bluuebunny/crossref_metadata_2025 huggingface dataset:
Commercial equine production in New Zealand. 2. Growth and development of the equine athlete
Authors: Rogers Chris W. , Gee Erica K. , Bolwell Charlotte F. , Rosanowski Sarah M.
Published: August 2017

During the past 20 years, there has been a contraction in the New Zealand Thoroughbred industry and, to a lesser extent, within the Standardbred industry. These changes have seen an increasing proportion of the market being associated with fewer larger commercial farms. Many of these farms manage their own mares, and the mares and foals of several clients. This, in turn, has increased the similarity of the management of breeding and young stock within New Zealand. The temperate climate allows the majority of the management of breeding and young stock to be pasture based. The predominant pasture is ryegrass–clover mix that has been demonstrated to provide adequate nutrition for growth and development. The temperate climate also permits management of horses at pasture year round, which is proposed to stimulate development of the musculoskeletal system. Apart from a brief period during weaning, most young stock remain at pasture from birth until the start of yearling preparation. Free access to pasture exercise provides the opportunity to stimulate the musculoskeletal system for the future challenges as a racehorse. The export focus of many of the equine industries heavily influences the management decisions. Despite the availability of good-quality pasture post-weaning, many foals receive up to 50% of the daily dietary energy requirement as concentrates, possibly reflecting the emphasis on early sales as yearlings and the drive to optimise growth. The observations of drench resistance of common internal parasites presents an emerging problem for pasture-based production systems. A large proportion of the Thoroughbred foal crop is exported as yearlings or ready to run 2-year-olds. There is an increasing trend for Standardbreds to be sold as yearlings and this has resulted in changes in the management of Standardbred young stock.
Evidence for frequency-dependent cortical plasticity in the human brain
Authors: Lea-Carnall Caroline A. , Trujillo-Barreto Nelson J. , Montemurro Marcelo A. , El-Deredy Wael , Parkes Laura M.
Published: August 2017

Significance

We extend the concept of frequency-dependent plasticity, thus far used to describe synaptic selective adaptation in response to stimulation at different frequencies, to the level of cortical networks. We demonstrate selective changes in perception, functional topography, and connectivity of the primary somatosensory cortex following tactile stimulation at different frequencies. Simulation of a network of oscillators incorporating Hebbian learning reproduced these changes and confirmed the influence of intrinsic cortical resonance on plasticity. We thus show that frequency-dependent plasticity extends to the cortical level and is influenced by cortical resonance, which is of potential importance for optimization of therapeutic stimulation approaches to augment learning and memory.
Mitogenic stimulation accelerates influenza-induced mortality by increasing susceptibility of alveolar type II cells to infection
Authors: Nikolaidis Nikolaos M. , Noel John G. , Pitstick Lori B. , Gardner Jason C. , Uehara Yasuaki , Wu Huixing , Saito Atsushi , Lewnard Kara E. , Liu Huan , White Mitchell R. , Hartshorn Kevan L. , McCormack Francis X.
Published: August 2017

Significance

Influenza is a recurring global health threat that preferentially targets vulnerable groups such as the very young, the pregnant, the elderly, and the infirm. The spread of influenza A virus (IAV) from the epithelium of the conducting airway to the alveolar epithelium is a pivotal event in the pathogenesis of primary viral pneumonia. Host susceptibility to IAV pneumonia is often attributed to altered immunity, and cell autonomous vulnerability states of the alveolar epithelium, such as proliferative tone, are rarely considered. Here we demonstrate that mitogenic stimulation of alveolar epithelial type II cells renders them susceptible to IAV infection in an mTOR-dependent manner.
Microfluidic perfusion shows intersarcomere dynamics within single skeletal muscle myofibrils
Authors: de Souza Leite Felipe , Minozzo Fabio C. , Altman David , Rassier Dilson E.
Published: August 2017

Significance

The sarcomere contains a variety of molecules responsible for force generation in striated muscles. During muscle contraction, many sarcomeres work cooperatively to produce force. The mechanisms behind the interaction among sarcomeres during muscle activation have puzzled scientists for decades. To investigate intersarcomere dynamics, we used microfluidic perfusions to activate a single sarcomere within isolated myofibrils. Using computational sarcomere tracking, we observed that the contraction of one sarcomere affects other sarcomeres in series. Studying the interactions between sarcomeres is crucial, because sarcomere nonuniformity has been long associated with several phenomena in muscle contraction that cannot be easily understood.
Synthetic quorum sensing in model microcapsule colonies
Authors: Shum Henry , Balazs Anna C.
Published: August 2017

Significance

Many organisms, from bacteria to humans, can sense their local population density and modify their behavior in crowded environments. This density-dependent behavior, known as quorum sensing, is a highly desirable attribute for synthetic systems because it permits novel self-recognition and self-regulating functionality. Using theory and simulation, we design chemical-producing microcapsules that display quorum sensing. When the chemical production is regulated by a biomimetic feedback loop, the capsules exhibit tunable transitions between steady (“off”) and oscillatory (“on”) states as a function of the number and number density of microcapsules in a colony. Such a system can behave as a mechanoresponsive material, modulating chemical activity when applied stresses alter the spatial configuration of the capsules.
Lipid rafts sense and direct electric field-induced migration
Authors: Lin Bo-jian , Tsao Shun-hao , Chen Alex , Hu Shu-Kai , Chao Ling , Chao Pen-hsiu Grace
Published: August 2017

