bluuebunny/crossref_metadata_2025 huggingface dataset:
Transparency, Elections, and Pakistani Politicians’ Tax Compliance
Authors: Malik Rabia
Published: October 2019

A growing literature on political accountability focuses on the extent to which voters electorally punish politicians when provided with credible negative information about politicians’ actions. Whether politicians respond to information provision by changing their behavior—thus appearing accountable to voters—is an integral part of this puzzle but has received comparatively little attention. I address this gap by exploiting an unforeseen decision by the Pakistani government to publicly release legislators’ past income tax payments, and measure the effect of the information provision on their tax payments in the following year. Using new data on politicians’ asset ownership and tax payments in a difference-in-differences research design, I provide strong evidence that the pressure to decrease tax evasion was highest for competitively and directly elected legislators. These heterogeneous effects are not explained by differences between legislators or electoral constituencies, supporting the hypothesis that electoral incentives condition legislator responsiveness to information shocks.
A Multiprocess Item Response Model for Not-Reached Items due to Time Limits and Quitting
Authors: Ulitzsch Esther , von Davier Matthias , Pohl Steffi
Published: October 2019

So far, modeling approaches for not-reached items have considered one single underlying process. However, missing values at the end of a test can occur for a variety of reasons. On the one hand, examinees may not reach the end of a test due to time limits and lack of working speed. On the other hand, examinees may not attempt all items and quit responding due to, for example, fatigue or lack of motivation. We use response times retrieved from computerized testing to distinguish missing data due to lack of speed from missingness due to quitting. On the basis of this information, we present a new model that allows to disentangle and simultaneously model different missing data mechanisms underlying not-reached items. The model (a) supports a more fine-grained understanding of the processes underlying not-reached items and (b) allows to disentangle different sources describing test performance. In a simulation study, we evaluate estimation of the proposed model. In an empirical study, we show what insights can be gained regarding test-taking behavior using this model.
A Simulated Walk in Nature: Testing Predictions From the Attention Restoration Theory
Authors: Crossan Corey , Salmoni Alan
Published: October 2019

Attention restoration theory (ART) predicts that top-down processing during everyday activities can cause attentional fatigue and that bottom-up processing that occurs when people experience nature will be restorative. This study exposed participants to three different conditions using a repeated measures design: a control condition during which participants walked on a typical treadmill; a nature condition during which participants walked on the same treadmill, experiencing a simulated nature walk; and a perturbation condition that included the same simulated nature scene but also required top-down processing during the walk. The findings supported ART predictions. As measured by the backward digit span test, top-down processing in a simulated natural environment nullified the restorative effects and the nature condition produced a significant improvement in directed attention performance compared to the control and perturbation conditions after a 10-min walk. These findings offer practical insights to enhance cognitive functioning through simulated natural environments.
Innovative unscented transform–based particle cardinalized probability hypothesis density filter for multi-target tracking
Authors: Li Bo , Yi Huawei , Li Xiaohui
Published: October 2019

Multi-target tracking is widely applied in video surveillance systems. As we know, although the standard particle cardinalized probability hypothesis density filter can estimate state of targets, it is difficult to define the proposal distribution function in prediction stage. Since the robust particles cannot be effectively drawn, the actual tracking accuracy should be enhanced. In this paper, an innovative unscented transform–based particle cardinalized probability hypothesis density filter is derived. Considering the different state spaces, we use the auxiliary particle method and then draw robust particles from the modified distributions in order to estimate the position of targets. Simultaneously, we present the recursion of the optimized Kalman gain to improve the general unscented transform for the velocity estimates. Using the track label, we further integrate them in the framework of the jump Markov model. The simulation results show that the proposed filter has advances in the multi-target tracking scenes. Moreover, the experiments indicate that the filter can track mobile targets with satisfactory results.
Assessment of the load carrying performance of composite cross joints
Authors: Liu Liyang , Cai Mengfei , Geng Xiaoliang , Wang Peiyan , Yue Zhufeng
Published: October 2019

Composite cross joints are common structures in an airframe. When this type of joint is used on an air inlet stiffened structure, it will undertake large bending moment, especially under overpressure of the engine. In this paper, two types of cross joints are tested experimentally and simulated to investigate the load bearing characteristics and make comparative remarks. Four-point bending tests are conducted and the load deflection curves are obtained; besides, the damage pattern of the joints is reported. Based on composite progressive damage model, the numerical simulations have a good agreement with experimental results, revealing the joint failure mechanism and fastener force feature of various joints. The comparative assessment of two types of joints is summarized.
Evolution of Aesthetic Dentistry
Authors: Blatz M.B. , Chiche G. , Bahat O. , Roblee R. , Coachman C. , Heymann H.O.
Published: October 2019

