bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of elastomeric composites as alternative materials for marine applications: A compendious review on their properties and opportunities
Authors: Aravind D , Senthilkumar K , Rajini N , Muthu Kumar T Senthil , Chandrasekar M , Ismail Sikiru O , Yeetsorn Rungsima , Parameswaranpillai Jyotishkumar , Siengchin Suchart , Indira Devi MP
Published: May 2022

The term elastomer is a curtailment of two words, which are elastic and polymers. Accordingly, elastomers are polymer materials with elasticity. The significant challenges hindering the development of materials for naval applications, similar to other engineering sectors, include achieving a competitive light elastomeric structure. Marine structures are susceptible to various damage responses due to various loads throughout their service life. Being flexible, elastomer has a low modulus of elasticity, exhibits higher values of failure strain and yield strength. In these regards, elastomers are attractive materials for applications that require elasticity because they offer substantial advantages compared to traditional materials. However, the low fire resistance of these elastomeric materials jeopardizes their use in some critical applications. As a result, elastomeric blends and composites containing flame retardant (FR) additives are commonly used. On the other hand, elastomers possess (i) high strength-to-weight ratio, (ii) excellent impact properties, (iii) low infrared, magnetic, and radar signatures, (iv) excellent durability, and (v) high resilience to extreme loads. Hence, the scope of this study focuses on review and awareness regarding the feasibility of marine applications of elastomers/elastomeric composites, their current scientific and technological drawbacks, and future outlooks or prospects to support several applications in the marine industry.
Fast Approximate Quantification of Endovascular Stent Graft Displacement Forces in the Bovine Aortic Arch Variant
Authors: Sturla Francesco , Caimi Alessandro , Romarowski Rodrigo M. , Nano Giovanni , Glauber Mattia , Redaelli Alberto , Votta Emiliano , Marrocco-Trischitta Massimiliano M.
Published: May 2022

Purpose:

Displacement forces ( DFs) identify hostile landing zones for stent graft deployment in thoracic endovascular aortic repair (TEVAR). However, their use in TEVAR planning is hampered by the need for time-expensive computational fluid dynamics (CFD). We propose a novel fast-approximate computation of DFs merely exploiting aortic arch anatomy, as derived from the computed tomography (CT) and a measure of central aortic pressure.

Materials and Methods:

We tested the fast-approximate approach against CFD gold-standard in 34 subjects with the “bovine” aortic arch variant. For each dataset, a 3-dimensional (3D) model of the aortic arch lumen was reconstructed from computed tomography angiography and CFD then employed to compute DFs within the aortic proximal landing zones. To quantify fast-approximate DFs, the wall shear stress contribution to the DF was neglected and blood pressure space-distribution was averaged on the entire aortic wall to reliably approximate the patient-specific central blood pressure. Also, DF values were normalized on the corresponding proximal landing zone area to obtain the equivalent surface traction ( EST).

Results:

Fast-approximate approach consistently reflected (r2=0.99, p<0.0001) the DF pattern obtained by CFD, with a −1.1% and 0.7° bias in DFs magnitude and orientation, respectively. The normalized EST progressively increased (p<0.0001) from zone 0 to zone 3 regardless of the type of arch, with proximal landing zone 3 showing significantly greater forces than zone 2 (p<0.0001). Upon DF normalization to the corresponding aortic surface, fast-approximate EST was decoupled in blood pressure and a dimensionless shape vector (S) reflecting aortic arch morphology. S showed a zone-specific pattern of orientation and proved a valid biomechanical blueprint of DF impact on the thoracic aortic wall.

Conclusion:

Requiring only a few seconds and quantifying clinically relevant biomechanical parameters of proximal landing zones for arch TEVAR, our method suits the real preoperative decision-making process. It paves the way toward analyzing large population of patients and hence to define threshold values for a future patient-specific preoperative TEVAR planning.
Do Fans Impact Sports Outcomes? A COVID-19 Natural Experiment
Authors: Cross Jeffrey , Uhrig Richard
Published: May 2022

This paper studies the effect of fan attendance on home field advantage in top European soccer leagues. We exploit exogenous variation in the level of fan attendance driven by COVID-19 mitigation policies and find that the home field advantage, as measured by home minus away (expected) goals, is reduced by more than 50% across the English Premier League, German Bundesliga, Italian Serie A, and Spanish La Liga. This leads to a decrease in probability for a home win, indicating that these goals are pivotal with respect to match outcomes.
Women as Embodied Infrastructures: Self-Led Organisations Sustaining the Lives of Female Victims of Conflict-Related Sexual Violence in Colombia
Authors: Nieto-Valdivieso Yoana Fernanda
Published: May 2022

The article looks at women self-led organisations as embodied infrastructures supporting the lives of victim-survivors of conflict-related sexual violence in Colombia. Focusing on three elements that form the concept of women as embodied infrastructures namely, i) the roles women play as mentors and role models for other women, ii) women's work in women's services, networks, and organisations, iii) radical care, I argue that women as embodied infrastructures provide important listening and learning safe-spaces where victim-survivors can regain self-love, a political understanding of their victimisation, access peer support, gain citizenship skills, and begin to heal. By enabling victims-survivors to become agents in the process of rebuilding their lives, their livelihoods, and their wider ecologies the work of these organisations promotes gender-transformative change and is central to peacebuilding and transitional justice processes.
A distributed energy-efficient opportunistic routing accompanied by timeslot allocation in wireless sensor networks
Authors: Ri Man Gun , Han Ye Song , Pak Jin
Published: May 2022

