116895 cells ml-1) and the f/2 medium with double the amount of silicate and selenium(1498800 ± 209599 cells ml-1). However, the exponential growth rates were not significantly different when comparedto those of the control (without the addition of silicate and selenium). In conclusion both N. epithemioides and Nitzschiasp shown an increased cell density and exponential growth rate at 20 °C. The different light intensities not significantlyinfluenced the growth of both taxa. An increase in the concentration of silicates or simultaneous increase in silicatesand selenium in the culture medium can be considered as possible strategy to increase cell density of benthic diatom N.epithemioides in batch cultures.de alimento de otros organismos de interés acuícola o para aplicaciones biotecnológicas. Experimentos de laboratoriodemuestran la incidencia de las variables físicas y químicas sobre la abundancia y tasas de crecimiento de las diatomeas.Mientras los macronutrientes están generalmente seleccionados y dosificados en los medios de cultivo más comunespara satisfacer los requerimientos generales de un amplio rango de diatomeas, la disponibilidad y optimización demicronutrientes son más susceptibles a las condiciones fisiológicas particulares de cada organismo. El objetivo de esteestudio fue caracterizar el crecimiento de dos especies de diatomeas bentónicas aisladas del Salar de Huasco en cultivostipo batch, a diferentes condiciones de temperatura (10, 15 y 20 °C), intensidad de la luz (40, 80 y 120 ?mol m-2 s-1), y concentraciones de sílice (1.06 x 10-4 M Na2SiO3 x 9H2O y 2.12 x 10-4 M Na2SiO3 x 9H2O) y selenio (10-8 M H2SeO3)en medio f/2, a un ciclo 18:6 h luz-oscuridad. Tanto Nitzschia epithemioides Grunow in Cleve & Grunow (1880) comoNitzschia sp, exhibieron las mayores densidades celulares máximas (692800 ± 107704 y 649600 ± 68942 células mL-1,respectivamente) y tasas de crecimiento exponencial (1,80 ± 0,56 y 0,97 ± 0,32 div. d-1, respectivamente) a la temperaturamás elevada (20 °C). La intensidad de luz a la cual los cultivos fueron expuestos no afectó la densidad celular y tasa decrecimiento exponencial en ambos taxa. En cuanto a los nutrientes, un incremento en la concentración de silicatos en elmedio de cultivo, podría favorecer el crecimiento de N. epithemioides y Nitzschia sp. ya que se observó una tendenciaal aumento en la densidad celular (1,08 x 106 ± 84.639 y 1,32 x 106 ± 109.038 células mL-1, respectivamente) y tasa decrecimiento exponencial (1,98 ± 0,44 y 0,95 ± 0,18 div. d-1, respectivamente) con respecto a los medios f/2 normal y f/2más selenio. La adición simultanea de silicato y selenio al medio de cultivo aumentó las densidades celulares máximas delas dos cepas bajo estudio, pero este aumento fue significativo (p = 0,05) sólo para N. epithemioides y entre los medios decultivo f/2 normal (719200 ± 116895 células mL?1) y medio f/2 con el doble de silicato y selenio (1498800 ± 209599 célulasmL-1). Sin embargo, las tasas de crecimiento exponencial no tuvieron diferencias significativas con el control (sin adiciónde silicato y selenio). En conclusión tanto N. epithemioides y Nitzschia sp. muestran un aumento en la densidad celular yla tasa de crecimiento exponencial a 20 °C. Las diferentes intensidades de luz evaluadas no influyeron significativamenteen el crecimiento de ambos taxa. Un aumento en la concentración de silicatos o aumento simultáneo de silicatos y selenioen el medio de cultivo puede ser considerado como posible estrategia para incrementar la densidad celular de la diatomeabentónica N. epithemioides en cultivos discontinuos

Affordable passive 3D-printed prosthesis for persons with partial hand amputation

