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Purpose: Legumes form root nodules to gain fixed nitrogen from rhizobia and can also access nitrogen in soil. Data suggest that plants might discriminate among these sources to optimize growth, but recognition of symbiotically fixed nitrogen and its regulation remain poorly understood. Methods: A greenhouse inoculation study manipulated the molecular form and concentration of nitrogen available using two Lotus japonicus genotypes and the nitrogen-fixing symbiont, Mesorhizobium loti. Plants were supplied with sole organic and inorganic nitrogen sources to simulate forms that plants might receive from symbiotic nitrogen fixation or from the soil. Host benefit from and regulation of symbiosis was investigated by quantifying symbiotic trait variation and isotopic analysis of nitrogen fixation. Results: Host growth varied in response to fertilization with alanine, aspartic acid, ammonium, and nitrate, suggesting differences in catabolism efficiency. Net benefits of nodulation were reduced or eliminated under all forms of extrinsic fertilization. However, even when symbiosis imposed significant costs, hosts did not reduce investment into nodulation or nitrogen fixation when exposed to aspartic acid, unlike with other nitrogen sources. Conclusions: L. japonicus can adaptively downregulate investment into symbiosis in the presence of some but not all nitrogen sources. Failure to downregulate any aspect of symbiosis in the presence of aspartic acid suggests that it might be jamming the main signal used by L. japonicus to detect nitrogen fixation.

Purpose: Crops rely on microbes for critical services, but host benefits can be influenced by local makeup of microbiota and the host’s capacity to select optimal strains. We investigated host benefits that cowpeas receive from microbiota depending on plant genotype, their domestication status, and soil source. Methods: We performed a full factorial soil inoculation experiment. Twenty diverse cowpea genotypes, selected from wild and domesticated populations, were exposed to soil rinsates from four agricultural sites across California, all having cowpea cultivation and varied physicochemical features. Cowpea investment in and benefit from microbiota was quantified by measuring host growth response to inoculation, nodulation, and segregating trait variation. Results: Variation in induction of root nodulation and strikingly heterogenous benefits to host growth were observed among soil sites. These effects were restricted to live soil inocula but were absent in autoclaved soil controls that lacked microbiota. Cowpeas expressed heritable variation in nodulation, but there was negligible effect of plant population or domestication status on the net benefit that hosts gained from microbiota. Conclusion: Soils varied substantially and consistently among cultivation sites and were the most prominent driver shaping host growth effects on cowpeas. While growth benefits vary among host cultivars, soil microbiota (and the conditions that maintain them) predominantly shape plant performance in agricultural settings.

To assess the incidence and preventability of adverse drug events in the ambulatory setting, we performed a study of persons aged 65 or older cared for by a multispecialty group practice over a one-year period. Potential drug-related incidents were detected through various approaches including review of hospital discharges, review of emergency room notes, reports of healthcare providers, computer-generated signals, and automated review of electronic clinic notes. Medical record reviews were performed by clinical pharmacists, with subsequent classification of incidents by physician reviewers. Over 31,757 person-years of observation, 1530 adverse drug events were identified for an event rate of 48.2 per 1000 person years. Errors resulting in preventable adverse drug events occurred most often at the stages of monitoring, prescribing, and patient adherence. Overall, 28% of adverse drug events were judged preventable. We conclude that adverse drug events are common and often preventable among elderly patients in the ambulatory setting.

Purpose: To examine the process by which nurses recovered medical errors and to obtain item statements for a survey to quantify nurses' contributions to patient safety. Background/Significance: As frontline caregivers, [...]

While exploring the diversity of women's work experiences, this study determined which factors were associated with retaining staff nurses. Findings reaffirm the importance of understanding women's relationships to their work through a personal and a professional context. Results suggest that the emphasis placed on working conditions and professional and fringe benefits vary according to three distinct life-cycle changes. [ABSTRACT FROM AUTHOR]

A second look at AJN's Patient Care Survey identifies trends in health care that strongly influenced readers' ratings of the institutions where they work. See how yours measures up. [ABSTRACT FROM AUTHOR]

We all know the changes in our health care system have been substantial and far-reaching. But what effects are downsizing, restructuring, and the use of unlicensed personnel having on the quality of patient care you deliver and on your work life? More than 7,000 survey respondents gave us their answers. [ABSTRACT FROM AUTHOR]