Sensed data can be forwarded only in one direction to the base station in one-dimensional queue wireless sensor networks different from mesh structure, so the network lifetime will be shortened if some continuous neighboring nodes have run out of their energy. So designing routing protocols for balancing energy consumption is a challenging problem. However, traditional and existing opportunistic routing protocols for one-dimensional queue wireless sensor network proposed so far have not yet addressed this problem to prolong the network lifetime by introducing sleep mode. In this article, we propose a distributed energy-efficient opportunistic routing algorithm accompanied by timeslot allocation by using specific network topology of one-dimensional queue wireless sensor network. In our new algorithm, clustering and routing tree construction is performed while introducing the optimal relay transmission distance achieved by using opportunistic routing principle, and at the same time, interference-free wake up time is scheduled, which may optimize energy consumption and decrease the number of various control messages as possible to prolong the network lifetime. Furthermore, this improves energy efficiency by introducing the operation mode giving up cluster head role. Simulation results show that the proposed protocol can significantly improve the network performance such as energy consumption and network connectivity, when compared with other existing protocols.
Characterizing Unusual Spatial Clusters of Male Mental Health Emergencies Occurring During the First National COVID-19 “Lockdown” in the East Midlands Region, UK: A Geospatial Analysis of Ambulance 999 Data
Authors: Moore Harriet Elizabeth , Hill Bartholomew , Tanser Frank , Siriwardena Aloysius Niroshan , Gussy Mark , Cutts Morgan , Spaight Robert
Published: May 2022

The widespread psychological effects of contagion mitigation measures associated with the novel coronavirus disease 2019 (COVID-19) are well known. Phases of “lockdown” have increased levels of anxiety and depression globally. Most research uses methods such as self-reporting that highlight the greater impact of the pandemic on the mental health of females. Emergency medical data from ambulance services may be a better reflection of male mental health. We use ambulance data to identify unusual clusters of high rates of male mental health emergencies occurring in the East Midlands of the United Kingdom during the first national “lockdown” and to explore factors that may explain clusters. Analysis of more than 5,000 cases of male mental health emergencies revealed 19 unusual spatial clusters. Binary logistic regression analysis (χ2 = 787.22, df = 20, p ≤ .001) identified 16 factors that explained clusters, including proximity to “healthy” features of the physical landscape, urban and rural dynamics, and socioeconomic condition. Our findings suggest that the factors underlying vulnerability of males to severe mental health conditions during “lockdown” vary within and between rural and urban spaces, and that the wider “hinterland” surrounding clusters influences the social and physical access of males to services that facilitate mental health support. Limitations on social engagement to mitigate effects of the pandemic are likely to continue. Our approach could inform delivery of emergency services and the development of community-level services to support vulnerable males during periods of social isolation.
New concept carrier of front-end module with structural topology optimization for automotive
Authors: Lee Kibum , Park Soojin , Lee Younghyoung , Kim Jinho , Kim Soo-Hyun
Published: May 2022

The vehicle front-end module (FEM) is an integrated system in which major modules are assembled in the front of the vehicle. Among the FEM components, a carrier occupies the largest volume and weight. In recent years, the requirements of a carrier are increasing due to the diversification of vehicle size, enlargement of headlight, and so on. So, recent requirements are difficult to satisfy with the existing design. Therefore, this study was attempted to solve the current problems by applying only plastic, not the existing hybrid type, to the most important Member-radiator Support Upper (MRSU) of the carrier. As a process, topology optimization was performed using Altair’s Optistruct, thereby implementing a new concept of MRSU. In addition, the strength analysis was conducted using ABAQUS of Simulia. An initial model and an optimized model were compared and verified to determine the validity of optimization. After that, a prototype of carrier was manufactured and the final verification was conducted through HLR test. As a result, the strength and weight of the carrier were improved by about 24% and 15% respectively. In addition, the waste-generating process was improved, resulting in a development time reduction of approximately 32%.
Fascination, nostalgia, and knowledge desire in digital memory culture: Emotions and mood work in retrospective Facebook groups
Authors: Ekelund Robin
Published: May 2022

This article explores how emotions are practised within retrospective Facebook groups and how these practices are shaped by the logics of the interface. Theoretical inspiration is drawn from Ahmed’s discussions on emotions and mood work and the study is based on netnographic fieldwork involving six retrospective Facebook groups. Overall, a positive emotional relationship with the past is practised and the analysis illustrates that three interrelated mood works are found in the groups; fascination, nostalgia and knowledge desire. The analysis of these indicate that Facebook’s interface directs the members towards fragmented interactions which produces a memory culture that is more focused on brief and general, rather than elaborate and specific, accounts of the past. I conclude by discussing how the emotional practices within the retrospective Facebook groups creates a double-edged sword; at the same time as they offer a sense of positive emotional belonging for likeminded members, they also risk producing simplified notions of the past that feeds into retrotopian tendencies of the present.
Linking customized logistics service in online retailing with E-satisfaction and E-loyalty
Authors: Hu Mingyao , Chaudhry Peggy E , Chaudhry Sohail S
Published: May 2022

