bluuebunny/crossref_metadata_2025 huggingface dataset:
Ambiguity, death determination, and the dead donor rule
Authors: Lyon Will
Published: July 2018

The dead donor rule states that organ donors must be declared dead before any vital organs are removed. Recently, scholars and physicians have argued for the abandonment of the dead donor rule, based on the rule’s supposed connection with the concept of brain death, which they view as a conceptually unreliable definition of death. In this essay, I distinguish between methods of death determination and the question of whether or not the dead donor rule should be a guiding principle of organ transplant ethics. In principle, the dead donor rule does not rely on any one definition of death, but only prohibits the taking of vital organs before a patient is declared dead. In light of this distinction, I argue that even if the dead donor rule is tied to brain death in practice, conceptual disagreement about brain death does not provide grounds for rejection of this rule. I then present evidence in support of the consistency and reliability of the diagnosis of brain death. I show that, when performed carefully and under specific clinical circumstances, the diagnosis of brain death is considered by most neurologists to be reliable. Finally, I argue that, without the dead donor rule, organ transplantation programs would become susceptible to violations of the ethical principle of respect for persons.
Neoliberal reform and family engagement in schools: An intersectional gender analysis
Authors: Nygreen Kysa
Published: July 2018

This article presents an exploration of the work of family engagement in a racially- and linguistically-diverse, high-poverty, urban school district in a state of continuous neoliberal reform. Drawing from qualitative research methods, it is argued that family engagement is being reshaped by the imperatives of educational neoliberalization while, at the same time, remaining out of touch with the needs and concerns of families who are racially stigmatized, linguistically diverse, and experiencing extreme economic insecurity. It is further argued that school personnel charged with family engagement carry out exploited, invisible, and emotional tasks that increase in quantity and intensity as the social safety net declines under neoliberalism. Applying an intersectional gender analysis of emotional labor and the re-privatization of social reproduction offers an illustration of how family engagement in neoliberal schools both exploits and reinforces hierarchies of race–class–gender while obscuring these processes through neoliberal discourses of individual responsibilization.
Friendship as a Political Concept: A Groundwork for Analysis
Authors: Smith Graham M
Published: July 2018

What kind of a concept is friendship, and what is its connection to politics? Critics sometimes claim that friendship does not have a role to play in the study of politics. Such objections misconstrue the nature of the concept of friendship and its relation to politics. In response, this article proposes three approaches to understanding the concept of friendship: (1) as a ‘family resemblance’ concept, (2) as an instance of an ‘essentially contested’ concept, and (3) as a concept indicating a problématique. The article thus responds to the dismissal of friendship by undertaking the groundwork for understanding what kind of a concept friendship might be, and how it might serve different purposes. In doing so, it opens the way for understanding friendship’s relation to politics.
Inclusion Wheel: Tool for Building Capacity and Public Health Leaders to Serve People With Disabilities
Authors: Griffen Adriane K. , Risley Kristina , Petros Michael , Welter Christina R.
Published: July 2018

Public health leaders need to influence change to serve underserved populations, such as people who have a disability. Action research was conducted with a community of practice (CoP) from Ohio to examine readiness, capacity building, and capacity factors needed for public health partners to more fully include people who have a disability (PWD) in state smoking cessation efforts. Five conditions fostered readiness, capacity building, and capacity among public health partners to include PWD: (1) successful timing of effort, (2) facilitation of discussions, (3) systematic reflection, (4) sufficient support, and (5) personal commitment of participants. Nine factors of readiness, capacity building, and capacity influenced inclusion of PWD: (1) positive perception and quality interactions with partners, (2) contact with organizations, (3) recognition of need to coordinate, (4) engagement in a network, (5) practical collaboration experience, (6) continuing education, (7), critical reflection time, (8) dedicated staff, and (9) knowledge of priority population. Readiness, capacity, and capacity building were interconnected and supported inclusion of PWD in public health efforts. Ohio public health partners used these factors and conditions to achieve the first mandatory disability awareness training for all National Jewish Health Quitline counselors. Future efforts addressing other specific demographic groups that experience health disparities can use these findings.
Evolutionary Music Education: Robert W. Claiborne and The Way Man Learned Music (1927)
Authors: Hanson Josef
Published: July 2018

The purpose of this study was to explore and document The Way Man Learned Music (1927), a method written by lawyer, Marine captain, educator, and political leader Robert Watson Claiborne (1888–1966). Drawing influence from Ernst Haeckel and G. Stanley Hall’s theories of recapitulation, Claiborne designed a comprehensive and sequential method where students engage in primitive stages of music-making by building and playing their own instruments, including drums, pan pipes, and small marimbas. Storytelling, dance, folk music from around the world, and performance of authentic Western art music combine to form a dramatic rendering of global musical life. As such, the method bears a strong resemblance to the more widely celebrated contributions of Satis Coleman (1876–1961). Analysis of primary and secondary sources as well as interview data illuminated the complexity of Claiborne’s path to music education. Namely, Claiborne’s homosexuality, which formed the basis of an inconclusive court-martial trial impelling his departure from military service, complicated his ability to find work as a lawyer, spurring him to pursue music education. Although a product of its time, Claiborne’s method serves as a testament to active, experiential learning that is child-centered.
Contextualizing LGB Youth’s Experiences With Victimization and Risky Behaviors: A Qualitative Approach to General Strain Theory
Authors: Button Deeanna M.
Published: July 2018

