900 research outputs found
The impact of human-centric public transport design principles on the desirability and operational success of public transport in the Gauteng province
Papers presented virtually at the 41st International Southern African Transport Conference on 10-13 July 2023.Commuters in South Africa rely on a variety of public transport (PT) modes every day to
access various social and economic opportunities like the workplace, academic
institutions, and healthcare. However, captive, reliant commuters are disappointed on
countless occasions by unsafe, unreliable transport services and feel transport authorities
and modal operators remain indifferent towards their needs and complaints, as solutions
being implemented fail to address the actual problems needing attention and commuters
are not consulted during PT service design. There exists a need to permanently close this
negative cycle by ethically providing for the travel demands of captive lower-income
commuters and establish a transport culture based in making human needs the centre of
design thinking.
This research paper describes an investigation into whether the inclusion of human-centric
design (HCD) in the service- and operational design of PT in the Gauteng Province (GP) of
South Africa, would establish a customer-orientated transport culture, and whether more
human-centric transport service provision would appeal to commuters and address their
specific travel needs and desires. This includes investigating how the priorities of transport
institutions can be aligned with the core needs and desires of the commuters they serve,
so a harmonious yet practical relationship can be cultivated between these stakeholders.
Devised from primary research and global literature findings, the study tested five
principles that combine principles of HCD and PT that were validated by a sample of 300
Gauteng commuters. The findings show that for PT services to be supported, successful
and harmonised in Gauteng, the following is necessary: authentic, collaborative
stakeholder consultation between leaders, designers and commuters; integrated PT
control centres; practical empathy for commuters; centralising human needs, desires, and
feedback in the PT design process, and enhancing a commuter’s perception and
perceived value of a PT service. These principles can be used in the PT design process to
promote elevated customer satisfaction, desirability to use PT and, in turn, the operational
success of Gauteng’s PT services
Discussion of "Accelerated motion of a spherical particle"
In considering the accelerated motion of spheres in a viscous fluid, the author has
restricted himself to consideration of only simple harmonic motions of the fluid field and the sphere.
The author's equation of motion (Eq. 11) for a suspended sphere is true only when the solution yields
a relative displacement (x- a) which is sinusoidal in time. Otherwise, the apparent mass factor k,
and the damping coefficient A have no meaning, because they are both based on the Stokes solution
for an oscillating sphere given in LAMB (1945, see References at end of published paper, p. 721}.
Both k and A are functions of the circular frequency ω as they are defined by (1), (2), and (3)
Effects of urodilatin on natriuresis in cirrhosis patients with sodium retention
BACKGROUND: Sodium retention and ascites are serious clinical problems in cirrhosis. Urodilatin (URO) is a peptide with paracrine effects in decreasing sodium reabsorption in the distal nephron. Our aim was to investigate the renal potency of synthetic URO on urine sodium excretion in cirrhosis patients with sodium retention and ascites. METHODS: Seven cirrhosis patients with diuretics-resistant sodium retention received a short-term (90 min) infusion of URO in a single-blind, placebo-controlled cross-over study. In the basal state after rehydration the patients had urine sodium excretion < 50 mmol/24 h. RESULTS: URO transiently increased urine sodium excretion from 22 ± 16 μmol/min (mean ± SD) to 78 ± 41 μmol/min (P < 0.05) and there was no effect of placebo (29 ± 14 to 44 ± 32). The increase of URO's second messenger after the receptor, cGMP, was normal. URO had no effect on urine flow or on blood pressure. Most of the patients had highly elevated plasma levels of renin, angiotensin II and aldosterone and URO did not change these. CONCLUSION: The short-term low-dose URO infusion increased the sodium excretion of the patients. The increase was small but systematic and potentially clinically important for such patients. The small response contrasts the preserved responsiveness of the URO receptors. The markedly activated systemic pressor hormones in cirrhosis evidently antagonized the local tubular effects of URO
Optimización de la producción de biomasa usando glicerol crudo, de una cepa mutante de Yarrowia lipolytica con actividad incrementada de lipasa
218-225The yeast Yarrowia lipolytica accumulates oils and is able to produce extracellular lipases when growing in different carbon sources including glycerol, the principal by-product of the biodiesel industry. In this study, biomass production of a novel mutant strain of Y. lipolytica was statistically optimized by Response Surface Methodology in media containing biodiesel-derived glycerol as main carbon source. This strain exhibited distinctive morphological and fatty acid profile characteristics, and showed an increased extracellular lipase activity. An organic source of nitrogen and the addition of 1.0 g/l olive oil were necessary for significant lipase production. Plackett-Burman and Central Composite Statistical Designs were employed for screening and optimization of fermentation in shaken flasks cultures, and the maximum values obtained were 16.1 g/l for biomass and 12.2 Units/ml for lipase, respectively. Optimized batch bioprocess was thereafter scaled in aerated bioreactors and the values reached for lipase specific activity after 95 percent of the glycerol had been consumed, were three-fold higher than those obtained in shaken flasks cultures. A sustainable bioprocess to obtain biomass and extracellular lipase activity was attained by maximizing the use of the by-products of biodiesel industry
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Does habitat stability structure intraspecific genetic diversity? It’s complicated...