Online retailers are providing customized logistics service to meet heterogeneous customer demand. However, the value of customized logistics service is not clear. We study conceptually and empirically how customized logistics service influences online customer post-purchase behavior, specifically e-satisfaction and e-loyalty. Primary data on customized logistics service were collected from an online field study involving direct observation. Secondary data on e-satisfaction and e-loyalty were collected from Bizrate.com. We used hierarchical multiple regression analyses and constrained nonlinear regression for empirical analysis. The results indicate that customized logistics service contributes significantly to e-satisfaction and, in turn, to e-loyalty. Furthermore, shipping rates significantly moderate the indirect effect of customized logistics service on e-loyalty through e-satisfaction. This research contributes to the understanding of the nature and consequences of customized logistics service in online retailing. Our findings underscore the effect of customized logistics service on e-satisfaction and e-loyalty, and the critical moderation effects of shipping rate on these relationships. Results from this study hold implications for the way online service operations managers employ logistics service strategy.
How Do Populists Visually Represent ‘The People’? A Systematic Comparative Visual Content Analysis of Donald Trump and Bernie Sanders’ Instagram Accounts
Authors: Moffitt Benjamin
Published: May 2022

How do populists visually represent “the people”? While the literature on populism has tended to focus on text- and language-based documents, such as speeches, policies, and party documents to consider how populists characterize “the people,” in this article I undertake a systematic visual content analysis to consider how populist leaders on either side of the ideological spectrum visually represent “the people” in images from their official Instagram accounts ( N = 432). Comparing the cases of Donald Trump on the populist right and Bernie Sanders on the populist left, I code for the majority gender, race, and age of “the people” in each image, and supplement this with a discussion of the depictions of these categories. I find that Trump’s images of “the people” are significantly more homogenous across all categories—specifically more white, more masculine, and with less young people—than Sanders’, and situate these findings in the context of the literature on the differences between left and right populism. This article contributes to the study of populist communication by highlighting the role of images in representing “the people”; analyzing how left and right populists do this differently; and developing a method for measuring the demographic characteristics of “the people” in populists’ images that can be used in future studies. In doing so, it seeks to push the literature forward by highlighting that images are not something “extra” to be studied in populist communication, but rather are a central battleground for the construction of populist identities.
Sanjana’s ethical dilemma in disruptive technologies
Authors: Fernando Ameeta
Published: May 2022

Ethics is an often-debated topic in technology circles. Ethical implementation of information systems is an important aspect of the curriculum in management institutions. Since students in business schools hail from different academic streams, they may come in with or without in-depth technical knowledge on the software/information systems that run the business. It becomes the duty of academia in this context, to educate them on the ethical challenges that managers would face in implementing disruptive technologies in their organizations. The onus on creating managers who can make humans out of machines (and not vice versa) is on the faculty in these management institutes. One of the most effective ways to achieve this objective is through the case study tool. The protagonist in this case, Sanjana is faced with a series of ethical issues in her new workspace which has recently undergone a digital transformation. The primary objective of this case study is to enable management students (who may not have in-depth technological knowledge and/or expertise) to: 1. Identify limitations of technological components (especially data sciences, AI, ML, and DL systems) in business given the growing levels of implementations of these systems in all business domains. 2. Think out of the box and provide innovative solutions to technology-related ethical challenges in such a manner that human-aided computer systems function within business peripherals to ensure a secure, unbiased environment to all stakeholders.
Caregiving for Interstage Infants: A Continuous Process of Compromise During the Pandemic
Authors: Imperial-Perez Flerida , Pike Nancy A. , Doering Lynn V. , Eastwood Jo-Ann , Heilemann MarySue V.
Published: May 2022

Background: Infants born with single ventricle heart disease require in-home medicalized care during the interstage period (time between the first and second staged heart surgery). These caregivers rely on extended family, friends, and hired caretakers to provide respite time. However, the coronavirus pandemic removed these families’ options due to stay-at-home and social distancing directives. We explored the caregivers’ experiences during the interstage period, including impacts on their lifestyle, as they managed their infants’ critical needs during the coronavirus disease 2019 pandemic. Method: In-person or telephonic interviews of 14 caregivers interviewed once or twice were conducted between November 2019 and July 2020. Constructivist Grounded Theory methodology guided both data collection and analysis for the inductive and abductive exploration of caregivers’ experiences. Results: Data analysis led to the development of 2 concepts: Accepting and adapting to a restrictive home environment and Reconciling what is and what is yet to come. Refinement of the relationship between the 2 concepts led to the development of a theory grounded in the words and experiences of the participants called: A Continuous Process of Compromise. Conclusions: Our findings increase understanding of caregivers’ experiences related to psychosocial and lifestyle impacts and the need for additional support during the interstage period.
Delays in ACL Reconstruction are Associated with Higher Rates of Meniscus and Chondral Pathology in Skeletally Immature Patients
Authors: Pennock AT , Milewski MD , Hutchinson LE , Miller PE ,   PLUTO Study Group Kocher MS
Published: May 2022

Background:

ACL reconstruction timing remains controversial with some studies favoring early reconstruction within 60 to 90 days of injury to lessen the probability of chondral and meniscus pathology.