Significance

Electric fields control embryonic development and wound healing through directing and enhancing cell migration and proliferation. However, details pertaining to electric sensing of cells remain unclear. Many studies have reported involvement of different cell surface proteins, yet the identity of the electric field sensor is unknown. We demonstrate that the detergent-resistant membrane nanodomains, known as lipid rafts, act as the primary sensor to electric field-induced directional cell migration. These nanodomains respond to electric fields as mobile complexes that polarize, coalesce, and partition membrane proteins and in turn activate intracellular signaling events to orient cell migration.
Structural basis of a histidine-DNA nicking/joining mechanism for gene transfer and promiscuous spread of antibiotic resistance
Authors: Pluta Radoslaw , Boer D. Roeland , Lorenzo-Díaz Fabián , Russi Silvia , Gómez Hansel , Fernández-López Cris , Pérez-Luque Rosa , Orozco Modesto , Espinosa Manuel , Coll Miquel
Published: August 2017

Significance

Nearly 90% of lethal antibiotic-resistant infections in the United States are caused by Gram-positive pathogens, with
Staphylococcus aureus
accounting for more than one-half of these. Antibiotic resistance is often encoded by plasmids and integrative elements that are exchanged between bacteria through conjugative DNA transfer. During conjugation, a relaxase protein binds, nicks, and covalently attaches to the 5′-end of the DNA, guiding it to the recipient cell, where it restores its circular closed form. We show that relaxase MobM from the promiscuous plasmid pMV158 uses a hitherto unseen mechanism for DNA nicking/closing that is based on the formation of a protein-DNA phosphoramidate adduct. Moreover, our analysis reveals that MobM-like histidine relaxases account for 85% of all relaxases in
S. aureus
isolates.
Optimal decision making and matching are tied through diminishing returns
Authors: Kubanek Jan
Published: August 2017

Significance

Decisions critically affect the well-being of individuals and societies. However, how to suitably model, understand, and predict people’s decisions has been a long-standing challenge. Economic models view individuals as optimal decision makers who maximize their overall reward income. Psychologists and ecologists have observed that decision makers tend to use a relatively simpler “matching” strategy, distributing their behavior in proportion to relative worth of their options. This article demonstrates that matching can be an optimal strategy for decision makers when the rewards associated with their options diminish with the invested effort, a relationship known as the law of diminishing returns. Because diminishing returns are prevalent in nature and social settings, the commonly observed matching behavior is not only simple but also efficient and rational.
Neural basis for hand muscle synergies in the primate spinal cord
Authors: Takei Tomohiko , Confais Joachim , Tomatsu Saeka , Oya Tomomichi , Seki Kazuhiko
Published: August 2017

Significance

How the CNS coordinates complex movements, each comprising a large number of muscles and joints, to attain a behavioral goal remains a fundamental question. Previous studies in phylogenetically older animals indicate that functional modules in the spinal cord (“muscle synergies”) construct motor behaviors. However, whether similar mechanisms exist in primates is unknown. For example, hand movements are believed to depend on direct inputs from the corticomotoneuronal pathway, which bypass spinal interneuron circuits. Here we demonstrate that spinal premotor interneurons underlie the spatiotemporal patterns of muscle synergies in primates during a precision grip task. Our results suggest that the phylogenetically older premotor interneuron system provides synergistic control of hand movements upon which the newer corticomotoneuronal system superimposes more fractionated control.
Protein nanocages that penetrate airway mucus and tumor tissue
Authors: Huang Xinglu , Chisholm Jane , Zhuang Jie , Xiao Yanyu , Duncan Gregg , Chen Xiaoyuan , Suk Jung Soo , Hanes Justin
Published: August 2017

Significance

In designing new nanoparticle drug delivery systems, it is critical to identify simple formulations that overcome multiple biological barriers while being safe, reproducible, and scalable. We modified human ferritin nanocages using a unique PEGylation strategy, which provides a highly uniform, stable, and compact nanocarrier platform capable of overcoming multiple biological barriers, specifically penetration of airway mucus and tumor tissue, selective uptake by cancer cells, and drug release triggered only upon cell uptake. Surprisingly, PEGylation of ferritin to overcome the mucus barrier did not interfere with the ability of the nanocages to form particles, penetrate tumor tissues, and enter cells. Proof-of-concept of the system is provided in the treatment of an aggressive orthotopic model of lung cancer.
Revised M06-L functional for improved accuracy on chemical reaction barrier heights, noncovalent interactions, and solid-state physics
Authors: Wang Ying , Jin Xinsheng , Yu Haoyu S. , Truhlar Donald G. , He Xiao
Published: August 2017

Significance

Local exchange−correlation functionals, which depend on the local spin densities, their gradients, and the local spin-specific kinetic energy densities, have been widely used for electronic structure calculations in both chemistry and physics, owing to their computational efficiency in plane wave codes and for large molecules and to their relatively high accuracy for transition metals and other inherently multiconfigurational systems. Minnesota 2006 local functional (M06-L) has proven to be one of the most accurate local functionals currently available, but it has room for improvement with regard to numerical stability and overall accuracy. Here we present a revised M06-L functional, named revM06-L, which gives both smoother potential energy curves and improved overall accuracy, especially for chemical reaction barrier heights, noncovalent interactions, and solid-state physics.
Therapeutically targeting glypican-2 via single-domain antibody-based chimeric antigen receptors and immunotoxins in neuroblastoma
Authors: Li Nan , Fu Haiying , Hewitt Stephen M. , Dimitrov Dimiter S. , Ho Mitchell
Published: August 2017

