Laser scabbling of mortars

Laser scabbling of concrete is the process by which the surface layer of concrete may be removed through the use of a low power density laser beam. Previous research has suggested that the driving force responsible for laser scabbling is developed within the mortar. The aim of this investigation was to establish the key parameters that influence laser scabbling of mortars. The results show that the removal of free water from mortars prohibits scabbling, but resaturation allows mortar to scabble. A reduced permeability, either due to a reduction in the water/binder ratio or the use of 25% PFA replacement, enhances the scabbling. A higher fine aggregate content increases volume removal and fragment sizes during laser scabbling

CO17 107. Experiencia inicial con la prótesis de válvula aórtica sin sutura 3f-enable de segunda generación

ObjetivosLa válvula aórtica ATS-3F-Enable™ representa una nueva generación con pericardio equino, stent de nitinol autoexpandible e implantación sin suturas. Evaluamos la técnica de implantación, la seguridad y efectividad de la válvula así como los resultados al año de implantación.Material y métodosAnálisis de resultados en una serie de 27 pacientes consecutivos con estenosis de válvula aórtica y reemplazamiento aislado de la válvula por una ATS-3F-Enable™ entre agosto de 2007 y febrero de 2009. La edad media fue 75,7±6,6 años. Diecisiete mujeres (63%). EuroSCORE mediano: 8, y medio: 7,1±1,7.ResultadosEl tamaño medio de válvula implantada fue de 23mm (franja: 19-27mm). La media de tiempo de clampaje aórtico fue de 39,8±15min (franja: 29-103min). La media de tiempo de circulación extracorpórea fue de 58,6±20min (franja: 41-127). La media de tiempo de hospitalización fue de 11 días (7-22). No hubo mortalidad durante la intervención. Al alta, los gradientes de presión transvalvular medio y alto con ecocardiografía fueron de 11,6 y 18,5mmHg, respectivamente. Dos pacientes presentaron una fuga paravalvular moderada y un paciente fue reoperado a causa de una fuga paravalvular grave. Se requirió la implantación de marcapasos en cinco pacientes (18,5%). El seguimiento al cabo de 1 año fue del 100% y la supervivencia fue del 86%.ConclusionesLa prótesis aórtica ATS-3F-Enable™ puede ser implantada con seguridad y presenta resultados hemodinámicos favorables. El stent autoexpandible y la técnica sin sutura permite una implantación rápida, sin embargo, no tan rápida como esperado. Acumulación de experiencia y algunas modificaciones en el diseño de la prótesis podrán ayudar a perfeccionar la técnica

Escherichia coli MazF Leads to the Simultaneous Selective Synthesis of Both “Death Proteins” and “Survival Proteins”

The Escherichia coli mazEF module is one of the most thoroughly studied toxin–antitoxin systems. mazF encodes a stable toxin, MazF, and mazE encodes a labile antitoxin, MazE, which prevents the lethal effect of MazF. MazF is an endoribonuclease that leads to the inhibition of protein synthesis by cleaving mRNAs at ACA sequences. Here, using 2D-gels, we show that in E. coli, although MazF induction leads to the inhibition of the synthesis of most proteins, the synthesis of an exclusive group of proteins, mostly smaller than about 20 kDa, is still permitted. We identified some of those small proteins by mass spectrometry. By deleting the genes encoding those proteins from the E. coli chromosome, we showed that they were required for the death of most of the cellular population. Under the same experimental conditions, which induce mazEF-mediated cell death, other such proteins were found to be required for the survival of a small sub-population of cells. Thus, MazF appears to be a regulator that induces downstream pathways leading to death of most of the population and the continued survival of a small sub-population, which will likely become the nucleus of a new population when growth conditions become less stressful

Patterns of Cost for Patients Dying in the Intensive Care Unit and Implications for Cost Savings of Palliative Care Interventions.

BACKGROUND: Terminal intensive care unit (ICU) stays represent an important target to increase value of care. OBJECTIVE: To characterize patterns of daily costs of ICU care at the end of life and, based on these patterns, examine the role for palliative care interventions in enhancing value. DESIGN: Secondary analysis of an intervention study to improve quality of care for critically ill patients. SETTING/PATIENTS: 572 patients who died in the ICU between 2003 and 2005 at a Level-1 trauma center. METHODS: Data were linked with hospital financial records. Costs were categorized into direct fixed, direct variable, and indirect costs. Patterns of daily costs were explored using generalized estimating equations stratified by length of stay, cause of death, ICU type, and insurance status. Estimates from the literature of effects of palliative care interventions on ICU utilization were used to simulate potential cost savings under different time horizons and reimbursement models. MAIN RESULTS: Mean cost for a terminal ICU stay was 39.3K ± 45.1K. Direct fixed costs represented 45% of total hospital costs, direct variable costs 20%, and indirect costs 34%. Day of admission was most expensive (mean 9.6K ± 7.6K); average cost for subsequent days was 4.8K ± 3.4K and stable over time and patient characteristics. CONCLUSIONS: Terminal ICU stays display consistent cost patterns across patient characteristics. Savings can be realized with interventions that align care with patient preferences, helping to prevent unwanted ICU utilization at end of life. Cost modeling suggests that implications vary depending on time horizon and reimbursement models

