Application of the Theory of Organized Activity to the Coordination of Social Information Systems

Co-ordination is seen as a fundamental aspect of organisational activity where computers can help. This is motivated by the need to reconcile the conflicts that arise from the division of labour that characterises any organisational structure and that is present in almost all business processes. We discuss the main approaches that have been proposed to address this problem and present the Theory of Organized Activity as an alternative approach. This approach, unlike most of the other computer-based approaches to coordination, focuses on the human side of activity support and sees the computer as a tool for organizing human activities instead of a way to automate these activities. In our research we have confirmed that this theory can be applied to several organisational structures, and can be used for the analysis and design of information systems that support coordination of human social activities using information technology. An example of application to the coordination of e-learning activities is provided

A certain class of Laplace transforms with applications to reaction and reaction-diffusion equations

A class of Laplace transforms is examined to show that particular cases of this class are associated with production-destruction and reaction-diffusion problems in physics, study of differences of independently distributed random variables and the concept of Laplacianness in statistics, alpha-Laplace and Mittag-Leffler stochastic processes, the concepts of infinite divisibility and geometric infinite divisibility problems in probability theory and certain fractional integrals and fractional derivatives. A number of applications are pointed out with special reference to solutions of fractional reaction and reaction-diffusion equations and their generalizations.Comment: LaTeX, 12 pages, corrected typo

Perceptions of undergraduate dental students at Makerere College of Health Sciences, Kampala, Uganda towards patient record keeping

BACKGROUND. The creating, maintenance and storage of patients’ medical records is an important competence for the professional training of a dental student. OBJECTIVE. Owing to the unsatisfactory state of dental records at the students’ clinic, the objective of this study was to obtain information from undergraduate dental students on the factors that affect this process and elicit recommendations for improvement. METHODS. This qualitative cross-sectional study used focus group discussions with 4th- and 5th-year dental students for data collection. Data were captured through a written transcript and an audio recorder. The data were transcribed and analysed manually through developing themes, which were compared with the literature and interpreted. RESULTS. Three themes emerged: (i) Poorly designed clerking forms. The clerking forms were deemed to have a poor design with inadequate space for clinical notes. It was recommended that they be redesigned. (ii) Inadequate storage space. Space for storing patient records was deemed inadequate and a referencing system for file retrieval was lacking. It was recommended that more space be allocated for storage, with a referencing system for easy file retrieval. (iii) Poor maintenance of records. Patients’ records, especially radiographs, were not well labelled and stored. It was recommended that drug envelopes be utilised to store radiographs. An electronic system was deemed the ultimate solution to this problem. CONCLUSION. The general perception was that the current paper-based record system at the clinic was unsatisfactory. Therefore, there is a need to improve the maintenance and storage of records, and to change to a more efficient electronic system. The students’ attitude towards record keeping was found to be questionable, with a need to be addressed as part of teaching and learning in the curriculum. Lecturers were deemed to have a bigger role to play in the record-keeping process.DHE

Decay of flux vacua to nothing

We construct instanton solutions describing the decay of flux compactifications of a $6d$ gauge theory by generalizing the Kaluza-Klein bubble of nothing. The surface of the bubble is described by a smooth magnetically charged solitonic brane whose asymptotic flux is precisely that responsible for stabilizing the 4d compactification. We describe several instances of bubble geometries for the various vacua occurring in a $6d$ Einstein-Maxwell theory namely, AdS_4 x S^2, R^{1,3} x S^2, and dS_4 x S^2. Unlike conventional solutions, the bubbles of nothing introduced here occur where a {\em two}-sphere compactification manifold homogeneously degenerates.Comment: 31 pages, 15 figure

Tracing the Cadomian magmatism with detrital/inherited zircon ages by in-situ U–Pb SHRIMP geochronology (Ossa-Morena Zone, SW Iberian Massif),