Significance

Neuroblastoma is a childhood cancer that remains an important clinical challenge. It is fatal in almost half of the patients despite advances in multimodal treatments. In this report, we show that the cell surface glycoprotein glypican-2 (GPC2) is overexpressed in neuroblastomas when compared with normal tissues and that a high expression level is correlated with poor survival of neuroblastoma. We also describe that GPC2 has proliferative effects in neuroblastoma via activating Wnt signaling and its downstream target genes including N-Myc, a major driver for neuroblastoma tumorigenesis. We have produced the immunotoxins and chimeric antigen receptor T cells that target GPC2 and exhibit promising antitumor activities in cell and mouse models. This study suggests GPC2 as a promising target in neuroblastoma.
Interactions between feedback and lateral connections in the primary visual cortex
Authors: Liang Hualou , Gong Xiajing , Chen Minggui , Yan Yin , Li Wu , Gilbert Charles D.
Published: August 2017

Significance

One of the fundamental tasks of vision is to group the image elements that belong to one object and to segregate them from other objects and the background. Such a process, known as contour integration, is thought of as involving both long-range horizontal connections in the primary visual cortex (V1) and feedback influences from higher cortical areas such as V4. Using conditional Granger causality analysis of simultaneously recorded neurons in monkey visual cortical areas V1 and V4, we are able to dissect the respective contributions of intraareal and interareal interactions during contour integration, indicating that feedback and lateral connections work synergistically to group and segment visual image components.
Te-raising is clitic climbing
Authors: Pots Cora
Published: August 2017

In contrast to finite verb clusters, non-finite verb clusters have thus far received little attention in the literature. In this paper, I present new data from a large-scale questionnaire study on variation in non-finite three-verb clusters in Dutch, investigating the position and presence of the infinitival marker te ‘to’. The results reveal that a group of Dutch speakers allows te to occur in a higher position than it should based on selection requirements. I propose that for these speakers te has the morphosyntactic status of a clitic, whereas for all other speakers te is a verbal prefix. I analyse Dutch verb clusters as cases of functional restructuring and te-raising as an instance of clitic climbing, a well-known phenomenon from other languages with restructuring, such as Italian.
Learning to suspend implicated contrast
Authors: Wolterbeek Joris , Dijke Lisa van , Hogeweg Lotte , Meyer Caitlin
Published: August 2017

Children acquire the meaning of ook ‘also’ in Dutch relatively late (Bergsma 2006), although this focus particle is highly frequent. We argue that this late acquisition is caused by a pragmatic rule: contrastive implicature. We follow Sæbø (2004), who argues that additives are used because without them, the sentences they appear in would be interpreted as contrastive in relation to the context. Data from a sentence completion task administered to Dutch L1 learners (N = 62, ages 4;0–5;11) show that, on average, four-year-olds do not distinguish sentences with ook from sentences without ook. Five-year-olds do better on sentences with ook but worse on sentences without it. We argue that they have generally acquired contrastive implicature: they apply the correct contrastive interpretation to sentences without ook, but overgeneralize this implicature to sentences with ook, before completely acquiring the meaning of ook.
The role of context in the formation ofhejab‘veiling’ metaphors inhejabbillboards and posters in Iran
Authors: Bakhtiar Mohsen
Published: August 2017

Properhejabobservance has long been an important issue to political-religious conservatives in Iran who, in recent years, have relied on metaphorical language to persuade Iranian women to dress modestly in public. The present paper, based onKövecses’s (2015)account of metaphor in context, explores the role of contextual factors involved in the formation ofhejablinguistic metaphors used in 56 pro-hejabbillboards and posters. Data analysis indicates that the moral and social status of women are depicted as being determined by, or correlated with, their degree of veiling. On that basis, properly covered up women are shown to be the recipients of very positive metaphorical conceptualizations (aspearls,flowers, andangels), whereas immodestly dressed women are negatively pictured as being subject to sexual objectification (asunwrapped edibles). Moreover, thehejab is a protective coveris shown to be the metaphor instantiated in many of the billboards and posters. The protective function ofhejabis highlighted by conceptualizing corrupt men asfliesanddevils.Finally, the metaphorical patterns represent the contextual role of political and religious ideology, key cultural concepts, and show entrenched conventional conceptual metaphors and metonymies in the production of novel metaphors.
Sports metaphors and women’s empowerment in the 2014 European election campaign in Romania
Authors: Dumitriu Diana-Luiza , Negrea-Busuioc Elena
Published: August 2017

This paper examines sports metaphors as symbolic resources for electoral discourse, focusing on both their conventional nature and their strategic value in delivering the political message. It takes the form of a case study analyzing the multimodal realizations of the ‘EuroChampion’ sports metaphor in five posters used by the Romanian Liberal Party in the 2014 campaign for the European Parliament. We argue that the ‘EuroChampion’ metaphor and the richness of sports imagery are strategically used to enhance deeper doctrinal party positioning, such as promoting meritocracy and competitiveness, while, at the same time, empowering women candidates in the election.
N
1, N14-diferuloylspermine as an antioxidative phytochemical contained in leaves of Cardamine fauriei
Authors: Abe Keima , Matsuura Hideyuki , Ukai Mitsuko , Shimura Hanako , Koshino Hiroyuki , Suzuki Takashi
Published: August 2017

