bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Learning Teams Versus Root Cause Analysis for Incident Investigation in a Large United Kingdom National Health Service Hospital
Authors: Robbins Tim , Tipper Stephen , King Justin , Ramachandran Satya Krishna , Pandit Jaideep J. , Pandit Meghana
Published: March 2020

Introduction

Significant resource is invested into investigation of adverse healthcare events. Outcomes of such investigations have varying degrees of effectiveness. The “hierarchy of effectiveness” model proposes system-focused changes have greater impact than person-focused actions. The traditional approach to investigation is root cause analysis (RCA); however, such an approach does not prioritize system-focused action generation. Learning team-based investigations are thought to generate more effective system-focused actions; however, this has not been evaluated.

Methods

Retrospective mixed methods evaluation of learning teams compared with RCA. Twenty-two learning team investigations compared with 22 RCA investigations, with quantitative assessment of the number of system-focused and person-focused actions generated. Assignment of the two different methods to incidents was not random, with learning teams being selected for cases, which were initially judged to be process-focused problems. Semistructured interviews were conducted with four learning team facilitators with thematic analysis to identify causes for outcome variations.

Results

Learning team investigations yielded a median of 7.5 actions compared with 3.5 actions for RCA: 57% of learning team actions were system focused versus 30% for RCA. We identified variations in personnel involved, culture of the investigation, and differences in the investigative approaches as potential drivers for these differences.

Conclusions

We observed that learning team investigations that targeted process-focused problems generated more actions and a higher number of system-focused actions. There is a difference in culture created during learning team investigations. Although learning teams are not suitable for all investigations, they represent a readily reproducible and valuable addition to the investigative toolkit.
Harm Prevalence Due to Medication Errors Involving High-Alert Medications: A Systematic Review
Authors: Sodré Alves Bárbara Manuella Cardoso , de Andrade Tâmara Natasha Gonzaga , Cerqueira Santos Sabrina , Goes Aline Santana , Santos Adriano da Silva , Lyra Júnior Divaldo Pereira de , de Oliveira Filho Alfredo Dias
Published: March 2020

Objective

The aim of the study was to determine the prevalence and main types of harm caused by high-alert medication after medication errors (MEs) in hospitals.

Method

A literature systematic review was conducted on PubMed, Scopus, Web of Science, and Lilacs. Eligible studies published until June 2017 were included.

Result

Of 6244 studies identified through searching four electronic databases, five studies meeting the selection criteria of this study were analyzed. There was wide variation in the overall prevalence of harm due to MEs involving HAM, from 3.8% to 100%, whereas the pooled prevalence was 16.3%. Overall, 0.01% of harm caused by MEs involving HAM resulted in death. The severity of errors ranged from 0.1% to 19.2% for moderate errors, 0.2% to 15.4% for serious errors, and 1.9% lethal to the patients. The highest prevalences of harm occurred after errors involving potassium chloride 15%, insulin, and epoprostenol. The lowest prevalence of harm was related to errors of anticoagulants administration. The methodological heterogeneity limited direct comparisons among the studies.

Conclusions

Of the 15 drugs on the list of Institute for Safe Medication Practices HAMs in the United States and Brazil, nine did not present scientific evidence of the potential for harm. In general, few studies, characterized by methodological and conceptual heterogeneity, were performed to determine the harm prevalence resulting from errors involving these drugs.
Prospective, Blinded Evaluation of Template-Based Cesarean Documentation Error in an Obstetric Training Program
Authors: Perez William M. , Babbar Shilpa , Vricella Laura K.
Published: March 2020

Objective

Cesarean operative report accuracy impacts postoperative care and future obstetric decision-making. The impact of electronic health record template use on cesarean documentation error remains unknown. The aim of the study was to describe the incidence of resident physician documentation error in cesarean operative reports using electronic health record templates.

Methods

Attending physicians completed a standardized audit form after cesarean deliveries, which was compared with the resident operative report. Resident physicians were blinded to the auditing process. Errors were classified as none, major, or minor using predefined definitions. Author and operative characteristics were collected for comparative and predictive analyses. Data were analyzed by presence or absence of error.

Results

We reviewed 100 cesarean operative reports. Major and minor errors were encountered in 33% and 53% of operative notes, respectively. Advancing training level was associated with lower incidence of major error (50%, for postgraduate year [PGY] 1, 33% for PGY 2, and 0% for PGY 3/4, P = 0.02), but minor errors were similar among training level, P = 0.48. Operative duration, documentation interval, and shift characteristics were similar in cases with and without documentation errors. In multiple logistic regression, PGY was predictive of major documentation error (adjusted odds ratio = 0.39, 95% confidence interval = 0.17–0.92).

Conclusions

A high incidence of clinically significant documentation error was observed in a residency training program using standardized templates for cesarean operative reports. Incidence of major error decreased with increasing training, but minor error was similar across levels of training. These data suggest that measures should be taken to improve documentation accuracy in medical training to provide optimal obstetric care.
The Impact of Resident Holdover Admissions on Length of Hospital Stay and Risk of Transfer to an Intensive Care Unit
Authors: Ashana Deepshikha Charan , Chan Vincent K. , Vangala Sitaram , Bell Douglas S.
Published: March 2020

Objective

Implementation of residency duty hour standards has led to adoption of different staffing models, such as the “holdover” model, whereby nighttime teams admit patients and transfer their care to daytime teams who provide ongoing care. In contrast, nonholdover teams at our institution are responsible for both admitting patients and providing ongoing care. We sought to determine whether patients admitted by holdover teams experience worse outcomes than those admitted by nonholdover teams.