Hypothesis/Purpose:

To prospectively evaluate skeletally immature patients with ACL tears to assess the correlation between meniscus and chondral pathology and delays in surgical treatment, and to determine if surgical delays lead to higher rates of meniscus debridement and a higher need for cartilage treatment.

Methods:

A consecutive series of skeletally immature patients diagnosed with ACL tears between 2016 and 2020 from 10 geographically diverse institutions were enrolled. Univariable and multivariable logistic regression analysis was performed to determine the association between time from injury to surgery and the likelihood of meniscal or chondral injury.

Results:

Analysis included 747 patients, and 56.6% had a meniscus tear. Tears were more likely to occur in older patients (chronologic age 12.6 versus 12.0; p≤0.001). Patients with a bone age greater than 13 years were 2 times more likely to have a meniscus tear (OR=2.0; p≤0.001). No association was detected between continuous time to surgery and likelihood of a meniscus tear. However, patients who had surgery greater than 60 days from injury were 1.5 times more likely to have a meniscal tear (OR=1.54; p=0.006). The lateral and medial meniscus were repaired 68% and 90% of the time, respectively. There was no association between time from injury to surgery and the likelihood of repair. Sixty-five chondral injuries in 48 patients were identified. Patients who had surgery more than 90 days from injury were 3 times more likely to have a chondral injury (OR=3.3; p≤;0.001). Furthermore, patients with a bone age greater than 13 years had 7 times the odds of chondral injury (OR=6.8; p=0.002) compared to younger patients. Nineteen of 48 patients (40%) with chondral injury required treatment, but there was no association between time from injury to surgery and the need for treatment (p=0.55).

Conclusion:

A synergistic effect between patient age and delay in surgery was observed such that older patients and those with longer delays to surgery were more likely to have meniscus and chondral pathology at the time of ACL reconstruction. This data suggests that older adolescent patients may benefit from earlier surgical intervention, but it is unclear whether earlier surgery will alter the rates of long-term osteoarthritis. [Figure: see text][Figure: see text]
Incidence and Risk Factors of Heterotopic Ossification in a Matched Cohort Pediatric Population Undergoing Hip Arthroscopy
Authors: Feroe Aliya G. , Flaugh Rachel A. , Hassan Mahad M. , Maier Stephen P. , Cook Danielle L. , Yen Yi Meng , Kocher Mininder S.
Published: May 2022

Background:

The development of heterotopic ossification (HO) is a known complication after hip arthroscopy in adults and has been associated with male sex, older age, larger CAM resection, and obesity. However, the incidence after hip arthroscopy in the pediatric population is not well-documented.

Hypothesis/Purpose:

The purpose of this retrospective case-control study was to determine the incidence and risk factors for the development of HO in pediatric patients following hip arthroscopy over a ten-year period.

Methods:

Internal clinical and surgical records from a single pediatric institution were queried to identify all patients under the age of 21 years who underwent hip arthroscopy between 2008 and 2018. For analyses, the 27 cases that developed HO were matched 1:4 on age and sex with 107 controls that did not. Univariate logistic regression analysis was conducted to assess the relationship between demographic and perioperative factors on the development of HO. Multivariate logistic regression was utilized to determine what association, if any, the use of prophylactic NSAIDs (indomethacin 75 mg for three weeks) had on the development of HO when controlling for the change in alpha angle.

Results:

Twenty-seven of 693 (3.9%) hips that underwent hip arthroscopy developed HO within two years of surgery. The use of indomethacin prophylaxis (n=27) was not significantly associated with the development of HO (n=8, p=0.06), even when controlling for the change in alpha angle ( p=0.12)—nor were age, sex, and BMI percentile (Table 1). For each degree increase in the change in alpha angle, there was an 8% increase in the odds of development of HO (OR=1.08; 95% CI=1.02, 1.15; p=0.01). After controlling for preoperative alpha angle and prophylactic NSAID use, there was a 19% increase in the odds of developing HO for every degree increase in the change in alpha angle (OR=1.19; 95% CI=1.08, 1.31; p<0.001). For each degree increase in the preoperative alpha angle, the odds of developing HO increased by 11% (OR=1.11; 95% CI=1.03, 1.20; p=0.006).

Conclusion:

The incidence of HO within two years of hip arthroscopy in pediatric patients is 3.9%. Prophylactic indomethacin was not found to be protective against HO, while resection of larger CAM lesions is a risk factor for the development of HO. Although studies in the adult hip arthroscopy population have pointed to a protective role of NSAIDs in HO formation, this relationship may not be applicable to the pediatric population. [Table: see text]
Meniscal Repair Outcomes at >5 Years: A Systematic Review and Meta-Analysis
Authors: Nepple Jeffrey J. , Block Andrew M , Palumbo Noel E , Wright Rick W
Published: May 2022

Introduction:

Meniscal repair techniques (inside-out, all-inside, outside-in) continue to evolve. Assessment of meniscus repair outcomes at a minimum of 5 years postoperatively appears to best represent the true failure rates compared to 1 and 2-year timepoints. In the last decade, the literature on outcomes of meniscus repair has grown significantly.