This study uses 20 in-depth interviews with lesbian, gay, and bisexual (LGB) young adults aged 18 to 25 years to integrate theoretical constructs from the sociology of sexuality with Agnew’s general strain theory (GST). This approach provides theoretical context to LGB youth’s experiences with victimization and risky behaviors. The use of qualitative data provides a deeper understanding of LGB youth’s experiences with heteronormativity, heterosexism, and homophobia, and how these structural-level processes shape interactional- and individual-level experiences. Integrating sexuality research and GST helps clarify interconnected processes that occur at multiple levels of social life, providing a more complete picture of LGB experiences.
Exploring Structural, Sociocultural, and Individual Barriers to Alcohol Abuse Treatment Among Hispanic Men
Authors: Valdez Luis A. , Garcia David O. , Ruiz John , Oren Eyal , Carvajal Scott
Published: July 2018

Hispanic men have poor access to alcohol abuse treatment, low treatment engagement, and low treatment completion rates despite the contrasting burden of alcohol-related consequences they face. The purpose of this study was to examine Hispanic male perspectives regarding alcohol abuse treatment-seeking behaviors and the structural, sociocultural, and individual factors that may influence initiation and continued engagement in treatment in this population. Individual interviews were conducted with a sample of 20 Hispanic men (age: 44.6 ± 11.3 years). Thematic analysis was completed using a hybrid deductive–inductive approach centered in an a priori codebook that was further supplemented with iterative exploration of transcripts. Results suggested treatment-seeking behaviors were highly influenced by (a) structural factors related to poor treatment access, as well as lack of linguistic- and cultural-responsiveness of available treatment; (b) sociocultural factors related to difficulties problematizing alcohol abuse due to lack of community awareness, societal normalization of consumption, and stigmatization of alcohol abuse treatment; and (c) individual factors related to lack of individual knowledge. This work highlights the perceived lack of congruency between available treatment and the linguistic, cultural, and gender norms of Hispanic men. There is need for responsive treatment strategies that comprehensively consider the gendered- and sociocultural-factors that govern treatment seeking and engagement behaviors. Findings also suggest a need for targeted alcohol abuse awareness building efforts in the Hispanic community. Specifically, the detrimental effects of alcohol-related problems and potential benefits of treatment should be addressed in order to diminish social stigma of abuse and of treatment.
Modified rule of mixtures and Halpin–Tsai model for prediction of tensile strength of micron-sized reinforced composites and Young’s modulus of multiscale reinforced composites for direct extrusion fabrication
Authors: Luo Zirong , Li Xin , Shang Jianzhong , Zhu Hong , Fang Delei
Published: July 2018

A modified rule of mixtures is required to account for the experimentally observed nonlinear variation of tensile strength. A modified Halpin–Tsai model was presented to predict the Young’s modulus of multiscale reinforced composites with both micron-sized and nano-sized reinforcements. In the composites, both micron-sized fillers—carbon fibers—and nano-sized fillers—rubber nanoparticles and carbon nanotubes—are added into the epoxy resin matrix. Carbon fibers can help epoxy resins increase both the tensile strength and Young’s modulus, while rubber nanoparticles and carbon nanotubes can improve the toughness without sacrificing other properties. Mechanical experiments and scanning electron microscopy observations were used to study the effects of the micron-sized and nano-sized reinforcements and their combination on tensile and toughness properties of the composites. The results showed that the combined use of multiscale reinforcements had synergetic effects on both the strength and the toughness of the composites.
Research on the control strategy of power train systems for hybrid hydraulic excavators
Authors: Chen Qihuai , Lin Tianliang , Ren Haoling , Fu Shengjie
Published: July 2018

Hybrid power technology is a practicable method for construction machinery to improve fuel utilization and reduce emissions. In this article, in order to achieve the maximum degree of energy conservation for hybrid hydraulic excavator, a study on a control strategy of the hybrid power train system for a 20-t hybrid hydraulic excavator is conducted. A rule-based method which stabilizes the engine operating points in high-efficiency area and maintains the state of charge of the ultra-capacitor in a feasible operating range is presented. Meanwhile, to improve the reliability of the ultra-capacitor, a two-stage state of charge constraint is applied. To validate the effectiveness of the control strategy, a hybrid power train system simulation loading experiment platform is built. The working characteristics and the energy conservation characteristics of the hybrid power train system are explored. Actual load profiles measured from a 20-t traditional excavator are measured and applied in the system. The experimental results show that the proposed control strategy for the hybrid power train system can improve the fuel economy of the hybrid hydraulic excavator. Meanwhile, dynamic performance of the hybrid power train system is better than that of the traditional excavator.
Optimal design of three-dimensional non-uniform nylon lattice structures for selective laser sintering manufacturing
Authors: Jin Xin , Li Guo Xi , Zhang Meng
Published: July 2018

