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Conceptualising the impact of information asymmetry on through-life cost: case study of machine tools sector
Information asymmetry (IA) in terms of contextual variety and importance is one of the most challenging aspects of through-life costing in product-service systems (PSS). IA is an imbalance in the information, data and knowledge shared among the parties involved in a contractual agreement. In manufacturing systems under PSS, interaction and effective communication among several parties who are involved in a contractual agreement, rely on the continuity and accuracy of information and context. In such systems, contextual variety exhibits complexity and uncertainty in through-life costing and subsequently in PSS cost assessment. Although the economic aspect of PSS has been studied previously, the impact of IA on through-life cost and for different PSS solutions has not been detailed. Considering manufacturing value chains, this paper introduces a new concept of PSS-hierarchy to perform through-life costing in the presence of IA for various PSS solutions. Moreover, this paper proposes a generic life-cycle model for different PSS solutions to assess the total cost of ownership (TCO). The proposed model has been developed to support decisions on contract design in manufacturing systems. This study considers the manufacturer, service provider and customer perspectives to develop the TCO model using a machine tool manufacturing case study
Modeling of premixing-prevaporizing fuel-air mixing passages
The development of a computer program for the analytical prediction of the distribution of liquid and vapor fuel in the premixing-prevaporizing passage by the direct injection method is described. The technical approach adopted for this program is to separate the problem into three parts each with its own computer code. These three parts are: calculation of the two-dimensional or axisymmetric air flow; calculation of the three-dimensional fuel droplet evaporation; and calculation of the fuel vapor diffusion. This method of approach is justified because premixing passages operate at lean equivalence ratios. Hence, a weak interaction assumption can be made wherein the airflow can affect the fuel droplet behavior but the fuel droplet behavior does not affect the airflow
Domains of invasion organelle proteins from apicomplexan parasites are homologous with the Apple domains of blood coagulation factor XI and plasma pre-kallikrein and are members of the PAN module superfamily
AbstractMicronemes are specialised organelles, found in all apicomplexan parasites, which secrete molecules that are essential for parasite attachment to and invasion of host cells. Regions of several microneme proteins have sequence similarity to the Apple domains (A-domains) of blood coagulation factor XI (FXI) and plasma pre-kallikrein (PK). We have used mass spectrometry on a recombinant-expressed, putative A-domain from the microneme protein EtMIC5 from Eimeria tenella, to demonstrate that three intramolecular disulphide bridges are formed. These bridges are analogous to those that stabilise A-domains in FXI and PK. The data confirm that the apicomplexan domains are structural homologues of A-domains and are therefore novel members of the PAN module superfamily, which also includes the N-terminal domains of members of the plasminogen/hepatocyte growth factor family. The role of A-domains/PAN modules in apicomplexan parasites is not known, but their presence in the microneme suggests that they may be important for mediating protein–protein or protein–carbohydrate interactions during parasite attachment and host cell invasion
Analytical modeling of operating characteristics of premixing-prevaporizing fuel-air mixing passages. Volume 2: User's manual
A user's manual describing the operation of three computer codes (ADD code, PTRAK code, and VAPDIF code) is presented. The general features of the computer codes, the input/output formats, run streams, and sample input cases are described
Development of a Protocol to Manage Postdural Puncture Headache
In obstetric laboring patients, neuraxial anesthesia is a common form of analgesia. However, neuraxial procedures are not without risk. Accidental dural puncture (ADP) is a potential risk with any epidural procedure. Patients who experience ADP are at a greater risk of developing postdural puncture headache (PDPH). The presentation of PDPH is commonly described as a dull, throbbing, headache worsening upon standing and relieved with supine positioning (Patel et al., 2020). Symptoms of PDPH may range from mild to debilitating and develop within five days of ADP. A variety of treatment options exist for PDPH ranging from conservative to invasive. The purpose of this project was to introduce a standardized evidence-based treatment protocol for patients suffering from PDPH. A comprehensive review of the literature revealed the most recent evidence on contributing factors, prevention, and treatment of PDPH. The project study design utilized a non-experimental pre and post-evaluation method completed by nine anesthesia providers. The post-evaluation was collected following the educational PowerPoint presentation to analyze knowledge gained. Overall participants improved their rates of correct responses. Thus, implementation of the PDPH algorithm was directed at improving patient outcomes and enhancing provider knowledge
Mutations of penicillin acylase residue B71 extend substrate specificity by decreasing steric constraints for substrate binding
Two mutant forms of penicillin acylase from Escherichia coli strains, selected using directed evolution for the ability to use glutaryl-L-leucine for growth [Forney, Wong and Ferber (1989) Appl. Environ. Microbiol. 55, 2550-2555], are changed within one codon, replacing the B-chain residue Phe(B71) with either Cys or Leu. Increases of up to a factor of ten in k(cat)/K-m values for substrates possessing a phenylacetyl leaving group are consistent with a decrease in K-s. Values of k(cat/)K(m) for glutaryl-L-leucine are increased at least 100-fold. A decrease in k(cat)/K-m for the CySB71 mutant with increased pH is consistent with binding of the uncharged glutaryl group. The mutant proteins are more resistant to urea denaturation monitored by protein fluorescence, to inactivation in the presence of substrate either in the presence of urea or at high pH, and to heat inactivation. The crystal structure of the Leu(B71) mutant protein, solved to 2 X resolution, shows a flip of the side chain of Phe(B256) into the periphery of the catalytic centre, associated with loss of the pi-stacking interactions between Phe(B256) and Phe(B71). Molecular modelling demonstrates that glutaryl-L-leucine may bind with the uncharged glutaryl group in the S-1 subsite of either the wild-type or the Leu(B71) mutant but with greater potential freedom of rotation of the substrate leucine moiety in the complex with the mutant protein. This implies a smaller decrease in the conformational entropy of the substrate on binding to the mutant proteins and consequently greater catalytic activity
