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Purpose: Practice-based Research Networks (PBRNs) have emerged as key laboratories for generating new knowledge that reflects community-based practice; however, the representativeness of nurse practitioners (NPs) interested in PBRN participation is not known. This study describes characteristics of NP members interested in participating in a regional PBRN in comparison with state and national data. Data sources: All 1016 NPs in northeast (NE) Ohio were surveyed by mail and Internet. The survey captured NP demographics, practice characteristics, and gauged interest in participating in future PBRN studies. Survey respondent's data were compared with Ohio and national data obtained from the 2004 AANP National Nurse Practitioner Sample Survey. Conclusions: NE Ohio NPs were similar to an Ohio and national sample of NPs. Northeast Ohio NPs practicing in ambulatory settings who were interested in participating in subsequent PBRN studies were not significantly different from non-interested NPs. Implications for practice: NPs interested in participation in a PBRN appear to be representative of the NE Ohio population of ambulatory practice NPs and are similar demographically to a national sample of NPs. Findings from studies conducted in the NE Ohio PBRN may generalize to other NPs practicing in the region and across the country. [ABSTRACT FROM AUTHOR]

Medium-chain carboxylates (MCCs) are used in various industrial applications. These chemicals are typically extracted from palm oil, which is deemed not sustainable. Recent research has focused on microbial chain elongation using reactors to produce MCCs, such as n -caproate (C6) and n -caprylate (C8), from organic substrates such as wastes. Even though the production of n -caproate is relatively well-characterized, bacteria and metabolic pathways that are responsible for n -caprylate production are not. Here, three 5 L reactors with continuous membrane-based liquid-liquid extraction (i.e., pertraction) were fed ethanol and acetate and operated for an operating period of 234 days with different operating conditions. Metagenomic and metaproteomic analyses were employed. n -Caprylate production rates and reactor microbiomes differed between reactors even when operated similarly due to differences in H 2 and O 2 between the reactors. The complete reverse β-oxidation (RBOX) pathway was present and expressed by several bacterial species in the Clostridia class. Several Oscillibacter spp., including Oscillibacter valericigenes , were positively correlated with n -caprylate production rates, while Clostridium kluyveri was positively correlated with n -caproate production. Pseudoclavibacter caeni , which is a strictly aerobic bacterium, was abundant across all the operating periods, regardless of n -caprylate production rates. This study provides insight into microbiota that are associated with n -caprylate production in open-culture reactors and provides ideas for further work.IMPORTANCEMicrobial chain elongation pathways in open-culture biotechnology systems can be utilized to convert organic waste and industrial side streams into valuable industrial chemicals. Here, we investigated the microbiota and metabolic pathways that produce medium-chain carboxylates (MCCs), including n -caproate (C6) and n -caprylate (C8), in reactors with in-line product extraction. Although the reactors in this study were operated similarly, different microbial communities dominated and were responsible for chain elongation. We found that different microbiota were responsible for n -caproate or n -caprylate production, and this can inform engineers on how to operate the systems better. We also observed which changes in operating conditions steered the production toward and away from n -caprylate, but more work is necessary to ascertain a mechanistic understanding that could be predictive. This study provides pertinent research questions for future work., Competing Interests: L.T.A. has ownership in Capro-X, Inc., which is a start-up company that is commercializing a chain-elongating biotechnology production platform.

New antimicrobial peptides are emerging as promising alternatives to conventional antibiotics because of their specificity for target pathogens and their potential to be rapidly hydrolyzed ( i.e. , inactivated) by extracellular peptidases during biological wastewater treatment, thereby limiting the emergence and propagation of antibiotic resistance in the environment. However, little is known about the specificity of extracellular peptidases derived from wastewater microbial communities, which is a major impediment for the design of sustainable peptide-based antibiotics that can be hydrolyzed by wastewater peptidases. We used a set of natural peptides to explore the specificity of dissolved extracellular wastewater peptidases. We found that enzyme-catalyzed hydrolysis occurred at specific sites and that a subset of these hydrolyses was conserved across enzyme pools derived from three independent wastewater microbial communities. An analysis of the amino-acid residues flanking the hydrolyzed bonds revealed a set of residue motifs that were linked to enzyme-catalyzed hydrolysis and are therefore candidates for incorporation into new and sustainable peptide-based antibiotics.

The Iringa Region is famous among archaeologists for the Acheulean site of Isimila, and among historians as the stronghold where Chief Mkwawa led the Hehe resistance against German colonial forces. However, our research reveals that Iringa has a rich archaeological record that spans the period from the Stone Age into the recent past. This article summarizes the results of 14 years of research by our team, the Iringa Region Archaeological Project (IRAP). Since 2006, IRAP members have recorded 67 sites, and this only scratches the surface of the archaeological potential in the area. These sites, some of which were recorded in conjunction with local participants, have archaeological component characteristic of the Early, Middle, and Later Stone Age, the Iron Age, and the recent past. We consider the archaeological and historical value of Iringa to be high and hope that this work inspires future research, tourism, and conservation efforts in the area., Competing Interests: Conflict of InterestThe authors declare that they have no conflicts of interest., (© The Author(s) 2020.)

Background: Communication between massage therapy patients and their medical providers has not been widely described, especially with respect to health care in the United States., Purpose: To examine which type of medical providers recommend massage therapy (MT), and how often massage therapy patients tell their providers about their treatment., Setting: Independent massage therapy practices in a Practice-based Research Network (PBRN) in Northeast Ohio., Participants: 21 licensed massage therapists (LMT)., Research Design: A cross-sectional descriptive study. For consecutive, nonrepeating visits to their practices, each LMT completed up to 20 cards with information on the patient and visit. Analysis compared visits for patients based on whether they reported telling their health provider about their use of MT or being recommended for massage by a health provider., Results: Among 403 visits to 21 LMTs, 51% of patients had told their primary care clinician about seeing an LMT, and for 23%, a health-care provider had recommended visiting an LMT for that visit. Patients who told their primary care provider that they use massage therapy were more likely to be established patients, or to be seen for chronic pain complaints. Visits recommended by a physician were more likely to be for chronic conditions., Conclusion: Patients who are established in the massage practice and those receiving massage for a specific condition are more likely to tell their primary care provider that they use massage and are also more likely to have been recommended for massage by a health-care provider. This information will help LMTs target and inform patients about the importance of talking with their health-care providers about their use of massage, and provide LMTs with a starting point of which types of health-care providers already recommend massage. This information will further open the dialogue about the integration of massage therapy in conventional health care., Competing Interests: CONFLICT OF INTEREST NOTIFICATION The authors have indicated they have no potential conflicts of interest to disclose.