Most Brassicaceae vegetables are ideal dietary sources of antioxidants beneficial for human health. Cardamine fauriei (Ezo-wasabi in Japanese) is a wild, edible Brassicaceae herb native to Hokkaido, Japan. To clarify the main antioxidative phytochemical, an 80% methanol extraction from the leaves was fractionated with Diaion® HP-20, Sephadex® LH-20, and Sep-Pak® C18 cartridges, and the fraction with strong antioxidant activity depending on DPPH method was purified by HPLC. Based on the analyses using HRESIMS and MS/MS, the compound might be N1, N14-diferuloylspermine. This rare phenol compound was chemically synthesized, whose data on HPLC, MS and 1H NMR were compared with those of naturally derived compound from C. fauriei. All results indicated they were the same compound. The radical-scavenging properties of diferuloylspermine were evaluated by ORAC and ESR spin trapping methods, with the diferuloylspermine showing high scavenging activities of the ROO·, O2·−, and HO· radicals as was those of conventional antioxidants.
Cue competition influences biconditional discrimination
Authors: Byrom Nicola C , Murphy Robin A
Published: August 2017

When multiple cues are presented in compound and trained to predict an outcome, the cues may compete for association with an outcome. However, if both cues are necessary for solution of the discrimination, then competition might be expected to interfere with the solution of the discrimination. We consider how unequal stimulus salience influences learning in configural discriminations, where no individual stimulus predicts the outcome. We compared two hypotheses: (1) salience modulation minimises the initial imbalance in salience and (2) unequal stimulus salience will impair acquisition of configural discriminations. We assessed the effect of varying stimulus salience in a biconditional discrimination (AX+, AY−, BX−, BY+). Across two experiments, we found stronger discrimination when stimuli had matched, rather than mismatched, salience, supporting our second hypothesis. We discuss the implications of this finding for Mackintosh’s model of selective attention, modified elemental models and configural models of learning.
Nondivergence parabolic equations in weighted variable exponent spaces
Authors: Byun Sun-Sig , Lee Mikyoung , Ok Jihoon
Published: August 2017

We prove the global Calderón-Zygmund estimates for second order parabolic equations in nondivergence form in weighted variable exponent Lebesgue spaces. We assume that the associated variable exponent is log-Hölder continuous, the weight is of a certain Muckenhoupt class with respect to the variable exponent, the coefficients of the equation are the functions of small bonded mean oscillation, and the underlying domain is a

C

1
,
1

C^{1,1}

-domain.
Targeting Accuracy of the Subthalamic Nucleus in Deep Brain Stimulation Surgery: Comparison Between 3 T T2-Weighted Magnetic Resonance Imaging and Microelectrode Recording Results
Authors: Nowacki Andreas , Debove Ines , Fiechter Michael , Rossi Frédéric , Oertel Markus Florian , Wiest Roland , Schüpbach Michael , Pollo Claudio
Published: August 2017

BACKGROUND

Targeting accuracy in deep brain stimulation (DBS) surgery can be defined as the level of accordance between selected and anatomic real target reflected by characteristic electrophysiological results of microelectrode recording (MER).

OBJECTIVE

To determine the correspondence between the preoperative predicted target based on modern 3-T magnetic resonance imaging (MRI) and intraoperative MER results separately on the initial and consecutive second side of surgery.

METHODS

Retrospective cohort study of 86 trajectories of DBS electrodes implanted into the subthalamic nucleus (STN) of patients with Parkinson's disease. The entrance point of the electrode into the STN and the length of the electrode trajectory crossing the STN were determined by intraoperative MER findings and 3 T T2-weighted magnetic resonance images with 1-mm slice thickness.

RESULTS

Average difference between MRI- and MER-based trajectory lengths crossing the STN was 0.28 ± 1.02 mm (95% CI: −0.51 to −0.05 mm). There was a statistically significant difference between the MRI- and MER-based entry points on the initial and second side of surgery (P = .04). Forty-three percent of the patients had a difference of more than ±1 mm of the MRI-based-predicted and the MER-based-determined entry points into the STN with values ranging from −3.0 to + 4.5 mm.

CONCLUSION

STN MRI-based targeting is accurate in the majority of cases on the first and second side of surgery. In 43% of implanted electrodes, we found a relevant deviation of more than 1 mm, supporting the concept of MER as an important tool to guide and optimize targeting and electrode placement.
Analysis of Intraoperative Cone-Beam Computed Tomography Combined With Image Guidance for Lateral Lumbar Interbody Fusion
Authors: Liu Xilin , Joseph Jacob R , Smith Brandon W , Saadeh Yamaan , Park Paul
Published: August 2017

BACKGROUND

Minimally invasive lateral lumbar interbody fusion (LLIF) is traditionally performed with biplanar fluoroscopy. Recent literature demonstrates that intraoperative cone-beam computed tomography combined with spinal navigation can be safely utilized for localization and cage placement in LLIF.

OBJECTIVE

To evaluate the accuracy and safety of cage placement using spinal navigation in LLIF, as well as to evaluate the radiation exposure to surgeon and staff during the procedure.