As a kind of novel multifunctional structure with three-dimensional pores characterized by low relative density, lattice structures can attain a lightweight design while maintaining high specific mechanical properties in three-dimensional solid structures. Focusing on the challenge of finding the optimal design of lattice structures in the design object, a design and modeling method of non-uniform three-dimensional lattice structures is proposed while ensuring the selective laser sintering manufacturability. Optimization for cell type, cell size, and strut size distribution of lattices is specified with the mechanical properties analyzed and the material model calculated beforehand. The manufacturing constraints are analyzed and expressed in topology optimization and the optimal distribution of topology optimization results is mapped to the strut size distribution of lattice cells. The rapid and automatic computer-aided design modeling of optimized structures is realized by the parametric definition and assembling of lattice components. Finally, the non-uniform structures are successfully manufactured by selective laser sintering and it is shown by means of finite element analysis and experiments that the proposed design approach can improve the mechanical performance compared to the uniform lattice structure under the same weight reduction. And for the design object in this study, body-centered structure with cell size [Formula: see text]mm is chosen as the optimal cell type and cell size under the given selective laser sintering manufacturing constraints.
Optimizing maintenance decisions in railway wheelsets: A Markov decision process approach
Authors: Braga Joaquim AP , Andrade António R
Published: July 2018

This article models the decision problem of maintaining railway wheelsets as a Markov decision process, with the aim to provide a way to support condition-based maintenance for railway wheelsets. A discussion on the role of the railway wheelsets is provided, as well as some background on the technical standards that guide maintenance decisions. A practical example is explored with the estimation of Markov transition matrices for different condition states that depend on the wheelset diameter, its mileage since last turning action (or renewal) and the damage occurrence. Bearing in mind all the possible maintenance actions, an optimal strategy is achieved, providing a map of best actions depending on the current state of the wheelset.
Start a fire, kill the bug: The role of platelets in inflammation and infection
Authors: Deppermann Carsten , Kubes Paul
Published: July 2018

Platelets are the main players in thrombosis and hemostasis; however they also play important roles during inflammation and infection. Through their surface receptors, platelets can directly interact with pathogens and immune cells. Platelets form complexes with neutrophils to modulate their capacities to produce reactive oxygen species or form neutrophil extracellular traps. Furthermore, they release microbicidal factors and cytokines that kill pathogens and influence the immune response, respectively. Platelets also maintain the vascular integrity during inflammation by a mechanism that is different from classical platelet activation. In this review we summarize the current knowledge about how platelets interact with the innate immune system during inflammation and infection and highlight recent advances in the field.
Transcriptional up-regulation of the TGF-β intracellular signaling transducer Mad of Drosophila larvae in response to parasitic nematode infection
Authors: Patrnogic Jelena , Heryanto Christa , Eleftherianos Ioannis
Published: July 2018

The common fruit fly Drosophila melanogaster is an exceptional model for dissecting innate immunity. However, our knowledge on responses to parasitic nematode infections still lags behind. Recent studies have demonstrated that the well-conserved TGF-β signaling pathway participates in immune processes of the fly, including the anti-nematode response. To elucidate the molecular basis of TGF-β anti-nematode activity, we performed a transcript level analysis of different TGF-β signaling components following infection of D. melanogaster larvae with the nematode parasite Heterorhabditis gerrardi. We found no significant changes in the transcript level of most extracellular ligands in both bone morphogenic protein (BMP) and activin branches of the TGF-β signaling pathway between nematode-infected larvae and uninfected controls. However, extracellular ligand, Scw, and Type I receptor, Sax, in the BMP pathway as well as the Type I receptor, Babo, in the activin pathway were substantially up-regulated following H. gerrardi infection. Our results suggest that receptor up-regulation leads to transcriptional up-regulation of the intracellular component Mad in response to H. gerrardi following changes in gene expression of intracellular receptors of both TGF-β signaling branches. These findings identify the involvement of certain TGF-β signaling pathway components in the immune signal transduction of D. melanogaster larvae against parasitic nematodes .
This “Modern Epidemic”: Loneliness as an Emotion Cluster and a Neglected Subject in the History of Emotions
Authors: Bound Alberti Fay
Published: July 2018

Loneliness is one of the most neglected aspects of emotion history, despite claims that the 21st century is the loneliest ever. This article argues against the widespread belief that modern-day loneliness is inevitable, negative, and universal. Looking at its language and etymology, it suggests that loneliness needs to be understood firstly as an “emotion cluster” composed of a variety of affective states, and secondly as a relatively recent invention, dating from around 1800. Loneliness can be positive, and as much a part of the body as the mind. Using a longue durée approach, I argue that we cannot understand loneliness as a “modern epidemic” without considering its history, its meanings, its practice, and its links with the body.
Author Reply: We Don’t Yet Know What Emotions Are (But Need to Develop the Methods to Find Out)
Authors: Adolphs Ralph , Andler Daniel
Published: July 2018