Methods

This is a retrospective cohort study of patients admitted to the internal medicine hospital service at a quaternary care hospital from July 2013 to June 2015. Primary outcomes included hospital length of stay (LOS) and transfer to an intensive care unit within 72 hours of admission. Secondary outcomes were any transfer to an intensive care unit, in-hospital mortality, discharge to home (versus discharge to postacute care facility), and readmission to the health system within 30 days of discharge.

Results

We analyzed 5518 encounters, 64% of which were admitted by a holdover team. Outcomes were similar between study groups, except the LOS, which was 5.5 hours longer for holdover encounters in unadjusted analyses (5.18 versus 4.95 days, P = 0.04) but not significantly different in adjusted analyses. The mean discharge time was 4:00 p.m. for both groups, whereas the mean admission times were 12:00 a.m. and 4:00 p.m. for holdover and nonholdover encounters, respectively.

Conclusions

Holdover encounters at our institution were not associated with worse patient safety outcomes. A small increase in LOS may have been attributable to holdover patients having earlier admission and identical discharge times.
Self-Reported Neurotoxic Symptoms in Hip Arthroplasty Patients With Highly Elevated Blood Cobalt: A Case-Control Study
Authors: Swiatkowska Ilona , Henckel Johann , Sabah Shiraz A. , Hart Alister J.
Published: March 2020

Objectives

This study aimed to investigate the prevalence of self-reported neurotoxicity and cognitive defects in hip replacement patients with markedly raised blood cobalt.

Methods

Case group comprised 53 patients with metal-on-metal (MoM) implants and a history of blood Co ≥20 μg/L for a median of 3 years (interquartile range, 2–5 years). The control group comprised 53 patients with ceramic-on-ceramic prostheses and blood Co <1 μg/L. Median age was 67 years (interquartile range, 60–74 years). The participants completed the Neurotoxic Symptom Checklist-60, Diabetic Neuropathy Score, Douleur Neuropathique-10, and Systemic Symptom Checklist, and underwent the Mini-Mental State Examination.

Results

The MoM and ceramic-on-ceramic groups were compared, the results were as follows: Neurotoxic Symptom Checklist-60 (median): cognitive defects (2.0 versus 1.9; P = 0.002), chest complaints (1.3 versus 1.3; P = 0.042), balance disturbances (1.3 versus 1.0; P < 0.001), sleep disturbances (2.7 versus 2.0; P = 0.004), mood disorders (2.0 versus 1.5; P = 0.001), sensorimotor disorders (1.6 versus 1.2; P < 0.001), physical complaints (2.0 versus 1.4; P = 0.009), fatigue (2.0 versus 1.6; P = 0.001), and total score (108 versus 90; P < 0.001); abnormal Diabetic Neuropathy Score/Douleur Neuropathique-10 (%): 60.3/13.2 versus 24.5/1.9 (P < 0.001/P = 0.028). Systemic Symptom Checklist (in percent): feeling cold (37.7 versus 17; P = 0.01), weight gain (18.9 versus 1.9; P = 0.008), metallic taste (26.4 versus 3.8; P = 0.002), worsening eyesight (37.7 versus 15.1; P = 0.008) and hearing (24.5 versus 7.5; 0.032), ankle swelling (32.1 versus 7.5; P = 0.002), shortness of breath on exertion (9.4 versus 5.7; P = 0.015), and generalized rash (28.3 versus 7.5; P = 0.01); and Mini-Mental State Examination (median): 29 versus 30 (P = 0.017). Patients in the MoM group were aware of their high cobalt levels and displayed a higher tendency to overreport symptoms (P < 0.001), which could have contributed to the higher scores.

Conclusions

Frequency of reporting a number of symptoms was markedly higher in MoM patients, but clinically significant neurotoxicity was not observed (possibly due to the short exposure to elevated cobalt). Patients with repeated blood Co ≥20 μg/L measurements should be questioned about possible systemic health complaints at follow-up.
Hospital Adverse Event Reporting Systems: A Systematic Scoping Review of Qualitative and Quantitative Evidence
Authors: Estrada-Orozco Kelly , Cantor Cruz Francy , Benavides Cruz Johana , Ruiz-Cardozo Miguel Angel , Suárez-Chacón Andrea Marcela , Cortés Tribaldos Jhon Alexánder , Chaparro Rojas Miguel Alejandro , Rojas Contreras Ricardo Andrés , González-Camargo Juan Esteban , González Berdugo Juan Camilo , Villate-Soto Steffany Lorena , Moreno-Chaparro Jaime , García López Andrea , Aristizábal Robayo María Fernanda , Bonilla Regalado Iván Andrés , Castro Barreto Nathaly Liliana , Ceballos-Inga Leydi , Gaitán-Duarte Hernando
Published: March 2020

Introduction

Reducing the incidence of reportable events with undesirable effects (REUE) is a priority in the hospital environment, which is why reporting systems have been implemented to identify and manage them. Information is required regarding the performance of reporting systems, barriers, or facilitators for reporting and strategies that improve passive reporting.