One of the main goals of dental treatment is to mimic teeth and design smiles in a most natural and aesthetic manner, based on the individual and specific needs of the patient. Possibilities to reach that goal have significantly improved over the last decade through new and specific treatment modalities, steadily enhanced and more aesthetic dental materials, and novel techniques and technologies. This article gives an overview of the evolution of aesthetic dentistry over the past 100 y from a historical point of view and highlights advances in the development of dental research and clinical interventions that have contributed the science and art of aesthetic dentistry. Among the most noteworthy advancements over the past decade are the establishment of universal aesthetic rules and guidelines based on the assessment of natural aesthetic parameters, anatomy, and physiognomy; the development of tooth whitening and advanced restorative as well as prosthetic materials and techniques, supported by the pioneering discovery of dental adhesion; the significant progress in orthodontics and periodontal as well as oral and maxillofacial surgery; and, most recently, the implementation of digital technologies in the 3-dimensional planning and realization of truly natural, individual, and aesthetic smiles. In the future, artificial intelligence and machine learning will likely lead to automation of aesthetic evaluation, smile design, and treatment-planning processes.
Precision Health: Bringing Oral Health into the Context of Overall Health
Authors: Tabak L. , Green E. , Devaney S. , Somerman M.
Published: October 2019

Unprecedented advances in genomics, data science, and biotechnology have ushered in a new era of health care in which interventions are increasingly tailored to individual patients. Precision-based approaches extend to oral health, which is essential to overall health. Harnessing the full potential of precision oral health will depend on research to more fully understand the factors that underlie health and contribute to disease—including the human genome, microbiome, epigenome, proteome, and others.
Cognitive-Linguistic Skills Underlying Word Reading and Spelling Difficulties in Chinese Adolescents With Dyslexia
Authors: Chung Kevin Kien Hoa , Lam Chun Bun
Published: October 2019

The present study investigated the co-occurrence of word reading and spelling difficulties for Chinese first language (L1) and English second language (L2) and the role of morphological awareness in word reading and spelling ability across two languages. A total of 110 Hong Kong Chinese-speaking students in Grade 7, including 55 adolescents with dyslexia (28 males, mean age = 152.11 months) and 55 typically developing adolescents (27 males, mean age = 151.85 months) participated. They were assessed on the cognitive-linguistic measures of morphological awareness, phonological awareness, vocabulary knowledge, rapid naming, word reading, and word spelling in L1 and L2. Multivariate analysis of variance showed that compared with the typical students, adolescents with dyslexia had poorer performance in all L1 and L2 measures except the phonological awareness in Chinese. Hierarchical regression analysis indicated that for both groups of students, morphological awareness contributed uniquely to word reading and spelling in L1 and L2; rapid letter naming contributed uniquely to English word spelling. Findings highlight the importance of co-occurring difficulties in L1 and L2 reading and spelling and that morphological awareness may play a critical role in predicting word reading and spelling across languages for Chinese adolescents with dyslexia and those without difficulty.
Students’ acceptance of e-learning approaches in Laboratory Animal Science Training
Authors: Costa Andreia , Costa Ana , Olsson I. Anna S.
Published: October 2019

Different online courses and training programs in Laboratory Animal Science (LAS) have emerged across Europe in recent years. E-learning appears to be a promising solution to achieve flexibility in training while meeting the quality criteria of demanding programs in short training periods. However, little is known about how students perceive e-learning in this context, and there is also a lack of specific and valid instruments to measure this perception. Within an exploratory study framework, the e-learning perception of 229 participants in 15 courses in Portugal using two different online training formats, flipped classroom and full online theoretical training, was assessed. For this purpose, the Questionnaire of E-learning Acceptance (QELA), a 32-item accordance Likert-type scale comprising five subscales was developed to explore the following: how participant perceive e-learning, satisfaction with organization and contents, perception of e-learning relevance for the time management, and its influence for practical training. In general, e-learning was well accepted and perceived to work well and be useful by the majority of courses participants, independently of the course level and e-learning format approach. These results indeed suggest that integration of e-learning is useful in LAS training. We also propose the QELA as a starting point for development and implementation of specific instruments to assess e-learning acceptance in LAS across a wider range of geographical and training contexts.
Do They Really Mean It? Children’s Inference of Speaker Intentions and the Role of Age and Gender
Authors: Rothermich K. , Caivano O. , Knoll L.J. , Talwar V.
Published: October 2019

Interpreting other people’s intentions during communication represents a remarkable challenge for children. Although many studies have examined children’s understanding of, for example, sarcasm, less is known about their interpretation. Using realistic audiovisual scenes, we invited 124 children between 8 and 12 years old to watch video clips of young adults using different speaker intentions. After watching each video clip, children answered questions about the characters and their beliefs, and the perceived friendliness of the speaker. Children’s responses reveal age and gender differences in the ability to interpret speaker belief and social intentions, especially for scenarios conveying teasing and prosocial lies. We found that the ability to infer speaker belief of prosocial lies and to interpret social intentions increases with age. Our results suggest that children at the age of 8 years already show adult-like abilities to understand literal statements, whereas the ability to infer specific social intentions, such as teasing and prosocial lies, is still developing between the age of 8 and 12 years. Moreover, girls performed better in classifying prosocial lies and sarcasm as insincere than boys. The outcomes expand our understanding of how children observe speaker intentions and suggest further research into the development of teasing and prosocial lie interpretation.
Paul’s social network in Colossians: Friends and coworkers in the Lycus Valley
Authors: Miller Amanda C.
Published: October 2019

