88 research outputs found
Repensando la relación entre los cambios sociales y los cambios legales en el buenos aires del siglo XIX
Este estudio examina las conexiones entre conflictos familiares encontrados en los tribunales de Buenos Aires del siglo XIX y el mundo de la jurisprudencia. Aunque muchas leyes coloniales seguían vigentes después de la independencia, las actitudes de muchos jueces, abogados y políticos hacia esas leyes cambiaron, lo cual trajo un cambio en la interpretación y aplicación de las leyes viejas que afectó la vida diaria de porteños durante la transición entre la colonia y la nación
Membrane Process for Biological Treatment of Contaminated Gas Streams
A Hollow Fiber Membrane Bioreactor Was Investigated for Control of Air Emissions of Biodegradable Volatile Organic Compounds (VOCs). in the Membrane Bioreactor, Gases Containing VOCs Pass through the Lumen of Microporous Hydrophobic Hollow Fiber Membranes. Soluble Compounds Diffuse through the Membrane Pores and Partition into a VOC Degrading Biofilm. the Hollow Fiber Membranes Serve as a Support for the Microbial Population and Provide a Large Surface Area for VOC and Oxygen Mass Transfer. Experiments Were Performed to Investigate the Effects of Toluene Loading Rate, Gas Residence Time, and Liquid Phase Turbulence on Toluene Removal in a Laboratory-Scale Membrane Bioreactor. Initial Acclimation of the Microbial Culture to Toluene Occurred over a Period of Nine Days, after Which a 70% Removal Efficiency Was Achieved at an Inlet Toluene Concentration of 200 Ppm and a Gas Residence Time of 1.8 S (Elimination Capacity of 20 G M-3 Min-1). at Higher Toluene Loading Rates, a Maximum Elimination Capacity of 42 G M-3 Min-1 Was Observed. in the Absence of a Biofilm (Abiotic Operation), Mass Transfer Rates Were Found to Increase with Increasing Liquid Recirculation Rates. Abiotic Mass Transfer Coefficients Could Be Estimated using a Correlation of Dimensionless Parameters Developed for Heat Transfer. Liquid Phase Recirculation Rate Had No Effect on Toluene Removal When the Biofilm Was Present, However. Three Models of the Reactor Were Created: A Numeric Model, a First-Order Flat Sheet Model, and a Zero-Order Flat Sheet Model. Only the Numeric Model Fit the Data Well, Although Removal Predicted as a Function of Gas Residence Time Disagreed Slightly with that Observed. a Modification in the Model to Account for Membrane Phase Resistance Resulted in an Underprediction of Removal. Sensitivity Analysis of the Numeric Model Indicated that Removal Was a Strong Function of the Liquid Phase Biomass Density and Biofilm Diffusion Coefficient, with Diffusion Rates Below 10-9 M2 S-1 Resulting in Decreased Removal Rates
American Piano Quartet
A performance by the American Piano Quartet.https://digitalcommons.usu.edu/music_programs/1217/thumbnail.jp
Development of scalable manufacturing process and GMP-compatible formulation for a novel recombinant schistosomiasis vaccine
Schistosomiasis is a parasitic disease spread by fresh water snails. After malaria, schistosomiasis is the deadliest parasitic disease, plaguing an estimated 200 million people worldwide, and causing up to 280,000 fatalities in Africa. This neglected tropical disease has also emerged as an important co-factor in Africa’s HIV/AIDS epidemic, especially among women and adolescent girls. Together with hookworm disease and leishmaniasis, it ranks as the neglected tropical disease with the highest disease burden as defined by disability-adjusted life years (DALYs)1. Although treatments exist, such as praziquantel chemotherapy, a vaccine will likely be needed to prevent infection and re-infection, interrupt disease transmission, and ultimately establish long-term control and elimination of the disease. No such vaccine currently exists, but a promising candidate is currently under development at Texas Children’s Hospital Center for Vaccine Development (TCH-CVD).
The Sm-TSP-2 schistosomiasis vaccine comprises a 9 kDa recombinant protein corresponding to the extracellular domain of a unique S. mansoni tetraspanin found in the parasite’s tegumental surface. Sm-TSP-2 was expressed as a recombinant protein secreted by the yeast PichiaPinkTM and purified in a two-step process, which resulted in a protein recovery yield of 31% and a protein purity of 97%.2 The developed processes were suitable for production of purified protein for subsequent formulation and Phase 1 clinical studies. However, improvements in process yield and efficiency, as well as transition of the formulation to GMP-compatible materials, are desirable for the advancement of this candidate through subsequent clinical phases and large-scale manufacturing.
TCH-CVD and MilliporeSigma are conducting a collaborative project to optimize the efficiency and scalability of the Sm-STP-2 schistosomiasis vaccine manufacturing process. The overall goal of this work is to develop a safe and low-cost process for the purification of the vaccine antigen. This was accomplished by redesigning the original process, which utilized 750kD hollow fiber and 3kD cellulose membrane tangential flow filtration (TFF) devices for the clarification and concentration of the Pichia pastoris-based vaccine lysate process feed. The level of solids in the fermentation broth (30%) had required a dilution to enable processing through the hollow fiber device, which led to decreased product yield and increased complexity.