Methodology

Systematic scoping review of the literature that included studies performed in the population exposed to the occurrence of REUE in the health system (teams, patients, and family). A search was performed in Cochrane Database of Systematic Reviews, Epistemonikos, MEDLINE (PubMed), MEDLINE In-Process and MEDLINE Daily Update, EMBASE, LILACS, and databases of the World Health Organization and Pan-American Health Organization.

Results

Fifteen studies were found, 1 systematic review, 2 clinical trials, 8 observational studies, 3 qualitative studies, and 1 mixed study. In 4 of them, the effectiveness of active versus passive reporting systems was compared. The measures to improve the passive systems were education about REUE, simplification of the reporting format, activities focused on increasing the motivation for self-report, adoption of self-report as an obligatory institutional policy, and using specific report formats for each service.

Conclusions

There is information that allows to find differences between the performance of the active and passive reporting systems. The reviewed research articles found that passive techniques significantly underreported adverse events. It is recommended that institutions adopt both active and passive techniques in adverse event surveillance. New studies should be directed to answer the comparative efficiency of the reporting systems.
Do Patients and Relatives Have Different Dispositions When Challenging Healthcare Professionals About Patient Safety? Results Before and After an Educational Program
Authors: Rodrigo‐Rincon Isabel , Irigoyen-Aristorena Isabel , Tirapu-Leon Belen , Zaballos-Barcala Nicolás , Sarobe-Carricas Maite , Antelo-Caamaño May , Lobo-Palanco Joaquín , Martin-Vizcaino Marta
Published: March 2020

Background

There is a universal interest in evaluating the new roles of patients to improve patient safety. However, relatively little is known about the contribution of family caregivers. The purposes of this study was to determine whether patients and relatives (P&Rs) have different dispositions when challenging healthcare professionals about patient safety and to measure the influence of an educational program.

Methods

An interventional before-and-after design was used to determine the P&Rs’ basal level of willingness and the influence of a training program. One hundred thirty-six participants were recruited, 90 patients and 46 relatives, from the Day Hospital of a Tertiary Hospital in Spain, in 2018.

The safe practices selected were as follows: patient identification, hand hygiene, blood or chemotherapy identification, and secondary effects of treatment. The educational materials comprised brochures and story-type videos. A questionnaire measured participants’ willingness to speak up before and after the training.

Results

One hundred thirty-six P&Rs (63% response rate) agreed to participate. The hypothesis that relatives are more willing to challenge healthcare professionals could not be proven. Their willingness to speak up depended on the type of safe practice both before and after training, ranging from 42% to 87%. The percentage of items that P&Rs were willing to challenge increased after the training among both the patients and the relatives, but statically significant differences were only seen among patients.

Conclusions

After the training, participants’ willingness to challenge healthcare workers was high for all safe practices analyzed but hand hygiene. Patients and relatives had very similar willingness. After the training, participants felt confident with their knowledge about safe practices, thereby increasing their challenging attitude.
The Effect of Clinical Volume on Annual and Per-Patient Encounter Medical Malpractice Claims Risk
Authors: Schaffer Adam C. , Babayan Astrid , Yu-Moe Chihwen Winnie , Sato Luke , Einbinder Jonathan S.
Published: March 2020

Objectives

The relationship between medical malpractice risk and one of the fundamental characteristics of physician practice, clinical volume, remains undefined. This study examined how the annual and per-patient encounter medical malpractice claims risk varies with clinical volume.

Methods

Clinical volume was determined using health insurance charges and was linked at the physician level to malpractice claims data from a malpractice insurer. The annual medical malpractice claims risk was expressed as the percent of physicians with a malpractice claim, and the per-encounter medical malpractice claims risk was expressed as malpractice claims per 1000 patient encounters. Both of these malpractice claims risk metrics were analyzed as a function of clinical volume, using linear and spline regression.

Results

As clinical volume increased, the percent of physicians with a malpractice claim increased linearly. Among all physicians studied, for each decile increase in clinical volume, there was a 0.373% increase in physicians with a malpractice claim (95% confidence interval, 0.301%–0.446%; P < 0.0001). As clinical volume increased, the rate of malpractice claims per 1000 patient encounters decreased. This relationship between clinical volume and per-encounter claims risk was nonlinear. There was a clinical volume threshold, below which decreasing clinical volume was associated with increasing per-encounter claims risk, and above which claims risk no longer significantly varied with increases in clinical volume.