Introduction  The relationship between inpatient psychiatric experience and subsequent outpatient psychiatric care remains highly understudied. We conducted a voluntary, anonymous, self-report, pilot survey study to explore the impact of current or recent psychiatric hospitalization on patients' ability to trust their outpatient psychiatric providers, particularly with respect to the disclosure of symptoms such as suicidal thoughts. Methods  A survey was conducted in a psychiatry practice-based research network (PBRN) of six outpatient community psychiatry clinic sites within four regional agencies and at an adult inpatient psychiatry unit of a tertiary-care academic hospital in the Cleveland area. We asked patients to record characteristics of their hospitalization, perceived changes in attitudes, and complete a working alliance inventory. Sixty-two surveys were collected. Results  Most respondents had high working alliance scores with their outpatient providers and a low prevalence of coercive experiences during hospitalization. A minority (15%) experienced a reduction in trust with their outpatient provider. Nonetheless, a substantial percentage of respondents expressed a lower likelihood of disclosing various concerning psychiatric symptoms and behaviors to their outpatient provider. Thirty-six percent reported they are less likely to disclose thoughts of harming self. Percentages for subjects reporting a reduced likelihood of disclosing thoughts of harming others, hearing voices, not taking medications as prescribed, and substance use ranged from 21-29%. At the same time, there were also trust-enhancing effects: a substantial number of patients reported an increase in their ability to trust psychiatric providers and an increase in the likelihood of disclosure of psychiatric symptoms. Exploratory analyses revealed significant associations of gender, race, outpatient provider involvement in hospitalization, and involvement of police during admission with trust, disclosure, and working alliance. Conclusion  Even with a high therapeutic alliance and low perceived coercion during inpatient psychiatric hospitalization, the experience can lead to a disruption of trust and transparency with the outpatient psychiatrist in a considerable proportion of patients., Competing Interests: The authors have declared that no competing interests exist.

Triplet-state chromophoric dissolved organic matter ( 3 CDOM*) plays an important role in aquatic photochemistry, yet much remains unknown about the reactivity of these intermediates. To better understand the kinetic behavior and reactivity of 3 CDOM*, we have developed an indirect observation method based on monitoring time-resolved singlet oxygen ( 1 O 2 ) phosphorescence kinetics. The underpinning principle of our approach relies on the fact that O 2 quenches almost all triplets with near diffusion limited rate constants, resulting in the formation of 1 O 2 , which is kinetically linked to the precursors. A kinetic model relating 1 O 2 phosphorescence kinetics to triplet excited states produced from isolated humic substances and in whole natural-water samples (hereafter referred to as 3 CDOM*) was developed and used to determine rate constants governing 3 CDOM* natural lifetimes and quenching by oxygen and 2,4,6-trimethylphenol (TMP), a common triplet probe molecule. 3 CDOM* was found to exhibit smaller O 2 and TMP quenching rate constants, ∼9 × 10 8 and ∼8 × 10 8 M -1 s -1 , respectively, compared with model sensitizers, such as aromatic ketones. Findings from this report shed light on the fundamental photochemical properties of CDOM in organic matter isolates and whole waters and will help refine photochemical models to more accurately predict pollutant fate in the environment.

The antibiotic monensin is fed to dairy cows to increase milk production efficiency. A fraction of this monensin is excreted into the cow manure. Previous studies have found that cow manure containing monensin can negatively impact the performance of anaerobic digesters, especially upon first introduction. Few studies have examined whether the anaerobic digester microbiome can adapt to monensin during the operating time. Here, we conducted a long-term time series study of four lab-scale anaerobic digesters fed with cow manure. We examined changes in both the microbiome composition and function of the anaerobic digesters when subjected to the dairy antibiotic monensin. In our digesters, monensin was not rapidly degraded under anaerobic conditions. The two anaerobic digesters that were subjected to manure from monensin feed-dosed cows exhibited relatively small changes in microbiome composition and function due to relatively low monensin concentrations. At higher concentrations of monensin, which we dosed directly to control manure (from dairy cows without monensin), we observed major changes in the microbiome composition and function of two anaerobic digesters. A rapid introduction of monensin to one of these anaerobic digesters led to the impairment of methane production. Conversely, more gradual additions of the same concentrations of monensin to the other anaerobic digester led to the adaptation of the anaerobic digester microbiomes to the relatively high monensin concentrations. A member of the candidate OP11 ( Microgenomates ) phylum arose in this anaerobic digester and appeared to be redundant with certain Bacteroidetes phylum members, which previously were dominating. IMPORTANCE Monensin is a common antibiotic given to dairy cows in the United States and is partly excreted with dairy manure. An improved understanding of how monensin affects the anaerobic digester microbiome composition and function is important to prevent process failure for farm-based anaerobic digesters. This time series study demonstrates how anaerobic digester microbiomes are inert to low monensin concentrations and can adapt to relatively high monensin concentrations by redundancy in an already existing population. Therefore, our work provides further insight into the importance of microbiome redundancy in maintaining the stability of anaerobic digesters., (Copyright © 2018 Spirito et al.)

Purpose: Clinical and Translational Science Awards (CTSAs) and Practice-based Research Networks (PBRNs) have complementary missions. We replicated a 2008 survey of CTSA-PBRN leaders to understand how organizational relationships have evolved., Methods: We surveyed 60 CTSA community engagement (CE) Directors and 135 PBRN Directors and analyzed data using between and within-group comparisons., Results: Forty-three percent of CTSA CE Directors (26/60) and forty-two percent of PBRN Directors (57/135) responded. Quantitative responses revealed growing alignment between CTSA/PBRN perceptions, with a few areas of discordance. CE Directors noted declining financial support for PBRNs. PBRN Directors identified greater CTSA effectiveness in PBRN engagement, consultation, and collaborative grant submissions. Qualitative data revealed divergent experiences across CTSA/PBRN programs., Conclusions: Relationships between CTSAs and PBRNs are maturing; for some that means strengthening and for others a growing vulnerability. Findings suggest a mutual opportunity for PBRNs and CTSAs around applied research. Studies to characterize exemplar CTSA-PBRN collaborations are needed.

The Mlambalasi rockshelter in the Iringa Region of southern Tanzania has rich artifactual deposits spanning the Later Stone Age (LSA), Iron Age, and historic periods. Middle Stone Age (MSA) artifacts are also present on the slope in front of the rockshelter. Extensive, systematic excavations in 2006 and 2010 by members of the Iringa Region Archaeological Project (IRAP) illustrate a complex picture of repeated occupations and reuse of the rockshelter during an important time in human history. Direct dates on Achatina shell and ostrich eggshell (OES) beads suggest that the earliest occupation levels excavated at Mlambalasi, which are associated with human burials, are terminal Pleistocene in age. This is exceptional given the rarity of archaeological sites, particularly those with human remains and other preserved organic material, from subtropical Africa between 200,000 and 10,000 years before present. This paper reports on the excavations to date and analysis of artifactual finds from the site. The emerging picture is one of varied, ephemeral use over millennia as diverse human groups were repeatedly attracted to this fixed feature on the landscape., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© The Author(s) 2017.)