Background and Aim: Partial hand amputations are common in developing countries and have a negative impact on patients and their families’ quality of life. The uniqueness of each partial hand amputation, coupled with the relatively high costs of prostheses, makes it challenging to provide suitable prosthetic solutions in developing countries. Current solutions often have long lead times and require a high level of expertise to produce. The aim of this study was to design and develop an affordable patient-specific partial hand prosthesis for developing countries. Technique: The prosthesis was designed for a patient with transmetacarpal amputation (i.e. three amputated fingers and partial palm). The final design was passive, controlled by the contralateral hand, and utilized the advanced flexibility properties of thermoplastic polyurethane in a glove-like design that costs approximately 20 USD to fabricate. Quantitative and qualitative tests were conducted to assess performance of the device after the patient used the final design. A qualitative assessment was performed to gather the patient’s feedback following a series of tests of grasp taxonomy. A quantitative assessment was performed through a grasp and lift test to measure the prosthesis’ maximum load capacity. Discussion: This study showed that the prosthesis enhanced the patient’s manual handling capabilities, mainly in the form of grasp stability. The prosthesis was light weight and could be donned and doffed by the patient independently. Limitations include the need to use the contralateral hand to achieve grasping and low grasp strength. Clinical relevance: Persons with partial hand amputation in developing countries lack access to affordable functional prostheses, hindering their ability to participate in the community. 3D-printed prostheses can provide a low-cost solution that is adaptable to different amputation configurations

Cytomolecular identification of individual wheat-wheat chromosome arm associations in wheat-rye hybrids

Chromosome pairing in the meiotic metaphase I of wheatrye hybrids has been characterized by sequential genomic and fluorescent in situ hybridization allowing not only the discrimination of wheat and rye chromosomes, but also the identification of the individual wheat and rye chromosome arms involved in the chromosome associations. The majority of associations (93.8%) were observed between the wheat chromosomes. The largest number of wheat-wheat chromosome associations (53%) was detected between the A and D genomes, while the frequency of B-D and A-B associations was significantly lower (32 and 8%, respectively). Among the A-D chromosome associations, pairing between the 3AL and 3DL arms was observed with the highest frequency, while the most frequent of all the chromosome associations (0.113/ cell) was found to be the 3DS-3BS. Differences in the pairing frequency of the individual chromosome arms of wheat-rye hybrids have been discussed in relation to the homoeologous relationships between the constituent genomes of hexaploid wheat

A numerical study of two different specimen fixtures for the modified compact tension test – their influence on concrete fracture parameters

The modified compact tension test (MCT) may represent a new test configuration for the performance of static and other kinds of fatigue tests on concrete-like materials. Core drilling can be employed to obtain specimens which are cylindrical in shape and have a standard diameter of 150 mm, this being appropriate for the determination of the residual life of structures. This contribution focuses on the evaluation of MCT specimen fracture behavior during static tests. Cracks evolution are simulated numerically using ATENA finite element (FE) software, while the results are represented as L-COD diagrams, i.e. load vs. crack opening displacement measured on the loading axis. After numerical calculations, the results for two different fixtures are compared and the advantages or drawbacks for each solution are discussed

Morphological characteristics of motor neurons do not determine their relative susceptibility to degeneration in a mouse model of severe spinal muscular atrophy

Spinal muscular atrophy (SMA) is a leading genetic cause of infant mortality, resulting primarily from the degeneration and loss of lower motor neurons. Studies using mouse models of SMA have revealed widespread heterogeneity in the susceptibility of individual motor neurons to neurodegeneration, but the underlying reasons remain unclear. Data from related motor neuron diseases, such as amyotrophic lateral sclerosis (ALS), suggest that morphological properties of motor neurons may regulate susceptibility: in ALS larger motor units innervating fast-twitch muscles degenerate first. We therefore set out to determine whether intrinsic morphological characteristics of motor neurons influenced their relative vulnerability to SMA. Motor neuron vulnerability was mapped across 10 muscle groups in SMA mice. Neither the position of the muscle in the body, nor the fibre type of the muscle innervated, influenced susceptibility. Morphological properties of vulnerable and disease-resistant motor neurons were then determined from single motor units reconstructed in Thy.1-YFP-H mice. None of the parameters we investigated in healthy young adult mice - including motor unit size, motor unit arbor length, branching patterns, motor endplate size, developmental pruning and numbers of terminal Schwann cells at neuromuscular junctions - correlated with vulnerability. We conclude that morphological characteristics of motor neurons are not a major determinant of disease-susceptibility in SMA, in stark contrast to related forms of motor neuron disease such as ALS. This suggests that subtle molecular differences between motor neurons, or extrinsic factors arising from other cell types, are more likely to determine relative susceptibility in SMA