Precision Education: The Future of Lifelong Learning in Medicine.

ABSTRACT: The goal of medical education is to produce a physician workforce capable of delivering high-quality equitable care to diverse patient populations and communities. To achieve this aim amidst explosive growth in medical knowledge and increasingly complex medical care, a system of personalized and continuous learning, assessment, and feedback for trainees and practicing physicians is urgently needed. In this perspective, the authors build on prior work to advance a conceptual framework for such a system: precision education (PE).PE is a system that uses data and technology to transform lifelong learning by improving personalization, efficiency, and agency at the individual, program, and organization levels. PE "cycles" start with data inputs proactively gathered from new and existing sources, including assessments, educational activities, electronic medical records, patient care outcomes, and clinical practice patterns. Through technology-enabled analytics , insights are generated to drive precision interventions . At the individual level, such interventions include personalized just-in-time educational programming. Coaching is essential to provide feedback and increase learner participation and personalization. Outcomes are measured using assessment and evaluation of interventions at the individual, program, and organizational levels, with ongoing adjustment for repeated cycles of improvement. PE is rooted in patient, health system, and population data; promotes value-based care and health equity; and generates an adaptive learning culture.The authors suggest fundamental principles for PE, including promoting equity in structures and processes, learner agency, and integration with workflow (harmonization). Finally, the authors explore the immediate need to develop consensus-driven standards: rules of engagement between people, products, and entities that interact in these systems to ensure interoperability, data sharing, replicability, and scale of PE innovations.

A Theoretical Foundation to Inform the Implementation of Precision Education and Assessment.

ABSTRACT: Precision education (PE) uses personalized educational interventions to empower trainees and improve learning outcomes. While PE has the potential to represent a paradigm shift in medical education, a theoretical foundation to guide the effective implementation of PE strategies has not yet been described. Here, the authors introduce a theoretical foundation for the implementation of PE, integrating key learning theories with the digital tools that allow them to be operationalized. Specifically, the authors describe how the master adaptive learner (MAL) model, transformative learning theory, and self-determination theory can be harnessed in conjunction with nudge strategies and audit and feedback dashboards to drive learning and meaningful behavior change. The authors also provide practical examples of these theories and tools in action by describing precision interventions already in use at one academic medical center, concretizing PE's potential in the current clinical environment. These examples illustrate how a firm theoretical grounding allows educators to most effectively tailor PE interventions to fit individual learners' needs and goals, facilitating efficient learning and ultimately improving patient and health system outcomes.

"What matters to you?": The relevance of patient priorities in dialysis care for assessment and clinical practice.

BACKGROUND: Dialysis patients are confronted with numerous, complex problems, which make it difficult to identify individual patient's most prominent problems. The objectives of this study were to (1) identify dialysis patients' most prominent problems from a patient perspective and (2) to calculate disease-specific norms for questionnaires measuring these problems. METHODS: One hundred seventy-five patients treated with hemodialysis or peritoneal dialysis completed a priority list on several domains of functioning (e.g., physical health, mental health, social functioning, and daily activities) and a set of matching questionnaires assessing patient functioning on these domains. Patient priorities were assessed by calculating the importance ranking of each domain on the priority list. Subsequently, disease-specific norm scores were calculated for all questionnaires, both for the overall sample and stratified by patient characteristics. RESULTS: Fatigue was listed as patients' most prominent problem. Priorities differed between male and female patients, younger and older patients, and home and center dialysis patients, which was also reflected in their scores on the corresponding domains of functioning. Therefore, next to general norm scores, we calculated corrections to the general norms to take account of patient characteristics (i.e., sex, age, and dialysis type). CONCLUSIONS: Results highlight the importance of having attention for the specific priorities and needs of each individual patient. Adequate disease-specific, norm-based assessment is not only necessary for diagnostic procedures but is an essential element of patient-centered care: It will help to better understand and respect individual patient needs and tailor treatment accordingly.