In this commentary, we propose that practice-based research networks (PBRNs) engage with funders and policymakers by applying the same engagement strategies they have successfully used to build relationships with community stakeholders. A community engagement approach to achieve new funding streams for PBRNs should include a strategy to engage key stakeholders from the communities of funders, thought leaders, and policymakers using collaborative principles and methods. PBRNs that implement this strategy would build a robust network of engaged partners at the community level, across networks, and would reach state and federal policymakers, academic family medicine departments, funding bodies, and national thought leaders in the redesign of health care delivery., Competing Interests: Conflicts of Interest: None declared., (© Copyright 2016 by the American Board of Family Medicine.)

Dissimilatory metal-reducing bacteria are widespread in terrestrial ecosystems, especially in anaerobic soils and sediments. Thermodynamically, dissimilatory metal reduction is more favorable than sulfate reduction and methanogenesis but less favorable than denitrification and aerobic respiration. It is critical to understand the complex relationships, including the absence or presence of terminal electron acceptors, that govern microbial competition and coexistence in anaerobic soils and sediments, because subsurface microbial processes can effect greenhouse gas emissions from soils, possibly resulting in impacts at the global scale. Here, we elucidated the effect of an inexhaustible, ferrous-iron and humic-substance mimicking terminal electron acceptor by deploying potentiostatically poised electrodes in the sediment of a very specific stream riparian zone in Upstate New York state. At two sites within the same stream riparian zone during the course of 6 weeks in the spring of 2013, we measured CH4 and N2/N2O emissions from soil chambers containing either poised or unpoised electrodes, and we harvested biofilms from the electrodes to quantify microbial community dynamics. At the upstream site, which had a lower vegetation cover and highest soil temperatures, the poised electrodes inhibited CH4 emissions by ∼45% (when normalized to remove temporal effects). CH4 emissions were not significantly impacted at the downstream site. N2/N2O emissions were generally low at both sites and were not impacted by poised electrodes. We did not find a direct link between bioelectrochemical treatment and microbial community membership; however, we did find a correspondence between environment/function and microbial community dynamics.

Background: Community engagement and rigorous science are necessary to address health issues. Increasingly, community health organizations are asked to partner in research. To strengthen such community organization-academic partnerships, increase research capacity in community organizations, and facilitate equitable partnered research, the Partners in Education Evaluation and Research (PEER) program was developed. The program implements an 18-month structured research curriculum for one mid-level employee of a health-focused community-based organization with an organizational mentor and a Case Western Reserve University faculty member as partners., Methods: The PEER program was developed and guided by a community-academic advisory committee and was designed to impact the research capacity of organizations through didactic modules and partnered research in the experiential phase. Active participation of community organizations and faculty during all phases of the program provided for bidirectional learning and understanding of the challenges of community-engaged health research. The pilot program evaluation used qualitative and quantitative data collection techniques, including experiences of the participants assessed through surveys, formal group and individual interviews, phone calls, and discussions. Statistical analysis of the change in fellows' pre-test and post-test survey scores were conducted using paired sample t tests. The small sample size is recognized by the authors as a limitation of the evaluation methods and would potentially be resolved by including more cohort data as the program progresses. Qualitative data were reviewed by two program staff using content and narrative analysis to identify themes, describe and assess group phenomena and determine program improvements., Objectives: The objective of PEER is to create equitable partnerships between community organizations and academic partners to further research capacity in said organizations and develop mutually beneficial research partnerships between academia and community organizations., Conclusion: PEER demonstrates a commitment to successfully developing sustainable research capacity growth in community organizations, and improved partnered research with academic institutions.

Here, we studied the microbiome succession and time-scale variability of four mesophilic anaerobic reactors in a co-digestion study with the objective to find links between changing environmental conditions and the microbiome composition. The changing environmental conditions were ensured by gradual increases in loading rates and mixing ratios of three co-substrates with a constant manure-feeding scheme during an operating period longer than 900 days. Each co-substrate (i.e., alkaline hydrolysate, food waste, and glycerol) was co-digested separately. High throughput 16S rRNA gene sequencing was used to examine the microbiome succession. The alkaline hydrolysate reactor microbiome shifted and adapted to high concentrations of free ammonia, total volatile fatty acids, and potassium to maintain its function. The addition of food waste and glycerol as co-substrates also led to microbiome changes, but to a lesser extent, especially in the case of the glycerol reactor microbiome. The divergence of the food waste reactor microbiome was primarily linked to increasing free ammonia levels in the reactor; though, these levels remained below previously reported inhibitory levels for acclimated biomass. The glycerol reactor microbiome succession included an increase in Syntrophomonadaceae family members, which have previously been linked to long-chain fatty acid degradation. The glycerol reactor exhibited rapid failure and limited adaptation at the end of the study., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Metagenomes derived from environmental microbiota encode a vast diversity of protein homologs. How this diversity impacts protein function can be explored through selection assays aimed to optimize function. While artificially generated gene sequence pools are typically used in selection assays, their usage may be limited because of technical or ethical reasons. Here, we investigate an alternative strategy, the use of soil microbial DNA as a starting point. We demonstrate this approach by optimizing the function of a widely occurring soil bacterial enzyme, 1-aminocyclopropane-1-carboxylate (ACC) deaminase. We identified a specific ACC deaminase domain region (ACCD-DR) that, when PCR amplified from the soil, produced a variant pool that we could swap into functional plasmids carrying ACC deaminase-encoding genes. Functional clones of ACC deaminase were selected for in a competition assay based on their capacity to provide nitrogen to Escherichia coli in vitro. The most successful ACCD-DR variants were identified after multiple rounds of selection by sequence analysis. We observed that previously identified essential active-site residues were fixed in the original unselected library and that additional residues went to fixation after selection. We identified a divergent essential residue whose presence hints at the possible use of alternative substrates and a cluster of neutral residues that did not influence ACCD performance. Using an artificial ACCD-DR variant library generated by DNA oligomer synthesis, we validated the same fixation patterns. Our study demonstrates that soil metagenomes are useful starting pools of protein-coding-gene diversity that can be utilized for protein optimization and functional characterization when synthetic libraries are not appropriate., (Copyright © 2016 Jin et al.)

Here's how to use the 5 As, the FRAMES protocol, and 5 other techniques to encourage patients to address issues such as diet, exercise, smoking, and substance use.

