Estudio comparado de las barreras o umbrales electorales implícitos y explícitos en el sistema electoral

"...En el presente estudio se parte, en primera instancia, de la necesaria conceptualización del término, en general y particular, y en función de ello, posteriormente, a su tipificación, sistematización y análisis especifico en Latinoamérica, mientras que ofrece un panorama general de la aplicación de las barreras electorales explicitas en diferentes regiones del mundo, para luego analizar el caso colombiano en general y visualizar el impacto de la implementación de las barreras electorales explícitas a través del acto legislativo 01 de 2003 y sus efectos en los comicios nacionales de 2006."--introducción

Protective effects of sweroside on human MG-63 cells and rat osteoblasts

Herbal Fructus Corni is a folk medicine with a long history of safe use for treating osteoporosis in postmenopausal women or elderly men in Asia. Sweroside is a bioactive herbal ingredient isolated from Fructus Corni, which has been widely used for the treatment of osteoporosis in traditional Chinese medicine (TCM). Unfortunately, the working mechanisms of this compound are difficult to determine and thus remain unclear. The aim of the study was performed to determine the potential molecular mechanism of the anti-osteoporotic effect of sweroside on the human MG-63 cells and rat osteoblasts. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used to observe the effect of sweroside on cell proliferation. The activity of alkaline phosphatase (ALP) and the amount of osteocalcin were also assayed the cell differentiation. Sweroside significantly increased the proliferation of human MG-63 cells and rat osteoblasts (P<0.01). It increased the activity of ALP, and osteocalcin was also elevated in response to sweroside (P<0.05). Of note, flowcytometer assay showed that sweroside can attenuate and inhibit apoptosis. Sweroside has a direct osteogenic effect on the proliferation and differentiation of cultured human MG-63 cells and rat osteoblasts in vitro. These data will help in understanding the molecular mechanisms of therapeutic efficacy of sweroside, and highlight insights into drug discovery. In the current study, sweroside has been suggested to be a promising osteoporosis therapeutic natural product.

The first x-ray diffraction peak of water as a function of temperature in the range 4 – 63 °C

X-ray diffraction structure functions for water flowing in a 1.5 mm diameter siphon in the temperature range 4 – 63 °C were obtained using a 20 keV beam at the Australian Synchrotron. These functions were compared with structure functions obtained at the Advanced Light Source for a 0.5 mm thick sample of water in the temperature range 1 – 77 °C irradiated with an 11 keV beam. The two sets of structure functions are similar, but there are subtle differences in the shape and relative position of the two functions suggesting a possible differences between the structure of bulk and siphon water. In addition, the first structural peak (Q0) for water in a siphon, showed evidence of a step-wise increase in Q0 with increasing temperature rather than a smoothly varying increase. More experiments are required to investigate this apparent difference.

Adolescent pedometer protocols : examining reactivity, tampering and participants' perceptions

The aim of this study was to investigate adolescents' potential reactivity and tampering while wearing pedometers by comparing different monitoring protocols to accelerometer output. The sample included adolescents (N=123, age range=14-15 years) from three secondary schools in New South Wales, Australia. Schools were randomised to one of the three pedometer monitoring protocols: (i) daily sealed (DS) pedometer group, (ii) unsealed (US) pedometer group or (iii) weekly sealed (WS) pedometer group. Participants wore pedometers (Yamax Digi-Walker CW700, Yamax Corporation, Kumamoto City, Japan) and accelerometers (Actigraph GT3X+, Pensacola, USA) simultaneously for seven days. Repeated measures analysis of variance was used to examine potential reactivity. Bivariate correlations between step counts and accelerometer output were calculated to explore potential tampering. The correlation between accelerometer output and pedometer steps/day was strongest among participants in the WS group (r=0.82, P <= 0.001), compared to the US (r=0.63, P <= 0.001) and DS (r=0.16, P=0.324) groups. The DS (P <= 0.001) and US (P=0.003), but not the WS (P=0.891), groups showed evidence of reactivity. The results suggest that reactivity and tampering does occur in adolescents and contrary to existing research, pedometer monitoring protocols may influence participant behaviour.

Effect of diabetes on amplitude of accommodation

Purpose: To determine the effect of Type 1 diabetes (DM1) on amplitude of accommodation. Method: There were 43 participants (33 ± 8 years) with DM1 and 32 (34 ± 8 years) age-balanced controls. Amplitude was measured objectively with a COAS wavefront aberrometer and subjectively with a Badal hand optometer. Results: Across both groups, objective amplitude was less than subjective amplitude by 1.4 ± 1.2 D. People with diabetes had lower objective (2.7±1.6 D) and subjective (4.0±1.7 D) amplitudes than people without diabetes (objective 4.1±2.1 D, subjective 5.6±2.1 D). For the DM1 group, the objective and subjective multivariate linear regressions were 7.1 – 0.097Age – 0.076DiabDur (R2 0.51) and 9.1 –0.103Age – 0.106DiabDur (R2 0.63), respectively. Conclusion: Objective and subjective techniques showed lowered amplitude of accommodation in DM1 participants compared with age-matched controls. Loss was affected strongly by duration of diabetes. People with diabetes will experience presbyopia earlier in life than people without diabetes.