Purpose:

To conduct a systematic review and meta-analysis to assess the rate of failure after meniscal repair at a minimum 5 years postoperatively.

Methods:

We performed a systematic review of studies reporting the outcomes of meniscal repair at a minimum of 5 years postoperatively. A standardized search strategy was utilized with the assistance of a medical librarian. Abstracts and full-text articles were reviewed by two reviewers to identify studies assessing the clinical outcome of meniscus repair, which was most uniformly assessed by reoperation. Outcomes were assessed (when reported) relative to anterior cruciate ligament (ACL) status, sex, age, and postoperative rehabilitation protocol. Pooling of data and meta-analysis with a random-effects model were performed.

Results:

A total of 28 studies of 1712 patients were included. In the last decade, 15 studies of 1168 patients have been reported, compared to 566 patients in 13 studies in the previous decade. The pooled failure rate of all devices was 22.2% (365/1712) and the failure rates of modern repairs was 17.5% (194/1128). Medial repairs were significantly more likely to fail compared to lateral repairs (26.4% [178/745] v. 13.0% [55/365], p=0.01). Failure rates varied from 16.9% for inside-out (78/501), 16.2% modern all-inside (66/396), 20.2% for outside-in (34/153), and 19.8% for open (22/109). First generation all-inside devices had a significantly higher failure rate (30.3%) compared to modern all-inside devices (16.2%) (p=0.01). There was no significant difference in failure rates between meniscal repair with concomitant ACL reconstruction (19.0%) and isolated meniscal repairs (19.6%, p=0.780). There was also no difference between post-operative rehabilitation protocols, sex, or age (all p>0.05).

Conclusions:

The outcomes of meniscal repair at a minimum 5 years postoperatively had an overall failure rate of 21.8%. Modern all-inside meniscus repair techniques appear to have improved the success rates compared to first-generation all-inside devices, and now appear similar to those of inside-out meniscus repair. Lateral repairs were significantly more likely to be successful compared to medial repairs. Finally, despite traditional teaching that ACL reconstruction improves rates of meniscus healing, across ˜700 patients, no difference in rates of healing were seen in ACL reconstruction compared to isolated meniscus repair. [Figure: see text][Figure: see text]
Osseous and Cartilaginous Trochlear Morphology in Pediatric Patients From 2 Months to 11 Years of Age: a Descriptive Analysis Based on Computed Tomography Scanning
Authors: Ayala Salvador , Rohde Matt , Gupta Anshal , Sanchez Mark , Thomas Nicholas , Tompkins Marc , Parikh Shital , Ellis Henry , Green Dan , Wilson Phil , Shea Kevin G.
Published: May 2022

Background:

The anatomy of the trochlea plays a significant role in patella stability. Surgical approaches to alter the anatomy of the trochlea and associated structures to influence patella tracking continue to evolve. Unlike the development of the pediatric hip joint which has been well studies for decades, the developmental anatomy of the trochlea and its relationship to patella stability remains poorly understood. An improved understanding of trochlear growth and development may alter both the timing and type of surgical procedures for patella stability.

Purpose:

The purpose of this study was to describe the developmental changes of the osseous and cartilage trochlear morphology in skeletally immature specimens.

Methods:

Fifty-five skeletally immature cadaveric knees between the ages of 2 months and 11 years were evaluated using 0.625mm computed tomography scans. In the axial plane, measurements included medial and lateral osseous condylar height, medial and lateral cartilaginous condylar height, osseous and cartilaginous sulcus angles, osseous and cartilaginous condylar height asymmetry, and trochlear depth.

Results:

Analysis of trochlear morphology using osseous and cartilaginous measurements of condylar height, condylar height asymmetry, and trochlear depth demonstrated an increase in the size of the medial and lateral trochlea as age increased. The osseous and cartilaginous sulcus angles decreased (became deeper) with age until around age 8 and then plateaued. This corresponded with an increase in trochlear depth that plateaued also around age 8. In contrast, medial and lateral condylar height continued to increase through age 11. Cartilaginous condylar asymmetry rose slightly with age with the lateral condyle consistently larger than the medial condyle. Osseous condylar asymmetry increased with age but flipped from a larger medial condyle to a larger lateral condyle around age 8.

Conclusions:

This cadaveric analysis demonstrated that there is an increase in the medial and lateral trochlear height as age increased by all measurements analyzed. These changes in height continue to be seen through age 11 suggesting a still developing trochlea past this age. By age 8, a plateau in sulcus angle and sulcus depth suggests more proportionate growth after this point. Access to pediatric cadaveric specimens is exceptionally rare. This study provides a unique evaluate of the developing trochlea in young children, especially those under age 7, who rarely receive advanced imaging. [Figure: see text][Figure: see text]
Predictors of Re-Operation in Adolesents Undergoing Hip Preservation Surgery for Femoroacetabular Impingement
Authors: Serbin Philip A. , Cooper Savannah , Johnson Benjamin L. , Youngman Tyler R. , Wilson Philip L. , Sucato Dan , Podeszwa David , Ellis Henry B.
Published: May 2022

Background:

Femoroacetabular Impingement(FAI) is a condition caused by repetitive motion of abnormal hip osseous anatomy that contributes to labral and chondral injury. An understanding of radiographic parameters associated with successful primary surgery has not been well established.