The effect of ageing and drying on laser scabbling of concrete

Laser scabbling of concrete is a process by which the surface layer of concrete is removed through the use of a high power (low power density) laser beam. In order to understand how the age and treatment of structures may affect the laser scabbling process, the aim of the research presented in this paper was to establish a relationship between laser interaction time, surface temperature and volume removal for cementitious materials of different ages and different degrees of saturation. The investigation focussed on (i) the effect of age on saturated specimens and (ii) the effect of prolonged drying. The results show that drying of specimens had the largest effect on scabbling. The effect of age on saturated specimens was small for PFA + OPC pastes, mortars and concretes, but significant for OPC pastes, where the volume of scabbling dramatically reduced with age

Fussing About Fission: Defining Variety Among Mainstream and Exotic Apicomplexan Cell Division Modes

Cellular reproduction defines life, yet our textbook-level understanding of cell division is limited to a small number of model organisms centered around humans. The horizon on cell division variants is expanded here by advancing insights on the fascinating cell division modes found in the Apicomplexa, a key group of protozoan parasites. The Apicomplexa display remarkable variation in offspring number, whether karyokinesis follows each S/M-phase or not, and whether daughter cells bud in the cytoplasm or bud from the cortex. We find that the terminology used to describe the various manifestations of asexual apicomplexan cell division emphasizes either the number of offspring or site of budding, which are not directly comparable features and has led to confusion in the literature. Division modes have been primarily studied in two human pathogenic Apicomplexa, malaria-causing Plasmodium spp. and Toxoplasma gondii, a major cause of opportunistic infections. Plasmodium spp. divide asexually by schizogony, producing multiple daughters per division round through a cortical budding process, though at several life-cycle nuclear amplifications stages, are not followed by karyokinesis. T. gondii divides by endodyogeny producing two internally budding daughters per division round. Here we add to this diversity in replication mechanisms by considering the cattle parasite Babesia bigemina and the pig parasite Cystoisospora suis. B. bigemina produces two daughters per division round by a “binary fission” mechanism whereas C. suis produces daughters through both endodyogeny and multiple internal budding known as endopolygeny. In addition, we provide new data from the causative agent of equine protozoal myeloencephalitis (EPM), Sarcocystis neurona, which also undergoes endopolygeny but differs from C. suis by maintaining a single multiploid nucleus. Overall, we operationally define two principally different division modes: internal budding found in cyst-forming Coccidia (comprising endodyogeny and two forms of endopolygeny) and external budding found in the other parasites studied (comprising the two forms of schizogony, binary fission and multiple fission). Progressive insights into the principles defining the molecular and cellular requirements for internal vs. external budding, as well as variations encountered in sexual stages are discussed. The evolutionary pressures and mechanisms underlying apicomplexan cell division diversification carries relevance across Eukaryota

Comparing quality of dying and death perceived by family members and nurses for patients dying in US and Dutch ICUs

BACKGROUND: The Quality of Dying and Death (QODD) questionnaire is used as a selfreported measure to allow families and clinicians to assess patients' quality of dying and death. We evaluated end-of-life (EOL) experiences as measured by the QODD completed by families and nurses in the United States and the Netherlands to explore similarities and differences in these experiences and identify opportunities for improving EOL care. METHODS: Questionnaire data were gathered from family members of patients dying in the ICU and nurses caring for these patients. In The Netherlands, data were gathered in three teaching hospitals, and data was gathered from 12 sites participating in a randomized trial in the United States. The QODD consists of 25 items and has been validated in the United States. RESULTS: Data from 446 patients were analyzed (346 in the United States and 100 in the Netherlands). Dutch patients were older than those in the United States (72 + 10.2 years vs 65 + 16.0 years; P <.0025). The family-assessed overall QODD score was the same in both countries: the Netherlands = median, 9; interquartile range (IQR), 8-10 and the United States = median, 8; IQR, 5-10. US family members rated the quality of two items higher than did the Netherlands families: "time spent with loved ones" and "time spent alone." Nurseassessed QODD ratings varied: the single-item QODD summary score was significantly higher in the Netherlands (the Netherlands: median, 9; IQR, 8-10 vs the United States: median, 7; IQR, 5-8; P <.0025), whereas the QODD total score was higher in the United States (the Netherlands: median, 6.9; IQR, 5.5-7.6 vs the United States: median, 7.1; IQR, 5.88.4; P = .014), although it did not meet our criteria for statistical significance. Of the 22 nurse-assessed items, 10 were significantly different between the Netherlands and the United States, with eight having higher scores in the United States and 2 having higher scores in the Netherlands. CONCLUSIONS: The QODD was rated similarly by family members in the United States and the Netherlands but varied when assessed by nurses. These differences may be due to organizational or cultural differences between the two countries or to expectations of respondents

A Differential Effect of E. coli Toxin-Antitoxin Systems on Cell Death in Liquid Media and Biofilm Formation

Toxin-antitoxin (TA) modules are gene pairs specifying for a toxin and its antitoxin and are found on the chromosomes of many bacteria including pathogens. Here we report how each of five such TA systems in E. coli affect bacterial cell death differently in liquid media and during biofilm formation. Of all these systems, only the TA system mazEF mediated cell death both in liquid media and during biofilm formation. At the other extreme, as our results have revealed here, the TA system dinJ-YafQ is unique in that it is involved only in the death process during biofilm formation. Cell death governed by mazEF and dinJ-YafQ seems to participate in biofilm formation through a novel mechanism