Conclusions

Clinical volume is a crucial determinant of physician malpractice risk, with higher-volume physicians having higher annual risk but lower per-encounter risk. Clinical volume data should be incorporated into analyses of malpractice risk.
Impact of marijuana on venous thromboembolic events: Cannabinoids cause clots in trauma patients
Authors: Stupinski Jack , Bible Letitia , Asmar Samer , Chehab Mohamad , Douglas Molly , Ditillo Michael , Gries Lynn , Khurrum Muhammad , Joseph Bellal
Published: March 2020

BACKGROUND

Tetrahydrocannabinoids (THC) can modulate the coagulation cascade resulting in hypercoagulability. However, the clinical relevance of these findings has not been investigated. The aim of our study was to evaluate the impact of preinjury marijuana exposure on thromboembolic complications (TEC) in trauma patients.

METHODS

We performed a 2-year (2015–2016) analysis of American College of Surgeons Trauma Quality and Improvement Program database and included all adult (≥18 year) trauma patients. Patients were stratified based on preinjury exposure to Marijuana: THC + ve and THC −ve groups. We performed propensity score matching to control for confounding variables: demographics, comorbidities, injury parameters, hospital course, and thromboprophylaxis use. Outcomes were TEC (deep venous thrombosis, pulmonary embolism, stroke, myocardial infarction) and mortality.

RESULTS

Of 593,818 trauma patients, 678 patients were matched (THC + ve: 226 vs. THC −ve: 452). Mean age was 34 ± 15 years, Injury Severity Score was 14 (10–21). There was no difference between the two groups regarding age (p =0.75), sex (p =0.99), Injury Severity Score (p =0.54), spine Abbreviated Injury Scale (AIS) (p =0.61), head AIS (p = 0.32), extremities AIS (p =0.38), use of unfractionated heparin (p =0.54), use of low molecular weight heparin (p = 0.54), and hospital length of stay (p =0.87). Overall, the rate of TEC was 4.3% and mortality was 4%. Patients in THC + ve group had higher rates of TEC compared with those in THC −ve group (3.5% vs. 1.1%,p =0.03). The rate of deep venous thrombosis (6.6% vs. 1.8%,p= 0.02) and PE (2.2% vs. 0.2%,p =0.04) was higher in THC + ve group. However, there was no difference regarding the rate of stroke (p =0.24), myocardial infarction (p= 0.35) and mortality (p =0.28).

CONCLUSION

THC exposure increases the risk of TEC in patients with trauma. Early identification and treatment for TEC is required to improve outcomes in this high-risk subset of trauma patients.

LEVEL OF EVIDENCE

Prognostic study, level III.
Low costs of adaptation to dietary restriction
Authors: Moger-Reischer Roy Z. , Snider Elizabeth V. , McKenzie Kelsey L. , Lennon Jay T.
Published: March 2020

Dietary restriction (DR) is the most successful and widespread means of extending organismal lifespan. However, the evolutionary basis of life extension under DR remains uncertain. The traditional evolutionary explanation is that when organisms experience DR, they allocate endogenous resources to survival and postpone reproduction until conditions improve. However, this life-extension strategy should be maladaptive if DR continues for multiple generations due to trade-offs between longevity and reproduction. To test this prediction, we subjected the budding yeast
Saccharomyces cerevisiae
to 1800 generations of evolution on restricted versus non-restricted diets. Adaptation to a non-restricted diet improved reproductive fitness by 57%, but provided a much smaller (14%) advantage on a restricted diet. By contrast, adaptation to DR resulted in an approximately 35% increase in reproductive fitness on both restricted and non-restricted diets. Importantly, the life-extending effect of DR did not decrease following long-term evolution on the restricted diet. Thus, contrary to theoretical expectations, we found no evidence that the life-extending DR response became maladaptive during multigenerational DR. Together, our results suggest that the DR response has a low cost and that this phenomenon may have evolved as part of a generalist strategy that extends beyond the benefits of postponing reproduction.
David Chandler. 15 October 1944—18 April 2017
Authors: Andersen Hans C. , Chakraborty Arup K. , Weeks John D.
Published: March 2020

David Chandler, a major figure in statistical mechanics, spent his career at the University of Illinois Urbana-Champaign, the University of Pennsylvania and the University of California Berkeley. Starting in his graduate work, he made significant advances in many areas of statistical mechanics theory, such as the structure and thermodynamics of simple liquids and nonpolar molecular liquids, the nature of hydrophobic hydration and hydrophobic interactions in aqueous systems, chemical reaction rates, quantum processes in liquids such as electron transfer and the solvation of an excess electron in water, ‘transition path sampling’ (a method for using computer simulations to study chemical reaction rates and other dynamic processes in liquids), and the ‘dynamic facilitation’ theory of the properties of supercooled liquids and the glass transition. He received the Hildebrand Award and the Theoretical Chemistry Award from the American Chemical Society and the Irving Langmuir Chemical Physics Award from the American Physical Society. He was elected to membership in the US National Academy of Sciences and the American Academy of Arts and Sciences.
Combiningin silicoandin vitromodels to inform cell seeding strategies in tissue engineering
Authors: Coy R. , Al-Badri G. , Kayal C. , O'Rourke C. , Kingham P. J. , Phillips J. B. , Shipley R. J.
Published: March 2020