Various friends and coworkers are associated with the social network of the Apostle Paul and his connection to the church at Colossae: Timothy, Tychicus, Aristarchus, and Archippus. A close examination focuses upon two of these coworkers and friends, Nympha and Epaphras. A careful exploration and analysis of the Colossian social network illustrates that conflicts exist within the social network, especially in the tension between the equality of all as baptized into Christ and the hierarchy of the paterfamilias-run household and empire. The text-segments of Colossians 1 and the household code in Col 3:18–4:1 exemplify the social tensions that existed in the body of Christ, and are instructive about living within the conflicts.
Disarming the rulers and authorities: Reading Colossians in its Roman imperial context
Authors: Wright Arthur M.
Published: October 2019

The scant scholarly discussion that focuses on the relationship between Colossians and the Roman Empire has tended to reduce the relationship to a binary proposition: either Colossians is anti-empire, or it has little to say altogether with regards to empire. Neither perspective captures the complexity of Colossians in this regard. Colossians was not written explicitly for the purpose of opposing Rome’s empire. Yet it does have significant bearing on understanding how to live life faithfully under the dominion of empire. Writing to combat what the author perceives as a dangerous philosophy for the Colossian Christians, the author gives readers a glimpse into a worldview at sharp odds with Roman imperial ideology. The theological and Christological claims of the letter engage with Roman imperial ideology in ways that contest, threaten, and also mimic Roman imperial power.
Optimization design and experimental study of vortex pump based on orthogonal test
Authors: Quan Hui , Guo Ying , Li Rennian , Su Qingmiao , Chai Yi
Published: October 2019

To study the effects of the performance of different types of impeller on the vortex pump, orthogonal test design, which is carried out by combining experimental test and numerical calculation, is adopted to optimize the type of design structure for the impeller in vortex pump. To find out the folding blade angle, the position of the folding point in the whole blade, and whether to wedge folding blade, an orthogonal test scheme with three factors and two levels is designed. A numerical simulation test is conducted for each scheme by analyzing the performance curve of orthogonal test plan to find the optimal performance of the program and analyzing the test data of each scheme to obtain the primary and secondary orders of the impact performance in the angle of folding blades of the vortex pump, the position of folding point of blades, and the wedge shape of blades. The results show that the optical blade type combination is the blade angle R30F60, the folding point is at 2/3 of the whole blade, and the blade does not adopt radial wedge. The optimal combination scheme is 36% higher than the design value at the rated flow head, the efficiency is 18.75% higher than the design value, the high-efficiency zone of the vortex pump is wider, and the performance meets the design requirements. Through orthogonal experimental design, the design cycle of vortex pump can be shortened effectively, the design level of vortex pump can be improved, and the hydraulic model with superior performance can be obtained.
Vitamin D Levels in Children With Recurrent Aphthous Stomatitis
Authors: Nalbantoğlu Burçin , Nalbantoğlu Ayşin
Published: October 2019

Background:

Recurrent aphthous stomatitis is one of the most prevalent oral mucosa diseases and the etiology is unclear. As a potent anti-inflammatory and immunomodulating agent, vitamin D can significantly affect oral cavity homeostasis. However, to the best of our knowledge, no study has been conducted in pediatric population on the potential role of vitamin D in recurrent aphthous stomatitis to date. The aim of the present study is to determine the vitamin D status in recurrent aphthous stomatitis in children.

Methods:

This study is conducted retrospectively. Seventy-two patients with minor recurrent aphthous stomatitis and 70 age-matched healthy controls included in the study. 25-Hydroxyvitamin D levels were measured in all patients using enzyme immunoassay.

Results:

Serum vitamin D levels were 16.4 (8.6) ng/mL in patient group and 23.1 (11.5) ng/mL in healthy controls. There was a statistically significant difference between the groups in terms of serum vitamin D levels ( P = .002). There was no significant correlation between serum vitamin D levels and the severity of the recurrent aphthous stomatitis ( r = 0.54, P = .76).