Regional phylogeographic studies have long been conducted in the southeastern United States for a variety of species. With some exceptions, many of these studies focus on single species or single clades of organisms, and those considering multiple species tend to focus on deep historical breaks causing differentiation. However, in many species more recent factors may be influencing genetic diversity. To understand the roles of historic and contemporary processes in structuring genetic diversity, we reanalyzed existing genetic data from Southeast of North America using approaches gleaned from phylogeographic and landscape genetic literature that were implemented across species including AMOVAs, PCoAs, Species Distribution Modelling, and tests of isolation by distance, environment, and habitat instability. Genetic variance was significantly partitioned by ecoregions, watersheds, and across phylogeographic breaks in the majority of species. Similarly, genetic variation was significantly associated with some combination of geographic or environmental distance or habitat instability in most species. Patterns of genetic variation were largely idiosyncratic across species. While habitat instability over time is significantly correlated with genetic diversity in some species, it appears generally less important than isolation by geographic or environmental distance. Our results suggest that many factors, both historical and contemporary, impact genetic diversity within a species, and more so, that these patterns aren’t always similar in closely related species. This supports the importance of species- specific factors and cautions against assumptions that closely related species will respond to historical and contemporary forces in similar ways
Task analysis method for procedural training curriculum development
A central venous catheter (CVC) is an important medical tool used in critical care and emergent situations. Integral to proper care in many circumstances, insertion of a CVC introduces the risk of central line-associated blood stream infections and mechanical adverse events; proper training is important for safe CVC insertion. Cognitive task analysis (CTA) methods have been successfully implemented in the medical field to improve the training of postgraduate medical trainees, but can be very time-consuming to complete and require a significant time commitment from many subject matter experts (SMEs). Many medical procedures such as CVC insertion are linear processes with well-documented procedural steps. These linear procedures may not require a traditional CTA to gather the information necessary to create a training curriculum. Accordingly, a novel, streamlined CTA method designed primarily to collect cognitive cues for linear procedures was developed to be used by medical professionals with minimal CTA training. This new CTA methodology required fewer trained personnel, fewer interview sessions, and less time commitment from SMEs than a traditional CTA. Based on this study, a streamlined CTA methodology can be used to efficiently gather cognitive information on linear medical procedures for the creation of resident training curricula and procedural skills assessments
The Fundamental Diagram of Pedestrian Movement Revisited
The empirical relation between density and velocity of pedestrian movement is
not completely analyzed, particularly with regard to the `microscopic' causes
which determine the relation at medium and high densities. The simplest system
for the investigation of this dependency is the normal movement of pedestrians
along a line (single-file movement). This article presents experimental results
for this system under laboratory conditions and discusses the following
observations: The data show a linear relation between the velocity and the
inverse of the density, which can be regarded as the required length of one
pedestrian to move. Furthermore we compare the results for the single-file
movement with literature data for the movement in a plane. This comparison
shows an unexpected conformance between the fundamental diagrams, indicating
that lateral interference has negligible influence on the velocity-density
relation at the density domain . In addition we test a
procedure for automatic recording of pedestrian flow characteristics. We
present preliminary results on measurement range and accuracy of this method.Comment: 13 pages, 9 figure
Detecting deceptive reviews using argumentation
The unstoppable rise of social networks and the web is facing a serious challenge: identifying the truthfulness of online opinions and reviews. In this paper we use Argumentation Frameworks (AFs) extracted from reviews and explore whether the use of these AFs can improve the performance of machine learning techniques in detecting deceptive behaviour, resulting from users lying in order to mislead readers. The AFs represent how arguments from reviews relate to arguments from other reviews as well as to arguments about the goodness of the items being reviewed
Asymmetric Synthesis of 1-Heteroaryl-1-arylalkyl Tertiary Alcohols and 1-Pyridyl-1-arylethanes by Lithiation-Borylation Methodology
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