The seeding density of therapeutic cells in engineered tissue impacts both cell survival and vascularization. Excessively high seeded cell densities can result in increased death and thus waste of valuable cells, whereas lower seeded cell densities may not provide sufficient support for the tissuein vivo, reducing efficacy. Additionally, the production of growth factors by therapeutic cells in low oxygen environments offers a way of generating growth factor gradients, which are important for vascularization, but hypoxia can also induce unwanted levels of cell death. This is a complex problem that lends itself to a combination of computational modelling and experimentation. Here, we present a spatio-temporal mathematical model parametrized usingin vitrodata capable of simulating the interactions between a therapeutic cell population, oxygen concentrations and vascular endothelial growth factor (VEGF) concentrations in engineered tissues. Simulations of collagen nerve repair constructs suggest that specific seeded cell densities and non-uniform spatial distributions of seeded cells could enhance cell survival and the generation of VEGF gradients. These predictions can now be tested using targeted experiments.
Environmental perturbations induce correlations in midge swarms
Authors: van der Vaart Kasper , Sinhuber Michael , Reynolds Andrew M. , Ouellette Nicholas T.
Published: March 2020

Although collectively behaving animal groups often show large-scale order (such as in bird flocks), they need not always (such as in insect swarms). It has been suggested that the signature of collective behaviour in disordered groups is a residual long-range correlation. However, results in the literature have reported contradictory results as to the presence of long-range correlation in insect swarms, with swarms in the wild displaying correlation but those in a controlled laboratory environment not. We resolve these apparently incompatible results by showing that the external perturbations generically induce the emergence of correlations. We apply a range of different external stimuli to laboratory swarms of the non-biting midge
Chironomus riparius
, and show that in all cases correlations appear when perturbations are introduced. We confirm the generic nature of these results by showing that they can be reproduced in a stochastic model of swarms. Given that swarms in the wild will always have to contend with environmental stimuli, our results thus harmonize previous findings. These findings emphasize that collective behaviour cannot be understood in isolation without considering its environmental context, and that new research is needed to disentangle the distinct roles of intrinsic dynamics and external stimuli.
Daniel Hanbury's Study of Chinese
MATERIA MEDICA
: A British Network of Letters and Specimens during the Nineteenth Century
Authors: An Sooyoung
Published: March 2020

This article focuses on British scientist Daniel Hanbury and his extensive network of correspondence and research practices concerning Chinese
materia medica
. As a researcher motivated by the need for knowledge of various natural materials for their commercial value, Hanbury's academic career benefited primarily from his extensive correspondence. By controlling his own network of plant acquisition and interchange, he mobilized numerous individuals and organized the network to collect specimens, drug samples, and various forms of information and send them to London. As the British commercial empire expanded, so too did Hanbury's network grow to include many collectors who were allowed to enter an increasing number of Chinese port cities, which entailed notable opportunities and challenges. By paying attention to the details of Hanbury's strategies and efforts to ensure that the collaboration in China conformed to the changing definition of ‘scientific knowledge’ of drugs, the article sheds light on how the practice of relying on the transnational botanical network was executed in the context of nineteenth-century research on foreign
materia medica
.
2019 Wilkins–Bernal–Medawar lectureLife begins at 40: the demographic and cultural roots of the midlife crisis
Authors: Jackson Mark
Published: March 2020

In 1965, the psychoanalyst and social scientist Elliott Jaques introduced a term, the ‘midlife crisis’, that continues to structure Western understandings and experiences of middle age. Following Jaques's work, the midlife crisis became a popular means of describing how—and why—men and women around the age of 40 became disillusioned with work, disenchanted with relationships and detached from family responsibilities. Post-war sociological and psychological studies of middle age regarded the midlife crisis as a manifestation of either biological or psychological change, as a moment in the life course when—perhaps for the first time—people felt themselves to be declining towards death. Although the midlife crisis has often been dismissed as a myth or satirized in novels and films, the concept has persisted not only in stereotypical depictions of rebellion and infidelity at midlife, but also in research that has sought to explain the particular social, physical and emotional challenges of middle age. In the spirit of the pioneering research of John Wilkins, John Bernal and Peter Medawar, each of whom in different ways emphasized the complex interrelations between science and society, I want to argue that the emergence of the midlife crisis—as concept and experience—during the middle decades of the twentieth century was not coincidental. Rather it was the product of historically specific demographic changes and political aspirations—at least in the Western world—to keep alive the American dream of economic progress and material prosperity.
The multifaceted role of vitamin B
6
in cancer:
Drosophila
as a model system to investigate DNA damage
Authors: Contestabile Roberto , di Salvo Martino Luigi , Bunik Victoria , Tramonti Angela , Vernì Fiammetta
Published: March 2020

A perturbed uptake of micronutrients, such as minerals and vitamins, impacts on different human diseases, including cancer and neurological disorders. Several data converge towards a crucial role played by many micronutrients in genome integrity maintenance and in the establishment of a correct DNA methylation pattern. Failure in the proper accomplishment of these processes accelerates senescence and increases the risk of developing cancer, by promoting the formation of chromosome aberrations and deregulating the expression of oncogenes. Here, the main recent evidence regarding the impact of some B vitamins on DNA damage and cancer is summarized, providing an integrated and updated analysis, mainly centred on vitamin B
6
. In many cases, it is difficult to finely predict the optimal vitamin rate that is able to protect against DNA damage, as this can be influenced by a given individual's genotype. For this purpose, a precious resort is represented by model organisms which allow limitations imposed by more complex systems to be overcome. In this review, we show that
Drosophila
can be a useful model to deeply understand mechanisms underlying the relationship between vitamin B
6
and genome integrity.
Auditory cortical representation of music favours the perceived beat
Authors: Rajendran Vani G. , Harper Nicol S. , Schnupp Jan W. H.
Published: March 2020