Hypothesis/Purpose:

The primary objective was to determine pre-operative radiographic parameters that predict reoperation for FAI and, secondarily, correlate radiographic measures and outcomes in these patients.

Methods:

A prospectively-collected institutional registry of adolescent patients (age <19 y.o.) who underwent surgery for FAI (arthroscopic/open) was reviewed. Standing AP pelvis X-rays were analyzed for alpha, lateral center edge(LCEA), Tönnis, and Sharp’s angles, and femoro-epiphyseal acetabular(FEAR) index. Patient-reported outcomes(PROs) [modified Harris Hip Score (mHHS), Hip Disability and Osteoarthritis Outcome Score(HOOS)] were analyzed. Mann-Whitney-U test was used to compare the radiographic measures of re-operation to non-reoperation patients and those who achieved MCID to those who did not. Radiographic indication of risk for re-operation was evaluated with receiver operating characteristic(ROC) analysis. Spearman’s correlation was calculated between radiographic measurements and PROs at 2-years post-op.

Results:

Eighty-seven patients underwent primary surgery (56 surgical dislocations vs 31 scopes) for FAI. The average age at time of primary operation was 16.27 years(73.6%Female). 10 underwent re-operation (11.5%) at an average of 20.6 months from primary surgery. No differences were found in demographics, activity, surgery type, labral disease, or alpha angle for re-operation vs. non-reoperation. The LCEA, FEAR Index, Sharps, and Tönnis angle were significantly different (p<0.05) (Table 1). ROC analysis indicated that LCEA<21 and FEAR index>-8.8 were predictors for increased risk of reoperation. Patients with LCEA<21°, 46% underwent a reoperation compared to those with LCEA>21° (6%). Patients with FEAR index<-8.8, 32% underwent a reoperation compared to patients>-8.8 (5%). Patients who achieved MCID (61.9%) had lower BMI, worse pre-operative PROs, and better post-operative PROs at 2-years. Alpha, Tönnis, and Sharp’s angles were positively correlated with 2+ year PROs, while LCEA was negatively correlated(p<0.05).

Conclusion:

In patients undergoing treatment for FAI, a reoperation was associated with radiographic signs of hip dysplasia, indicating that patients with a shallower acetabulum are at risk for a repeat operation. Surgeons can utilize these parameters to help in surgical decision making, better predict outcomes and to counsel patients the need for potential subsequent surgery. [Table: see text]
Visual Fatigue as a Predictor of Exercise Tolerance in Pediatric Athletes with Concussion
Authors: Bell Matthew , Thirunagari Prem Kumar , Sarva Saikaashyap , Pita Monica , Maes Luke , Harris Delaney , Streeter Leslie , Balaji Arvind , Dusenberry Brett , Mortazavi Mo
Published: May 2022

Background:

Concussion patients may manifest changes in exercise tolerance (ET). Since the visual system is affected as well, investigating the relationship between ET and vision could prove useful in developing better rehabilitation strategies.

Hypothesis/Purpose:

To explore trends between ET and visual fatigue in pediatric concussion patients.

Methods:

A Retrospective chart review of 63 pediatric concussion patients ages 12-21 was collected from 11/05/21 to 6/10/21. Each patient completed a validated symptom-related questionnaire resulting in quantitative clinical profile (CP) score (0-89) and ocular profile subtype (OPS) score (0-3) with higher scores indicating worse symptoms. The OPS score is a weighted score based off of 5 vision focused questions regarding visual symptoms and visual fatigue. Each patient was also evaluated by a physician and classified into an active rehabilitation (AR) step (Step 1-5) based on exertional testing results using heart rate to establish exertional threshold at the visit. Patients were split up into low ET level (n=10) who could not exceed HR<140bpm and high ET level (n=53) who exhibited vigorous to maximal intensities all tolerating HR>140bpm. Near point convergence (NPC) and other objective exam markers were also evaluated at each patient visit. A paired two sample t-test compared the differences in their OPS and objective clinical data.

Results:

The low ET group averaged an OPS score of 1.84, CP score of 43.20, and a physician measured average NPC of 9.96 cm, while the high ET group averaged an OPS score of 0.68, CP score of 13.87, and a physician measured NPC of 9.06 cm (Table 1). T-test for the OPS and CP score revealed statistically significant differences (p value of 4.04E-05 and 3.49E-06 respectively) while the t-test for NPC had a p-value of 0.491.

Conclusion:

Visual fatigue as endorsed by the OPS score may be a critical subjective marker in predicting ET in pediatric athletes after concussion. Those tolerating vigorous or maximal exertion generally had significantly lower OPS scores, despite similar NPC findings in this small sample. Further studies are required to confirm this trend and how it may affect exertional rehabilitation strategies. [Table: see text]
Optimal Screw Length for Osteochondritis Dissecans Fixation of the Pediatric Distal Femur: A Magnetic Resonance Imaging Comparision Study of Pediatric Epiphyseal Thickness
Authors: Sampognaro Gabriel , Massey Patrick , Nelson Bradley , Ingraffia Patrick , Simoncini Alberto , Barton R. Shane
Published: May 2022

Background:

Magnetic Resonance Imaging (MRI) allows orthopaedic surgeons to assess Osteochondritis Dissecans (OCD) of the distal femur in children. When surgical fixation is indicated, headless compression screws can be used to stabilize the fragment and allow it to heal. During screw placement it is important to make sure the screw is not too long or it may cross the physis, leading to physeal growth arrest.