Prior investigation of an upflow anaerobic sludge blanket (UASB) reactor treating brewery wastes suggested that direct interspecies electron transfer (DIET) significantly contributed to interspecies electron transfer to methanogens. To investigate DIET in granules further, the electrical conductivity and bacterial community composition of granules in fourteen samples from four different UASB reactors treating brewery wastes were investigated. All of the UASB granules were electrically conductive whereas control granules from ANAMMOX (ANaerobic AMMonium OXidation) reactors and microbial granules from an aerobic bioreactor designed for phosphate removal were not. There was a moderate correlation (r=0.67) between the abundance of Geobacter species in the UASB granules and granule conductivity, suggesting that Geobacter contributed to granule conductivity. These results, coupled with previous studies, which have demonstrated that Geobacter species can donate electrons to methanogens that are typically predominant in anaerobic digesters, suggest that DIET may be a widespread phenomenon in UASB reactors treating brewery wastes., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Purpose: To define the concept of "health care insecurity,” validate a new self-report measure, and examine the impact of beginning care at a free clinic on uninsured patients' health care insecurity., Methods: Consecutive new patients presenting at a free clinic completed 15 items assessing domains of health care insecurity (HCI) at their first visit and again four to eight weeks later. Psychometrics and change of the HCI measure were examined., Results: The HCI measure was found to have high internal consistency (α=0.94). Evidence of concurrent validity was indicated by negative correlation with VR-12 health-related quality of life physical and mental health components and positive correlation with the Perceived Stress Scale. Predictive validity was shown among the 83% of participants completing follow-up: HCI decreased after beginning care at a free clinic (p<.001)., Conclusion: Reliably assessing patient experience of health care insecurity is feasible and has potential to inform efforts to improve quality and access to care among underserved populations.

There is often a rich but untold history of events that occur and relationships that form before a practice-based research network (PBRN) is launched. This is particularly the case in PBRNs that are community based and comprise partnerships outside of the health care system. In this article we summarize an organizational "prenatal history" before the birth of a PBRN devoted to people with developmental disabilities. Using a case study approach, this article describes the historic events that preceded and fostered the evolution of this PBRN and contrasts how the processes leading to the creation of this multistakeholder, community-based PBRN differ from those of typical academic/clinical practice PBRNs. We propose potential advantages and complexities inherent to this newest iteration of PBRNs., (© Copyright 2014 by the American Board of Family Medicine.)

Practice-based research networks (PBRNs) have developed a grounded approach to conducting practice-relevant and translational research in community practice settings. Seismic shifts in the health care landscape are shaping PBRNs that work across organizational and institutional margins to address complex problems. Praxis-based research networks combine PBRN knowledge generation with multistakeholder learning, experimentation, and application of practical knowledge. The catalytic processes in praxis-based research networks are cycles of action and reflection based on experience, observation, conceptualization, and experimentation by network members and partners. To facilitate co-learning and solution-building, these networks have a flexible architecture that allows pragmatic inclusion of stakeholders based on the demands of the problem and the needs of the network. Praxis-based research networks represent an evolving trend that combines the core values of PBRNs with new opportunities for relevance, rigor, and broad participation., (© Copyright 2014 by the American Board of Family Medicine.)

This study found that there is alignment between a patient's reason for a visit and the physician's main concern 69% of the time. Less than fully aligned priorities were associated with insurance status and the number of problems addressed.

Background and Objectives: Strengthening the contribution of reflective practice and new knowledge generation to the learning relationships forged during graduate and undergraduate medical training offers a possibility to create a climate more conducive to the recruitment and retention of family physicians. The Culture of Inquiry (CI) fellowship, an immersive, experientially based training program, combines didactic instruction, workshops, and mentoring to develop the capacity of family medicine's teachers to imagine, implement, and disseminate clinically relevant research and stimulate collaborations with those whom they train. This article outlines the CI fellowship program, summarizes its outcomes, and offers insights about programmatic features contributing to its success., Methods: The Department of Family Medicine and Community Health at Case Western Reserve University selected CI fellows from interested local family physicians who train residents and medical students. Over 10 months, with 10% effort expected from fellows, the CI fellowship exposed each fellow to the entire research process and provided technical and logistical support for the design and completion of two research projects. Quantitative and qualitative program evaluation were used to assess outcomes., Results: Scholarly productivity of fellows exceeded expectations. Collaborations with students and residents produced a ripple effect that amplified the fellowship's impact by strengthening those relationships crucial to the creation of a culture of inquiry among family medicine's teachers, learners, and practitioners., Conclusions: The CI fellowship represents a highly replicable program to connect committed and interested clinicians to research mentors with the goal of increasing scholarship and creating a growing culture of inquiry in family medicine.

Anaerobic digesters rely on the diversity and distribution of parallel metabolic pathways mediated by complex syntrophic microbial communities to maintain robust and optimal performance. Using mesophilic swine waste digesters, we experimented with increased ammonia loading to induce a shift from aceticlastic methanogenesis to an alternative acetate-consuming pathway of syntrophic acetate oxidation. In comparison with control digesters, we observed shifts in bacterial 16S rRNA gene content and in functional gene repertoires over the course of the digesters' 3-year operating period. During the first year, under identical startup conditions, all bioreactors mirrored each other closely in terms of bacterial phylotype content, phylogenetic structure, and evenness. When we perturbed the digesters by increasing the ammonia concentration or temperature, the distribution of bacterial phylotypes became more uneven, followed by a return to more even communities once syntrophic acetate oxidation had allowed the experimental bioreactors to regain stable operation. The emergence of syntrophic acetate oxidation coincided with a partial shift from aceticlastic to hydrogenotrophic methanogens. Our 16S rRNA gene analysis also revealed that acetate-fed enrichment experiments resulted in communities that did not represent the bioreactor community. Analysis of shotgun sequencing of community DNA suggests that syntrophic acetate oxidation was carried out by a heterogeneous community rather than by a specific keystone population with representatives of enriched cultures with this metabolic capacity.

The respiratory tract of cystic fibrosis (CF) patients harbor persistent microbial communities (CF airway microbiome) with Pseudomonas aeruginosa emerging as a dominant pathogen. Within a polymicrobial infection, interactions between co-habitant microbes can be important for pathogenesis, but even when considered, these interactions are not well understood. Here, we show with in vitro experiments that, compared with glucose, common fermentation products from co-habitant bacteria significantly increase virulence factor production, antimicrobial activity and biofilm formation of P. aeruginosa. The maximum stimulating effect was produced with the fermentation product 2,3-butanediol, which is a substrate for P. aeruginosa, resulting in a metabolic relationship between fermenters and this pathogen. The global transcription regulator LasI LasR, which controls quorum sensing, was upregulated threefold with 2,3-butanediol, resulting in higher phenazine and exotoxin concentrations and improved biofilm formation. This indicates that the success of P. aeruginosa in CF airway microbiomes could be governed by the location within the food web with fermenting bacteria. Our findings suggest that interbacterial metabolite transfer in polymicrobial infections stimulates virulence of P. aeruginosa and could have a considerable impact on disease progression.

