Methods of competing risks analysis of end-stage renal disease and mortality among people with diabetes

<p>Abstract</p> <p>Background</p> <p>When a patient experiences an event other than the one of interest in the study, usually the probability of experiencing the event of interest is altered. By contrast, disease-free survival time analysis by standard methods, such as the Kaplan-Meier method and the standard Cox model, does not distinguish different causes in the presence of competing risks. Alternative approaches use the cumulative incidence estimator by the Cox models on cause-specific and on subdistribution hazards models. We applied cause-specific and subdistribution hazards models to a diabetes dataset with two competing risks (end-stage renal disease (ESRD) or death without ESRD) to measure the relative effects of covariates and cumulative incidence functions.</p> <p>Results</p> <p>In this study, the cumulative incidence curve of the risk of ESRD by the cause-specific hazards model was revealed to be higher than the curves generated by the subdistribution hazards model. However, the cumulative incidence curves of risk of death without ESRD based on those three models were very similar.</p> <p>Conclusions</p> <p>In analysis of competing risk data, it is important to present both the results of the event of interest and the results of competing risks. We recommend using either the cause-specific hazards model or the subdistribution hazards model for a dominant risk. However, for a minor risk, we do not recommend the subdistribution hazards model and a cause-specific hazards model is more appropriate. Focusing the interpretation on one or a few causes and ignoring the other causes is always associated with a risk of overlooking important features which may influence our interpretation.</p

Erratum: Health-related quality of life of antiretroviral treatment defaulters in Botswana

In the publication of the article, the first author’s second affiliation country was published incorrectly as South Africa instead of Canada. This has been corrected under the affiliations sections of the erratum

Chemical homogeneity of wide binary system: An approach from Near-Infrared spectroscopy

Wide binaries, with separations between two stars from a few AU to more than several thousand AU, are valuable objects for various research topics in Galactic astronomy. As the number of newly reported wide binaries continues to increase, studying the chemical abundances of their component stars becomes more important. We conducted high-resolution near-infrared (NIR) spectroscopy for six pairs of wide binary candidates using the Immersion Grating Infrared Spectrometer (IGRINS) at the Gemini-South telescope. One pair was excluded from the wide binary samples due to a significant difference in radial velocity between its component stars, while the remaining five pairs exhibited homogeneous properties in 3D motion and chemical composition among the pair stars. The differences in [Fe/H] ranged from 0.00 to 0.07 dex for these wide binary pairs. The abundance differences between components are comparable to the previous results from optical spectroscopy for other samples. In addition, when combining our data with literature data, it appears that the variation of abundance differences increases in wide binaries with larger separations. However, the SVO2324 and SVO3206 showed minimal differences in most elements despite their large separation, supporting the concept of multiple formation mechanisms depending on each wide binary. This study is the first approach to the chemical properties of wide binaries based on NIR spectroscopy. Our results further highlight that NIR spectroscopy is an effective tool for stellar chemical studies based on equivalent measurements of chemical abundances from the two stars in each wide binary system.Comment: 16 pages, 9 figures, accepted for publication in A

Modeling Solids in Nuclear Astrophysics with Smoothed Particle Hydrodynamics

Smoothed Particle Hydrodynamics (SPH) is a frequently applied tool in computational astrophysics to solve the fluid dynamics equations governing the systems under study. For some problems, for example when involving asteroids and asteroid impacts, the additional inclusion of material strength is necessary in order to accurately describe the dynamics. In compact stars, that is white dwarfs and neutron stars, solid components are also present. Neutron stars have a solid crust which is the strongest material known in nature. However, their dynamical evolution, when modeled via SPH or other computational fluid dynamics codes, is usually described as a purely fluid dynamics problem. Here, we present the first 3D simulations of neutron-star crustal toroidal oscillations including material strength with the Los Alamos National Laboratory SPH code FleCSPH. In the first half of the paper, we present the numerical implementation of solid material modeling together with standard tests. The second half is on the simulation of crustal oscillations in the fundamental toroidal mode. Here, we dedicate a large fraction of the paper to approaches which can suppress numerical noise in the solid. If not minimized, the latter can dominate the crustal motion in the simulations.Comment: 24 pages, 29 figure