Previous research has shown that musical beat perception is a surprisingly complex phenomenon involving widespread neural coordination across higher-order sensory, motor and cognitive areas. However, the question of how low-level auditory processing must necessarily shape these dynamics, and therefore perception, is not well understood. Here, we present evidence that the auditory cortical representation of music, even in the absence of motor or top-down activations, already favours the beat that will be perceived. Extracellular firing rates in the rat auditory cortex were recorded in response to 20 musical excerpts diverse in tempo and genre, for which musical beat perception had been characterized by the tapping behaviour of 40 human listeners. We found that firing rates in the rat auditory cortex were on average higher on the beat than off the beat. This ‘neural emphasis’ distinguished the beat that was perceived from other possible interpretations of the beat, was predictive of the degree of tapping consensus across human listeners, and was accounted for by a spectrotemporal receptive field model. These findings strongly suggest that the ‘bottom-up’ processing of music performed by the auditory system predisposes the timing and clarity of the perceived musical beat.
The interaction between map complexity and crowd movement on navigation decisions in virtual reality
Authors: Zhao Hantao , Thrash Tyler , Grossrieder Armin , Kapadia Mubbasir , Moussaïd Mehdi , Hölscher Christoph , Schinazi Victor R.
Published: March 2020

A carefully designed map can reduce pedestrians’ cognitive load during wayfinding and may be an especially useful navigation aid in crowded public environments. In the present paper, we report three studies that investigated the effects of map complexity and crowd movement on wayfinding time, accuracy and hesitation using both online and laboratory-based networked virtual reality (VR) platforms. In the online study, we found that simple map designs led to shorter decision times and higher accuracy compared to complex map designs. In the networked VR set-up, we found that co-present participants made very few errors. In the final VR study, we replayed the traces of participants’ avatars from the second study so that they indicated a different direction than the maps. In this scenario, we found an interaction between map design and crowd movement in terms of decision time and the distributions of locations at which participants hesitated. Together, these findings can help the designers of maps for public spaces account for the movements of real crowds.
Divergent strategies in faeces avoidance between two cercopithecoid primates
Authors: Sarabian Cécile , Ngoubangoye Barthélémy , MacIntosh Andrew J. J.
Published: March 2020

Parasites constitute a major selective pressure which has shaped animal behaviour through evolutionary time. One adaption to parasites consists of recognizing and avoiding substrates or cues that indicate their presence. Among substrates harbouring infectious agents, faeces are known to elicit avoidance behaviour in numerous animal species. However, the function and mechanisms of faeces avoidance in non-human primates has been largely overlooked by scientists. In this study, we used an experimental approach to investigate whether aversion to faeces in a foraging context is mediated by visual and olfactory cues in two cercopithecoid primates: mandrills (Mandrillus sphinx) and long-tailed macaques (Macaca fascicularis). Visual and olfactory cues of faeces elicited lower food consumption rates in mandrills and higher food manipulation rates in long-tailed macaques. Both results support the infection-avoidance hypothesis and confirm similar tendencies observed in other primate species. More studies are now needed to investigate the divergence of avoidance strategies observed in non-human primates regarding food contamination.
Ethylenediamine loading into a manganese-based metal–organic framework enhances water stability and carbon dioxide uptake of the framework
Authors: Asghar Aisha , Iqbal Naseem , Aftab Leena , Noor Tayyaba , Kariuki Benson M. , Kidwell Luke , Easun Timothy L.
Published: March 2020

Metal–organic frameworks (MOFs) based on 2,5-dihydroxyterepthalic acid (DOBDC) as the linker show very high CO
2
uptake capacities at low to moderate CO
2
pressures; however, these MOFs often require expensive solvent for synthesis and are difficult to regenerate. We have synthesized a Mn-DOBDC MOF and modified it to introduce amine groups into the structure by functionalizing its metal coordination sites with ethylenediamine (EDA). Repeat framework synthesis was then also successfully performed using recycled dimethylformamide (DMF) solvent. Characterization by elemental analysis, FTIR and thermogravimetric studies suggest that EDA molecules are successfully substituting the original metal-bound DMF. This modification not only enhances the material's carbon dioxide sorption capacity, increasing stability to repeated CO
2
sorption cycles, but also improves the framework's stability to moisture. Moreover, this is one of the first amine-modified MOFs that can demonstrably be synthesized using recycled solvent, potentially reducing the future costs of production at larger scales.
Comparative toxicity of larvicides and growth inhibitors on
Aedes aegypti
from select areas in Jamaica
Authors: Francis Sheena , Crawford Jervis , McKenzie Sashell , Campbell Towanna , Wright Danisha , Hamilton Trevann , Huntley-Jones Sherine , Spence Simone , Belemvire Allison , Alavi Kristen , Gutierrez Carolina Torres
Published: March 2020