METHODS

The authors performed a retrospective analysis of a prospectively acquired database of patients undergoing LLIF with image-based navigation performed from April 2014 to July 2016 at a single institution. The medical records were reviewed, and data on clinical outcomes, cage accuracy, complications, and radiation exposure were recorded. All patients underwent a minimum 30-d clinical follow-up to assess intraoperative and short-term complications associated with their LLIF.

RESULTS

Sixty-three patients comprising 117 spinal levels were included in the study. There were 36 (57.1%) female and 27 (42.9%) male patients. Mean age was 62.7 yr (range 24-79 yr). A mean 1.9 (range 1-4) levels per patient were treated. Cages were placed in the anterior or middle of 115 (98.3%) disc spaces. Image-guided cage trajectory was accurate in 116/117 levels (99.1%). In a subgroup analysis of 18 patients, mean fluoroscopy time was 11.7 ± 9.7 s per level. Sixteen (25.4%) patients experienced a complication related to approach.

CONCLUSION

Use of intraoperative cone-beam computed tomography combined with spinal navigation for LLIF results in accurate and safe cage placement as well as significantly decreased surgeon and staff radiation exposure.
Do Exercise Interventions Improve Participation in Life Roles in Older Adults? A Systematic Review and Meta-Analysis
Authors: Beauchamp Marla K. , Lee Annemarie , Ward Rachel F. , Harrison Samantha M. , Bain Paul A. , Goldstein Roger S. , Brooks Dina , Bean Jonathan F , Jette Alan M
Published: August 2017

Background

The World Health Organization recognizes participation in meaningful life roles as a key component of health. However, the evidence base for interventions to improve participation remains inconclusive. In particular, whether exercise interventions improve participation in life roles is unclear.

Purpose

The aim of this review was to evaluate the effect of physical exercise interventions on participation in life roles in older adults residing in the community.

Data sources

The PubMed, Embase, CINAHL, Cochrane, and PEDro databases were searched from inception through March 2015.

Study selection

Randomized controlled trials comparing the effects of an exercise intervention to usual care on participation in life roles in adults who were 60 years of age or older were included in this review.

Data extraction

Teams of 2 investigators independently extracted data on participation. Methodological quality was appraised using the Cochrane tool for assessing the risk of bias. The protocol was registered with Prospero (CRD42014014880).

Data synthesis

Eighteen randomized controlled trials with a total of 2,315 participants met the inclusion criteria. Standardized mean differences (SMDs) with 95% CIs were calculated using a random-effects model. A meta-analysis of 16 studies showed no overall effect of the exercise interventions on participation (SMD = 0.03; 95% CI = −0.10 to 0.16). Subgroup analysis showed that exercise interventions lasting 12 months or more had a small positive effect on participation (SMD = 0.15; 95% CI = 0.02 to 0.28).

Limitations

Limitations included variability in definitions and measures of participation.

Conclusions

In general, exercise interventions do not improve participation in life roles in older adults. The results do not support the implicit assumption that exercise-based interventions associated with improved function/activity also result in improved participation. Investigation of complex interventions that go beyond exercise to address participation in life roles for older adults is warranted.
A Calming Cushion as a Therapeutic Wellness Tool for Youths with Disabilities and History of Trauma
Authors: Polak Reizel , Hutchinson Dori , Perryman Louise , Brueck Stephanie
Published: August 2017

Seclusion and restraint are commonly used by residential staff to control unsafe behaviors of youths with disabilities and complex trauma histories. This pilot study examined the effect of a nonrestraining cushion as a calming device and wellness tool in a setting that prohibits supportive physical contact, to see to what extent the cushion might help these youths to better regulate their emotional distress and unwanted behaviors. Volunteers used the cushion for 15 minutes over 24 sessions. Nine students completed the study and reported reduction in anxiety and agitation, and a soothing feeling with residual effects to their daily routines. This pilot study suggests that the use of a nonrestraining, deep-pressure cushion may simulate a secure holding effect for young people with emotional dysregulation. The cushion is a safe and healing wellness tool that empowers youths and provides programs with an alternative to seclusion and restraint.
Situating Remediation: Accommodating Success and Failure in Medical Education Systems
Authors: Ellaway Rachel H. , Chou Calvin L. , Kalet Adina L.
Published: August 2017

There has been a widespread shift to competency-based medical education (CBME) in the United States and Canada. Much of the CBME discourse has focused on the successful learner, with relatively little attention paid to what happens in CBME systems when learners stumble or fail. Emerging issues, such as the well-documented problem of “failure to fail” and concerns about litigious learners, have highlighted a need for well-defined and integrated frameworks to support and guide strategic approaches to the remediation of struggling medical learners.

This Perspective sets out a conceptual review of current practices and an argument for a holistic approach to remediation in the context of their parent medical education systems. The authors propose parameters for integrating remediation into CBME and describe a model based on five zones of practice along with the rules of engagement associated with each zone. The zones are “normal” curriculum, corrective action, remediation, probation, and exclusion.

