Prospective monitoring improves outcomes of primary total hip replacement: a cohort study

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Memory in Microbes: Quantifying History-Dependent Behavior in a Bacterium

Memory is usually associated with higher organisms rather than bacteria. However, evidence is mounting that many regulatory networks within bacteria are capable of complex dynamics and multi-stable behaviors that have been linked to memory in other systems. Moreover, it is recognized that bacteria that have experienced different environmental histories may respond differently to current conditions. These “memory” effects may be more than incidental to the regulatory mechanisms controlling acclimation or to the status of the metabolic stores. Rather, they may be regulated by the cell and confer fitness to the organism in the evolutionary game it participates in. Here, we propose that history-dependent behavior is a potentially important manifestation of memory, worth classifying and quantifying. To this end, we develop an information-theory based conceptual framework for measuring both the persistence of memory in microbes and the amount of information about the past encoded in history-dependent dynamics. This method produces a phenomenological measure of cellular memory without regard to the specific cellular mechanisms encoding it. We then apply this framework to a strain of Bacillus subtilis engineered to report on commitment to sporulation and degradative enzyme (AprE) synthesis and estimate the capacity of these systems and growth dynamics to ‘remember’ 10 distinct cell histories prior to application of a common stressor. The analysis suggests that B. subtilis remembers, both in short and long term, aspects of its cell history, and that this memory is distributed differently among the observables. While this study does not examine the mechanistic bases for memory, it presents a framework for quantifying memory in cellular behaviors and is thus a starting point for studying new questions about cellular regulation and evolutionary strategy

Engineering of cyclodextrin glucanotransferases and the impact for biotechnological applications

Cyclodextrin glucanotransferases (CGTases) are industrially important enzymes that produce cyclic α-(1,4)-linked oligosaccharides (cyclodextrins) from starch. Cyclodextrin glucanotransferases are also applied as catalysts in the synthesis of glycosylated molecules and can act as antistaling agents in the baking industry. To improve the performance of CGTases in these various applications, protein engineers are screening for CGTase variants with higher product yields, improved CD size specificity, etc. In this review, we focus on the strategies employed in obtaining CGTases with new or enhanced enzymatic capabilities by searching for new enzymes and improving existing enzymatic activities via protein engineering

DNA replication fidelity in Mycobacterium tuberculosis is mediated by an ancestral prokaryotic proofreader

The DNA replication machinery is an important target for antibiotic development for increasingly drug resistant bacteria including Mycobacterium tuberculosis1. While blocking DNA replication leads to cell death, disrupting the processes used to ensure replication fidelity can accelerate mutation and the evolution of drug resistance. In E. coli, the proofreading subunit of the replisome, the ε-exonuclease, is essential for high fidelity DNA replication2; however, we find that it is completely dispensable in M. tuberculosis. Rather, the mycobacterial replicative polymerase, DnaE1, encodes a novel editing function that proofreads DNA replication, mediated by an intrinsic 3′-5′ exonuclease activity within its PHP domain. Inactivation of the DnaE1 PHP domain increases the mutation rate by greater than 3,000 fold. Moreover, phylogenetic analysis of DNA replication proofreading in the bacterial kingdom suggests that E. coli is a phylogenetic outlier and that PHP-domain mediated proofreading is widely conserved and indeed may be the ancestral prokaryotic proofreader

Evaluation for Fatigue Data of UTWT Pavement using Fiber Reinforced Concrete

This study aimed to Fatigue Data analyses of Ultra-Thin White Topping (UTWT) pavement under the various loading condition of vehicles. Ultra-Thin White Topping is a concrete overlay on deteriorated bituminous and hot mix asphalt (HMA) pavement. This concrete overlay constructed by using concrete having high grade. Plain cement concrete having less flexural strength than reinforced concrete. The fiber reinforced concrete is used for construction of UTWT pavements at various sites around the world. The pavement constructed using FRC are gives better results than the plain concrete. This paper mainly highlights the evaluation of pavement using polypropylene fibers. The fibers added in concrete to improve the flexural strength of pavement. UTWT pavements thickness varies from 50-100 mm. For speedy construction work fiber, reinforced concrete generally used. This paper highlights the evaluation of road 2 km long, situated at MIDC Area, Amravati, INDIA. This pavement analyses using the guidelines given by Indian Roads Congress

Evaluation for Fatigue Data of UTWT Pavement using Fiber Reinforced Concrete

This study aimed to Fatigue Data analyses of Ultra-Thin White Topping (UTWT) pavement under the various loading condition of vehicles. Ultra-Thin White Topping is a concrete overlay on deteriorated bituminous and hot mix asphalt (HMA) pavement. This concrete overlay constructed by using concrete having high grade. Plain cement concrete having less flexural strength than reinforced concrete. The fiber reinforced concrete is used for construction of UTWT pavements at various sites around the world. The pavement constructed using FRC are gives better results than the plain concrete. This paper mainly highlights the evaluation of pavement using polypropylene fibers. The fibers added in concrete to improve the flexural strength of pavement. UTWT pavements thickness varies from 50-100 mm. For speedy construction work fiber, reinforced concrete generally used. This paper highlights the evaluation of road 2 km long, situated at MIDC Area, Amravati, INDIA. This pavement analyses using the guidelines given by Indian Roads Congress