Conclusions:

Our study showed a significant difference in vitamin D levels between patients with recurrent aphthous stomatitis and the healthy control group. We also found no correlation between vitamin D status and the severity of the disease.
“Their Leaves Shall Be for Healing”
Authors: Copeland Rebecca L.
Published: October 2019

In this article, I expand trauma hermeneutics to encompass ecological trauma, as well as human trauma. I then apply the resulting ecological trauma hermeneutics to Ezekiel in order to offer an alternative explanation of the causes and agents of the trauma suffered by the exiles in Babylon. To do so, I bring the description of the land east of Jerusalem into conversation with a modern example of soil salinization and apply ecological trauma hermeneutics to Ezekiel's vision in 47:1-12, identifying the necessary conditions for healing the ecological trauma of the land and fostering the future resilience of the human-land community.
Intergroup Inequality Heightens Reports of Discrimination Along Alternative Identity Dimensions
Authors: Brown Riana M. , Craig Maureen A.
Published: October 2019

How do members of societally valued (dominant) groups respond when considering inequality? Prior research suggests that salient inequality may be viewed as a threat to dominant-group members’ self and collective moral character. However, people possess multiple social identities and may be advantaged in one domain (e.g., White) while concurrently disadvantaged in another domain (e.g., sexual minority). The present research tests whether individuals may reduce the moral-image threat of being societally advantaged in one domain by highlighting discrimination they face in other domains. Four experiments with individuals advantaged along different dimensions of inequality (race, social class, sexuality) reveal that making such inequality salient evokes greater perceived discrimination faced by oneself and one’s ingroups along other identity dimensions.
Teaching Listening Comprehension of Science e-Texts for Students With Moderate Intellectual Disability
Authors: Wood Leah , Browder Diane M. , Spooner Fred
Published: October 2019

This study examined the effects of a treatment package that combined technology-based supports and systematic instruction on the comprehension skills of elementary-aged students with moderate intellectual disability. Researchers used a multiple probe across participants design. Specifically, researchers examined the effects of constant time delay and a system of least prompts on both generating and answering questions about science electronic texts (e-texts) for student participants. A functional relation was demonstrated for both generating questions using an iPad and answering comprehension questions. All three students demonstrated an ability to correctly answer questions about an e-text read aloud via text-to-speech by either saying an answer from memory or independently searching the e-text and replaying the target text to find the correct answer. A functional relation also was demonstrated between constant time delay instruction and the points earned accurately generating questions using an iPad. Skills transferred to a third-grade general education classroom environment.
Relational Factors Influencing Parents’ Engagement in Special Education for High School Youth With Emotional/Behavioral Problems
Authors: Carlson Ryan G. , Hock Robert , George Melissa , Kumpiene Gerda , Yell Mitch , McCartney Esther D. , Riddle David , Weist Mark D.
Published: October 2019

This study examined the relational factors influencing school engagement for parents of high school youth with emotional/behavioral disorders. Fourteen parents of high school students (12 mothers, two fathers) who received special education services participated in semistructured interviews. Formal qualitative analyses of audiotaped phone interviews revealed some positive and some negative experiences by parents, the importance of coparenting to increase supportiveness to their child (and dimensions of effective coparenting), and recommendations from them for improving family engagement processes. In general, parents appreciated and recommended proactive and positive communication and collaboration with school staff emphasizing student strengths, being genuinely and meaningfully involved in the Individualized Education Program (IEP) process, with adequate time allowed for this involvement, and for staff to be organized and engaged in working with them. Findings are discussed in relation to ideas for practice and policy enhancement, and future research directions.
A qualitative investigation into the impact of domestic abuse on women’s desistance
Authors: Barr Úna , Christian Natalie
Published: October 2019

While criminological literature, criminal justice practice, and to a lesser extent, state policy have acknowledged a link between women’s criminalisation and gendered violence (MoJ, 2018; Österman, 2018; Prison Reform Trust, 2017; Roberts, 2015), there has been much less acknowledgement of the role of historical and contemporaneous experiences of violence in the desistance scripts of criminalised women. Combining findings from two research projects exploring gender and desistance, this article argues that (i) criminalised women’s experiences of gendered violence are such that any exploration of gender and desistance which does not acknowledge this is incomplete, (ii) coercion and control can inform women’s entry into the criminal justice system, (iii) expressions of agency and resistance in abusive interpersonal relationships can also inform women’s offending, yet (iv) women’s experiences of desistance from crime can mask the harm they face in coercive, controlling, and violent relationships. Thus, the article argues for a reframing of desistance from crime as desistance from harm both theoretically and in practice, and considers what this might entail.
Equitable persistent coverage of non-convex environments with graph-based planning
Authors: Palacios-Gasós José Manuel , Tardioli Danilo , Montijano Eduardo , Sagüés Carlos
Published: October 2019

In this article, we tackle the problem of persistently covering a complex non-convex environment with a team of robots. We consider scenarios where the coverage quality of the environment deteriorates with time, requiring every point to be constantly revisited. As a first step, our solution finds a partition of the environment where the amount of work for each robot, weighted by the importance of each point, is equal. This is achieved using a power diagram and finding an equitable partition through a provably correct distributed control law on the power weights. Compared with other existing partitioning methods, our solution considers a continuous environment formulation with non-convex obstacles. In the second step, each robot computes a graph that gathers sweep-like paths and covers its entire partition. At each planning time, the coverage error at the graph vertices is assigned as weights of the corresponding edges. Then, our solution is capable of efficiently finding the optimal open coverage path through the graph with respect to the coverage error per distance traversed. Simulation and experimental results are presented to support our proposal.
‘INSIGHT-PRECISION’: a new, mini-invasive technique for the surgical treatment of carpal tunnel syndrome
Authors: Carmo José Dinis
Published: October 2019

Objective

To describe a new mini-invasive surgical technique for carpal tunnel release and to present clinical findings associated with using this technique.