Our approach to emotion emphasized three key ingredients. (a) We do not yet have a mature science of emotion, or even a consensus view—in this respect we are more hesitant than Sander, Grandjean, and Scherer (henceforth “SGS”) or Luiz Pessoa (henceforth “LP”). Relatedly, a science of emotion needs to be highly interdisciplinary, including ecology, psychology, neuroscience, and philosophy. (b) We recommend a functionalist view that brackets conscious experiences and that essentially treats emotions as latent variables inferred from a number of measures. (c) But our version of functionalism is not definitional or ontological. It is resolutely methodological, in good part because it is too early to attempt definitions.
Author Reply: Placing Emotion Within a Science of Brain and Behavior
Authors: Pessoa Luiz
Published: July 2018

In this response, I suggest that the focus of “emotion” researchers should be more on striving to develop a science of brain and behavior than on deciding what is the proper status of emotion. Because structure and function are closely intertwined in biological systems, advancing our understanding of complex behaviors will necessitate researching their brain substrates.
The Relationship Between Polyethylene Insert Size and Complications in Total Ankle Replacement
Authors: Cottom James M. , Douthett Steven M. , McConnell Kelly K. , Plemmons Britton S.
Published: July 2018

The purpose of this study was to compare complication rates after total ankle replacement in 2 groups of patients based on polyethylene insert size. The total cohort was divided into 2 groups based on insert size. Group 1 included patients with polyethylene insert size less than 10 mm in thickness. Group 2 included patients with polyethylene insert sizes 10 mm and larger. Available charts were reviewed for patients who underwent primary total ankle arthroplasty by one surgeon. Patient demographics, polyethylene insert size, implant used, concomitant procedures, postoperative complications, and patient-reported outcome scores were recorded. One hundred patients were available for follow-up and were included in this study, which ranged from March 2012 to July 2017. The average follow-up was 31.3 months (range = 10-60 months). Forty-eight females and 52 males were included in this study. There were a total of 63 patients in group 1 and 47 patients in group 2. The total complication rate for patients in group 1 was 11.1% (7/63), and in group 2 it was 16.2% (6/32). There was no statistical significance in complication rates when comparing the 2 groups (P = 0.5427). All patients underwent at least one concomitant procedure at the time of initial ankle replacement. Our findings show that total ankle replacement complication rates are equal when comparing large polyethylene inserts commonly utilized to correct deformities, versus small polyethylene inserts commonly utilized in primary resurfacing.

Levels of Evidence: Level IV, Retrospective comparative study
Social Perception of Forecasters: People See Forecasts of Future Outcomes as Cues to Forecasters’ Desires, Attitudes, and Identity
Authors: Stavrova Olga
Published: July 2018

While people’s forecasts of future outcomes are often guided by their preferences (“desirability bias”), it has not been explored yet whether people infer others’ preferences from their forecasts. Across 3 experiments and overall 30 judgments, forecasters who thought that a particular future outcome was likely (vs. unlikely) were perceived as having a stronger preference for this outcome. Individuals were more likely to infer preferences from forecasts in the presence of cues facilitating internal attributions and in case of outcomes characterized by an actual positive empirical association between desirability and likelihood judgments. Finally, making future forecasts inconsistent (vs. consistent) with one’s stated preferences made observers doubt forecasters’ expressed preferences and identity. Overall, these findings suggest that social observers tend to interpret future forecasts as cues to others’ identity, values, and attitudes.
Exposure to second-hand smoke among secondary school-going adolescents: Findings from the Malaysian Adolescent Health Risk Behaviour (MyAHRB) study
Authors: Lim Hui Li , Teh Chien Huey , Kee Chee Cheong , Mohd Ghazali Sumarni , Pan Sayan a/l , Lim Kuang Hock
Published: July 2018

Background:

Exposure to second-hand smoke (SHS) is one of the main causes of morbidity and it has been proven to be associated with an increased likelihood of smoking initiation among adolescents. Nonetheless, evidence on SHS exposure among Malaysian adolescents is scarce. Therefore, this article aims to demonstrate the magnitude and factors associated with SHS exposure among school-going adolescents in selected secondary schools in Peninsular Malaysia.

Methods:

Data were derived from the Malaysian Adolescent Health Risk Behaviour (MyAHRB) study conducted in 2013. A total of 2599 adolescent were recruited into the study using a two-stage proportionate-to-size sampling method. Data were obtained from self-administered questionnaires. Descriptive analysis and multivariable logistic regression were performed to determine the risk factors/predictors associated with SHS.

Results:

More than half of the respondents had been exposed to SHS during the last one week (56.4%), and SHS exposure was significantly higher among respondents who smoked (94.0% vs. 49.9%, p <0.001). Multivariable analysis revealed that the likelihood of exposure to SHS was higher among those who smoked (adjusted odds ratio (aOR) 12.90, 95% confidence interval (CI): 8.01–20.4), had at least one parent/guardian who smoked (aOR 5.49, 95% CI: 4.41–6.94) and adolescents of Malay descent (aOR 2.10, 95% CI: 1.68–2.63).

