•Navigation accidents are associated with some vessel types, and length of the vessel.•Associated vessel types are cargo, bulk, tankers, well boats, and fishing vessels.•Poor visibility increases the ...probability of a navigation accident.•Flag of convenience increase the probability of a navigation accident.•38.4% of the variance in the dependent variable is explained.
This paper presents the results of statistical analyses of maritime accidents data and AIS data from Norwegian waters, to identify conditions that are associated with navigation related accidents (groundings and collisions) and could be used as risk indicators. Vessels involved in accidents reported in the accident database of the Norwegian Maritime Directorate (NMA), have been traced in historical AIS records, and data related to each ship have been transformed into variables. These variables are related to the behavior of the ship in front of the accident (e.g. nautical miles sailed, hours in operations, number of port calls etc.), technical and organizational conditions (ship categories, flag state, age, gross tonnage, Paris MoU ratings etc.) and the area where the accident occurred (number of vessels in the area, port calls in the area, nautical miles in the area etc.). Both the AIS data and the data from the NMA accident database have first been analyzed using correspondence analysis (categorical variables), F-tests (continuous variables), and then combined in a multivariate logistic regression model with “navigation accidents” and “other accidents” as dependent variables. The model is a strong predictor for whether the accident is navigation-related or not. Specifically, some vessel types, less vessel length, poor visibility condition, and a flag of convenience increased this probability.
The accident levels in helicopter transportation vary between geographical regions and types of operations. In this paper, we develop some hypotheses regarding the factors that may explain this ...variation. The aim of this paper is to improve safety in helicopter transportation through better understanding of the causes leading to fatal accidents. We provide an analysis of three segments of helicopter transportation in Norway (i.e., offshore transportation; onshore ambulance/police, and onshore transportation). This analysis refers to international research on helicopter accidents. The number of fatal accidents per million flight hours in Norwegian offshore helicopter transportation was 2.8 in 1990–1999 and zero in 2000–2015. In Norwegian onshore helicopter transportation, the fatal accident rate was 13.8 in the period 2000–2012. Twenty-three onshore helicopters crashed to the ground; seven of these crashes were fatal, killing 16 people. It is reasonable to question why there is such a significant difference in accident rates between offshore and onshore helicopter transportation. We have approached this question by comparing how the different segments of helicopter transportation are organized and managed. Our analysis shows that there are major differences both at the “sharp” end (i.e., in actual operations) and the “blunt” end (i.e., rules, regulations and organization). This includes differences in regulations, market conditions, work organization (i.e., training, employment conditions, and qualifications of the crews), operations and technology. A central argument is that differences in the market conditions and requirements stipulated by the users explain some of these differences. The same differences can be found internationally. If we use best practice and expert judgments, there is an opportunity to improve helicopter safety through improving the socio-technical system (i.e., organizational issues, improved design, improved maintenance of critical components and more focus on operational factors). A reasonable goal is that the international helicopter transportation industry could reduce the accident level to less than one fatal accident per million flight hours (Considering the oil and gas industry internationally, this would reduce the average of 24 fatalities annually to 4 per year, thus saving 20 lives each year).
Nicotinic acetylcholine receptors (nAChRs) are master regulators of immune functions via the cholinergic anti-inflammatory pathway and are expressed in microglia, the brain’s resident immune cells. ...There is an extensive dialogue between the neurons and the glial cells around them from which microglia are tasked with monitoring, nurturing, and defending their microenvironment. Dysregulation of any of these processes can have devastating and long-lasting consequences involving microglia-mediated neuroinflammation associated with neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease, amongst others. Disease-associated microglia acquire a distinguishing phenotype that emphasizes scavenging and defence functions while nurturing and repairing functions become muted. Attempts to resolve this critical imbalance remain a key focus of research. Furthermore, cholinergic modulation of neuroinflammation represents a promising avenue for treatment.
Calcium Imaging of Non-adherent Cells Bye, Lydia J; Finol-Urdaneta, Rocio K; Adams, David J
Methods in molecular biology (Clifton, N.J.),
2023, Letnik:
2644
Journal Article
Live-cell imaging can reveal dynamic and multimodal cell signaling by monitoring calcium flux. Spatiotemporal changes in Ca
concentrations instigate specific downstream processes and by categorizing ...these events, we can examine the language cells use to communicate both to themselves and with each other. Thus, calcium imaging is an understandably popular and versatile technique that relies on high-resolution optical data as measured by fluorescence intensity. This is executed with relative ease on adherent cells, as changes in fluorescence intensity can be monitored over time in fixed regions of interest. However, perfusion of non-adherent or mildly adherent cells leads to their mechanical displacement thereby hindering the spatial resolution of fluorescence intensity changes through time. Here we provide details of a simple and cost-effective protocol using gelatin to prevent cell dislodgement during the solution exchanges that occur during recording.
