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The influence of perceptual motor variability on the perception of action boundaries for reaching in a real-world setting
No full textThe ability to accurately perceive the extent over which one can act is requisite for the successful execution of visually-guided actions. Yet, like other outcomes of perceptual-motor experience, our perceived action boundaries are not stagnant, but in constant flux. Hence, the perceptual systems must account for variability in one’s action capabilities in order for the perceiver to determine when they are capable of successfully performing an action. Recent work has found that, after reaching with a virtual arm that varied between short and long each time they reach, individuals determined their perceived action boundaries using the most liberal reaching experience. However, these studies were conducted in virtual reality, and the perceptual systems may handle variability differently in a real-world setting. To test this hypothesis, we created a modified orthopaedic elbow brace that mimics injury in the upper limb by restricting elbow extension via remote control. Participants were asked to make reachability judgements after training in which the maximum extent of their reaching ability was either unconstricted, constricted or variable over several calibration trials. Findings from the current study didn’t conform to those in virtual reality; participants were more conservative with their reachability estimates after experiencing variability in a real-world setting
Enhancing separation efficiency in the acetic acid manufacturing by methanol carbonylation
No full textAcetic acid is an essential chemical used in the production of many chemical products. Using methanolas bio-building block, the acetic acid produced may be incorporated in bio-based products. This studydeals with enhancing the efficiency of separations in a process using homogeneous catalyst, which is themost applied today industrially. Several configurations for downstream processing by distillation areinvestigated using effective combinations of fully thermally coupled columns, namely dividing-wallcolumns, alone or combined with heat pumps.The results show that the three-column direct sequence may be effectively replaced by a two-columnsequence. When only full thermally coupled columns are employed, the alternative C1+DWC(C2+C3)performs the best with savings of 25% in CAPEX, 27% in OPEX and 24.5% in CO2 emissions. When vaporcompression is added (using water as working fluid), the alternative DWC(C1+C2)+C3-HP performs thebest. CAPEX remains at 10% under the base-case, while the savings in utilities and CO2 emissions rise to46.8% and 53.3%, respectively. Overall, the total annual cost is reduced by 34%. The cost of compressormay be paid back in 1.5 years by the saved energy. Low energy intensity (under 1 MJ/kg acetic acid) isachieved by tight integration with the reaction section
The Last Caravans in Antiquity: Camel Remains from Caričin Grad (Justiniana Prima)
No full textCamels played an important role in caravan traffic and long-distance communication during the early Byzantine period as indicated by new findings from Caričin Grad. Excavations at Caričin Grad have revealed the remains of an important early Byzantine city, which has been identified with Justiniana Prima founded in the 530s by Justinian I (527–565). The city, created ex nihilo, in a rural area in the north-west of the province of Dacia Mediterranea, represents a distinctive example of late urbanisation. Given the existence of the city for only 80 years and the fact that the nearby locality remained uninhabited until modern times, the site has yielded well-preserved monuments and remains of material culture. Those features of the site allow a detailed study of the urbanism, architecture, material culture and diverse aspects of daily life from the second quarter of the 6th century to the beginning of the 7th century. The following paper describes the camel remains discovered in five locations in Caričin Grad. Morphometric and proteomic analyses, including both collagen peptide mass fingerprint analysis (ZooMS) as well as in-depth sequencing, revealed that the majority of camel remains originate from hybrids of the dromedary and Bactrian camels. Supported by written sources from the Early Byzantine period, it appears as though the use of Caričin Grad camels was primarily for civilian purposes. These results highlight the complementarity of morphometric and proteomic approaches and their value in better understanding the impact of the early Byzantine economy
Tailoring Equiaxed β-grain Structures in Ti-6Al-4V Coaxial Electron Beam Wire Additive Manufacturing