Validation of the Withdrawal Assessment Tool-1 in Adult Intensive Care Patients.

BACKGROUND: The Withdrawal Assessment Tool-1 (WAT-1) has been validated for assessing iatrogenic withdrawal syndrome in critically ill children receiving mechanical ventilation, but little is known about this syndrome in critically ill adults. OBJECTIVE: To evaluate the validity and reliability of the WAT-1 in critically ill adults. METHODS: A prospective, observational, open-cohort pilot study of critically ill adults receiving mechanical ventilation and regular administration of opioids for at least 72 hours. Patients were assessed for withdrawal twice daily on weekdays and once daily on weekends using the WAT-1 after an opioid weaning episode. The presence of iatrogenic withdrawal syndrome was evaluated once daily using modified Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (DSM-5) criteria. All evaluations were blinded and performed independently. The criterion validity of the WAT-1 and the interrater reliability for WAT-1 and DSM-5 evaluations were determined. RESULTS: During 8 months, 52 adults (median age, 51.5 years) were enrolled. Eight patients (15%) had at least 1 positive assessment during their intensive care unit stay using the DSM-5, compared with 19 patients (37%) using the WAT-1. The overall sensitivity of the WAT-1 was 50%, and its specificity was 65.9%. Agreement between WAT-1 and DSM-5 assessments was poor (κ = 0.102). The interrater reliability for the WAT-1 was 89.1% and for the DSM-5 was 90.1%. CONCLUSION: Despite showing reliability, the WAT-1 is not a valid tool for assessing the presence of iatrogenic withdrawal syndrome in adults.

Characteristics and Outcomes of Pediatric Patients Supported With Ventricular Assist Device-A Multi-Institutional Analysis.

OBJECTIVES: The use of ventricular assist devices for pediatric patients with heart failure is increasing, but is associated with significant morbidity and mortality. Our objectives were to describe the admission outcomes and resource utilization of pediatric patients supported with ventricular assist devices, utilizing a multicenter database. DATA SOURCES: Pediatric Health Information System database (comprising 49 nonprofit children's hospitals). STUDY SELECTION: Retrospective cohort analysis of the database from January 2006 to September 2015 for all admissions less than or equal to 21 years old with ventricular assist device implantation. DATA EXTRACTION: The primary outcome was hospital mortality. The secondary outcomes were hospital length of stay and adjusted cost. DATA SYNTHESIS: We analyzed 744 ventricular assist device implantations (740 patients), 422 (57%) males, and 363 (49%) non-Hispanic white. Median age at admission was 5.9 years (interquartile range, 0.9-13.5 yr), and median length of stay was 69 days (interquartile range, 36-122 d). The overall hospital mortality was 188 (25%), whereas 395 (53%) were transplanted and 141 (19%) were discharged on ventricular assist device. Extracorporeal membrane oxygenation was used, in addition to ventricular assist device, in 340 (46%). The majority of ventricular assist device implantations (453, 61%) were from 2011 to 2015 (compared to 2006-2010). More patients discharged on ventricular assist device from 2011 to 2015 (23% vs 13% in 2006-2010; p = 0.001). There was no difference in median age, mortality, length of stay, or adjusted costs between these time periods. On multivariable analysis, underlying congenital heart disease, renal failure, liver congestion, sepsis, cerebrovascular accident, and extracorporeal membrane oxygenation were associated with hospital mortality. Sepsis and ventricular assist device replacement/repair were associated with higher adjusted cost and longer length of stay. CONCLUSIONS: The pediatric ventricular assist device experience continues to grow, with a significant increase in the number of patients undergoing ventricular assist device implantation and a higher proportion being discharged from hospital on ventricular assist device support in recent years. Underlying congenital heart disease, renal failure, sepsis, cerebrovascular accident, and extracorporeal membrane oxygenation are significantly associated with hospital mortality.

A nursing shortage - a prospect of global and local policies.