Hypothesis/Purpose:

The purpose of the study was to determine the optimal screw length for osteochondritis dissecans fixation of the pediatric distal femur. A secondary objective was to compare the thickness of the epiphysis of the pediatric distal femur at different locations and screw trajectories.

Methods:

This retrospective, IRB-approved, single-institution study identified 113 pediatric patients (ages 6-17 years old) with a knee MRI from January 1, 2008 to January 1, 2020. A total of 6 measurements were obtained on each pediatric MRI by two residents. The longitudinal axis of the femur was used as a reference trajectory. Three measurements were obtained from medial femoral condyle and lateral femoral condyle, respectively. The lengths measured were from the anteromedial (AM), posteromedial (PM), and distalmedial (DM) on the medial femoral condyle to the physis. On the lateral femoral condyle, the anterolateral (AL), posterolateral (PL), and distallateral (DL) were measured. 2 sample t-testing, chi-square analysis, and Pearson’s correlation coefficient were utilized to find significant associations. Results: Of the 113 pediatric knees identified, 32 did not meet inclusion criteria, yielding 81 patients for final analysis. The average epiphyseal thickness of the bone was 25.5 mm ± 4.2 (CI 24.5 – 26.4, range 14.1 – 33.1). There was a difference in epiphyseal thickness based on screw trajectory () with the average thickness being 23.0, 22.2, 30.5, 29.3, 25.5, and 22.3 mm for the AM, AL, PM, PL, DM and DL respectively. There was a negative correlation between increasing age and epiphyseal cartilage thickness (). There was a positive correlation between increasing age and bone only epiphyseal thickness ().

Conclusion:

Our study outlines important measurements that orthopedic surgeons must be aware of when operating on OCD lesions in pediatric patients. These results can aid in determining the appropriate screw length that can be implanted into the pediatric distal femur to avoid damaging the distal femur. Our study results show that the optimal screw length to use in pediatric OCD lesion is 18mm in order to avoid physeal disturbance in the majority of pediatric patients. [Figure: see text][Figure: see text]
Mixed signals: Understanding the democratic work of narratives in pro-immigrant protests across local policy environments
Authors: Huff Alice , Cooke Abigail
Published: May 2022

The question of how to alter undemocratic environments from within is a central concern of activists and theorists interested in radical democratic change. Illuminating this issue, geographers and others have studied how immigrant rights activists make claims in hostile environments. This scholarship tends to privilege the work of organizations in national or specific metropolitan contexts. We broaden the discussion by attending to hostility in subnational immigration policy environments across the United States and by comparing the “narrative signals” that protesters send in more and less hostile environments, regardless of organizational affiliation. Results show that narratives are shaped by the environments in which they circulate. In hostile environments, however, narrative signals include a broader variety of justifications than the extant literature emphasizes. In such environments, activists justify protest both with appeals to notions of universal human rights and with more limited articulations of community concerns and specific immigrants’ attributes. We argue that while the type of narrative justifications observed in more hostile local environments can undermine democratic politics, they can also disrupt official orderings and contribute to more robust public formation around immigrant rights. Where dehumanizing policy is sharpest, they can amplify immigrant voices in the public sphere and they can draw in participants who might otherwise see themselves as disconnected from immigrant rights struggles. In shedding new light on the geography of environment-narrative dynamics, this article contributes to ongoing explorations of emplaced experiences of political work and the democratic potential of that work in hostile environments.
Predictors of Professional Fulfillment and Burnout Among Otolaryngologists During the COVID‐19 Pandemic
Authors: Karras Rachel , Matos Sophia , Sharma Arun , Crosby Dana L.
Published: May 2022

Objective

The goal of this study is to assess burnout and professional fulfillment during the initial weeks of the COVID‐19 pandemic among otolaryngology practitioners.

Study Design

Cross‐sectional survey.

Setting

International survey of otolaryngologists during a pandemic.

Methods

A cross‐sectional survey was performed from April 24 to May 8, 2020, via email and social media platforms to understand the impact of the COVID‐19 pandemic on otolaryngology practitioners in academic and private practice. The Professional Fulfillment Index was used to assess professional fulfillment and burnout. Burnout was divided into work exhaustion and interpersonal disengagement.

Results

Of 243 respondents, 202 completed the Professional Fulfillment Index portion of the survey. An average score ≥3 on the professional fulfillment section correlates with fulfillment, while an average score ≥1.33 on the burnout section correlates with burnout. The average score of professional fulfillment was 2.17, with 85.6% of respondents reporting lack of professional fulfillment. The average score on burnout was 1, with 40.1% of otolaryngologists reporting burnout. In multivariable analyses, females were found to have statistically lower professional fulfillment (beta = −2.28, P =. 010) with higher rates of work exhaustion (beta = 0.62, P <. 001), interpersonal disengagement (beta = 2.08, P =. 023), and burnout (beta = 4.49, P =. 002).