Methods

Patients with idiopathic carpal tunnel syndrome without prior surgical treatment, who underwent a new minimally-invasive surgical technique using a specific surgical tool-kit developed by the author, were included. Prospective data were collected, including preoperative electrodiagnostic testing. The subjective condition of all patients was evaluated pre- and postoperatively with a five-level Likert-type scale (LS) and muscular strength was tested using a JAMAR dynamometer and pinch gauge.

Results

A total of 116 patients (157 hands/cases) underwent surgery performed by the author, and were followed for a mean of 40 months (range, 6 months–7 years). Of these, preoperative electrodiagnostic testing was performed in 112 patients (96.6%). No significant complications were reported. By three months, patients reported that they were satisfied or very satisfied in 147/149 cases (98.7%; LS grade I and II). Strength recovery at three months, based on the average of four measures, was 99.17% (range, 97.43–100.97%).

Conclusions

The described technique is minimally invasive, safe and simple to perform, and provides good results.
Observation of the clinical efficacy of dexmedetomidine in flexible bronchoscopy under general anesthesia: clinical case experience exchange
Authors: Li Hongtu , Zhang Na , Zhang Ke , Wei Yanhua
Published: October 2019

Object

To investigate the clinical efficacy and safety of dexmedetomidine in flexible bronchoscopy under general anesthesia.

Methods

A total of 114 patients were randomly divided into intervention group A and control group B. Group A received dexmedetomidine, fentanyl, and propofol as anesthesia, while Group B received fentanyl and propofol only. Changes in heart rate, mean arterial pressure, pulse oxygen saturation, stress indices (blood cortisol, adrenaline, and norepinephrine levels), incidence of adverse events, anesthesia dose, duration of procedure, and recovery time were compared between the groups at specific time points T0, T1, and T2 during bronchoscopy.

Results

There was no statistical difference between the groups at T0. At T1 and T2, pulse oxygen saturation, mean arterial pressure, heart rate, and stress indices in group A were significantly more favorable than those in group B. The incidence of adverse events (5.26%) in group A was significantly lower than that in group B (17.54%), and patients in group A required less propofol and had a faster recovery time than patients in group B.

Conclusion

Dexmedetomidine use in flexible bronchoscopy under general anesthesia is safe and effective and decreases the stress response in synergy with propofol to provide hemodynamic stability.
Anesthesia in a patient with Charcot-Marie-Tooth disease with pneumothorax: a case report
Authors: Kim Jae Won , Kim Goo , Kim Tae Woo , Han Woong , Maeng Jin Hyun , Jeong Chang Young , Choi Jin Ho , Park Dong Ho
Published: October 2019

A 21-year-old man underwent wedge resection for treatment of pneumothorax. This patient had been diagnosed with Charcot-Marie-Tooth disease (CMTD) and had a history of surgical treatment of scoliosis, pneumothorax, foot deformity, and arm dislocation. Additionally, the patient showed signs of muscle weakness and atrophy in the upper and lower extremities.

CMTD is genetically associated with motor and sensory neuropathy and reportedly has an association with malignant hyperthermia or a delayed muscle relaxation mechanism. In the present case, total intravenous anesthesia was performed with a combination of propofol and remifentanil, and rocuronium was administered as a neuromuscular blocking agent. Surgery was performed without delayed muscle relaxation or any other specific intraoperative adverse events.
The state project of crisis management: China’s Shantytown Redevelopment Schemes under state-led financialization
Authors: He Shenjing , Zhang Mengzhu , Wei Zongcai
Published: October 2019

Since 2008, China has introduced state-led financialization to inject low-interest, stable and long-term loans to facilitate urban redevelopment through national shantytown redevelopment schemes (SRSs). Extending critical state theories to China’s transitional economy, we consider SRSs to be a policy model of the state project (mode of policy-making) of crisis management that aims to revitalize the national economy in the wake of the global financial crisis. Essentially, this state project serves to tackle the legitimation crisis threatened by both the economic crisis and the escalating social discontent. Drawing on an empirical study of Chengdu, a regional hub in western China spearheading SRSs, this paper examines how the Chinese state at different levels interacts with the nascent financial market in the creation of a new “model” of urban redevelopment under state-led financialization. Having been exploited to manage economic and legitimation crises, this model has simultaneously become a source of “crisis of crisis-management” owing to the state’s “over-intervention”. This research contributes to a fresh understanding of the multiplicity of financialization by linking the financialization of urban built environment with the financialization of the state project, in which financial motives and practices shape the mode of policy making. The Chinese experience also presents a decentered interpretation of state-led financialization that renews our understanding of the multifaceted state and state projects, particularly the hybridized, often contradictory motivations and socio-economic outcomes of state interventions.
Outcomes After Arthroscopic Hip Labral Reconstruction: A Systematic Review and Meta-analysis
Authors: Rahl Michael D. , LaPorte Collin , Steinl Gabrielle K. , O’Connor Michaela , Lynch T. Sean , Menge Travis J.
Published: October 2019

Background:

The acetabular labrum is critical to maintenance of hip stability and has been found to play a key role in preservation of the hip fluid seal. For irreparable labral damage, arthroscopic labral reconstruction is an evolving technique that has been shown to decrease hip pain and restore function.