AIM: The article addresses selected determinants of the nursing shortage in Poland and other countries in the face of employee ageing. BACKGROUND: Global demographic changes have led to a systematic increase in the elderly population and a decreasing number of births, which have impacted health policy and healthcare systems in various countries. Both processes necessitate transitions in global health care. Nursing care, which has faced a human resources crisis, is a strategic area within this context. SOURCES OF EVIDENCE: This study is based on national listings and strategic documents for nursing policy in Poland, including Increasing average age of nurses and midwives prepared by the Polish Main Council of Nurses and Midwives, the incorporation of big data, international reports and a literature review on nursing and healthcare challenges. DISCUSSION/CONCLUSIONS: This paper argues that the causes of the nursing shortage are multifaceted with no single global or local measure of its nature. An overview of the problem indicates ineffective planning and use of available nursing resources, poor recruitment or an undersupply of a new staff, and global demographic conditions. The overview highlights the fact that nursing shortages have reached a critical point for healthcare services on both the local and global levels. CONCLUSIONS FOR NURSING AND HEALTH POLICY: The general recommendations for nursing policy include the need to prepare and implement national social security agendas into services provided by nurses. Such a programme would include general issues: improving working and employment conditions, implementing mechanisms regulating salary and providing the possibility of lifelong learning with the incorporation of mobile and technological innovations as a sustainable solution.

Antipsychotics for treatment of delirium in hospitalised non-ICU patients.

BACKGROUND: Guidelines suggest limited and cautious use of antipsychotics for treatment of delirium where nonpharmacological interventions have failed and symptoms remain distressing or dangerous, or both. It is unclear how well these recommendations are supported by current evidence. OBJECTIVES: Our primary objective was to assess the efficacy of antipsychotics versus nonantipsychotics or placebo on the duration of delirium in hospitalised adults. Our secondary objectives were to compare the efficacy of: 1) antipsychotics versus nonantipsychotics or placebo on delirium severity and resolution, mortality, hospital length of stay, discharge disposition, health-related quality of life, and adverse effects; and 2) atypical vs. typical antipsychotics for reducing delirium duration, severity, and resolution, hospital mortality and length of stay, discharge disposition, health-related quality of life, and adverse effects. SEARCH METHODS: We searched MEDLINE, Embase, Cochrane EBM Reviews, CINAHL, Thomson Reuters Web of Science and the Latin American and Caribbean Health Sciences Literature (LILACS) from their respective inception dates until July 2017. We also searched the Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database, Web of Science ISI Proceedings, and other grey literature. SELECTION CRITERIA: We included randomised and quasi-randomised trials comparing 1) antipsychotics to nonantipsychotics or placebo and 2) typical to atypical antipsychotics for the treatment of delirium in adult hospitalised (but not critically ill) patients. DATA COLLECTION AND ANALYSIS: We examined titles and abstracts of identified studies to determine eligibility. We extracted data independently in duplicate. Disagreements were settled by further discussion and consensus. We used risk ratios (RR) with 95% confidence intervals (CI) as a measure of treatment effect for dichotomous outcomes, and between-group standardised mean differences (SMD) with 95% CI for continuous outcomes. MAIN RESULTS: We included nine trials that recruited 727 participants. Four of the nine trials included a comparison of an antipsychotic to a nonantipsychotic drug or placebo and seven included a comparison of a typical to an atypical antipsychotic. The study populations included hospitalised medical, surgical, and palliative patients.No trial reported on duration of delirium. Antipsychotic treatment did not reduce delirium severity compared to nonantipsychotic drugs (standard mean difference (SMD) -1.08, 95% CI -2.55 to 0.39; four studies; 494 participants; very low-quality evidence); nor was there a difference between typical and atypical antipsychotics (SMD -0.17, 95% CI -0.37 to 0.02; seven studies; 542 participants; low-quality evidence). There was no evidence antipsychotics resolved delirium symptoms compared to nonantipsychotic drug regimens (RR 0.95, 95% CI 0.30 to 2.98; three studies; 247 participants; very low-quality evidence); nor was there a difference between typical and atypical antipsychotics (RR 1.10, 95% CI 0.79 to 1.52; five studies; 349 participants; low-quality evidence). The pooled results indicated that antipsychotics did not alter mortality compared to nonantipsychotic regimens (RR 1.29, 95% CI 0.73 to 2.27; three studies; 319 participants; low-quality evidence) nor was there a difference between typical and atypical antipsychotics (RR 1.71, 95% CI 0.82 to 3.35; four studies; 342 participants; low-quality evidence).No trial reported on hospital length of stay, hospital discharge disposition, or health-related quality of life. Adverse event reporting was limited and measured with inconsistent methods; in those reporting events, the number of events were low. No trial reported on physical restraint use, long-term cognitive outcomes, cerebrovascular events, or QTc prolongation (i.e. increased time in the heart's electrical cycle). Only one trial reported on arrhythmias and seizures, with no difference between typical or atypical antipsychotics. We found antipsychotics did not have a higher risk of extrapyramidal symptoms (EPS) compared to nonantipsychotic drugs (RR 1.70, 95% CI 0.04 to 65.57; three studies; 247 participants; very-low quality evidence); pooled results showed no increased risk of EPS with typical antipsychotics compared to atypical antipsychotics (RR 12.16, 95% CI 0.55 to 269.52; two studies; 198 participants; very low-quality evidence). AUTHORS' CONCLUSIONS: There were no reported data to determine whether antipsychotics altered the duration of delirium, length of hospital stay, discharge disposition, or health-related quality of life as studies did not report on these outcomes. From the poor quality data available, we found antipsychotics did not reduce delirium severity, resolve symptoms, or alter mortality. Adverse effects were poorly or rarely reported in the trials. Extrapyramidal symptoms were not more frequent with antipsychotics compared to nonantipsychotic drug regimens, and no different for typical compared to atypical antipsychotics.

