How often do physicians review medication charts on ward rounds?

Background  

Prescribing errors are common in hospital settings. Regular review of medication charts is recommended as a way to reduce errors but it is not clear how often this happens. The aim of this study was to determine the frequency with which specialist physicians reviewed medication charts during ward rounds.     

A simple formula useful for positional cloning.

We derive a formula for the distribution of the length T of the recombination interval containing a target gene and using N gametes in a region where R kilobases correspond to 1 cM. The formula can be used to calculate the number of meiotic events required to narrow a target gene down to a specific interval size and hence should be useful for planning positional cloning experiments. The predictions of this formula agree well with the results from a number of published experiments in Arabidopsis.     

Dr. Lucid's word rounds.

Between Oct. 1, 1983, and June 30, 1985, Cryptosporidium oocysts were identified in stool specimens from 74 patients who presented with gastrointestinal symptoms to their physicians. Questionnaires prepared to determine travel history, symptoms, duration of illness and epidemiologic characteristics of the infection were completed for 67 (90%) of the patients by their physicians; the information on the other 7 patients was obtained from the requisitions accompanying the specimens. Of the 67, 35 (52%) had recently been to Mexico. The infection was likely transmitted through contaminated water, food and, possibly, milk. The infections in patients who had not travelled were thought to be due to contact with infected pets or farm animals or with infected children attending daycare centres. Diarrhea, vomiting, fever and nausea usually lasted for 1 to 2 weeks, except in those with immune deficiency, in whom the symptoms persisted for up to 6 months. The condition was diagnosed by identification of oocysts in stool specimens that underwent formalin-ether sedimentation and modified cold Kinyoun staining.     

Trauma rounds: Orthopedic emergencies.

To determine how adequately patients who participate as subjects for clinical investigation understand their commitment, 50 patients admitted to the Clinical Research Center of the University of Washington were interviewed. Their responses were compared with the detailed statements in the consent forms for the 23 specific protocols under which they were being studied. In spite of careful controls in accord with guidelines of a review committee, only half the patients were able to describe accurately their expectations of the studies to which they had given signed consent.     

An adolescent ward.

A ward has been set up for adolescents, who, being neither children nor adults, have special needs. It provides a pleasant and enthusiastic atmosphere that allows the patients to mix together socially alties is important, but not more than 20% should be long-stay patients. Those needing intensive care or specialised investigations and those likely to be a disruptive influence are excluded. No serious sexual problems have been encountered.     

Optimal sequencing by hybridization in rounds.

Sequencing by hybridization (SBH) is a method for sequencing DNA. The Watson-Crick complementarity of DNA can be used to determine whether the DNA contains an oligonucleotide substring. A large number of oligonucleotides can be arranged on an array (SBH chip). A combinatorial method is used to construct the sequence from the collection of probes that occur in it. We develop an idea of Margaritis and Skiena and propose an algorithm that uses a series of small SBH chips to sequence long strings. The total number of probes used by our method matches the information theoretical lower bound up to a constant factor.     

A new formula for estimating oxygen consumption in man and animal.

A formula for estimating oxygen consumption in man and animals using outlet volume flow and oxygen fraction of CO2-free outlet air is derived. The formula is simplified and the error induced is evaluated. Two applications are discussed.     

A new interpolation formula for semiflexible polymers

A new formula for the force vs. extension relation is derived from the discrete version of the so-called Worm-like chain model. This formula correctly fits some recent experimental data on polymer stretching. Moreover, we have compared our formula with a Monte Carlo simulation of a semiflexible polymer.     

A new Euler's formula for DNA polyhedra

DNA polyhedra are cage-like architectures based on interlocked and interlinked DNA strands. We propose a formula which unites the basic features of these entangled structures. It is based on the transformation of the DNA polyhedral links into Seifert surfaces, which removes all knots. The numbers of components μ, of crossings c, and of Seifert circles s are related by a simple and elegant formula: s + μ = c + 2. This formula connects the topological aspects of the DNA cage to the Euler characteristic of the underlying polyhedron. It implies that Seifert circles can be used as effective topological indices to describe polyhedral links. Our study demonstrates that, the new Euler's formula provides a theoretical framework for the stereo-chemistry of DNA polyhedra, which can characterize enzymatic transformations of DNA and be used to characterize and design novel cages with higher genus.     

A new sampling formula for neutral biodiversity

The neutral model of biodiversity, proposed by Hubbell (The Unified Neutral Theory of Biodiversity and Biogeography, Princeton University Press, Princeton, NJ, 2001) to explain the diversity of functionally equivalent species, has been subject of hot debate in community ecology. Whereas Hubbell studied the model mostly by simulations, recently analytical treatments have yielded expressions of the expected number of species of a particular abundance in a local community with dispersal limitation. Moreover, a formula has been offered for the joint likelihood of observing a given species‐abundance dataset in a local community with dispersal limitation, but this formula is too complicated to allow practical applications. Here, I present a much simplified expression that can be regarded as an enhanced version of the famous Ewens sampling formula. It can be used in maximum likelihood methods for quick estimation of the model parameters, using all information in the data, and for model comparison. I also show how to rapidly generate examples of species‐abundance distributions for a given set of model parameters and how to calculate Simpson's diversity index.