The authors argue that, by linking and integrating theory and practice in remediation with CBME, a more integrated systems-level response to differing degrees of learner difficulty and failure can be developed. The proposed model demonstrates how educational practice in different zones is based on different rules, roles, responsibilities, and thresholds for moving between zones. A model such as this can help medical educators and medical education leaders take a more integrated approach to learners’ failures as well as their successes by being more explicit about the rules of engagement that apply in different circumstances across the competency continuum.
The Daunting Career of the Physician–Investigator
Authors: McKinney Ross E.
Published: August 2017

For many years, physician–investigators have had a particularly difficult time with their academic careers, so that they have been labeled an endangered species. In this Invited Commentary, the author defines three career paths for physician–investigators—clinical researcher, clinician–scientist, and physician–scientist. Each of these pathways has common and distinct challenges that should be studied and potential improvements that should be evaluated through pilot research projects.

The first challenge that all physician–investigators face is securing funding. Physicians are funded by their clinical activities, which often lures physician–investigators to increase their clinical work, particularly when research funding from the National Institutes of Health is difficult to secure and seemingly arbitrarily granted. The second challenge is an appointments, promotion, and tenure system that is not responsive to the needs of faculty working across clinical care and research, particularly when it comes to evaluating team science. Physician–investigators not working full-time in either discipline then may have trouble being promoted. The third challenge is the increasing burdens of clinical activities, particularly with the advent of electronic medical records.

In this issue, two articles address overcoming the challenges faced by physician–investigators, one from the National Institutes of Health to grow the workforce and the other to offer organizational and individual solutions to support these investigators in faculty roles. These solutions are encouraging, but data about the extent of the challenges and the potential effects of the solutions are needed to make the physician–investigator career path less daunting.
Mediators of Racial/Ethnic Disparities in Mentored K Award Receipt Among U.S. Medical School Graduates
Authors: Andriole Dorothy A. , Yan Yan , Jeffe Donna B.
Published: August 2017

Purpose

Mentored K (K01/K08/K23) career development awards are positively associated with physicians’ success as independent investigators; however, individuals in some racial/ethnic groups are less likely to receive this federal funding. The authors sought to identify variables that explain (mediate) the association between race/ethnicity and mentored K award receipt among U.S. Liaison Committee for Medical Education–accredited medical school graduates who planned research-related careers.

Method

The authors analyzed deidentified data from the Association of American Medical Colleges and the National Institutes of Health Information for Management, Planning, Analysis, and Coordination II grants database for a national cohort of 28,690 graduates from 1997–2004 who planned research-related careers, followed through August 2014. The authors examined 10 potential mediators (4 research activities, 2 academic performance measures, medical school research intensity, degree program, debt, and specialty) of the association between race/ethnicity and mentored K award receipt in models comparing underrepresented minorities in medicine (URM) and non-URM graduates.

Results

Among 27,521 graduates with complete data (95.9% of study-eligible graduates), 1,147 (4.2%) received mentored K awards (79/3,341 [2.4%] URM; 1,068/24,180 [4.4%] non-URM). All variables except debt were significant mediators; together they explained 96.2% (95%, CI 79.1%–100%) of the association between race/ethnicity and mentored K award.

Conclusions

Research-related activities during/after medical school and standardized academic measures largely explained the association between race/ethnicity and mentored K award in this national cohort. Interventions targeting these mediators could mitigate racial/ethnic disparities in the federally funded physician–scientist research workforce.
Intrawound Vancomycin Powder Associated With Reduced Surgical Site Infection in Rib-based Distraction Surgery
Authors: Haller Justin M. , Heflin John A. , Hulet David A. , Ding Qian , Presson Angela P. , Smith John T.
Published: August 2017

Background:

Despite clinical reports of improved pulmonary function and reduced spinal deformity with rib-based distraction surgery in early-onset scoliosis (EOS) patients, infection remains a common complication, reported as high as 32% in some studies. The purpose of this study was to evaluate intrawound vancomycin powder in pediatric patients managed with rib-based distraction for EOS.

Methods:

This was a single institution retrospective cohort study of EOS patients treated with rib-based distraction. Patients treated with and without intrawound vancomycin were compared. Patients included were younger than 18 years of age, had undergone placement of a rib-based distraction construct, and had a minimum of 6 months’ follow-up. For patients in the vancomycin group, 500 mg of vancomycin powder was placed before wound closure. Complications including infection and revision surgery were recorded. P-values and 95% confidence intervals (CIs) were reported for both unadjusted and adjusted complication rates for prevancomycin and postvancomycin powder. All P-values were calculated at a significance level of 0.05.

Results:

In total, 118 patients were included, accounting for 1035 procedures in the nonvancomycin control group and 252 procedures in the vancomycin group. Both groups were similar with regard to age at initial implant, sex, diagnosis, ambulatory status, and bowel/bladder incontinence. There were 55 (5.3%; 95% CI, 4.1-7.6) postoperative infections in the control group and 3 (1.2%; 95% CI, 0.3-3.8) in the vancomycin group (P=0.008, unadjusted). After adjusting for surgery type and transfusions, the vancomycin group still had a significantly lower infection rate (1.4%; 95% CI, 0.3-3.7 vs. 5.5%; 95% CI, 3.04-6.5; P=0.022). We were unable to demonstrate a difference between the control (3.5%, 95% CI, 2.4-5.1) and vancomycin (1.8%, 95% CI, 0.5-5.7) groups for deep infection (P=0.27).

Conclusions:

Intrawound vancomycin powder significantly reduced the surgical site infection rates following rib-based distraction surgery for EOS. We therefore recommend the use of intrawound vancomycin powder as a standard of care for patients undergoing rib-based distraction surgery.