Iatrogenic Opioid Withdrawal in Critically Ill Patients: A Review of Assessment Tools and Management.

OBJECTIVE: To (1) provide an overview of the epidemiology, clinical presentation, and risk factors of iatrogenic opioid withdrawal in critically ill patients and (2) conduct a literature review of assessment and management of iatrogenic opioid withdrawal in critically ill patients. DATA SOURCES: We searched MEDLINE (1946-June 2017), EMBASE (1974-June 2017), and CINAHL (1982-June 2017) with the terms opioid withdrawal, opioid, opiate, critical care, critically ill, assessment tool, scale, taper, weaning, and management. Reference list of identified literature was searched for additional references as well as www.clinicaltrials.gov . STUDY SELECTION AND DATA EXTRACTION: We restricted articles to those in English and dealing with humans. DATA SYNTHESIS: We identified 2 validated pediatric critically ill opioid withdrawal assessment tools: (1) Withdrawal Assessment Tool-Version 1 (WAT-1) and (2) Sophia Observation Withdrawal Symptoms Scale (SOS). Neither tool differentiated between opioid and benzodiazepine withdrawal. WAT-1 was evaluated in critically ill adults but not found to be valid. No other adult tool was identified. For management, we identified 5 randomized controlled trials, 2 prospective studies, and 2 systematic reviews. Most studies were small and only 2 studies utilized a validated assessment tool. Enteral methadone, α-2 agonists, and protocolized weaning were studied. CONCLUSION: We identified 2 validated assessment tools for pediatric intensive care unit patients; no valid tool for adults. Management strategies tested in small trials included methadone, α-2 agonists, and protocolized sedation/weaning. We challenge researchers to create validated tools assessing specifically for opioid withdrawal in critically ill children and adults to direct management.

Reliability of echocardiographic speckle-tracking derived bi-atrial strain assessment under different hemodynamic conditions.