No full textHigh-deposition-rate, directed-energy-deposition additive manufacturing (DED-AM) processes typically produce Ti-6Al-4V (Ti64) components with coarse columnar β-grain structures that lead to undesirable mechanical anisotropy, as well as a fine heterogeneous lamellar transformation microstructure, which is very different to that seen standard wrought products. This arises because of the intrinsic lack of constitutional undercooling at the solidification front, and the subsequent high cooling rates and rapid thermal cycling experienced by the deposited material. In this work, the more refined primary β-grain solidification structures and textures seen in components built with the novel coaxial electron beam wire DED AM (CEWAM) process have been characterised in detail, for the first time, with the aim of investigating the potential for this technology to directly replicate the β-annealed damage-tolerant microstructure used in large Ti64 aerospace forgings. Due to its different lower energy density solidification conditions, it has been confirmed, by electron backscatter diffraction (EBSD) analysis and β-grain reconstruction in three orthogonal cross-sections, that the CEWAM process changes the melt conditions to promote β-grain nucleation ahead of the solidification front, which can result in a highly refined, equiaxed, β-grain structure. However, the conditions for refinement were marginal and a mixed grain structure was commonly observed in thicker sections. Additionally, the subsequent grain-growth stability during β-annealing was investigated. It is shown that an equivalent microstructure can be achieved to that seen in a standard β-forged component, by grain structure homogenisation and slow cooling through the β transus, to promote α colony nucleation, allowing direct part substitution. This was made possible by the refined primary β-grain structure achieved during deposition with the CEWAM solidification conditions which, importantly, are also shown to lead to a weaker texture than in a typical forging
Building Human Renal Tracts
No full textSevere kidney failure affects several million people worldwide. Among these arechildren born with abnormal renal tracts, and some carry mutations of genes active inrenal tract development. Kidney transplants are in short supply, and long-term dialysisdoes not obviate uraemia and its associated harmful effects. It has been evisaged thata combination of stem cell technology, developmental biology, and genetics willrevolutionise our understanding of kidney disease and provide novel therapies forkidney failure. Here, we review progress towards making functional kidney tissues fromhuman pluripotent stem cells. Organoids rich in immature glomeruli and tubules can becreated in culture from pluripotent stem cells. Moreover, differentiation can beincreased by implanting these cells into immunodeficient mice. Challenges remain tobe overcome, however, before these tissues can be used for regenerative medicinetherapies. Current limitations include the small size of an organoid, the lack of largeblood vessels feeding it, and the lack of a urinary tract to plumb the kidney organoid.Pluripotent stem cell technology is also being used to create 'diseases in a dish' tounderstand the pathobiology underlying human renal tract malformations
Equations in virtually abelian groups: Languages and growth
No full textThis paper explores the nature of the solution sets of systems of equations in virtually abelian groups. We view this question from two angles. From a formal language perspective, we prove that the set of solutions to a system of equations forms an EDT0L language, with respect to a natural normal form. Looking at growth, we show that the growth series of the language of solutions is rational. Furthermore, considering the set of solutions as a set of tuples of group elements, we show that it has rational relative growth series with respect to any finite generating set.</p
Psychologists as Leaders in Equitable Science: Applications of Anti-Racism and Community Participatory Strategies in a Pediatric Behavioral Medicine Clinical Trial
No full textDesign and implementation of net zero displacement filter for the synthesis of a mechanical shock signal under specified shock response spectrum
No full textFibrolamellar Carcinoma: challenging the challenge
No full textFibrolamellar Carcinoma (FLC) is a rare and poorly-understood malignancy, which seems to be more prevalent in young patients compared to conventional HCC. Performing prospective clinical trials recruiting patients diagnosed with FLC has proven challenging with scarce data available guiding clinical management. The use of a number of chemotherapy compounds in these patients, including cisplatin, epirubicin, 5-fluorouracil (5-FU), and recombinant interferon alpha-2B (IFN-alpha-2B) have been reported in the literature, mainly in the form of case reports. The most promising systemic therapy tested so far is the combination of 5-FU infusion and 3-weekly IFN-alpha-2B, based on results from a phase II clinical trial. This article provides an overview of our own experience with this treatment schedule for patients with FLC, confirming its activity and treatment-derived benefit in the real world. Current challenges being faced by health care professionals treating patients with advanced FLC are discussed, especially the increasingly limited access to IFN-alpha-2B, which could compromise the access to an active therapy in the coming future, and the difficulties in the development of new treatment options for advanced FLC