The goal of this study was to obtain causative information about beta-diversity (differentiation between microbiomes) by comparing sequencing information between studies rather than just knowledge about alpha-diversity (microbiome richness). Here, published sequencing data were merged representing 78 anaerobic digester samples originating from 28 different studies for an overall comparison of beta-diversity (measured using unweighted UniFrac). It was found that digester microbiomes based on bacterial sequences clustered by substrate type, independent of the study of origin, and that this clustering could be attributed to distinct bacterial lineages., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

High productivity and specificity in anaerobic digesters arise because complex microbiomes organize into a metabolic cascade to maximize energy recovery and to utilize the advantage that the gaseous end product methane freely bubbles out of the system. These lessons were applied to ascertain whether a reactor microbiome could be shaped to produce a different end product. The liquid product n-caproic acid was chosen, which is a 6-carbon-chain carboxylic acid that is valuable and that has a relatively low maximum solubility concentration for product recovery. Acetoclastic methanogenesis was inhibited by pH control and a route was provided for n-caproic acid extraction by implementing selective, in-line recovery. Next, ethanol was supplemented to promote chain elongation, which is a pathway in which short-chain carboxylic acids are elongated sequentially into medium-chain carboxylic acids with two-carbon units derived from ethanol. The reactor microbiome developed accordingly with the terminal process catalyzed by chain-elongating bacteria. As a result, n-caproic acid production rates increased to levels comparable to anaerobic digestion systems for solid waste treatment.

Gut mucosal barrier breakdown and inflammation have been associated with high levels of flagellin, the principal bacterial flagellar protein. Although several gut commensals can produce flagella, flagellin levels are low in the healthy gut, suggesting the existence of control mechanisms. We find that mice lacking the flagellin receptor Toll-like receptor 5 (TLR5) exhibit a profound loss of flagellin-specific immunoglobulins (Igs) despite higher total Ig levels in the gut. Ribotyping of IgA-coated cecal microbiota showed Proteobacteria evading antibody coating in the TLR5(-/-) gut. A diversity of microbiome members overexpressed flagellar genes in the TLR5(-/-) host. Proteobacteria and Firmicutes penetrated small intestinal villi, and flagellated bacteria breached the colonic mucosal barrier. In vitro, flagellin-specific Ig inhibited bacterial motility and downregulated flagellar gene expression. Thus, innate-immunity-directed development of flagellin-specific adaptive immune responses can modulate the microbiome's production of flagella in a three-way interaction that helps to maintain mucosal barrier integrity and homeostasis., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objectives: This study examined the degree of similarity between motivational interviewing (MI) methods and smoking cessation techniques that are routinely used by primary care physicians. Its purpose was to inform the development of more effective MI-based health behavior change training programs for primary care physicians., Methods: Visits to primary care physicians were audio-recorded in northeast Ohio from 2005 to 2008. Doctor-patient talk about smoking cessation (n = 73) was analyzed for adherence to MI using the Motivational Interviewing Skills Code (MISC) version 2.1 behavioral coding system. Participating physicians were not provided with MI training as part of the study and were blinded as to the study's purpose., Results: Physicians displayed MI adherent behaviors in 56% of discussions and MI nonadherent behaviors in 57%. The most common MI adherent statements involved affirming the patient; least common were requests for the patient's permission before raising concerns. The most frequent MI nonadherent behaviors were directing, confronting, and warning the patient. Physicians made simple reflections and complex reflections in 36% and 25% of visits, respectively., Conclusions: Physicians used both MI adherent and MI nonadherent behaviors in approximately equal proportions, suggesting a base of MI adherent smoking cessation counseling skills upon which additional MI skills can be built. Efforts to improve smoking-cessation effectiveness may involve providing training in brief MI models and additional MI skills, while reinforcing physicians' current use of MI adherent methods.

Research has illuminated the problem of untreated mental illness among young adults, including evidence that young people who exit public care systems often discontinue mental health services in adulthood. The present study explored mental health service use experiences during the transition to adulthood among sixty young adults, ages 18-25, from a Midwestern U.S. state. In-depth semi-structured interviews were conducted. All participants had mood difficulties, and shared three childhood experiences: (a) mood disorder diagnosis; (b) use of public mental health services; and (c) experience with social service systems. Immersion and grounded theory coding techniques were applied to the interview data. Two major themes about mental health service use emerged from the findings, namely the changing nature of service use over time and characterizations of experiences associated with service use at a given point in time. Categories of explanatory constructs that emerged in the latter theme included perceived need, emotions, perceived efficacy of services, and social considerations, among others. Findings suggested a four-facet mid-level theory of service utilization, highlighting both the cross-sectional and time-variant character of service use and decision-making within context. Links between broader theoretical frameworks of service utilization and social psychological models of decision making were noted, and guidelines were presented for ten classes of variables that researchers interested in understanding service use by young adults should consider., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

To maximize the production of carboxylic acids with open cultures of microbial consortia (reactor microbiomes), we performed experiments to understand which factors affect the community dynamics and performance parameters. We operated six thermophilic (55 °C) bioreactors to test how the factors: (i) biomass pretreatment; (ii) bioreactor operating conditions; and (iii) bioreactor history (after perturbations during the operating period) affected total fermentation product and n-butyrate performance parameters with corn fiber as the cellulosic biomass waste. We observed a maximum total fermentation product yield of 39%, a n-butyrate yield of 23% (both on a COD basis), a maximum total fermentation production rate of 0.74 g COD l(-1) d(-1) and n-butyrate production rate of 0.47 g COD l(-1) d(-1) in bioreactors that were fed with dilute-acid pretreated corn fiber at a pH of 5.5. Pyrosequencing of 16S rRNA genes with constrained ordination and other statistical methods showed that changes in operating conditions to enable dilution of toxic carboxylic acid products, which lead to these maximum performance parameters, also altered the composition of the microbiome, and that the microbiome, in turn, affected the performance. Operating conditions are an important factor (tool for operators) to shape reactor microbiomes, but other factors, such as substrate composition after biomass pretreatment and bioreactor history are also important. Further optimization of operating conditions must relieve the toxicity of carboxylic acids at acidic bioreactor pH levels even more, and this can, for example, be accomplished by extracting the product from the bioreactor solutions.

Molecular biomarkers could provide critical insight into myriad in situ microbial activities. In this study we explore correlations of both mRNA and protein biomarkers with chloroethene respiration rate in Dehalococcoides. In a series of continuously fed dechlorinating mixed-culture microcosm experiments (n = 26), we varied respiratory substrates, substrate ratios and feeding rates. Transcript levels for most biomarkers were responsive down to 0.01× the culture's maximum respiration rate. The dehalogenase TceA and the Ni-Fe hydrogenase HupL transcripts were positively correlated (Pearson's r of 0.89 and 0.88, respectively) with respiration rates on log-log plots between 1.5 and 280 μeeq/L-hr for mRNA abundances of 10(7) to 10(10) transcripts/mL (0.07-230 transcripts/genome). These trends were independent of the types of chloroethene or electron donors fed. Other mRNA target levels plateaued or declined at respiration rates above 5 μeeq/L-hr. Using both relative and absolute protein quantification methods, we found that per-genome protein abundances of most targeted biomarkers did not statistically change over the experimental time frames. However, quantified enzyme levels allowed us to calculate in vivo enzyme-specific rate constants (k(cat)) for the dehalogenases PceA and TceA: 400 and 22 substrate molecules/enzyme-sec, respectively. Overall, these data support the promise of both mRNA and protein biomarkers for estimating process rates through either empirical (mRNA-based) or kinetic (protein-based) models, but they require follow-up studies in other cultures and at active remediation sites.