Conclusion:

Our findings suggested that the effectiveness of anti-smoking measures implemented in recent years to protect adolescents from the health risks of passive smoking were less evident. Therefore, educational and awareness programmes that emphasize the negative health impacts of SHS exposure on Malaysian adolescents, particularly when among smoking adults, should be intensified to help in preventing adoption of smoking behaviours among adolescents.
Clinical profile and outcome of neonates with congenital diaphragmatic hernia: A 16-year experience from a developing country
Authors: Rattan Kamal Nain , Dalal Poonam , Singh Jasbir
Published: July 2018

Recent advances in the perinatal interventions for neonates with congenital diaphragmatic hernia have remarkably improved the outcome in developed countries, but high mortality for such cases continues to be a challenge in resource-poor settings. This study examines clinical profiles and short-term outcome of neonates with congenital diaphragmatic hernia, using a retrospective analysis of medical records of neonates operated for congenital diaphragmatic hernia at a tertiary care center in North India from January 2001 to December 2016. Forty-two neonates were operated during the study period with male:female ratio = 1.6:1. Postoperative survival rate was 69% (29/42). Average birth weight in the survivors was 2528±267 g as compared with 2132±309 g in the non-survivors. The average gestational age in the two groups was 37.2±0.8 weeks and 34.8±1.8 weeks respectively. Twenty-one patients presented in the initial 48 h of life, out of them 52% (11/21) survived. Congenital heart diseases were associated with seven and malrotation of the gut in five neonates. The most significant factors resulting in the unfavorable outcome were preterm gestation, low birth weight, hypothermia and shock at presentation, the onset of symptoms <48 h of life, liver-up, need of postoperative inotropes and mechanical ventilation. In addition to establishing advanced therapeutic modalities, good antenatal screening, better awareness in peripheral health workers about the malformation leading to timely referral, well-equipped inter-hospital and intra-hospital transport facilities and development of level III neonatal intensive care units can improve survival in neonates with congenital diaphragmatic hernia in developing countries.
Research on urban residents’ acquisitions of second sets of housing from a life-course perspective
Authors: Wu Kaize
Published: July 2018

This study examines how macro-social and micro-social and economic factors at different life stages affect people’s decisions about purchasing secondary residential property. I suggest several possible explanations, such as cohort opportunity, property market opportunity, elite advantage, family resource investment, and rational choice. Using discrete-time event history analysis, I look into the data collected from investigation of the housing conditions of urban residents of Guangzhou in 2010 and find that factors such as elite advantage and family resource investment become much more significant in purchasing a second property, while the impact of cohort opportunity and work unit subsidies diminishes. Housing marketization has changed property wealth accumulation in China from institutional resource distribution to market resource accumulation. It has changed housing purchase means from relying on work unit support to depending on personal and family financial capability. The early stage of market-oriented reform was able to offer property ownership opportunities to different social strata; however, deepening marketization and wealth redistribution have worsened housing inequality among different social groups as well as within the younger cohorts. Any future housing reform should endeavor to prevent further housing polarization between the rich and the poor.
‘Neo-agents’: A study of village governance under the ‘Projects to Villages’ model
Authors: Li Zupei
Published: July 2018

The program ‘Projects to Villages’ ( xiangmu jincun) is an important means by which the Chinese government distributes resources to grassroots villages, and it has gained popularity in recent years. ‘Projects to Villages’ has introduced a new group of players into the village governance body—village cadres designated in this study as ‘neo-agents’. The term explains a newly emerged grassroots power base that was created by the government’s ‘Projects to Villages’ initiatives. With the intense competition for projects among villages, people with the right political and personal skills, broad networks, and less vested interest in the village have been able to step onto the political stage and gain power. Contrary to the essential need for developing long-term effective rural leadership, these neo-agents practice a type of short-term, interest-focused governance. They do not provide a solution to the governance quandary experienced in villages since the rural taxation reform in 2002; instead, given the availability of state resources, they help further consolidate the existing village power structure. The study also compares neo-agents with the traditional power agents of gentry, local elites, and government officials. Four aspects of governance, including foundation of authority, mechanism of power transfer, structure of governance, and effectiveness of governance are discussed in hopes of stimulating further academic and practical interest in the subject.
‘An interesting paper but not sufficiently theoretical’: What does theorising in social research look like?
Authors: Hammond Michael
Published: July 2018

This article explores the concept of theorising in social research: what is theorising; how does theorising look to those doing it and how can it be explained as a practice. The article draws on different sources, including accounts of theory and theorising in the literature as well as first-hand reporting by academics. A view is reached of theorising as a personal undertaking involving a commitment to comprehend the world. It is argued that theorising is driven by the identification of interesting problems (practical or theoretical or both) and a motivation to solve them. Theorising involves a shift of awareness from subsidiary to focal and such a shift allows a more abstract level of understanding. Theorising tends to be an individual undertaking which draws on personal knowledge, but it is only made possible by psychological tools which have been handed down from the past, ones which need to be accessed, understood and adapted. Theorising requires a disciplined creativity in which the imagination is channelled into finding solutions that are compatible with observed data.
Complexities and Contradictions in Policy Implementation: Lived Experiences of Three School Principals in South Africa
Authors: Bayeni Sibusiso Douglas , Bhengu Thamsanqa Thulani
Published: July 2018