MilliporeSigma assisted TCH-CVD with studies to eliminate the dilution prior to lysate clarification and to also streamline the process to enable Texas Children’s to simultaneously clarify and concentrate the yeast lysate. 0.1um, open-channel, stacked plate, membrane sheet TFF devices were successfully used to clarify the undiluted lysate. The TFF operating parameters (specifically the feed and permeate flow rates) were optimized to enable the downstream 3kD concentration process to run concurrently in a cascade TFF. Enhancement of the chromatography operations is currently underway as well. This presentation will detail the optimized clarification and concentration process and highlight the economic and process simplification benefits.
Work was also performed to optimize the vaccine formulation. Extensive studies were previously conducted to identify excipients and conditions to maximize the stability of soluble recombinant Sm-TSP-2.3 Additional components were tested to find alternative GMP-grade reagents that maintained or improved the stability of the vaccine.
REFRENCES
1. Forgotten People, Forgotten Diseases: The Neglected Tropical Diseases and Their Impact on Global Health and Development, Second Edition. Peter J. Hotez. American Society for Microbiology Press, Washington, DC, USA, 2013.
2. Curti E et al. Hum Vaccin Immunother. 2013 Nov;9(11):2342-50.
3. Cheng W et al. Hum Vaccin Immunother. 2013 Nov;9(11):2351-61
Measure representation and multifractal analysis of complete genomes
This paper introduces the notion of measure representation of DNA sequences.
Spectral analysis and multifractal analysis are then performed on the measure
representations of a large number of complete genomes. The main aim of this
paper is to discuss the multifractal property of the measure representation and
the classification of bacteria. From the measure representations and the values
of the spectra and related curves, it is concluded that these
complete genomes are not random sequences. In fact, spectral analyses performed
indicate that these measure representations considered as time series, exhibit
strong long-range correlation. For substrings with length K=8, the
spectra of all organisms studied are multifractal-like and sufficiently smooth
for the curves to be meaningful. The curves of all bacteria
resemble a classical phase transition at a critical point. But the 'analogous'
phase transitions of chromosomes of non-bacteria organisms are different. Apart
from Chromosome 1 of {\it C. elegans}, they exhibit the shape of double-peaked
specific heat function.Comment: 12 pages with 9 figures and 1 tabl
Executive Function and Falls in Older Adults: New Findings from a Five-Year Prospective Study Link Fall Risk to Cognition
Background: Recent findings suggest that executive function (EF) plays a critical role in the regulation of gait in older adults, especially under complex and challenging conditions, and that EF deficits may, therefore, contribute to fall risk. The objective of this study was to evaluate if reduced EF is a risk factor for future falls over the course of 5 years of follow-up. Secondary objectives were to assess whether single and dual task walking abilities, an alternative window into EF, were associated with fall risk. Methodology/Main Results We longitudinally followed 256 community-living older adults (age: 76.4±4.5 yrs; 61% women) who were dementia free and had good mobility upon entrance into the study. At baseline, a computerized cognitive battery generated an index of EF, attention, a closely related construct, and other cognitive domains. Gait was assessed during single and dual task conditions. Falls data were collected prospectively using monthly calendars. Negative binomial regression quantified risk ratios (RR). After adjusting for age, gender and the number of falls in the year prior to the study, only the EF index (RR: .85; CI: .74–.98, p = .021), the attention index (RR: .84; CI: .75–.94, p = .002) and dual tasking gait variability (RR: 1.11; CI: 1.01–1.23; p = .027) were associated with future fall risk. Other cognitive function measures were not related to falls. Survival analyses indicated that subjects with the lowest EF scores were more likely to fall sooner and more likely to experience multiple falls during the 66 months of follow-up (p<0.02). Conclusions/Significance: These findings demonstrate that among community-living older adults, the risk of future falls was predicted by performance on EF and attention tests conducted 5 years earlier. The present results link falls among older adults to cognition, indicating that screening EF will likely enhance fall risk assessment, and that treatment of EF may reduce fall risk
Comparison of balance assessment modalities in emergency department elders: a pilot cross-sectional observational study
<p>Abstract</p> <p>Background</p> <p>More than one-third of US adults 65 and over fall every year. These falls may cause serious injury including substantial long-term morbidity (due declines in activities of daily living) and death. The emergency department (ED) visit represents an opportunity for identifying high risk elders and potentially instituting falls-related interventions. The unique characteristic of the ED environment and patient population necessitate that risk-assessment modalities be validated in this specific setting. In order to better identify elders at risk of falls, we examined the relationship between patient-provided history of falling and two testing modalities (a balance plate system and the timed up-and-go [TUG] test) in elder emergency department (ED) patients.</p> <p>Methods</p> <p>We conducted a cross-sectional observational study of patients ≥ 60 years old being discharged from the ED. Patient history of falls in the past week, month, 6 months, and year was obtained. Balance plate center of pressure excursion (COP) measurements and TUG testing times were recorded. COP was recorded under four conditions: normal stability eyes open (NSEO) and closed (NSEC), and perturbed stability eyes open and closed. Correlation between TUG and COP scores was measured. Univariate logistic regression was used to identify the relationship between patient-provided falls history and the two testing modalities. Proportions, likelihood ratios, and receiver-operating-characteristic (ROC) curves for prediction of previous falls were reported.