Level of Evidence:

Pre-post intervention, retrospective cohort study—therapeutic level III.
Electronic Medical Record Use and Satisfaction Among Pediatric Orthopaedic Surgeons
Authors: Copley Lawson A. , Sharps Chester H. , Gerardi Joseph A. , Gupta Sumit K. , Vanderhaave Kelly L. , Lovejoy John F. , Lubicky John P. , Albanese Stephen A. , Jo Chanhee
Published: August 2017

Introduction:

Electronic medical record (EMR) use among pediatric orthopaedic surgeons has evolved substantially within the past decade. In response to the Patient Protection and Affordable Care Act, large hospitals and tertiary pediatric medical centers rapidly acquired and implemented EMRs with uncertainty as to the potential impact on patient care and operational efficiency of subspecialists. This study reviews the background and regulatory framework for Meaningful Use of EMR and assesses the current landscape of EMR utilization by pediatric orthopaedic surgeons.

Methods:

In 2015, the Practice Management Committee distributed a survey regarding EMR use and satisfaction to members of the Pediatric Orthopaedic Society of North America. Survey responses from 324 members were used to analyze levels of satisfaction by EMR platform and practice type and to consider drivers of satisfaction or dissatisfaction of end users.

Results:

Although there were no differences in overall satisfaction based on vendor or practice type, significant differences were noted for 5 specific parameters of satisfaction, including: usefulness of templates, efficiency of practice workflow, information services support, number of logon events, and speed of the system. A user/vendor map is provided to facilitate networking among providers and groups utilizing common EMR platforms to help bring about rational improvements in EMR functionality for the future.

Conclusions:

Substantial effort needs to be made to improve subspecialty-specific EMR documentation, order entry, research tools, and clinical workflows to enhance the processes of care for children with orthopaedic conditions in the era of EMR.

Level of Evidence:

Level IV.
Comparison of Ponte Osteotomies and 3-Column Osteotomies in the Treatment of Congenital Spinal Deformity
Authors: Chan Priscella , Andras Lindsay M. , Nielsen Ena , Sousa Ted , Joiner Elizabeth , Choi Paul D. , Tolo Vernon T. , Skaggs David L.
Published: August 2017

Background:

Congenital spinal deformity (CSD) has traditionally been treated with 3-column osteotomies [hemivertebrectomy (HV) or vertebral column resection (VCR)] to address rigid deformities. Alternatively, multiple Ponte osteotomies (PO) may provide correction while minimizing risk. The purpose of this study was to compare safety and outcomes of patients undergoing surgical treatment for CSD with these 3 procedures.

Methods:

Retrospective review of CSD patients treated with posterior spinal fusion between 1996 to 2013. Patients treated with multiple Ponte osteotomies (PO group) were compared with those managed with 3-column osteotomies (HV/VCR group). Patients with previous instrumentation, isolated cervical deformity, growing spine instrumentation, or <2 year follow-up were excluded. Deformity angular ratio (DAR) was calculated as curve magnitude divided by number of levels of the deformity.

Results:

There were 49 patients [17 PO, 32 HV/VCR (26 HV, 6 VCR)]. For the PO group, mean age was 14 years, and they had an average of 4 ponte osteotomies and 11 levels fused. Mean total DAR was 25 and mean number of congenital anomalies was 1.8 in the PO group. The HV/VCR group had a mean age of 7 years and 5 levels fused. Mean total DAR was 28 and mean number of congenital anomalies was 2.1 in the HV/VCR group. Patients had a mean of 54.1% correction of coronal deformity in the PO group and 54.4% in the HV/VCR group (P=0.78). Signal changes were observed less frequently with PO (1/17) and HV (1/26) than with VCR (4/6), P=0.001. Revision rates were 17.6% (3/17) in the PO group and 37.5% (12/32) in the HV/VCR group (P=0.35).

Conclusions:

Patients with CSD and a mean total DAR of 25 treated with multiple PO and long fusions had correction comparable with the HV/VCR group. Patients treated with VCR had the highest incidence of signal changes and postoperative neurologic deficits.

Level of Evidence:

Level III.
Inaccuracies in ICD Coding for Obesity Would Be Expected to Bias Administrative Database Spine Studies Toward Overestimating the Impact of Obesity on Perioperative Adverse Outcomes
Authors: McLynn Ryan P. , Geddes Benjamin J. , Cui Jonathan J. , Ondeck Nathaniel T. , Bovonratwet Patawut , Shultz Blake N. , Grauer Jonathan N.
Published: August 2017

Study Design.

Retrospective cohort study.

Objective.

To determine if International Classification of Diseases (ICD) coding for obesity is biased toward certain subgroups and how potential bias may influence the outcomes of database research in spine.

Summary of Background Data.

There has been increased use of national databases using administrative data in the spine surgery literature. Past research demonstrates that sensitivity of ICD codes for obesity is poor, but it is unknown if such inaccuracies are systematically biased and if they may bias studies utilizing such data.

Methods.

Patients who underwent elective posterior lumbar fusion, 2013 to 2016, at a large academic hospital were identified. All ICD codes assigned to the encounter were obtained. Body mass index (BMI) was calculated based on height and weight. The sensitivity of ICD coding for obesity was calculated. Sensitivity was compared for subgroups defined by demographic, comorbidity, intraoperative, and postoperative factors. The association of obesity (as defined by BMI≥30 and ICD coding) with 30-day postoperative adverse events was tested with multivariate regression.