In this article, we discuss and highlight the complexities and contradictions that emerged from our analysis of data generated from three school principals from a rural community in South Africa. School principals play an intermediary role in the policy-practice sphere. Their role puts them in a difficult position, where they have multiple accountabilities. Using a template analytical framework, the findings suggest that their intermediary role in policy implementation is fraught with complexities, challenges, and contradictions. The findings further indicate that faced with conflicting demands of the government and that of their local contextual realities, principals make choices about which policy to implement according to government’s expectations and which ones not to. We conclude that an alternative understanding of policy implementation as a form of negotiation and compromise-seeking processes among stakeholders at the school level is desirable.
High School Athletes’ Reports of Confirmation as a Function of Starting Status and Leader–Member Exchange
Authors: Cranmer Gregory A. , Arnson Emily , Moore Andrew , Scott Alexander , Peed Joshua
Published: July 2018

Previous research indicates that athletes report receiving disparate levels of confirmation, which is consequential given the psychological, emotional, and cognitive benefits of being confirmed. This article explains head coaches’ use of confirmation, which is comprised of accepting and challenging communication, as a function of athletes’ roles and leader–member exchange (LMX). Data obtained from 197 high school athletes—representing 17 sports and from 16 states—substantiated that starters receive more recognition and acknowledgement of their efforts and accomplishments (i.e., acceptance) but are not more likely to receive communication that seeks the refinement of their potential (i.e., challenge). LMX with head coaches, however, accounted for much larger portions of variance in reports of receiving confirmation, with in-group relationships being predictive of greater amounts of confirmation. These results indicate that confirmation is received as a function of the roles of athletes and their interpersonal relationships with coaches. Such findings provide mechanisms to explain disparate experiences of confirmation and connect two theoretical bodies of literature in a manner that intersects the organizational and interpersonal processes of coaching.
Intrawound Treatment for Prevention of Surgical Site Infections in Instrumented Spinal Surgery: A Systematic Comparative Effectiveness Review and Meta-Analysis
Authors: Lemans Justin V. C. , Wijdicks Sebastiaan P. J. , Boot Willemijn , Govaert Geertje A. M. , Houwert R. Marijn , Öner F. Cumhur , Kruyt Moyo C.
Published: July 2018

Study Design:

Systematic review and meta-analysis.

Objectives:

To determine the efficacy of intrawound treatments in reducing deep surgical site infections (SSIs) in instrumented spinal surgery.

Methods:

The electronic databases MEDLINE, EMBASE, and Cochrane were systematically searched for intrawound treatments for the prevention of SSIs in clean instrumented spine surgery. Both randomized controlled trials and comparative cohort studies were included. The results of included studies were pooled for meta-analysis.

Results:

After full text- and reference screening, 20 articles were included. There were 2 randomized controlled trials and 18 observational studies. Sixteen studies investigated the use of intrawound antibiotics, and 4 studies investigated the use of intrawound antiseptics. The relative risk of deep SSI for any treatment was 0.26 (95% confidence interval [CI] 0.16-0.44, P < .0001), a significant reduction compared with controls receiving no treatment. For patients treated with local antibiotics the relative risk was 0.29 (95% CI 0.17-0.51, P < .0001), and patients treated with local antiseptics had a relative risk of 0.14 (95% CI 0.05-0.44, P = .0006).

Conclusions:

Both the use of antibiotic and antiseptic intrawound prophylactics was associated with a significant 3 to 7 times reduction of deep SSIs in instrumented spine surgery. No adverse events were reported in the included studies.
Bone Bruises in Children and Adolescents Not Associated With Ligament Ruptures
Authors: Gómez Jorge E. , Molina Daren D. , Rettig Shaylon D. , Kan J. Herman
Published: July 2018

Background:

Clinical characteristics of uncomplicated bone bruises (ie, not associated with a ligament rupture, meniscal tear, or fracture of the knee) in young athletes have scarcely been reported.

Purpose:

To identify mechanisms of injury, characterize bone bruise patterns, and identify clinical factors relating to recovery in young patients suffering uncomplicated bone bruises about the knee.

Study Design:

Case series; Level of evidence, 4.

Methods:

A review of clinical records and magnetic resonance imaging (MRI) findings of patients seen at a single institution was completed.

Results:

We identified 62 children and teenagers (mean age, 13.9 years; range, 8-18 years) who had a total of 101 bone bruises on MRI. The injuries occurred during a variety of organized and recreational sporting activities, the most common being football, basketball, and soccer. The majority (61.4%) of bone bruises occurred as a result of noncontact mechanisms. Patients reported a mean pain scale score of 6.3 of 10 (range, 2-10) on presentation. Frequent clinical findings included non–joint-line tenderness (64.5%), limited range of motion (58.1%), joint-line tenderness (54.8%), and positive meniscal signs (50.0%). The majority of bone bruises (61.4%) were located medially, and the most common bone bruise type was subcortical (58.4%), followed by medullary/reticular (35.6%) and articular impaction (5.9%). The only factor related to time to recovery was mechanism of injury; patients reporting a noncontact mechanism required significantly more time to recover than those reporting a contact mechanism (mean, 99.7 ± 74.8 vs 65.7 ± 38.8 days, respectively; F = 3.753, P = .049).