Purpose:

To provide a comprehensive review of current literature for arthroscopic hip labral reconstruction, with a focus on determining if outcomes differ between autograft or allograft tissue.

Study Design:

Systematic review and meta-analysis.

Methods:

PubMed and Scopus online databases were searched with the key terms “hip,”“labrum,”“reconstruction,” and “graft” in varying combinations. Procedures performed, complications, failures, and functional outcome measures were included in this analysis. The inverse variance method was used to calculate pooled estimates and 95% CIs.

Results:

Eight studies with 537 hips were included. Mean age was 37.4 years (95% CI, 34.5-40.4 years), and mean follow-up time was 29 months (95% CI, 26-33 months). Survivorship after autograft reconstruction ranged from 75.7% to 100%, as compared with 86.3% to 90.0% in the allograft cohort. In the autograft cohort, failures included 0% to 13.2% conversion to total hip arthroplasty and 0% to 11.0% revision hip arthroscopy. Failures in the allograft cohort included 0% to 12.9% total hip arthroplasty conversion, 0% to 10.0% revision arthroscopy, and 0% to 0.8% open revision surgery. Based on 6 studies, the modified Harris Hip Score improved by a mean 29.0 points after labral reconstruction ( P < .0001).

Conclusion:

Arthroscopic hip labral reconstruction results in clinically significant improvements in patient-reported outcomes. Our analysis indicates that there are no significant differences in outcomes based on graft type alone. A number of factors may determine graft choice, including patient preference, surgeon experience, operative time, morbidity, and cost. Proper patient selection based on age and severity of degenerative joint disease will also optimize outcomes after labral reconstruction.
Evaluation of Osseous Morphology of the Hip Using Zero Echo Time Magnetic Resonance Imaging
Authors: Breighner Ryan E. , Bogner Eric A. , Lee Susan C. , Koff Matthew F. , Potter Hollis G.
Published: October 2019

Background:

Femoroacetabular impingement syndrome (FAIS) is a common disorder of the hip resulting in groin pain and ultimately osteoarthritis. Radiologic assessment of FAI morphologies, which may present with overlapping radiologic features of hip dysplasia, often requires the use of computed tomography (CT) for evaluation of osseous abnormality, owing to the difficulty of direct visualization of cortical and subchondral bone with conventional magnetic resonance imaging (MRI). The use of a zero echo time (ZTE) MRI pulse sequence may obviate the need for CT by rendering bone directly from MRI.

Purpose/Hypothesis:

The purpose was to explore the application of ZTE MRI to the assessment of osseous FAI and dysplasia morphologies of the hip. It was hypothesized that angular measurements from ZTE images would show significant agreement with measurements obtained from CT images.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

Thirty-eight hips from 23 patients were imaged with ZTE MRI and CT. Clinically relevant angular measurements of hip morphology were made in both modalities and compared to assess agreement. Measurements included coronal and sagittal center-edge angles, femoral neck-shaft angle, acetabular version (at 1-, 2-, and 3-o’clock positions), Tönnis angle, alpha angle, and modified-beta angle. Interrater agreement was assessed for a subset of 10 hips by 2 raters. Intermodal agreement was assessed on the complete cohort and a single rater.

Results:

Interrater agreement was demonstrated in both CT and ZTE, with intraclass correlation coefficient values ranging from 0.636 to 0.990 for ZTE and 0.747 to 0.983 for CT, indicating “good” to “excellent” agreement. Intermodal agreement was also shown to be significant, with intraclass correlation coefficients ranging from 0.618 to 0.904.

Conclusion:

Significant agreement of angular measurements for hip morphology exists between ZTE MRI and CT imaging. ZTE MRI may be an effective method to quantitatively evaluate osseous hip morphology.
Single-Leg Squat Performance and Its Relationship to Extensor Mechanism Strength After Anterior Cruciate Ligament Reconstruction
Authors: Batty Lachlan M. , Feller Julian A. , Hartwig Taylor , Devitt Brian M. , Webster Kate E.
Published: October 2019

Background:

Performance in strength and functional testing is important when considering return to sport after anterior cruciate ligament (ACL) reconstruction. Both knee extensor strength and the single-leg squat (SLS) have been used in this context.

Purpose:

To evaluate the relationship between knee extensor strength and SLS performance after primary ACL reconstruction.

Study Design:

Cohort study (Diagnosis); Level of evidence, 3.