Evidence for Multiple Cycles of Strand Invasion During Repair of Double-Strand Gaps in Drosophila
DNA double-strand breaks (DSBs), a major source of genome instability, are often repaired through homologous recombination pathways. Models for these pathways have been proposed, but the precise mechanisms and the rules governing their use remain unclear. In Drosophila, the synthesis-dependent strand annealing (SDSA) model can explain most DSB repair. To investigate SDSA, we induced DSBs by excision of a P element from the male X chromosome, which produces a 14-kb gap relative to the sister chromatid. In wild-type males, repair synthesis tracts are usually long, resulting in frequent restoration of the P element. However, repair synthesis is often incomplete, resulting in internally deleted P elements. We examined the effects of mutations in spn-A, which encodes the Drosophila Rad51 ortholog. As expected, there is little or no repair synthesis in homozygous spn-A mutants after P excision. However, heterozygosity for spn-A mutations also resulted in dramatic reductions in the lengths of repair synthesis tracts. These findings support a model in which repair DNA synthesis is not highly processive. We discuss a model wherein repair of a double-strand gap requires multiple cycles of strand invasion, synthesis, and dissociation of the nascent strand. After dissociation, the nascent strand may anneal to a complementary single strand, reinvade a template to be extended by additional synthesis, or undergo end joining. This model can explain aborted SDSA repair events and the prevalence of internally deleted transposable elements in genomes
The development of social skills in upper elementary students
This study is designed to determine if a structured approach to the development of social skills, given to students in a Self Contained with Integration (SCI) Classroom, will increase proficiency in these skills. In the study, students in a SCI room will receive instruction in six specific social skills. These skills involve appropriate behaviors in getting along with others. The students will be introduced to individual social skills, practice with the skills, and review each skill, Each skill will be assessed by the homeroom teacher as to gains made in developing appropriate social skills
Evaluating Moodle In Undergraduate Obstetrics and Gynaecology.
‘Medical education is a national strategic asset that reflects well on the country, attracts the brightest and best school leavers from home and abroad and caters for our health needs. We have not, alas, looked after medical education in a manner that allows us to reassure the public that all is well.’ Irish Medical Council, 2003
In 1989, Tim Berners-Lee invented the World Wide Web, and within 10 years it had become a valuable learning resource for the field of medicine. With the aim of improving the undergraduate student experience, educators have experimented with a variety of information technologies for the delivery of medical education. Web 2.0 is helping students to ascertain their learning goals effectively.
Little evidence is available for the implementation of Moodle, a virtual learning environment, into an undergraduate obstetrics and gynaecology curriculum. This thesis demonstrates the integration of Moodle into the course, and the added value as it developed. Moodle was used to deliver a comprehensive online undergraduate curriculum in obstetrics and gynecology, in a multi-site Irish medical school setting in order to optimize clinical exposure for students. There is a paucity of evidence on reliably identifying medical students who are academically underperforming prior to high stakes examinations. Moodle has consistently demonstrated the ability to identify these struggling students
This body of work informs and empowers educators and students to develop their teaching and learning. This thesis provides a point from which future work may examine the learning styles and behaviors of underperforming students with a view to effective remediation. The implementation and evaluation of Moodle was deemed not to require formal Ethics Board approval
Understanding the role of sexual transmission in the spread of ZIKA virus using an individual-based interconnected population model
Citation: Tanver, F., Lee, C., Mcvey, D., & Scoglio, S. (2018). Understanding the role of sexual transmission in the spread of ZIKA virus using an individual-based interconnected population model. Pre-Print, Unpublished Manuscript.Zika virus has affected the world as a long-term threat. Modeling its transmission is important in order to facilitate forecasts and control measures. We propose a novel node-based interconnected population model to simulate both vectored and sexual transmission of Zika virus. Using a sexual contact network, we incorporate heterogeneous mixing in the host population with stochastic transmission for realistic predictions. We also incorporate climatic variations in our model, which affect the mosquito vector population and consequently the arbovirus transmission. We perform extensive simulations to understand the effects of sexual transmission rate and network topology on the spreading of infections. Sexual transmission contributes to the epidemic spread and under certain conditions, can sustain it up to several months without vectors. This can potentially lead to recurrences once the mosquitoes overwinter. We also find that sexual transmission can have a stronger effect when vectored transmission is relatively weaker due to climatic conditions. Our results show that vectored and sexual transmission affect the disease dynamics differently
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