Conclusion:

In this case series of 62 pediatric patients with non–anterior cruciate ligament (ACL) bone bruises, the majority occurred in the medial compartment, suggesting that these bone bruises result from a mechanism distinct from the pivot-shift mechanism, classically thought to cause ACL injuries.
Fatigue Increases ACL Injury Risk in Youth Athletes: Risk Assessment Study Using Drop-jump Test
Authors: Fidai Mohsin S. , Okoroha Kelechi , Meldau Jason E. , Borowsky Peter A. , Meta Fabien , Lizzio Vincent A. , Redler Lauren H. , Moutzouros Vasilios , Makhni Eric C.
Published: July 2018

Objectives:

The impact of fatigue on injury risk to the anterior cruciate ligament (ACL) in adolescent athletes is unknown. Identifying athletes who demonstrate increased risk for injury may help determine who would benefit from early neuromuscular control intervention for injury prevention. The goal of this study was to determine if fatigue increases ACL injury risk in adolescent athletes using the drop-jump test to assess dynamic valgus.

Methods:

Youth and adolescent competitive athletes were recruited for this video analysis study. Participants were recorded performing the standard drop-jump test assessing dynamic valgus on landing three times. They then completed a standardized fatigue protocol consisting of a timed period of high-intensity aerobic tasks. A set amount of fatigue was quantified and achieved using a maximum vertical jump, which was compared to pre-fatigue values. The drop-jump test was then repeated three additional times post-fatigue. All drop-jump recordings (six in total) were randomized by order and scored for dynamic knee valgus by three independent reviewers. A multivariable analysis was performed to assess the correlation between demographic variables and injury risk.

Results:

Forty-seven female patients and thirty-eight male athletes were included in the study. The average age was 15.4 years (age 14-18). Athletes were found to have significantly higher ACL injury risk post-fatigue when compared to pre-fatigue (p = .001). Thirty-five athletes were found to change from low/medium injury risk pre-fatigue to medium/high risk post fatigue. No demographic variables were found to contribute to ACL injury risk.

Conclusion:

In adolescent athletes, fatigue appears to increase risk of ACL injury through drop-jump testing. Age, BMI, and hip width were not found to contribute to ACL injury risk. Implementation of neuromuscular or conditioning programs for at-risk athletes may reduce injury risk.
Utility of Merchant View Radiographs for Assessment of TT-TG: A Comparison to MRI
Authors: Bernholt David , Lamplot Joseph D. , Eutsler Eric , Nepple Jeffrey J.
Published: July 2018

Objectives:

Lateralization of the tibial tubercle plays a significant role in the pathophysiology of patellar instability and is most often assessed by the tibial tubercle to trochlear groove distance (TT-TG) measured on CT or MRI with the knee in extension. However, tracking of the patella in 30 to 45 degrees of flexion has been suggested to be of greater clinical significance. Merchant radiographs can demonstrate the position of the tibial tubercle relative to the trochlear groove in this range of flexion and thus may serve as a valuable tool in the assessment of patellar tracking. The purpose of the current study was (1) to validate radiographic assessment of the merchant view TT-TG and (2) to determine the correlation with MRI-based measurements.

Methods:

To validate Merchant TT-TG as a marker of the position of the tibial tubercle, 41 patients between the ages of 10-18 had standardized Merchant radiographs in 45 degrees flexion yielding imaging of 82 knees. Lead markers were placed upon the skin centered over the tibial tubercle based on palpation. Radiographs were collected and analyzed. The TT-TG was measured as the distance between lines centered over the deepest point of the trochlear groove and the center of the tibial tubercle and perpendicular to the anterior condylar axis. In order to correlate Merchant TT-TG to MRI TT-TG, 16 additional patients were added to reach a total of 30 patients with a Merchant radiograph and MRI, as power calculation determined 29 knees needed to detect a Pearson correlation coefficient (PCC) of .500. There was excellent interobserver reliability between two readers for Merchant TT-TG with and without use of a radiographic marker (ICC = .975 and .923 respectively).

Results:

The tibial tubercle could be identified on Merchant radiograph in 67 images (81.7%). Merchant TT-TG measured with use of a marker was very strongly correlated measurement based on bony landmarks alone (PCC = .848). The Merchant TT-TG measured with bony landmarks alone was strongly correlated to MRI TT-TG (PCC = .602). The strength of this correlation was increased by standardizing TT-TG by patellar width (PCC = .710). MRI TT-TG was increased in patients with patellar instability at 13.9 mm compared to 10.5 mm (p <.01); Merchant TT-TG was also increased in patients with patellar instability at 9.1 mm compared to 1.9 mm (p < .001).