U–Pb SHRIMP geochronology on zircon extracted from a granite, a sandstone and a quartzite of the SW Iberian Massif (Ossa-Morena Zone), was used in order to investigate the contribution of Late Neoproterozoic (Cadomian) tectonothermal history to the crustal growth of northern Gondwana. The analysed Cambrian rocks were sampled along the southern margin of the Coimbra–Cordoba shear zone (Barquete granite and Crato sandstone), and within this shear zone (Ouguela quartzite). The Barquete granite yielded a crystallization age of 526±4 Ma and evidence for Neoproterozoic and Paleoproterozoic inherited ages. The geochemical signature of the Barquete granite matches the igneous activity of the initial magmatic flooding of the Ossa-Morena Zone during the Early Cambrian. The petrography and geochemical signature of the Crato and Ouguela sandstones indicate that these clastic rocks were mainly derived from felsic igneous rocks. The youngest detrital zircon grain extracted from the Crato sandstone, dated at 552.7±5.5 Ma, has a zircon overgrowth that yielded 532±5.6 Ma. In the Ouguela quartzite, the youngest concordant age yielded 556.4±5.7 Ma, but we also found a zircon overgrowth dated at 536.2±5.6 Ma. The ages of the youngest detrital zircon in each sedimentary rock place an upper limit on the deposition age of Early Cambrian (c. 536– 532 Ma). Four main Late Neoproterozoic age clusters at c. 640–638 Ma, c. 612–613 Ma, c. 590–585 Ma and c. 560 Ma were recognized in the populations of detrital zircons from both sandstones. These ages of zirconforming events seem to represent four successive thermal/magmatic pulses that overlap the Cadomian and Pan-African orogenies. These findings match other results published for the OMZ. Our U–Pb results show that detrital zircons in siliciclastic sediments and inherited zircon in granites are dominated by Neoproterozoic ages and few Paleoproterozoic and Archean ages. Those ages reported in the Ossa-Morena Zone rocks, together with a remarkable lack of Mesoproterozoic ages suggest that the clastic rocks in this peri-Gondwana basin were derived from the West African craton. The large population of Late Cryogenian and Ediacaran ages indicates denudation of the Cadomian basement during the Early Cambrian. A potential source for the detrital and inherited zircons found in this study is a long-lived magmatic arc that is only partly exposed in the SW Iberian Massif but is well represented in other peri-Gondwana regions. The large amount of Cadomian ages obtained in this study (c. 640–560 Ma) reinforces the idea that Cadomian magmatism played a significant role in the continental crustal growth history of Late Neoproterozoic uplift and erosion in Western and Central Europe (Cadomia)

Optimal management of reactive power sources in far-offshore wind power plants

This paper introduces a new approach for the optimal management of reactive power sources, which follows a predictive optimization scheme (i.e. day-ahead, intraday application). Predictive optimization is based to the principle of minimizing the real power losses, as well the number of On-load Tap Changer (OLTC) operations for 24 time steps ahead. The mixed-integer nature of the problem and the restricted computing budget is tackled by using an emerging metaheuristic algorithm called Mean-Variance Mapping Optimization (MVMO). The evolutionary mechanism of MVMO is enhanced by introducing a new mapping function, which improves its global search capability. The effectiveness of MVMO (i.e. fast convergence and robustness against randomness in initialization and factors used in evolutionary operations) and the achievement of optimal grid code compliance are demonstrated by investigating the case of a far-offshore wind power plant, interconnected with HVDC link

Self-Reported Sexual Function in Sexually Active Male Hodgkin Lymphoma Survivors

Introduction: Unambiguous data on sexual dysfunction after Hodgkin lymphoma (HL) treatment are scarce. Aims: To form a baseline in this area, we compared patient-reported sexual function in sexually active male HL survivors in complete remission with a sexually active, age-matched, male Dutch sample population. Furthermore, we explored whether sociodemographic and clinical factors were associated with sexual dysfunction in HL survivors and investigated whether reporting to perceive sexual problems was indicative for sexual dysfunction. Methods: This cross-sectional study included male patients with HL who were treated with chemotherapy and age-matched sexually active males. Main outcome measures: Outcome measures included the internationally validated International Index of Erectile Function (IIEF) and self-reported sexual problems by adding 3 items to the study-specific questionnaire. Results: Erectile dysfunction (ED) occurred in 23.3% of the HL survivors vs in 23.0% of controls: respectively 13.3% and 12.3% had moderate to severe ED. However, more HL survivors positively answered the question whether they did perceive sexual problems than controls (20.0% vs 7.0%; P ¼ .087). More patients treated with bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procabazine, and prednisone (BEACOPP) had sexual problems 33.3% vs 8.3% who were treated with doxorubicin, bleomycin, vinblastine, and dacarbazine (P ¼ .057). Importantly, we found that the mean IIEF score for erectile function was 15.7 in HL survivors who reported to perceive sexual problems (moderate ED) vs 28.3 (normal) in those without perceiving sexual problems. Conclusion: In general, sexual function of male HL survivors is comparable to that of matched normal cont