The aim of this study was to assess intra- and inter-observer variability of left (LA) and right atrial (RA) strain indices obtained by two-dimensional speckle-tracking echocardiography (2D-STE) in a healthy group of individuals at low-altitude and after rapid ascent to high-altitude in order to provoke altered systemic and pulmonary hemodynamics otherwise seen in various cardiac diseases. Twenty healthy subjects underwent transthoracic echocardiography during a baseline examination at low-altitude (424 m) as well as 7, 20 and 44 h after arrival at high-altitude (4559 m). Atrial strain indices (i.e. reservoir, conduit and contractile strain) were determined off-line by two independent observers. Intra- and inter-observer reproducibility of variables was assessed by intra-class correlation coefficients (ICCs), coefficients of variation and Bland Altman plots. Heart rate, systemic blood pressure and pulmonary artery pressure increased significantly from low-altitude to the first examination at high-altitude. Intra-observer ICCs were ≥0.90 except for RA conduit strain with an ICC of 0.86. The mean intra-observer differences were small and limits of agreement of relative differences were narrow for all atrial strain parameters (<3 and <16%, respectively). Inter-observer ICCs (0.80-0.90), mean biases and limits of agreement (<4 and <20%, respectively) were greater than intra-observer results for all parameters. Intra- and inter-obserer ICCs for all atrial strain variables did not differ between low- and high-altitude. 2D-STE-derived bi-atrial strain indices have excellent intra- and moderate inter-observer reproducibility with no effect of high-altitude-induced hemodynamic changes on reliability results.

Do Wellness Tourists Get Well? An Observational Study of Multiple Dimensions of Health and Well-Being After a Week-Long Retreat.

BACKGROUND: Wellness retreats use many complementary and alternative therapies within a holistic residential setting, yet few studies have evaluated the effect of retreat experiences on multiple dimensions of health and well-being, and no published studies have reported health outcomes in wellness tourists. OBJECTIVES: To assess the effect of a week-long wellness-retreat experience in wellness tourists. DESIGN: A longitudinal observational study with outcomes assessed upon arrival and departure and 6 weeks after the retreat. SETTING: A rural health retreat in Queensland, Australia. INTERVENTIONS: A holistic, 1-week, residential, retreat experience that included many educational, therapeutic, and leisure activities and an organic, mostly plant-based diet. OUTCOME MEASURES: Multiple outcome measures were performed upon arrival and departure and 6 weeks after the retreat. These included anthropometric measures, urinary pesticide metabolites, a food and health symptom questionnaire, the Five Factor Wellness Inventory, the General Self Efficacy questionnaire, the Pittsburgh Insomnia Rating Scale, the Depression Anxiety Stress Scale, the Profile of Mood States, and the Cogstate cognitive function test battery. RESULTS: Statistically significant improvements (p < 0.05) were seen in almost all measures (n = 37) after 1 week and were sustained at 6 weeks (n = 17). There were statistically significant improvements (p < 0.001) in all anthropometric measures after 1 week, with reductions in abdominal girth (2.7 cm), weight (1.6 kg), and average systolic and diastolic pressure (-16.1 mmHg and -9.3 mmHg, respectively). Statistically significant improvements (p < 0.05) were also seen in psychological and health symptom measures. Urinary pesticide metabolites were detected in pooled urine samples before the retreat and were undetectable after the retreat. CONCLUSION: Retreat experiences can lead to substantial improvements in multiple dimensions of health and well-being that are maintained for 6 weeks. Further research that includes objective biomarkers and economic measures in different populations is required to determine the mechanisms of these effects and assess the value and relevance of retreat experiences to clinicians and health insurers.

Initial planning benefits complex prospective memory at a cost.

The effect of initial planning on complex prospective memory was investigated using a virtual environment and a sample of healthy young adults (N = 34). Participants were assigned to either an initial planning or a control condition and were asked to complete a series of time- and event-based prospective memory tasks. The planning group completed the tasks more quickly and accurately than the control group. However, the total time spent, including both planning and task execution, was comparable for the two groups. Within the planning group, tasks that were planned were more likely to be completed than unplanned tasks, but inclusion of overly detailed information in the plans resulted in poorer performance. These results suggest that although initial planning can be beneficial to task completion, the complexity of a plan may contribute to decrements in performance.

