A GENERALIZATION OF A PROBLEM OF STUPARU

Let n be a composite integer >= 48. Prove that between nand S(n) there exist at least 5 prime numbers

Human factors tools for improving simulation activities in continuing medical education

Human factors (HF) is a discipline often drawn upon when there is a need to train people to perform complex, high‐stakes tasks and effectively assess their performance. Complex tasks often present unique challenges for training and assessment. HF has developed specialized techniques that have been effective in overcoming several of these challenges in work settings such as aviation, process control, and the military. Many HF techniques could be applied to simulation in continuing medical education to enhance effectiveness of simulation and training, yet these techniques are not widely known by medical educators. Three HF techniques are described that could benefit health care simulation in areas of training techniques, assessment, and task design: (1) bandwidth feedback techniques for designing better feedback and task guidance, (2) dual‐task assessment techniques that can differentiate levels of expertise in tasks where performance is essentially perfect, and (3) task abstraction techniques for developing task‐relevant fidelity for simulations. Examples of each technique are given from work settings in which these principles have been applied successfully. Application of these principles to medical simulation and medical education is discussed. Adapting these techniques to health care could improve training in medical education.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95199/1/21154_ftp.pd

The effects of cytochalasins on onion seedling growth and development and their possible mode of action.

Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1975 .S42. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.Sc.)--University of Windsor (Canada), 1975

Plasticity of the cis-Regulatory Input Function of a Gene

The transcription rate of a gene is often controlled by several regulators that bind specific sites in the gene's cis-regulatory region. The combined effect of these regulators is described by a cis-regulatory input function. What determines the form of an input function, and how variable is it with respect to mutations? To address this, we employ the well-characterized lac operon of Escherichia coli, which has an elaborate input function, intermediate between Boolean AND-gate and OR-gate logic. We mapped in detail the input function of 12 variants of the lac promoter, each with different point mutations in the regulator binding sites, by means of accurate expression measurements from living cells. We find that even a few mutations can significantly change the input function, resulting in functions that resemble Pure AND gates, OR gates, or single-input switches. Other types of gates were not found. The variant input functions can be described in a unified manner by a mathematical model. The model also lets us predict which functions cannot be reached by point mutations. The input function that we studied thus appears to be plastic, in the sense that many of the mutations do not ruin the regulation completely but rather result in new ways to integrate the inputs

Evaluation of a simulation‐based curriculum for implementing a new clinical protocol

ObjectiveTo evaluate the implementation of a new clinical protocol utilizing on‐unit simulation for team training.MethodsA prospective observational study was performed at the obstetrics unit of Von Voightlander Women’s Hospital, Michigan, USA, between October 1, 2012 to April 30, 2013. All members of the labor and delivery team were eligible for participation. Traditional education methods and in‐situ multi‐disciplinary simulations were used to educate labor and delivery staff. Following each simulation, participants responded to a survey regarding their experience. To evaluate the effect of the interventions, paging content was analyzed for mandated elements and adherence to operating room entry‐time tracking was examined.ResultsIn total, 51 unique individuals participated in 12 simulations during a 6‐month period. Simulation was perceived as a valuable activity and paging content improved. Following the intervention, the inclusion of a goal time for reaching the operation room increased from 7% to 61% of pages and the proportion of patients entering to operating room within 10 minutes of the stated goal increased from 67% to 85%.ConclusionThe training program was well received, and the accuracy of the communication and the goal set for reaching the operating room improved.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135397/1/ijgo333.pd

Child maltreatment in the "children of the nineties" : a cohort study of risk factors

Aim: To analyze the multiple factors affecting the risk of maltreatment in young children within a comprehensive theoretical framework. Methods: The research is based on a large UK cohort study, the Avon Longitudinal Study of Parents and Children. Out of 14,256 children participating in the study, 293 were investigated by social services for suspected maltreatment and 115 were placed on local child protection registers prior to their 6th birthday. Data on the children have been obtained from obstetric data and from a series of parental questionnaires administered during pregnancy and the first 3 years of life. Risk factors have been analyzed using an hierarchical approach to logistic regression analysis. Results: In the stepwise hierarchical analysis, young parents, those with low educational achievement, and those with a past psychiatric history or a history of childhood abuse were all more likely to be investigated for maltreatment, or to have a child placed on the child protection register, with odds ratios between 1.86 and 4.96 for registration. Examining strength of effect, the highest risks were found with indicators of deprivation (3.24 for investigation and 11.02 for registration, after adjusting for parental background factors). Poor social networks increased the risk of both investigation (adjusted OR 1.93) and registration (adjusted OR 1.90). Maternal employment seemed to reduce the risk of both outcomes but adjusted odds ratios were no longer significant for registration. After adjusting for higher order confounders, single parents and reordered families were both at higher risk of registration. Reported domestic violence increased the risk of investigation and registration but this was no longer significant after adjusting for higher order variables. Low birthweight children were at higher risk of registration as were those whose parents reported few positive attributes of their babies. Conclusions: This study supports previous research in the field demonstrating that a wide range of factors in the parental background, socio-economic and family environments affect the risk of child maltreatment. By combining factors within a comprehensive ecological framework, we have demonstrated that the strongest risks are from socio-economic deprivation and from factors in the parents' own background and that parental background factors are largely, but not entirely, mediated through their impact on socio-economic factors

Gluon mass generation in the PT-BFM scheme

In this article we study the general structure and special properties of the Schwinger-Dyson equation for the gluon propagator constructed with the pinch technique, together with the question of how to obtain infrared finite solutions, associated with the generation of an effective gluon mass. Exploiting the known all-order correspondence between the pinch technique and the background field method, we demonstrate that, contrary to the standard formulation, the non-perturbative gluon self-energy is transverse order-by-order in the dressed loop expansion, and separately for gluonic and ghost contributions. We next present a comprehensive review of several subtle issues relevant to the search of infrared finite solutions, paying particular attention to the role of the seagull graph in enforcing transversality, the necessity of introducing massless poles in the three-gluon vertex, and the incorporation of the correct renormalization group properties. In addition, we present a method for regulating the seagull-type contributions based on dimensional regularization; its applicability depends crucially on the asymptotic behavior of the solutions in the deep ultraviolet, and in particular on the anomalous dimension of the dynamically generated gluon mass. A linearized version of the truncated Schwinger-Dyson equation is derived, using a vertex that satisfies the required Ward identity and contains massless poles belonging to different Lorentz structures. The resulting integral equation is then solved numerically, the infrared and ultraviolet properties of the obtained solutions are examined in detail, and the allowed range for the effective gluon mass is determined. Various open questions and possible connections with different approaches in the literature are discussed.Comment: 54 pages, 24 figure

Actin and microtubules drive differential aspects of planar cell polarity in multiciliated cells

Actin dynamics are required for proper cilia spacing, global coordination of cilia polarity, and coordination of metachronic cilia beating, whereas cytoplasmic microtubule dynamics are required for local coordination of polarity between neighboring cilia