Composite tissue-engineered constructs combining bone and soft tissue have applications in regenerative medicine, particularly dentistry. This study generated a tri-layer, electrospun, ...poly-ε-caprolactone membrane, with two microfiber layers separated by a layer of nanofibers, for the spatially segregated culture of mesenchymal progenitor cells (MPCs) and fibroblasts. The two cell types were seeded on either side, and cell proliferation and spatial organization were investigated over several weeks. Calcium deposition by MPCs was detected using xylenol orange (XO) and the separation between fibroblasts and the calcified matrix was visualized by confocal laser scanning microscopy. SEM confirmed that the scaffold consisted of two layers of micron-diameter fibers with a thin layer of nano-diameter fibers in-between. Complete separation of cell types was maintained and calcified matrix was observed on only one side of the membrane. This novel tri-layer membrane is capable of supporting the formation of a bilayer of calcified and non-calcified connective tissue.
The Geoscience Laser Altimeter System (GLAS) has the potential to accurately map global vegetation heights and fractional cover metrics using active laser pulse emission/reception. However, large ...uncertainties in the derivation of data products exist, since multiple physically plausible interpretations of the data are possible. In this study a method is described and evaluated to derive vegetation height and fractional cover from GLAS waveforms by inversion of the FLIGHT radiative transfer model. A lookup-table is constructed giving expected waveforms for a comprehensive set of canopy realisations, and is used to determine the most likely set of biophysical parameters describing the forest structure, consistent with any given GLAS waveform. The parameters retrieved are canopy height, leaf area index (LAI), fractional cover and ground slope. The range of possible parameters consistent with the waveform is used to give a per-retrieval uncertainty estimate for each retrieved parameter. The retrieved estimates were evaluated first using a simulated data set and then validated against airborne laser scanning (ALS) products for three forest sites coincident with GLAS overpasses. Results for height retrieval show mean absolute error (MAE) of 3.71m for a mixed temperate forest site within Forest of Dean (UK), 3.35m for the Southern Old Aspen Site, Saskatchewan, Canada, and 5.13m for a boreal coniferous site in Norunda, Sweden. Fractional cover showed MAE of 0.10 for Forest of Dean and 0.23 for Norunda. Coefficient of determination between ALS and GLAS estimates over the combined dataset gave R2 values of 0.71 for height and 0.48 for fractional cover, with biases of −3.4m and 0.02 respectively. Smallest errors were found where overpass dates for ALS data collection closely matched GLAS overpasses. Explicit instrument parameterisation means the method is readily adapted to future planned spaceborne LiDAR instruments such as GEDI.
•We invert a Monte-Carlo waveform LiDAR canopy reflectance model.•A LUT is used to estimate canopy parameters in 3 study sites.•Vegetation height, fractional cover and slope can be estimated simultaneously.
Functional imaging of the intracellular calcium concentration Ca2+i using fluorescent indicators is a powerful and frequently applied method for assessing various biological questions in vitro, ...including ion channel function and intracellular signaling in homeostasis and disease. In functional Ca2+i imaging experiments, the fluorescence intensity of single cells is typically recorded during application of a chemical stimulus, i.e. by exchange of modified extracellular media, exposure to drugs and/or ligands. The concomitant mechanical perturbation caused by the perfusion of different solution during experimentation severely hinders calcium imaging in non-adherent cells, including peripheral immune cells, as cells in suspension are dislocated by turbulent flow during chemical stimulation. The quantitative analysis, involving time-courses of intracellular fluorescence signal changes, necessitates cells to remain at the same position throughout the experiment. To prevent dislocation of cells during solution exchange, and to enable imaging as well as analysis of Ca2+ responses in immune cells, a gelatin-based method for immobilization of non-adherent cells was developed. Gelatin has been a long-serving material for cell immobilization, e.g. in 3D bio-printing of cells and has thus, also been employed in the context of this study. To demonstrate the applicability of the established method for functional Ca2+ imaging in gelatin-immobilized suspension cells, a proof-of-concept study was conducted using human peripheral blood model cell lines (Jurkat/T-lymphocytes and THP-1/monocytes), Ca2+ indicators (Fluo-4 and Fura-2) and two different fluorescence microscopy rigs. The data presented that the established methodology is applicable for studying Ca2+ signaling by in vitro high-content functional imaging of Ca2+i in suspension cells, including but not restricted to human immune cells.