Results.

The study included 796 patients. The overall sensitivity of ICD coding for obesity was 42.5%. The sensitivity of ICD coding for obesity was significantly higher in patients with greater BMI, diabetes, American Society of Anesthesiologists class≥III, increased length of stay, venous thromboembolism, any adverse event, and major adverse event. Multivariate analysis for determining outcomes of increased risk with obesity as defined by ICD coding included venous thromboembolism, major adverse events, and any adverse events. However, multivariate analysis for determining outcomes of increased risk with obesity defined by BMI did not yield any positive associations.

Conclusion.

ICD codes for obesity are more commonly assigned to patients with other comorbidities or postoperative complications. Further, use of such nonrandomly assigned ICD codes for obesity has the potential to skew studies to suggest greater associated adverse events than calculated BMI would demonstrate.

Level of Evidence: 3
Muscle-Preserving Selective Laminectomy Maintained the Compensatory Mechanism of Cervical Lordosis After Surgery
Authors: Nori Satoshi , Shiraishi Tateru , Aoyama Ryoma , Ninomiya Ken , Yamane Junichi , Kitamura Kazuya , Ueda Seiji
Published: August 2017

Study Design.

A retrospective single-center study.

Objective.

The aim of this study was to evaluate the compensatory mechanism of cervical lordosis (CL), the changes in cervical sagittal alignment, and range of motion (ROM) after muscle-preserving selective laminectomy (SL).

Summary of Background Data.

CL increases as a compensatory mechanism for the adjustment of cervical sagittal balance or horizontal gaze. However, laminoplasty invades this mechanism and causes kyphosis in higher T1 (C7) slope patients.

Methods.

SL is a posterior surgery selecting the decompression laminae without disturbing the extensor musculature and facet joints. The clinical features and radiological findings of 125 cervical compressive myelopathy patients who underwent C6 single-level SL, C5-C6 two consecutive levels SL, C4-C6 three consecutive levels SL, and C3-C6 four consecutive levels SL were enrolled. Cervical spine lateral radiography was performed before surgery and at the final follow-up. The patients were divided into two groups according to the preoperative C7 slope. Postoperative cervical alignment change was compared between the higher and lower C7 slope groups. Subsequently, pre- and postoperative cervical alignment and cervical ROM were analyzed according to the number of consecutive laminae surgically treated.

Results.

Patients with higher C7 slope had greater lordotic cervical alignment and larger C2-C7 sagittal vertical axis (SVA) pre- and postoperatively. No kyphotic alignment change was observed, even in the higher C7 slope group. C6 SL and C5-C6 SL did not affect C2-C7 angle, and did not increase C2-C7 SVA after surgery. Although C4-C6 SL and C3-C6 SL demonstrated postoperative slight increase in C2-C7 SVA, C2-C7 angle never decreased after surgery. Cervical ROM slightly reduced in the C4-C6 SL and C3-C6 SL groups; however, no reduction of ROM was observed in the C6 SL and C5-C6 SL groups.

Conclusion.

SL preserved the inherent compensatory CL that had been observed preoperatively and maintained cervical sagittal balance after surgery.

Level of Evidence: 4
Methicillin-Resistant Staphylococcus aureus Nasal Swab and Suction Drain Tip Cultures in 4573 Spinal Surgeries
Authors: Kawabata Atsuyuki , Sakai Kenichiro , Sato Hirokazu , Sasaki Shinichi , Torigoe Ichiro , Tomori Masaki , Yuasa Masato , Matsukura Yu , Arai Yoshiyasu
Published: August 2017

Study Design.

A retrospective single-center study.

Objective.

To assess the diagnostic value of methicillin-resistant Staphylococcus aureus (MRSA) nasal swab and suction drain tip cultures.

Summary of Background Data.

The prognostic value of MRSA nasal swab and suction drain tip cultures has not been firmly established in spinal surgery.

Methods.

This study retrospectively included 4573 consecutive patients who underwent spinal surgery between January 2008 and December 2014. Patients diagnosed with infectious disease were excluded. Prophylactic antibiotics were administered intraoperatively and postoperatively for 48 hours. MRSA nasal swab cultures were taken from all patients before surgery. Drains were removed when the volume of postoperative fluid drainage was less than 50 mL in the preceding 24 hours and cultures were made. Surgical site infection (SSI) was defined according to Centers for Disease Control and Prevention criteria.

Results.

SSI was identified in 94 cases (2.1%) and bacteria were isolated in 87 cases (92.6%). Positive MRSA nasal swab cultures were identified in 49 cases (1.1%). There was no significant difference in the SSI positivity rate between the MRSA nasal swab culture (+) and (−) groups. Positive drain tip cultures were found in 382 cases (8.4%), 28 of which developed SSI. There was a significant difference in the SSI positivity rate between the drain tip culture (+) and (−) groups. The sensitivity of drain tip culture was 29.8% and the specificity was 92.1%. In 16 of the 28 patients in the SSI (+) group with positive drain cultures, the same bacteria were isolated from the surgical site, giving a bacteria matching rate of 57.1%.

Conclusion.

MRSA nasal swab and drain tip cultures were not useful for predicting SSI. However, drain tip culture had a high positivity rate in the SSI group and the coincidence rate for the causative pathogen was relatively high.

Level of Evidence: 4