An Intelligent Synthetic Bacterium for Chronological Toxicant Detection, Biodegradation, and Its Subsequent Suicide.

Modules, toolboxes, and synthetic biology systems may be designed to address environmental bioremediation. However, weak and decentralized functional modules require complex control. To address this issue, an integrated system for toxicant detection and biodegradation, and subsequent suicide in chronological order without exogenous inducers is constructed. Salicylic acid, a typical pollutant in industrial wastewater, is selected as an example to demonstrate this design. Biosensors are optimized by regulating the expression of receptors and reporters to get 2-fold sensitivity and 6-fold maximum output. Several stationary phase promoters are compared, and promoter Pfic is chosen to express the degradation enzyme. Two concepts for suicide circuits are developed, with the toxin/antitoxin circuit showing potent lethality. The three modules are coupled in a stepwise manner. Detection and biodegradation, and suicide are sequentially completed with partial attenuation compared to pre-integration, except for biodegradation, being improved by the replacements of ribosome binding site. Finally, a long-term stability test reveals that the engineered strain maintained its function for ten generations. The study provides a novel concept for integrating and controlling functional modules that can accelerate the transition of synthetic biology from conceptual to practical applications.

Order matters: Alphabetizing in-text citations biases citation rates.

Though citations are critical for communicating science and evaluating scholarly success, properties unrelated to the quality of the work-such as cognitive biases-can influence citation decisions. The primacy effect, in particular, is relevant to lists, which for in-text citations could result in citations earlier in the list receiving more attention than those later in the list. Therefore, how citations are ordered could influence which citations receive the most attention. Using a sample of 150,000 articles, we tested whether alphabetizing in-text citations biases readers into citing more often articles with first authors whose surnames begin with letters early in the alphabet. We found that surnames earlier in the alphabet were cited more often than those later in the alphabet when journals ordered citations alphabetically compared with chronologically or numerically. This effect seemed to be stronger in psychology journals (which have a culture of alphabetizing citations) compared with biology or geoscience journals (which primarily order chronologically or numerically) and was strongest among moderately and highly cited articles. Therefore, alphabetizing in-text citations biases citation decisions toward authors with surnames occurring early in the alphabet. These citation decisions result from an interaction between cognitive biases (more attention devoted to items earlier in a list) and the structure of the citation environment (the style in which citations are ordered). We suggest that journals using alphabetically ordered citations switch to chronological ordering to minimize this arbitrary alphabetical citation bias.

Boarding ICU patients: Are our rounding practices subpar?

INTRODUCTION: Surgical Intensive Care Unit (SICU) patients "boarding" in ICUs other than the designated home unit have been shown to suffer increased rates of complications. We hypothesized that ICU rounding practices are different when SICU patients are housed in home vs. boarding ICUs. MATERIAL AND METHODS: SICU rounds were observed at an academic quaternary medical center. Individual patient rounding time and order seen on rounds along with patient data and demographics were recorded. Multivariable regression analysis was used for comparison between patients. RESULTS: Non-boarders were older, observed on a later post ICU admission day and were more likely to be mechanically ventilated. Boarded patients were often seen at the end of rounds and for less time. Not being a boarder, age, APACHE II score on admission, vasopressor use, and positive pressure ventilation all predicted increased rounding time. CONCLUSIONS: Surgical ICU patients boarding in non-preferred units are often seen at the end of rounds, result in a greater reliance upon telephone communication, and receive less bedside attention from ICU provider teams.