Critical Assessment of Protein Cross-Linking and Molecular Docking: An Updated Model for the Interaction Between Photosystem II and Psb27.

Photosystem II (PSII) is a large membrane-protein complex composed of about 20 subunits and various cofactors, which mediates the light-driven oxidation of water and reduction of plastoquinone, and is part of the photosynthetic electron transfer chain that is localized in the thylakoid membrane of cyanobacteria, algae, and plants. The stepwise assembly of PSII is guided and facilitated by numerous auxiliary proteins that play specific roles in this spatiotemporal process. Psb27, a small protein localized in the thylakoid lumen, appears to associate with an intermediate PSII complex that is involved in assembly of the Mn4CaO5 cluster. Its precise binding position on the PSII intermediate remains elusive, as previous approaches to the localization of Psb27 on PSII have yielded contradictory results. This was our motivation for a critical assessment of previously used methods and the development of an improved analysis pipeline. The combination of chemical cross-linking and mass spectrometry (CX-MS) with isotope-coded cross-linkers was refined and validated with reference to the PSII crystal structure. Psb27 was localized on the PSII surface adjacent to the large lumenal domain of CP43 on the basis of a cross-link connecting Psb27-K91 to CP43-K381. Additional contacts associating Psb27 with CP47 and the C-termini of D1 and D2 were detected by surface plasmon resonance (SPR) spectroscopy. This information was used to model the binding of Psb27 to the PSII surface in a region that is occupied by PsbV in the mature complex.

Environmental Chemical Assessment in Clinical Practice: Unveiling the Elephant in the Room.

A growing body of evidence suggests chemicals present in air, water, soil, food, building materials and household products are toxicants that contribute to the many chronic diseases typically seen in routine medical practice. Yet, despite calls from numerous organisations to provide clinicians with more training and awareness in environmental health, there are multiple barriers to the clinical assessment of toxic environmental exposures. Recent developments in the fields of systems biology, innovative breakthroughs in biomedical research encompassing the "-omics" fields, and advances in mobile sensing, peer-to-peer networks and big data, provide tools that future clinicians can use to assess environmental chemical exposures in their patients. There is also a need for concerted action at all levels, including actions by individual patients, clinicians, medical educators, regulators, government and non-government organisations, corporations and the wider civil society, to understand the "exposome" and minimise the extent of toxic exposures on current and future generations. Clinical environmental chemical risk assessment may provide a bridge between multiple disciplines that uses new technologies to herald in a new era in personalised medicine that unites clinicians, patients and civil society in the quest to understand and master the links between the environment and human health.

Reliability assessment of the endoscopic examination in patients with allergic rhinitis.

OBJECTIVE: To study if nasal endoscope can be a reliable tool in assessing patients with allergic rhinitis. MATERIALS AND METHODS: A prospective study. Patients who were diagnosed with allergic rhinitis underwent a nasal endoscopic examination performed by two physicians blinded to the scoring of each other. A correlation was made among symptom severity, endoscopic findings, and interrater variability. RESULTS: Ninety patients were included in the study: 34 patients had mild disease and 56 had moderate-to-severe allergic rhinitis according to the Allergic Rhinitis and its Impact on Asthma guidelines. Increases in mucosal edema and bluish discoloration were predictive of the severity of allergic rhinitis disease (p < 0.05). The presence of nasal secretions was not predictive of allergic rhinitis. Interrater reliability was fair for mucosal edema, moderate-to-almost perfect for the rest of the endoscopic findings. CONCLUSION: Nasal endoscopy may reveal signs that are predictive of the severity of allergic rhinitis. A detailed checklist is needed for the nasal endoscopic examination to decrease interrater variability.

Tracing the ingredients for a habitable earth from interstellar space through planet formation.