Insecticide resistance has become problematic in tropical and subtropical regions, where
Aedes
mosquitoes and
Aedes
-borne arboviral diseases thrive. With the recent occurrence of chikungunya and the Zika virus in Jamaica, the Ministry of Health and Wellness, Jamaica, partnered with the United States Agency for International Development to implement multiple intervention activities to reduce the
Aedes aegypti
populations in seven parishes across the island and to assess the susceptibility of collected samples to various concentrations of temephos,
Bacillus thuringiensis
subsp.
israelensis,
(Bti), diflubenzuron and methoprene. Of the insecticides tested, only temephos has been used in routine larviciding activities in the island. The results showed that only temephos at concentrations 0.625 ppm and Bti at concentrations 6–8 ppm were effective at causing 98–100% mortality of local
Ae. aegypti
at 24 h exposure. Surprisingly, the growth inhibitors diflubenzuron and methoprene had minimal effect at preventing adult emergence in
Ae. aegypti
larvae in the populations tested. The results demonstrate the need for insecticide resistance testing as a routine part of vector control monitoring activies in order to determine useful tools that may be incorporated to reduce the abundance of
Ae. aegypti
.
Colobops
: a juvenile rhynchocephalian reptile (Lepidosauromorpha), not a diminutive archosauromorph with an unusually strong bite
Authors: Scheyer Torsten M. , Spiekman Stephan N. F. , Sues Hans-Dieter , Ezcurra Martín D. , Butler Richard J. , Jones Marc E. H.
Published: March 2020

Correctly identifying taxa at the root of major clades or the oldest clade-representatives is critical for meaningful interpretations of evolution. A small, partially crushed skull from the Late Triassic (Norian) of Connecticut, USA, originally described as an indeterminate rhynchocephalian saurian, was recently named
Colobops noviportensis
and reinterpreted as sister to all remaining Rhynchosauria, one of the earliest and globally distributed groups of herbivorous reptiles. It was also interpreted as having an exceptionally reinforced snout and powerful bite based on an especially large supratemporal fenestra. Here, after a re-analysis of the original scan data, we show that the skull was strongly dorsoventrally compressed post-mortem, with most bones out of life position. The cranial anatomy is consistent with that of other rhynchocephalian lepidosauromorphs, not rhynchosaurs. The ‘reinforced snout' region and the ‘exceptionally enlarged temporal region’ are preservational artefacts and not exceptional among clevosaurid rhynchocephalians.
Colobops
is thus not a key taxon for understanding diapsid feeding apparatus evolution.
How to build a new athletic track to break records
Authors: Aftalion Amandine , Trélat Emmanuel
Published: March 2020

We introduce a new optimal control model which encompasses pace optimization and motor control effort for a runner on a fixed distance. The system couples mechanics, energetics, neural drive to an economic decision theory of cost and benefit. We find how effort is minimized to produce the best running strategy, in particular, in the bend. This allows us to discriminate between different types of tracks and estimate the discrepancy between lanes. Relating this model to the optimal path problem called the Dubins path, we are able to determine the geometry of the optimal track and estimate record times.
Inner surface of
Nepenthes
slippery zone: ratchet effect of lunate cells causes anisotropic superhydrophobicity
Authors: Wang Lixin , Zhang Shuoyan , Li Shanshan , Yan Shixing , Dong Shiyun
Published: March 2020

Inner surface of
Nepenthes
slippery zone shows anisotropic superhydrophobic wettability. Here, we investigate what factors cause the anisotropy via sliding angle measurement, morphology/structure observation and model analysis. Static contact angle of ultrapure-water droplet exhibits the value of 154.80°–156.83°, and sliding angle towards pitcher bottom and up is 2.82 ± 0.45° and 5.22 ± 0.28°, respectively. The slippery zone under investigation is covered by plenty of lunate cells with both ends bending downward, and a dense layer of wax coverings without directional difference in morphology/structure. Results indicate that the slippery zone has a considerable anisotropy in superhydrophobic wettability that is most likely caused by the lunate cells. A model was proposed to quantitatively analyse how the structure characteristics of lunate cells affect the anisotropic superhydrophobicity, and found that the slope/precipice structure of lunate cells forms a ratchet effect to cause ultrapure-water droplet to roll towards pitcher bottom/up in different order of difficulty. Our investigation firstly reveals the mechanism of anisotropic superhydrophobic wettability of
Nepenthes
slippery zone, and inspires the bionic design of superhydrophobic surfaces with anisotropic properties.
Nearest vent, dearest friend: biodiversity of Tiancheng vent field reveals cross-ridge similarities in the Indian Ocean
Authors: Sun Jin , Zhou Yadong , Chen Chong , Kwan Yick Hang , Sun Yanan , Wang Xuyang , Yang Lei , Zhang Ruiyan , Wei Tong , Yang Yi , Qu Lingyun , Sun Chengjun , Qian Pei-Yuan
Published: March 2020