Conclusion:

Standardized Merchant radiographs without radiographic markers allow for assessment of TT-TG in the majority of patients. Merchant TT-TG strongly correlates with MRI TT-TG but measured 5-8 mm smaller than MRI TT-TG.
The Role of Abnormal Tibiofemoral Rotation in Pediatric and Adolescent Patellar Instability
Authors: Bernholt David , Lamplot Joseph D. , Eutsler Eric , Nepple Jeffrey J.
Published: July 2018

Objectives:

Abnormal patellofemoral tracking has been implicated in patellar instability and can be influenced by the bony anatomy and alignment of the femoral trochlea, patella, and tibial tubercle. Tibiofemoral joint rotation has been recently suggested to play a role in patellofemoral kinematics but there has been little investigation of its contribution to patellar instability, including in pediatric and adolescent patients.

Methods:

A retrospective case-control design was utilized. 30 patients aged 9-18 with a prior patellar dislocation and an MRI of the involved knee were included. Cases were matched for age and gender with controls without patellar instability. Patients with ACL tears, tibial eminence or tubercle fractures, or prior surgery in the involved extremity were excluded. There was no difference in gender, age, height, but BMI was higher in the case group. MRI images taken with knee in extension were analyzed. Tibial tubercle-trochlear groove (TT-TG), tibial tubercle-posterior cruciate ligament (TT-PCL), and tibiofemoral rotation were measured. All measurements were performed by a single reader with excellent intra and interobserver reliability for tibiofemoral rotation (ICC-intra > .954 and ICC-inter > .905) demonstrated in a subset of patients.

Results:

The TT-TG was increased in patients with patellar instability at 16.3 mm compared to 10.9 mm in controls (p <.001) as was also the TT-PCL at 19.4 mm cases versus 17.6 mm (p=0.02). Tibiofemoral rotation was increased in patients with patellar instability with a mean 6.9° of tibial external rotation compared to 0.8° of tibial internal rotation in controls (p < .001). Overall, 30/41 (75.6%) of patients with patellar instability had tibiofemoral rotation >5° external rotation versus only 3/41 controls (7.3%). There was a strong correlation between TT-TG and tibiofemoral rotation (PCC = 0.776) and a moderate correlation between TT-TG and TT-PCL (PCC = .661). There was only a weak correlation between tibiofemoral rotation and TT-PCL.

Conclusion:

Increased tibiofemoral rotation is present in patients with patellar instability and may play a role in the pathophysiology of patellar instability. Increased tibiofemoral rotation can lead to an increased TT-TG even when TT-PCL is normal.
Minimum Five-Year Outcomes and Clinical Survivorship Following Arthroscopic Double-Row Repair for Full-thickness Supraspinatus Tears
Authors: Pogorzelski Jonas , Fritz Erik M. , Horan Marilee P. , Hussain Zaamin B. , Katthagen Christoph , Godin Jonathan A. , Millett Peter J.
Published: July 2018

Objectives:

Rotator cuff tears lead to significant morbidity due to pain and decreased function. Despite the prevalence of cuff repairs, mid-term outcomes have been scarcely reported. The purpose of this study is to report minimum 5-year outcomes and clinical survivorship after double-row rotator cuff repair for full-thickness supraspinatus tendon tears.

Methods:

Patients at least five years out from arthroscopic double-row repair for a full-thickness cuff tear involving the supraspinatus tendon were included. Pre- and postoperative ASES, SF-12 PCS, QuickDASH, SANE, and satisfaction scores were collected. The relationship between outcomes and (1) tear chronicity, (2) number of tendons involved, (3) type of repair, and (4) primary versus revision procedure, was also evaluated. Kaplan-Meier survivorship analysis was conducted defining failures as progression to revision rotator cuff surgery.

Results:

From November 2005 to February 2012, a total of 189 shoulders were eligible for inclusion. Fifteen shoulders (7.9%) underwent revision rotator cuff repair and were considered failures. Outcomes data were reported at a mean follow-up of 6.6 (range, 5.0-11.0) years. All outcome scores significantly improved from pre- to postoperative time point, including mean ASES (57.9 to 92.9, P < 0.001), SF-12 PCS (43.4 to 52.0, P < 0.001), QuickDASH (35.2 to 10.5, P < 0.001), and SANE scores (61.5 to 86.5, P < 0.001). Acute tears demonstrated significantly better ASES and SANE scores than chronic tears (ASES 95.1 ± 8.9 versus 91.7 ± 11.2, P = 0.025; SANE 89.6 ± 19.9 versus 85.7 ± 21.3, P = 0.042). No other analyzed variable had a significant association with outcomes scores ( P > 0.05). Survivorship analysis demonstrated a postoperative clinical survivorship of the repair of 96.5% at two years and 93.8% at five years (Figure 1).

Conclusion:

Patients can expect excellent clinical outcomes and a low failure rate following arthroscopic double-row repair of full-thickness supraspinatus tears at mid-term follow-up. The repair of acute tears and primary repairs were associated with better postoperative outcomes.