We use the C/N ratio as a monitor of the delivery of key ingredients of life to nascent terrestrial worlds. Total elemental C and N contents, and their ratio, are examined for the interstellar medium, comets, chondritic meteorites, and terrestrial planets; we include an updated estimate for the bulk silicate Earth (C/N = 49.0 ± 9.3). Using a kinetic model of disk chemistry, and the sublimation/condensation temperatures of primitive molecules, we suggest that organic ices and macromolecular (refractory or carbonaceous dust) organic material are the likely initial C and N carriers. Chemical reactions in the disk can produce nebular C/N ratios of ∼1-12, comparable to those of comets and the low end estimated for planetesimals. An increase of the C/N ratio is traced between volatile-rich pristine bodies and larger volatile-depleted objects subjected to thermal/accretional metamorphism. The C/N ratios of the dominant materials accreted to terrestrial planets should therefore be higher than those seen in carbonaceous chondrites or comets. During planetary formation, we explore scenarios leading to further volatile loss and associated C/N variations owing to core formation and atmospheric escape. Key processes include relative enrichment of nitrogen in the atmosphere and preferential sequestration of carbon by the core. The high C/N bulk silicate Earth ratio therefore is best satisfied by accretion of thermally processed objects followed by large-scale atmospheric loss. These two effects must be more profound if volatile sequestration in the core is effective. The stochastic nature of these processes hints that the surface/atmospheric abundances of biosphere-essential materials will likely be variable.

Isolation of PCR quality microbial community DNA from heavily contaminated environments.

Asphalts, biochemically degraded oil, contain persistent, water-soluble compounds that pose a significant challenge to the isolation of PCR quality DNA. The adaptation of existing DNA purification protocols and commercial kits proved unsuccessful at overcoming this hurdle. Treatment of aqueous asphalt extracts with a polyamide resin afforded genomic microbial DNA templates that could readily be amplified by PCR. Physicochemically distinct asphalt samples from five natural oil seeps successfully generated the expected 291 bp amplicons targeting a region of the 16S rRNA gene, illustrating the robustness of the method. DNA recovery yields were in the 50-80% range depending on how the asphalt sample was seeded with exogenous DNA. The scope of the new method was expanded to include soil with high humic acid content. DNA from soil samples spiked with a range of humic acid concentrations was extracted with a commercial kit followed by treatment with the polyamide resin. The additional step significantly improved the purity of the DNA templates, especially at high humic acid concentrations, based on qPCR analysis of the bacterial 16S rRNA genes. The new method has the advantages of being inexpensive, simple, and rapid and should provide a valuable addition to protocols in the field of petroleum and soil microbiology.

Nanoflow electrospinning serial femtosecond crystallography.

An electrospun liquid microjet has been developed that delivers protein microcrystal suspensions at flow rates of 0.14-3.1 µl min(-1) to perform serial femtosecond crystallography (SFX) studies with X-ray lasers. Thermolysin microcrystals flowed at 0.17 µl min(-1) and diffracted to beyond 4 Å resolution, producing 14,000 indexable diffraction patterns, or four per second, from 140 µg of protein. Nanoflow electrospinning extends SFX to biological samples that necessitate minimal sample consumption.

Head-centric disparity and epipolar geometry estimation from a population of binocular energy neurons.

We present a hybrid neural network architecture that supports the estimation of binocular disparity in a cyclopean, head-centric coordinate system without explicitly establishing retinal correspondences. Instead the responses of binocular energy neurons are gain-modulated by oculomotor signals. The network can handle the full six degrees of freedom of binocular gaze and operates directly on image pairs of possibly varying contrast. Furthermore, we show that in the absence of an oculomotor signal the same architecture is capable of estimating the epipolar geometry directly from the population response. The increased complexity of the scenarios considered in this work provides an important step towards the application of computational models centered on gain modulation mechanisms in real-world robotic applications. The proposed network is shown to outperform a standard computer vision technique on a disparity estimation task involving real-world stereo images.