Methods:

A prospective cohort of 100 patients was assessed 6 and 12 months after primary ACL reconstruction with a hamstring tendon autograft. Knee extensor peak torque was measured. Three sequential SLSs were performed, and the maximum flexion angle identified from frame-by-frame video analysis was used as the measure of squat performance. A limb symmetry index (LSI) was calculated and satisfactory performance defined as ≥90%.

Results:

Extensor mechanism strength deficits were seen in 75% of patients at 6 months and 57% at 12 months postoperatively. Mean extensor mechanism strength showed a large improvement between 6 and 12 months (123.6 vs 147.8 N·m, respectively; P < .001; Cohen d = 1.10), and while there was also a statistically significant improvement in the mean maximum flexion angle, the change was small (66.1° vs 68.1°, respectively; P = .011; Cohen d = 0.26). There was a weak positive correlation between knee extensor strength and the SLS maximum flexion angle at 6 months ( r = 0.342; P < .001) and 12 months ( r = 0.245; P = .014). An SLS LSI <90% was 80% specific and 35% sensitive for extensor mechanism weakness at 6 months and 79% specific and 18% sensitive at 12 months.

Conclusion:

Extensor mechanism strength deficits are common after ACL reconstruction but reduce between 6 and 12 months. The SLS maximum flexion angle has a weak linear relationship to knee extensor strength. SLS performance has high specificity but low sensitivity in identifying extensor mechanism strength deficits. The SLS maximum flexion angle is therefore a suboptimal surrogate test to identify extensor mechanism strength deficits as diagnosed by isokinetic dynamometric testing. However, unsatisfactory SLS performance indicates a very high chance of underlying extensor mechanism weakness.
The Association Between Tibial Slope and Revision Anterior Cruciate Ligament Reconstruction in Patients ≤21 Years Old: A Matched Case-Control Study Including 317 Revisions
Authors: Cooper Joseph D. , Wang Wei , Prentice Heather A. , Funahashi Tadashi T. , Maletis Gregory B.
Published: October 2019

Background:

There is evidence that tibial slope may play a role in revision risk after anterior cruciate ligament reconstruction (ACLR); however, prior studies are inconsistent.

Purpose:

To determine (1) whether there is a difference in lateral tibial posterior slope (LTPS) or medial tibial posterior slope (MTPS) between patients undergoing revised ACLR and those not requiring revision and (2) whether the medial-to-lateral slope difference is different between these 2 groups.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

We conducted a matched case-control study (2006-2015). Cases were patients aged ≤21 years who underwent revision surgery after primary unilateral ACLR; controls were patients aged ≤21 years without revision who were identified from the same source population. Controls were matched to cases by age, sex, body mass index, race, graft type, femoral fixation device, and post-ACLR follow-up time. Tibial slope measurements were made by a single blinded reviewer using magnetic resonance imaging. The Wilcoxon signed rank test and McNemar test were used for continuous and categorical variables, respectively.

Results:

No difference was observed between revised and nonrevised ACLR groups for LTPS (median: 6° vs 6°, P = .973) or MTPS (median: 4° vs 5°, P = .281). Furthermore, no difference was found for medial-to-lateral slope difference (median: −1 vs −1, P = .289). A greater proportion of patients with revised ACLR had an LTPS ≥12° (7.6% vs 3.8%) and ≥13° (4.7% vs 1.3%); however, this was not statistically significant after accounting for multiple testing.

Conclusion:

We failed to observe an association between revision ACLR surgery and LTPS, MTPS, or medial-to-lateral slope difference. However, there was a greater proportion of patients in the revision ACLR group with an LTPS ≥12°, suggesting that a minority of patients who have more extreme values of LTPS have a higher revision risk after primary ACLR. A future cohort study evaluating the angle that best differentiates patients at highest risk for revision is needed.
Does Injection of Hyaluronic Acid Protect Against Early Cartilage Injury Seen After Marathon Running? A Randomized Controlled Trial Utilizing High-Field Magnetic Resonance Imaging
Authors: Nathani Amit , Gold Garry E. , Monu Uchechukwuka , Hargreaves Brian , Finlay Andrea K. , Rubin Elka B. , Safran Marc R.
Published: October 2019

Background:

Previous studies have shown that runners demonstrate elevated T2 and T1ρ values on magnetic resonance imaging (MRI) after running a marathon, with the greatest changes in the patellofemoral and medial compartment, which can persist after 3 months of reduced activity. Additionally, marathon running has been shown to increase serum inflammatory markers. Hyaluronic acid (HA) purportedly improves viscoelasticity of synovial fluid, serving as a lubricant while also having chondroprotective and anti-inflammatory effects.

Purpose/Hypothesis:

The purpose was to investigate whether intra-articular HA injection can protect articular cartilage from injury attributed to marathon running. The hypothesis was that the addition of intra-articular HA 1 week before running a marathon would reduce the magnitude of early cartilage breakdown measured by MRI.