•A cost-effective gelatin-based method for functional imaging of Ca2+i in non-adherent cells was developed.•A proof-of-concept study was conducted using differently labelled Jurkat/T-lymphocytes and THP-1/monocytes.•The developed protocol could be applied to other non-adherent cell types, indicators and imaging rig configurations.•The method may be suitable for high-throughput screening with non-adherent cells.
Conductivity-temperature-depth (CTD) observations taken in the Great Australian Bight (GAB) during
ORV Franklin cruise Fr 07/94 in July 1994 indicated the presence of a dense bottom layer at the head ...of the GAB, which flowed along the sea floor towards the shelf-break as a gravity current The north central region of the GAB was stratified with a maximum salinity difference of between 0.4 and 0.5. The outflow was confined to the shelf and was directed in a south-easterly direction with little evidence of cross-shelf transport. The flow exhibited a well-defined bottom interface evident from the head of the GAB to near the mouth of Spencer Gulf (SG), where the surface-bottom salinity difference was about 0.3. The mean thickness of the outflow was about 15
m. An estimate of the speed of the outflow at the discharge over the shelf-break was made using the zero entrainment assumption. This yielded a speed of <16
cm
s
−1, which remarkably was consistent with near bottom current meter measurements (16
cm
s
−1) on the continental shelf edge, reported south of the Eyre Peninsula. A mass budget analysis indicated that the outflow, which probably is partially maintained by the gravity current and partly by a wind-driven circulation would exist over the period, July–December, with a peak transport of about 10
6
m
3s
−1 (1 Sverdrup) which is approximately twenty times that of the bottom outflow from the adjoining Spencer Gulf.
•Descriptions of institutional traits of the Norwegian police force.•Institutional traits influence emergency responses to crises.•High complexity and uncertainty activate institutionalized ...responses.•Broader organizational analyzes should be a part of the study of emergency responses.
In this paper we address the institutional context of the police response during the 22 July terror attacks in Norway. Our analysis shows how institutionalized informal practices, established over time, influenced the police response during the attacks. The response presented challenges in terms of management of actor complexity (the number of actors involved and the need for coordination) and uncertainty. The importance of these dimensions is discussed based on the police's response during the terror attack in Oslo in 2011. Our analysis of the course of events shows that the resources dedicated to strategic management were marginalized during the event and that insufficient attention was directed towards intelligence and investigation. This contributed to an ineffective police effort to track and capture the perpetrator and prevent or respond to the secondary attack. This is similar to what is often found in hindsight investigations of crises. The aim of this paper is to contextualize and analyze these findings in light of the institutional context of the Norwegian police. Reports from exercises before and after the terror attack indicate that the marginalization of strategic work, intelligence and investigation has been and remains a persistent problem in the Norwegian police. Interviews indicate that there are informal aspects of the police organization regarding status and established conventions of what “proper police work” is about that explain how the observed inadequacies are deeply embedded in the organization. As such, the paper is not a study of a failure in crisis management, but rather the institutional patterns of action that make actions and decisions stand out as meaningful for the actors involved in dealing with situations of high complexity and uncertainty.
Background
For the past 32 years, we have polled first-year biology students annually at the University of New South Wales concerning their views about evolution and creationism. The purposes of the ...research were to identify the level of commitment among incoming students to creationist beliefs that could interfere with their receptivity to evolutionary science and to assess in retrospect whether these creationist beliefs were changing over time.
Results
The results have demonstrated a downward shift over time from 60% of the class in 1986 believing a god had something to do with the origin of humans, to 29% in 2017. Conversely, the percentage of students convinced that a god had nothing to do with the origin of humans rose from 25% in 1986 to 62% in 2017. The creationist belief that a god created the world de novo within the last 10,000 years declined from 10% in 1986 to 3.6% in 2017. The decline in the Australian students’ commitment to religious views about divine creation, especially creationism, considerably exceeded the corresponding beliefs among American students and their general public, where belief in creationism while slowly declining appears to have remained in the 40% range, four times that seen in our Australian survey.
Conclusions
The very low and declining levels of commitment to the creationist view that god created humans de novo suggests this view is unlikely to be a significant obstruction to accepting the scientific evidence for evolution. The results of the survey of UNSW students correlate with changes documented in the census of the general Australian public suggesting that our survey results of first-year biology students reflect overall changes in the Australian community as a whole.
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