An experience on natural sciences augmented reality contents for preschoolers

[EN] Early education is a key element for the future success of students in the education system. This work analyzes the feasibility of using augmented reality contents with preschool students (four and five years old) as a tool for improving their learning process. A quasi experimental design based on a nonequivalent groups posttest-only design was used. A didactic unit has been developed around the topic animals by the participant teachers. The control group followed all the didactic activities defined in the developed didactic materials, while the experimental group was provided in addition with some augmented reality contents. Results show improved learning outcomes in the experimental group with respect to the control group.The Spanish Ministry Economy and Competitiveness partially supported this work (Project ref. TIN2010-21296-C02-01).Cascales, A.; Laguna, I.; Pérez López, DC.; Perona Ruiz, PD.; Contero, M. (2013). An experience on natural sciences augmented reality contents for preschoolers. Lecture Notes in Computer Science. 8022:103-112. https://doi.org/10.1007/978-3-642-39420-1_12S1031128022Barnett, W.S.: Effectiveness of Early Educational Intervention. Science 333(6045), 975–978 (2011)OECD: Investing in high-quality early childhood education and care (ECEC). OECD Publishing, http://www.oecd.org/dataoecd/0/28/48980282.pdf (retrieved)Campos, P., Pessanha, S.: Designing Augmented Reality Tangible Interfaces for Kindergarten Children. In: Shumaker, R. (ed.) Virtual and Mixed Reality, HCII 2011, Part I. LNCS, vol. 6773, pp. 12–19. Springer, Heidelberg (2011)Lim, J., Kim, S.: A Study on Markerless AR-based Infant Education System using CBIR. Communications in Computer and Information Science 78, 52–58 (2010)Chen, C.H., Su, C.C., Lee, P.Y., Wu, F.G.: Augmented Interface for Children Chinese Learning Technologies. In: 7th IEEE International Conference on Advanced Learning Technologies, pp. 268–270. IEEE Press, New York (2007)Azuma, R.: A Survey of Augmented Reality. Presence: Teleoperators and Virtual Environments 6(1), 355–385 (1997)Winkler, T., Herczeg, M., Kritzenberger, H.: Mixed Reality Environments as Collaborative and Constructive Learning Spaces for Elementary School Children. In: Barker, P., Rebelsky, S. (eds.) Proceedings of World Conference on Educational Multimedia, Hypermedia and Telecommunications 2002, pp. 1034–1039. AACE, Chesapeake (2002)Hsieh, M.C., Lee, J.S.: AR Marker Capacity Increasing for Kindergarten English Learning. In: International Multi Conference of Engineers and Computer Scientists, vol. 1, pp. 663–666 (2008)Hsieh, M.C., Lin, H.C.K.: Interaction Design Based on Augmented Reality Technologies for English Vocabulary Learning. In: Wong, S.L., et al. (eds.) Proceedings of the 18th International Conference on Computers in Education, vol. 1, pp. 663–666. Asia-Pacific Society for Computers in Education (2010)Lee, H., Lee, J.: Mathematical Education Game Based on Augmented Reality. Technologies for E-Learning and Digital Entertainment, 442–450 (2008)Hyun, E., Choi, K., Kim, G.J., Han, J., Jo, M., Kim, N.: Delphi Survey on the Use of Robot Projector based Augmented Reality in Dramatic Activity for Young Children. International Journal of Digital Content Technology and its Applications 5(11), 272–282 (2011)Kim, H.M., Song, T.H., Jung, S.M., Kwon, K.H., Jeon, J.W.: Virtual Storyteller Using Marker Based AR and FPGA. In: IEEE 54th International Midwest Symposium on Circuits and Systems, pp. 1–4. IEEE Press, New York (2011)Dunleavy, M., Dede, C., Mitchell, R.: Affordances and Limitations of Immersive Participatory Augmented Reality Simulations for Teaching and Learning. Journal of Science Education and Technology 18, 7–22 (2009)Martín-Gutiérrez, J., Saorín, J.L., Contero, M., Alcañiz, M., Pérez-López, D., Ortega, M.: Design and validation of an augmented book for spatial abilities development in engineering students. Computers & Graphics 34(1), 77–91 (2010)Cook, T.D., Campbell, D.T., Day, A.: Quasi-experimentation: Design and Analysis Issues for Field Settings, pp. 19–21. Houghton Mifflin, Boston (1979)Buendía, L., Colás, P., Hernández-Pina, F.: Métodos de Investigación en Psicopedagogía. McGraw Hill, Madrid (1997