Many of the immune and metabolic changes occurring during normal pregnancy also describe metabolic syndrome. Gut microbiota can cause symptoms of metabolic syndrome in nonpregnant hosts. Here, to explore their role in pregnancy, we characterized fecal bacteria of 91 pregnant women of varying prepregnancy BMIs and gestational diabetes status and their infants. Similarities between infant-mother microbiotas increased with children's age, and the infant microbiota was unaffected by mother's health status. Gut microbiota changed dramatically from first (T1) to third (T3) trimesters, with vast expansion of diversity between mothers, an overall increase in Proteobacteria and Actinobacteria, and reduced richness. T3 stool showed strongest signs of inflammation and energy loss; however, microbiome gene repertoires were constant between trimesters. When transferred to germ-free mice, T3 microbiota induced greater adiposity and insulin insensitivity compared to T1. Our findings indicate that host-microbial interactions that impact host metabolism can occur and may be beneficial in pregnancy., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background and Objectives: Doctoral trained faculty educators increase faculty physicians' skills and capacities by implementing training and mentoring programs in academic primary care departments. The purpose of this study was to describe the characteristics, roles, challenges, and satisfaction of faculty educators working in departments of family medicine and to report perceptions of their work environment., Methods: The data for this study derive from a 2009 national survey of all full-time doctoral-level faculty members, including educators, working in US academic departments of family medicine. Items included demographics, roles, research output, financial support, and perceptions of the work environment. Descriptive statistics including means and percentages were used to compare public and private institutions., Results: Twenty-five full-time faculty educators responded to the survey. Median age was 57 years; median years worked was 17, with 52% holding the rank of associate or full professor. Differences were observed between public and private institutions in terms of how time is spent, sources of funding, rates of tenure, and number of grants and publications. Job-related perceptions were mostly positive, indicating a good fit of training and job responsibilities. Areas of dissatisfaction included feelings of being over committed and increased job stress., Conclusions: As senior faculty educators retire, it is important to assure that the torch is passed to new faculty educators who can meet the professional development needs of future generations of family physicians.

Taxonomic classification of the thousands-millions of 16S rRNA gene sequences generated in microbiome studies is often achieved using a naïve Bayesian classifier (for example, the Ribosomal Database Project II (RDP) classifier), due to favorable trade-offs among automation, speed and accuracy. The resulting classification depends on the reference sequences and taxonomic hierarchy used to train the model; although the influence of primer sets and classification algorithms have been explored in detail, the influence of training set has not been characterized. We compared classification results obtained using three different publicly available databases as training sets, applied to five different bacterial 16S rRNA gene pyrosequencing data sets generated (from human body, mouse gut, python gut, soil and anaerobic digester samples). We observed numerous advantages to using the largest, most diverse training set available, that we constructed from the Greengenes (GG) bacterial/archaeal 16S rRNA gene sequence database and the latest GG taxonomy. Phylogenetic clusters of previously unclassified experimental sequences were identified with notable improvements (for example, 50% reduction in reads unclassified at the phylum level in mouse gut, soil and anaerobic digester samples), especially for phylotypes belonging to specific phyla (Tenericutes, Chloroflexi, Synergistetes and Candidate phyla TM6, TM7). Trimming the reference sequences to the primer region resulted in systematic improvements in classification depth, and greatest gains at higher confidence thresholds. Phylotypes unclassified at the genus level represented a greater proportion of the total community variation than classified operational taxonomic units in mouse gut and anaerobic digester samples, underscoring the need for greater diversity in existing reference databases.

Purpose: The "card study," in which clinicians record brief information about patient visits during usual clinical care, has long been a rapid method for conducting descriptive studies in practice-based research networks. Because an increasingly stringent regulatory environment has made conducting card studies difficult, we developed a streamlined method for obtaining card study institutional review board (IRB) approval., Methods: We developed a protocol for a study of the card study method, allowing new card study proposals of specific research questions to be submitted as addenda to the approved Card Study Protocol., Results: Seven card studies were proposed and approved under the Card Study Protocol during the first year after implementation, contrasted with one-card study proposed in the previous year. New card study ideas submitted as addenda to an approved protocol appeared to increase IRB comfort with the card study as a minimal risk method while reducing the hurdles to developing new study ideas., Conclusions: A Card Study Protocol allowing new study questions to be submitted as addenda decreases time between idea generation and IRB approval. Shortened turn-around times may be useful for translating ideas into action while reducing regulatory burden.

Anaerobic digestion is the most successful bioenergy technology worldwide with, at its core, undefined microbial communities that have poorly understood dynamics. Here, we investigated the relationships of bacterial community structure (>400,000 16S rRNA gene sequences for 112 samples) with function (i.e., bioreactor performance) and environment (i.e., operating conditions) in a yearlong monthly time series of nine full-scale bioreactor facilities treating brewery wastewater (>20,000 measurements). Each of the nine facilities had a unique community structure with an unprecedented level of stability. Using machine learning, we identified a small subset of operational taxonomic units (OTUs; 145 out of 4,962), which predicted the location of the facility of origin for almost every sample (96.4% accuracy). Of these 145 OTUs, syntrophic bacteria were systematically overrepresented, demonstrating that syntrophs rebounded following disturbances. This indicates that resilience, rather than dynamic competition, played an important role in maintaining the necessary syntrophic populations. In addition, we explained the observed phylogenetic differences between all samples on the basis of a subset of environmental gradients (using constrained ordination) and found stronger relationships between community structure and its function rather than its environment. These relationships were strongest for two performance variables--methanogenic activity and substrate removal efficiency--both of which were also affected by microbial ecology because these variables were correlated with community evenness (at any given time) and variability in phylogenetic structure (over time), respectively. Thus, we quantified relationships between community structure and function, which opens the door to engineer communities with superior functions.