Biodiversity of hydrothermal vents in the Indian Ocean, particularly those on the Southwest Indian Ridge (SWIR), are still relatively poorly understood. The Tiancheng field on the SWIR was initially reported with only a low-temperature diffuse flow venting area, but here we report two new active areas, including a chimney emitting high-temperature vent fluids. Biological sampling in these new sites doubled the known megafauna and macrofauna richness reported from Tiancheng. Significantly, we found several iconic species, such as the scaly-foot snail and the firstAlviniconchapopulation on the SWIR. Tiancheng shares a high proportion of taxa with vents on the Central Indian Ridge (CIR) and lacks a number of key taxa that characterize other vents investigated so far on the SWIR. Population genetics of the scaly-foot snail confirmed this, as the Tiancheng population was clustered with populations from the CIR, showing low connectivity with the Longqi field. Unlike the previously examined populations, scales of the Tiancheng scaly-foot snail were coated in zinc sulfide, although this results only from precipitation. The close connection between Tiancheng and CIR vents indicates that the dispersal barrier for vent endemic species is not the Rodriguez Triple Junction as previously suggested but the transformation faults between Tiancheng and Longqi, warranting further studies on deep currents in this area to resolve the key barrier, which has important implications for biological conservation.
Two-loop
n
-point anomalous amplitudes in N=4 supergravity
Authors: Bern Zvi , Kosower David , Parra-Martinez Julio
Published: March 2020

We compute the anomalous two-loop four-point amplitudes in

N

=
4

pure supergravity, using unitarity and the double-copy construction. We also present all terms determined by four-dimensional cuts in two all-multiplicity two-loop anomalous superamplitudes. This result provides the first two-loop
n
-point gravity amplitude, up to a class of undetermined terms, which we determine completely at four points. We show that a recently proposed finite counterterm cancels these amplitudes to this order. We argue that the counterterm does not spoil the three-loop finiteness of anomalous amplitudes in the

N

=
4

theory.
Transmission and reflection at the boundary of a random two-component composite
Authors: Willis J. R.
Published: March 2020

A half-space
x
2
 > 0 is occupied by a two-component statistically uniform random composite with specified volume fractions and two-point correlation. It is bonded to a uniform half-space
x
2
 < 0 from which a plane wave is incident. The transmitted and reflected mean waves are calculated via a variational formulation that makes optimal use of the given statistical information. The problem requires the specification of the properties of three media: those of the two constituents of the composite and those of the homogeneous half-space. The complexity of the problem is minimized by considering a model acoustic-wave problem in which the three media have the same modulus but different densities. It is formulated as a problem of Wiener–Hopf type which is solved explicitly in the particular case of an exponentially decaying correlation function. Possible generalizations are discussed in a brief concluding section.
Thefruitlessgene affects female receptivity and species isolation
Authors: Chowdhury Tabashir , Calhoun Ryan M. , Bruch Katrina , Moehring Amanda J.
Published: March 2020

Female mate rejection acts as a major selective force within species, and can serve as a reproductive barrier between species. In spite of its critical role in fitness and reproduction, surprisingly little is known about the genetic or neural basis of variation in female mate choice. Here, we identifyfruitlessas a gene affecting female receptivity withinDrosophila melanogaster, as well as femaleDrosophila simulansrejection of maleD. melanogaster. Of the multiple transcripts this gene produces, by far the most widely studied is the sex-specifically spliced transcript involved in the sex determination pathway. However, we find that female rejection behaviour is affected by a non-sex-specifically splicedfruitlesstranscript. This is the first implication offruitlessin female behaviour, and the first behavioural role identified for afruitlessnon-sex-specifically spliced transcript. We found that this locus does not influence preferences via a single sensory modality, examining courtship song, antennal pheromone perception, or perception of substrate vibrations, and we conclude thatfruitlessinfluences mate choice via the integration of multiple signals or through another sensory modality.
Photorhabdus: a tale of contrasting interactions
Authors: Clarke David J
Published: March 2020

Different model systems have, over the years, contributed to our current understanding of the molecular mechanisms underpinning the various types of interaction between bacteria and their animal hosts. The genus

Photorhabdus

comprises Gram-negative insect pathogenic bacteria that are normally found as symbionts that colonize the gut of the infective juvenile stage of soil-dwelling nematodes from the family Heterorhabditis. The nematodes infect susceptible insects and release the bacteria into the insect haemolymph where the bacteria grow, resulting in the death of the insect. At this stage the nematodes feed on the bacterial biomass and, following several rounds of reproduction, the nematodes develop into infective juveniles that leave the insect cadaver in search of new hosts. Therefore

Photorhabdus

has three distinct and obligate roles to play during this life-cycle: (1)

Photorhabdus

must kill the insect host; (2)

Photorhabdus

must be capable of supporting nematode growth and development; and (3)

Photorhabdus

must be able to colonize the gut of the next generation of infective juveniles before they leave the insect cadaver. In this review I will discuss how genetic analysis has identified key genes involved in mediating, and regulating, the interaction between

Photorhabdus

and each of its invertebrate hosts. These studies have resulted in the characterization of several new families of toxins and a novel inter-kingdom signalling molecule and have also uncovered an important role for phase variation in the regulation of these different roles.