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Exploring the implementation of the Last PlannerÂź System through IGLC community: twenty one years of experience
There is robust evidence that the level of implementation of the Last PlannerÂź System (LPS) is increasing geographically and geometrically in construction. The I nternational Group for Lean Construction (IGLC) community has reported this growth at IGLC conferences over this period. However, no study has explored how the LPS and its implementation has developed or improved. This study explored developments in the LPS from the review of IGLC conference papers. Qualitative research design utilising content analysis was adopted for this study comprising 57 IGLC reports on LPS implementation across 16 countries. The study reveals components of LPS implemented, with measuring of PPC, Weekly Work Planning meeting and recording reasons for non-completion the most reported. The study developed a timeline for the LPS development and revealed that some of the papers reviewed have no defined methodology. The study concludes that the LPS has developed in terms of its level of implementation, theory development, and as a vehicle to improve construction management practice across the major continents of the world, with elements that had little presence at the onset now prominent. The study recommends that more attention should be given to the relationship between practical applications and research methods to aid the establishment of sound theory to improve practice
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The magic of the Last PlannerÂź System for Nigerian construction
Extremely poor economic performance of the Nigerian construction industry suggests that non-value adding activities are prevalent, which result not only in the reduction of contractorsâ profit margin but economic loss for the country in general. This study analyses non-value adding activities in Nigerian construction sites. The research seeks to establish potential antidotes within the Last PlannerÂź System (LPS) and reveal the elements of the LPS which could be abstracted into Nigerian construction to improve performance. It was found that these elements form the theoretical basis for developing a lean approach that was labelled Last PlannerÂź thinking
Silencers: A Threat to Public Safety
A push by the firearms industry and gun lobby to make it far easier for private citizens to buy and possess firearm silencers will only place the police and public at increased risk warns a new and expanded edition of the Violence Policy Center's (VPC) study Silencers: A Threat to Public Safety. In detailing this marketing push, the study also documents examples of lethal attacks and criminal activity involving silencers
Absolute proteomic quantification reveals design principles of sperm flagellar chemosensation
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Troetschel, C., Hamzeh, H., Alvarez, L., Pascal, R., Lavryk, F., Boenigk, W., Koerschen, H. G., Mueller, A., Poetsch, A., Rennhack, A., Gui, L., Nicastro, D., Struenker, T., Seifert, R., & Kaupp, U. B. Absolute proteomic quantification reveals design principles of sperm flagellar chemosensation. Embo Journal, 39(4), (2020): e102723, doi:10.15252/embj.2019102723.Cilia serve as cellular antennae that translate sensory information into physiological responses. In the sperm flagellum, a single chemoattractant molecule can trigger a Ca2+ rise that controls motility. The mechanisms underlying such ultraâsensitivity are illâdefined. Here, we determine by mass spectrometry the copy number of nineteen chemosensory signaling proteins in sperm flagella from the sea urchin Arbacia punctulata. Proteins are up to 1,000âfold more abundant than the free cellular messengers cAMP, cGMP, H+, and Ca2+. Optoâchemical techniques show that high protein concentrations kinetically compartmentalize the flagellum: Within milliseconds, cGMP is relayed from the receptor guanylate cyclase to a cGMPâgated channel that serves as a perfect chemoâelectrical transducer. cGMP is rapidly hydrolyzed, possibly via âsubstrate channelingâ from the channel to the phosphodiesterase PDE5. The channel/PDE5 tandem encodes cGMP turnover rates rather than concentrations. The rateâdetection mechanism allows continuous stimulus sampling over a wide dynamic range. The textbook notion of signal amplificationâfew enzyme molecules process many messenger moleculesâdoes not hold for sperm flagella. Instead, high protein concentrations ascertain messenger detection. Similar mechanisms may occur in other small compartments like primary cilia or dendritic spines.We thank Heike Krause for preparing the manuscript. Financial support by the Deutsche Forschungsgemeinschaft (DFG) via the priority program SPP 1726 âMicroswimmersâ and the Cluster of Excellence 1023 âImmunoSensationâ is gratefully acknowledged. We thank D. Stoddard for management of the UTSW cryoâelectron microscope facility, which is funded in part by a Cancer Prevention and Research Institute of Texas (CPRIT) Core Facility Award (RP170644). This study was supported by HHS|National Institutes of Health (NIH) grant R01 GM083122 and by CPRIT grant RR140082 to D. Nicastro
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