Study Design:

Randomized controlled trial; Level of evidence, 2.

Methods:

After institutional review board approval, 20 runners were randomized into receiving an intra-articular injection of HA or normal saline (NS) 1 week before running a marathon. Exclusionary criteria included any prior knee injury or surgery and having run >3 prior marathons. Baseline 3-T knee MRI was obtained within 48 hours before the marathon (approximately 5 days after injection). Follow-up 3-T MRI scans of the same knee were obtained 48 to 72 hours and 3 months after the marathon. The T2 and T1ρ relaxation times of articular cartilage were measured in 8 locations—the medial and lateral compartments (including 2 areas of each femoral condyle) and the patellofemoral joint. The statistical analysis compared changes in T2 and T1ρ relaxation times (ms) from baseline to immediate and 3-month postmarathon scans between the HA and NS groups with repeated measures analysis of variance.

Results:

Fifteen runners completed the study: 6 women and 2 men in the HA group (mean age, 31 years; range, 23-50 years) and 6 women and 1 man in the NS group (mean age, 27 years; range, 20-49 years). There were no gross morphologic MRI changes after running the marathon. Postmarathon studies revealed no statistically significant changes between the HA and NS groups in all articular cartilage areas of the knee on both T2 and T1ρ relaxation times.

Conclusion:

Increased T2 and T1ρ relaxation times have been observed in marathon runners, suggesting early cartilage injury. The addition of intra-articular HA did not significantly affect relaxation times in all areas of the knee when compared with an NS control.
Integrating Investment and Annual Planning
Authors: Hahnel Robin , Kerkhoff Allison
Published: October 2019

This article illustrates (1) how to determine an efficient division of output between aggregate consumption and aggregate investment in a way that is democratic and participatory, and (2) how annual and investment planning can be integrated to improve outcomes as more accurate information becomes available. The article is of general relevance to the literature on economic planning, but is of particular interest to a post-capitalist “model” known as “participatory economics.”
What Are High-Leverage Practices for Special Education Teachers and Why Are They Important?
Authors: McLeskey James , Billingsley Bonnie , Brownell Mary T. , Maheady Lawrence , Lewis Timothy J.
Published: October 2019

Improving educational outcomes for students with disabilities and others who struggle in school largely depends on teachers who can deliver effective instruction. Although many effective practices have been identified to address the academic and behavioral needs of students who struggle in school, including those with disabilities, these practices are not used extensively in classrooms. This article provides a rationale for and description of major changes that are occurring in teacher preparation programs that are designed to improve the practice of beginning teachers. This is followed by a description of a set of high-leverage practices that was recently approved by the Council for Exceptional Children. These practices represent an initial attempt to delineate a core curriculum for special education teacher preparation to support the changes that are occurring in teacher education.
High-Definition Liposculpture in Males Using Power-Assisted Liposuction and Local Anesthesia
Authors: Boeni Roland
Published: October 2019

In high-definition liposculpture, the body is being shaped in a manner that it creates an athletic appearance and defined, contoured look. Typical areas in the male patient include arms, pectoralis, the area over the serratus muscle, lower back, as well as lateral and medial abdomen. This is sometimes combined with fat grafting to areas over the deltoid muscle and/or pectorals. High-definition liposculpture poses a new challenge to local anesthesia using lidocaine alone. Sufficient analgesia has to be achieved in multiple areas, without reaching systemic toxic levels of lidocaine. To reduce the risk of systemic side effects, we added prilocaine to the tumescent solution. Prilocaine differs from lidocaine in its metabolizing pathway, and combining both anesthetics therefore allows for higher tumescent volumes. In a prospective study, 48 male patients underwent high-definition liposculpture. The mean injected volume was 9.4 L. There were no side effects resulting from the high volumes of tumescent solution. Minor complications included seroma (2); 3 patients required touch-up. To conclude, a combination of lidocaine and prilocaine enables treatment of the entire torso and arms in a single session. Potential systemic effects of each anesthetic, lidocaine and prilocaine, need to be known to the user.
Fatigue failure analysis of ceramic tools in intermittent cutting harden steel based on experiments and finite element method
Authors: Ni Xiuying , Zhao Jun , Gong Feng , Li Gang
Published: October 2019

The major concern of this article is the fatigue failure mechanisms of ceramic cutting tools with the help of intermittent turning experiment and simulation. Finite element simulation was adopted to analyze the spatial and temporal distribution of the stress on the cutting tools. The crack initiation and expansion life in the different positions was researched based on the fatigue crack model. The experiment results showed that the fracture area of flank face reduced with the increase in feed rates, while the fracture area and damage depth of rake face both increased. Through the simulation of fatigue crack, it could be inferred that fatigue fractures were caused by coalescence of cracks. When the feed rate was greater than or equal to 0.2 mm, tool failure was mainly manifested as fatigue fracture of the rake face. And the results of fatigue crack propagation simulation well predicted the cutting tool life. A novel research method for tool fatigue failure was provided.