Assessment of mGluR5 KO mice under conditions of low stress using a rodent touchscreen apparatus reveals impaired behavioural flexibility driven by perseverative responses

Genetic and pharmacological manipulations targeting metabotropic glutamate receptor 5 (mGluR5) affect performance in behavioural paradigms that depend on cognitive flexibility. Many of these studies involved exposing mice to highly stressful conditions including electric foot shocks or water immersion and forced swimming. Because mGluR5 is also implicated in resilience and stress responses, however, apparent impairments in inhibitory learning may have been an artifact of manipulation-induced changes in affective state. To address this, we present here a characterization of cognitive flexibility in mGluR5 knockout (KO) mice conducted with a rodent touchscreen cognitive assessment apparatus in which the animals experience significantly less stress. Our results indicate a significant reversal learning impairment relative to wild-type (WT) controls in the two-choice Visual Discrimination-Reversal (VDR) paradigm. Upon further analysis, we found that this deficit is primarily driven by a prolonged period of perseveration in the early phase of reversal. We also observed a similar perseveration phenotype in the KO mice in the Extinction (EXT) paradigm. In addition, mGluR5 KO mice show higher breakpoints in the touchscreen Progressive Ratio (PR) and altered decision making in the Effort-related Choice (ERC) tasks. Interestingly, this impairment in PR is an additional manifestation of an increased propensity to perseverate on the emission of relatively simplistic behavioural outputs. Together, these findings suggest that under conditions of low stress, mGluR5 KO mice exhibit a pronounced perseverative phenotype that blunts cognitive flexibility

Gastric Choristoma of the Oropharynx

Heterotopic gastric mucosa tissue is also called gastric choristoma, and this type of lesion can be found anywhere in the alimentary tract. However, gastric choristoma in the pharynx is very rare; only 10 cases of pharyngeal gastric choristoma have been reported in the English medical literature. A 32-yr-old woman was referred to our institution for the evaluation of a large mass that originated from the posterior wall of the oropharynx. The mass did not cause any symptoms except for the occasional sensation of a foreign body. Gadolinium-enhanced T1 weighted imaging showed a 5 cm-sized mass with central enhancement and hypointense portions, yet the radiological diagnosis was not clear. Transoral mass excision was performed with using electrocautery for making the diagnosis and for treating the mass. The microscopic analysis revealed gastric choristoma

Experiments and failure analysis of SHCC and reinforced concrete composite slabs

For all types of concrete structures, controlling of cracking, as well as the enhancement of serviceability and ultimate flexural capacity are important issues for deck slabs. This study presents an experimental campaign and accompanying nonlinear analysis of a series of Strain Hardening Cementitious Composite (SHCC) and reinforced concrete slab systems, simply-supported and subjected to four-point loading. In order to improve flexural performance both at the service and ultimate limit states, an SHCC layer with thickness of 150–400 mm was placed on the soffit of the composite slab; the SHCC was manufactured using two different processes, namely cast-in-situ SHCCs and extruded precast SHCC panel. Nonlinear analysis of SHCC and reinforced concrete slabs was also carried out to predict moment and curvature as well as deflections of the slab systems. The developed slab systems were found to have enhanced performance with regard to both at serviceability and flexural capacity, compared to the conventional reinforced concrete slab

Focal Bone Marrow Lesions: A Complication of Ultrasound Diathermy

Ultrasound diathermy is widely used for the treatment of musculoskeletal disorders and other soft tissue injuries. Its use as a therapeutic modality is believed to be safe, with very few reported complications. Here, we report two patients who developed focal bone marrow abnormalities after receiving ultrasound diathermy. Both patients’ magnetic resonance (MR) evaluations revealed linear subchondral bone lesions of the superolateral humeral head similar to those in osteonecrosis. The patients’ symptoms subsequently improved, and available follow-up MR evaluation revealed near complete resolution of bone lesions. These findings suggest that ultrasound diathermy, and its interaction with bone tissue through thermal mechanisms, can cause focal bone marrow abnormalities. Furthermore, the bone marrow abnormalities seem to be transient, resolving upon cessation of ultrasound diathermy, therefore osteonecrosis should be differentiated from this temporal lesion