</p> <p>Results</p> <p>Fifty-three subjects were enrolled, 11% had fallen in the previous week and 42% in the previous year. There was no correlation between TUG and any balance plate measurements. In logistic regression, neither testing modality was associated with prior history of falls (<it>p </it>> 0.05 for all time periods). Balance plate NSEO and NSEC testing cutoffs could be identified which were 83% sensitive and had a negative likelihood ratio (LR-) of 0.3 for falls in the past week. TUG testing was not useful for falls in the past week, but performed best for more distant falls in the past month, 6 months, or year. TUG cutoffs with sensitivity over 80% and LR(-) of 0.17-0.32 could be identified for these time periods.</p> <p>Conclusion</p> <p>Over 40% of community-dwelling elder ED patients report a fall within the past year. Balance plate and TUG testing were feasibly conducted in an ED setting. There is no relationship between scores on balance plate and TUG testing in these patients. In regression analysis, neither modality was significantly associated with patient provided history of falls. These modalities should not be adopted for screening purposes in elders in the ED setting without validation in future studies or as part of multi-factorial risk assessment.</p
Qualitative exploration of why people repeatedly attend emergency departments for alcohol-related reasons
Climate change, precipitation and impacts on an estuarine refuge from disease
© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 6 (2011): e18849, doi:10.1371/journal.pone.0018849.Oysters play important roles in estuarine ecosystems but have suffered recently due to overfishing, pollution, and habitat loss. A tradeoff between growth rate and disease prevalence as a function of salinity makes the estuarine salinity transition of special concern for oyster survival and restoration. Estuarine salinity varies with discharge, so increases or decreases in precipitation with climate change may shift regions of low salinity and disease refuge away from optimal oyster bottom habitat, negatively impacting reproduction and survival. Temperature is an additional factor for oyster survival, and recent temperature increases have increased vulnerability to disease in higher salinity regions. We examined growth, reproduction, and survival of oysters in the New York Harbor-Hudson River region, focusing on a low-salinity refuge in the estuary. Observations were during two years when rainfall was above average and comparable to projected future increases in precipitation in the region and a past period of about 15 years with high precipitation. We found a clear tradeoff between oyster growth and vulnerability to disease. Oysters survived well when exposed to intermediate salinities during two summers (2008, 2010) with moderate discharge conditions. However, increased precipitation and discharge in 2009 reduced salinities in the region with suitable benthic habitat, greatly increasing oyster mortality. To evaluate the estuarine conditions over longer periods, we applied a numerical model of the Hudson to simulate salinities over the past century. Model results suggest that much of the region with suitable benthic habitat that historically had been a low salinity refuge region may be vulnerable to higher mortality under projected increases in precipitation and discharge. Predicted increases in precipitation in the northeastern United States due to climate change may lower salinities past important thresholds for oyster survival in estuarine regions with appropriate substrate, potentially disrupting metapopulation dynamics and impeding oyster restoration efforts, especially in the Hudson estuary where a large basin constitutes an excellent refuge from disease.Funding was provided by the Hudson River Foundation, grant number 00607A, and the New York State Department of Environmental Conservation (MOU 2008)
Balancing with Vibration: A Prelude for “Drift and Act” Balance Control
Stick balancing at the fingertip is a powerful paradigm for the study of the control of human balance. Here we show that the mean stick balancing time is increased by about two-fold when a subject stands on a vibrating platform that produces vertical vibrations at the fingertip (0.001 m, 15–50 Hz). High speed motion capture measurements in three dimensions demonstrate that vibration does not shorten the neural latency for stick balancing or change the distribution of the changes in speed made by the fingertip during stick balancing, but does decrease the amplitude of the fluctuations in the relative positions of the fingertip and the tip of the stick in the horizontal plane, A(x,y). The findings are interpreted in terms of a time-delayed “drift and act” control mechanism in which controlling movements are made only when controlled variables exceed a threshold, i.e. the stick survival time measures the time to cross a threshold. The amplitude of the oscillations produced by this mechanism can be decreased by parametric excitation. It is shown that a plot of the logarithm of the vibration-induced increase in stick balancing skill, a measure of the mean first passage time, versus the standard deviation of the A(x,y) fluctuations, a measure of the distance to the threshold, is linear as expected for the times to cross a threshold in a stochastic dynamical system. These observations suggest that the balanced state represents a complex time–dependent state which is situated in a basin of attraction that is of the same order of size. The fact that vibration amplitude can benefit balance control raises the possibility of minimizing risk of falling through appropriate changes in the design of footwear and roughness of the walking surfaces
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