Objective: To examine how medically uninsured patients who receive health care at federally qualified health centers and free clinics are able to successfully self-manage diabetes compared to patients who are less successful., Methods: Two distinct groups of patients with diabetes for 6 months or longer were enrolled: (1) successful, defined as those with glycated hemoglobin (HbA1c) of 7% or less or a recent improvement of at least 2% (n=17); and (2) unsuccessful, defined as patients with HbAlc of at least 9% (n=9) and without recent improvement. Patients were interviewed about enabling factors, motivators, resources, and barriers to diabetes self-management. Data from interviews, chart reviews, and clinician surveys were analyzed using qualitative methods and statistical techniques., Results: African Americans comprised 57.7% of the sample and whites 38.5% (N=26). No significant differences were detected between successful and unsuccessful groups in age, race, education, or employment status. Clinicians rated unsuccessful patients as having more severe diabetes and significantly lower levels of control than successful patients. Compared to unsuccessful patients, successful patients more often reported having friends or family with diabetes, more frequently sought information about the disease, used evidence-based self-management strategies, held more accurate perceptions of their own diabetes control, and experienced "turning point" events that motivated increased efforts in disease management., Conclusions: Patients who successfully managed diabetes learned from diabetic family members and interpreted disease-related events as motivational turning points. It may be beneficial to incorporate social learning and motivational enhancement into diabetes interventions to increase patients' motivation for improved levels of self-management.

Purpose: To test the effect of an Appreciative Inquiry (AI) quality improvement strategy on clinical quality management and practice development outcomes. Appreciative inquiry enables the discovery of shared motivations, envisioning a transformed future, and learning around the implementation of a change process., Methods: Thirty diverse primary care practices were randomly assigned to receive an AI-based intervention focused on a practice-chosen topic and on improving preventive service delivery (PSD) rates. Medical-record review assessed change in PSD rates. Ethnographic field notes and observational checklist analysis used editing and immersion/crystallization methods to identify factors affecting intervention implementation and practice development outcomes., Results: The PSD rates did not change. Field note analysis suggested that the intervention elicited core motivations, facilitated development of a shared vision, defined change objectives, and fostered respectful interactions. Practices most likely to implement the intervention or develop new practice capacities exhibited 1 or more of the following: support from key leader(s), a sense of urgency for change, a mission focused on serving patients, health care system and practice flexibility, and a history of constructive practice change., Conclusions: An AI approach and enabling practice conditions can lead to intervention implementation and practice development by connecting individual and practice strengths and motivations to the change objective.

Purpose: Practice-based research networks (PBRNs) are a part of many National Institutes of Health (NIH)-funded Clinical and Translational Science Award (CTSA) sites. PBRNs, groups of primary care practices committed to collaborating on practice-relevant research, are unfamiliar to many CTSA leaders. Conversely, the CTSAs, as new research structures designed to transform clinical research, are unfamiliar to many PBRN directors. This study examined the extent to which these programs have congruent goals and expectations, and whether their engagement is likely to be mutually beneficial., Method: The authors sent a Web-based survey to 38 CTSA community engagement directors and a similar survey to 114 PBRN directors during the fall of 2008., Results: A total of 66% (25/38) CTSA community engagement directors and 61% (69/114) PBRN directors responded. Two thirds of responding CTSAs reported working with PBRNs, and over half of responding PBRNs reported a CTSA affiliation. Both groups indicated this relationship was important. CTSAs looked to PBRNs for access to patients and expertise in engaging communities and clinical practices. PBRNs reported seeking stable infrastructure support and greater collaboration and visibility in the academic research community. PBRN infrastructure support from CTSAs was highly variable. Both groups perceived considerable promise for building sustainable relationships and a bidirectional flow of information and research opportunities., Conclusions: With fewer than three years of experience, the PBRN/CTSA relationship remains in the discovery phase; the participants are still negotiating expectations. If these collaborations prove mutually beneficial, they may advance the community engagement goals of many academic health centers.

The quantification of trace proteins in complex environmental samples and mixed microbial communities would be a valuable monitoring tool in countless applications, including the bioremediation of groundwater contaminated with chlorinated solvents. Measuring the concentrations of specific proteins provides unique information about the activity and physiological state of organisms in a sample. We developed sensitive (< 5 fmol), selective bioindicator assays for the absolute quantification of select proteins used by Dehalococcoides spp. when reducing carbon atoms in the common pollutants trichloroethene (TCE) and tetrachloroethene (PCE). From complex whole-sample digests of two different dechlorinating mixed communities, we monitored the chromatographic peaks of selected tryptic peptides chosen to represent 19 specific Dehalococcoides proteins. This was accomplished using multiple-reaction monitoring (MRM) assays using nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS), which provided the selectivity, sensitivity and reproducibility required to quantify Dehalococcoides proteins in complex samples. We observed reproducible peak areas (average CV = 0.14 over 4 days, n = 3) and linear responses in standard curves (n = 5, R(2) > 0.98) using synthetic peptide standards spiked into a background matrix of sediment peptides. We detected and quantified TCE reductive dehalogenase (TceA) at 7.6 +/- 1.7 x 10(3) proteins cell(-1) in the KB1 bioaugmentation culture, previously thought to be lacking TceA. Fragmentation data from MS/MS shotgun proteomics experiments were helpful in developing the MRM targets. Similar shotgun proteomics data are emerging in labs around the world for many environmentally relevant microbial proteins, and these data are a valuable resource for the future development of MRM assays. We expect targeted peptide quantification in environmental samples to be a useful tool in environmental monitoring.

Chlortetracycline, an antibiotic commonly used as a growth promoter in livestock, enters the environment primarily through application of animal waste to open fields. The photochemical loss of chlortetracycline in sunlight-exposed soils is a potentially important process in its environmental fate, especially because it is photochemically labile and sorbs strongly to mineral surfaces. In this study, photolysis on kaolinite clay under simulated sunlight was used as a model system to elucidate the mechanistic kinetics of chlortetracycline photolysis on soil surfaces. The results suggest that photolysis may be an important loss process for chlortetracycline sorbed to sunlight-exposed soils, as well as to suspended clays in surface waters. Under direct irradiation equivalent to noon-time, summer sunlight in the midwestern United States, chlortetracycline at the outer clay surface (before light attenuation) degraded with a rate constant of k(0)(p) = 0.65 +/- 0.30 h(-1). The depth at which photochemical action was reduced by 50% (z(0.5)), one of the parameters of the mechanistic model, was found to be 0.014 +/- 0.004 mm. The quantum yield on the clay surface was estimated to be (1.3 +/- 0.7) x 10(-4), an order of magnitude lower than the quantum yield of the aqueous chlortetracycline zwitterion [(1.3 +/- 0.3) x 10(-3); pH 5], although still significant.

Background: The majority of adult women in the United States fail to meet daily calcium intake recommendations. This study was undertaken to (1) identify predictors of calcium supplement use versus non-use, (2) understand barriers to calcium supplementation, and (3) determine the potential impact of physician recommendation on calcium supplement use., Methods: Surveys were self-administered by 185 women, ages 20 to 64, presenting consecutively for care at 6 suburban community-based family medicine practices within the Cleveland Clinic Ambulatory Research Network (CleAR-eN). We compared demographic characteristics, health beliefs, and health behaviors of those women who reported never using calcium supplements with those who presently took calcium supplements. Women who never took calcium were also queried about reasons for non-use and whether physician recommendation would influence their adoption of calcium supplementation., Results: Multivitamin use, self-perceived risk of osteoporosis, and age were independent predictors of calcium supplement use. Leading barriers for never-users were lack of knowledge about the need/importance of increasing calcium intake, lack of motivation to start supplements, and the belief that their dietary calcium intake alone was sufficient. Ninety-six percent of never-users reported that they would consider taking a calcium supplement if recommended by their physician., Conclusions: Many patient-identified barriers to calcium supplementation seem amenable to focused and brief office-based interventions that could increase the number of women meeting calcium intake guidelines.

Purpose: We compared the completeness of data collection using paper forms and using electronic forms loaded on handheld computers in an office-based patient interview survey conducted within the American Academy of Family Physicians National Research Network., Methods: We asked 19 medical assistants and nurses in family practices to administer a survey about pneumococcal immunizations to 60 older adults each, 30 using paper forms and 30 using electronic forms on handheld computers. By random assignment, the interviewers used either the paper or electronic form first. Using multilevel analyses adjusted for patient characteristics and clustering of forms by practice, we analyzed the completeness of the data., Results: A total of 1,003 of the expected 1,140 forms were returned to the data center. The overall return rate was better for paper forms (537 of 570, 94%) than for electronic forms (466 of 570, 82%) because of technical difficulties experienced with electronic data collection and stolen or lost handheld computers. Errors of omission on the returned forms, however, were more common using paper forms. Of the returned forms, only 3% of those gathered electronically had errors of omission, compared with 35% of those gathered on paper. Similarly, only 0.04% of total survey items were missing on the electronic forms, compared with 3.5% of the survey items using paper forms., Conclusions: Although handheld computers produced more complete data than the paper method for the returned forms, they were not superior because of the large amount of missing data due to technical difficulties with the hand-held computers or loss or theft. Other hardware solutions, such as tablet computers or cell phones linked via a wireless network directly to a Web site, may be better electronic solutions for the future.

The environmental photochemical kinetics of tylosin, a common veterinary macrolide antibiotic and growth promoter, were investigated under simulated sunlight. An efficient, reversible photoisomerization was characterized using kinetic, mass spectrometry, and proton nuclear magnetic resonance data. The photoisomerization was confirmed to occur by a rotation about the distal alkene of the ketodiene functionality. Concurrent forward (quantum yield = 0.39 +/- 0.09) and back (quantum yield = 0.32 +/- 0.08) reactions lead to a photochemical equilibrium near a tylosin/photoisomer ratio of 50:50, completed in less than 2 min under a spectrum equivalent to noontime, summer sunlight. The activity of the isomer for the inhibition of Escherichia coli DH5alpha growth was observed to be less than that of tylosin. On a longer time scale than that of isomerization, the isomer mixture undergoes photolysis with a quantum yield of (1.4 +/- 0.3) x 10(-3). The observed quantum yields and UV-vis absorbance data allow for the prediction of the photochemical behavior of tylosin in most environmental systems. Indirect photosensitization was not a significant loss process in solutions of Suwannee River fulvic acid with concentrations from 1 to 20 mg L(-1).

The environmental photochemical kinetics of the antibiotic compound tetracycline were investigated. The aqueous speciation of tetracycline over a range of natural pH and water hardness values is dominated by association with Ca2+ and Mg2+ ions. The association constants necessary to calculate tetracycline aqueous speciation given knowledge of pH, [Ca2+], and [Mg2+] were measured by spectrophotometric titrations and matrix deconvolution of a series of UV-vis absorption spectra into individual component species. A series of photolysis experiments was performed under simulated sunlight, and quantum yields for the solar photolysis of each environmentally relevant species were calculated. The results indicate that the pseudo-first-order rate constant for tetracycline photolysis at varied Mg2+ and Ca2+ concentrations relevant to natural conditions can vary by up to an order of magnitude. A self-sensitization effect was observed and was accounted for by varying the initial tetracycline concentration under each set of photolysis conditions.

Pharmaceuticals and personal care products are an emerging class of environmental pollutants. Photolysis is expected to be a major loss process for many of these compounds in surface waters, including the common non-steroidal anti-inflammatory drug mefenamic acid. The direct photolysis solar quantum yield of mefenamic acid was observed to be 1.5+/-0.3x10(-4). Significant photosensitization was observed in solutions of Suwanee River fulvic acid and Mississippi River water, as well as for the model photosensitization compounds 3'-methoxyacetophenone, 2-acetonaphthone and perinaphthenone. Quenching, sparging and light-filtering experiments suggested a direct reaction of mefenamic acid with excited triplet-state dissolved organic matter as the major photosensitization process. The persistence of the model photosensitizer suggests that the photosensitization by perinaphthenone occurs either by triplet-energy transfer or an electron transfer followed by rapid regeneration of the sensitizer. Due to its low quantum yield, the loss of mefenamic acid in sunlit natural waters is expected to depend on both direct and indirect photodegradation processes.

Objectives: The specialty referral process is one of the chief targets of managed care constraints on ambulatory medical decision-making. This study examines the influence of gatekeeping arrangements and capitated primary care physician (PCP) payment on the specialty referral process in primary care settings., Research Design: Primary care practice-based study of referred and nonreferred office visits., Subjects: The study comprised 14,709 visits made by privately insured, nonelderly patients who were seen by 139 primary care physicians in 80 practices located in 31 states., Measures: Visits were grouped by health plan type: gatekeeping with capitated PCP payment; gatekeeping with fee-for-service PCP payment; no gatekeeping. Dependent measures included the proportion of visits referred, characteristics of referrals, and physician coordination activities., Results: The percentages of office visits resulting in a referral were similar between the two gatekeeping groups and higher than the no gatekeeping group. Patients in plans with capitated PCP payment were more likely to be referred for discretionary indications than those in nongatekeeping plans (15.5% v 9.9%, P < 0.05). The frequency of referring physician coordination activities did not vary by health plan type. The proportion of patients in gatekeeping health plans within a practice was directly related to employing staff as referral coordinators, allowing nurses to refer without physician consultation, and permitting patients to request referrals by leaving recorded telephone messages., Conclusion: The specialty referral process for privately insured nonelderly patients enrolled in managed health plans is generally similar, regardless of the presence of gatekeeping arrangements and capitated PCP payment. An increase in the number of discretionary referrals among patients in plans with capitated PCP payment provides support for exploring strategies that encourage PCPs to manage in their entirety conditions that straddle the boundaries between primary and specialty care. In response to increasing numbers of patients enrolled in managed health plans with gatekeeping arrangements, physicians appear to modify the structure of their practices to facilitate access to and coordination of referrals.