Conclusion

Early in the COVID‐19 pandemic, most participants reported a lack of professional fulfillment while just under half experienced burnout. Female gender was associated with low professional fulfillment and high work exhaustion, interpersonal disengagement, and burnout. Attention to burnout and job satisfaction during a pandemic is critical for the appropriate well‐being of otolaryngology practitioners.
Exploring the underlying molecular mechanism of liver cancer cells under hypoxia based on RNA sequencing
Authors: Zhao Xin , Liu Wenpeng , Liu Baowang , Zeng Qiang , Cui Ziqiang , Wang Yang , Cao Jinglin , Gao Qingjun , Zhao Caiyan , Dou Jian
Published: May 2022

Background

The aim of our study was to use the differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) to illustrate the underlying mechanism of hypoxia in liver cancer.

Methods

In this study, a cell model of hypoxia was established, and autophagy activity was measured with western blotting and transmission electron microscopy. The effect of hypoxia conditions on the invasion of liver cancer cell was evaluated. RNA sequencing was used to identify DEmRNAs and DEmiRNAs to explore the mechanism of hypoxia in liver cancer cells.

Results

We found that autophagy activation was triggered by hypoxia stress and hypoxia might promote liver cancer cell invasion. In addition, a total of 407 shared DEmRNAs and 57 shared DEmiRNAs were identified in both HCCLM3 hypoxia group and SMMC-7721 hypoxia group compared with control group. Furthermore, 278 DEmRNAs and 24 DEmiRNAs were identified as cancer hypoxia-specific DEmRNAs and DEmiRNAs. Finally, we obtained 19 DEmiRNAs with high degree based on the DEmiRNA-DEmRNA interaction network. Among them, hsa-miR-483-5p, hsa-miR-4739, hsa-miR-214-3p and hsa-miR-296-5p may be potential gene signatures related to liver cancer hypoxia.

Conclusions

Our study may help to understand the potential molecular mechanism of hypoxia in liver cancer.
Multiplex detection of five common respiratory pathogens from bronchoalveolar lavages using high resolution melting curve analysis
Authors: Ghorbani Jaber , Hashemi Farhad Bonakdar , Jabalameli Fereshteh , Emaneini Mohammad , Beigverdi Reza
Published: May 2022

Background

The study describes the application of the multiplex high-resolution melting curve (MHRM) assay for the simultaneous detection of five common bacterial pathogens (Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii and Escherichia coli) directly from bronchoalveolar lavage samples.

Results

Our MHRM assay successfully identified all five respiratory pathogens in less than 5 h, with five separate melting curves with specific melt peak temperatures (Tm). The different Tm were characterized by peaks of 78.1 ± 0.4 °C for S. aureus, 83.3 ± 0.1 °C for A. baumannii, 86.7 ± 0.2 °C for E. coli, 90.5 ± 0.1 °C for K. pneumoniae, 94.5 ± 0.2 °C for P. aeruginosa. The overall sensitivity and specificity of MHRM were 100% and 88.8–100%, respectively.

Conclusions

Our MHRM assay offers a simple and fast alternative to culture approach for simultaneous detection of five major bacterial lower respiratory tract infection pathogens. Utilization of this assay can help clinicians initiate prompt and appropriate antimicrobial treatment, towards reducing the morbidity and mortality of severe respiratory infections.
Perioperative outcomes of non-intubated versus intubated video-assisted thoracoscopic surgery in different thoracic procedures: a propensity score-matched analysis
Authors: Pathonsamit Chompunoot , Tantraworasin Apichat , Poopipatpab Sujaree , Laohathai Sira
Published: May 2022

Background

Non-intubated video-assisted thoracoscopic surgery (NIVATS) is increasingly performed in different types of thoracic procedures. Based on the anesthetic perspective, the outcomes of this method are limited. General anesthesia with intubation and controlled ventilation for video-assisted thoracoscopic surgery (IVATS) is a standard technique. The current study aimed to compare the pulmonary gas exchange between NIVATS and IVATS, with a focus on desaturation event.

Methods

This was a retrospective study conducted at Vajira Hospital. Data were collected from the hospital medical record database between January 9, 2019, and May 15, 2020. A propensity score-matched analysis was used to adjust the confounders by indications and contraindication between NIVATS and IVATS. The perioperative outcomes of VATS and NIVATS were compared by the regression analysis method.

Results

In total, 180 patients were included in the analysis. There were 98 and 82 patients in the NIVATS and IVATS groups, respectively. After a propensity score matching, the number of patients with similar characteristics decreased to 52 per group. None of the patients in both groups experienced desaturation. The lowest oxygen saturation of the NIVATS and IVATS groups did not significantly differ (96.5% vs. 99%, respectively; p = 0.185). The NIVATS group had a significantly higher ETCO2 peak than the IVATS group (43 vs. 36 mmHg, respectively; p < 0.001). According to the regression analysis, the NIVATS group had a significantly shorter anesthetic induction time (Mean difference (MD) = -5.135 min (95% CI = (- 8.878)- (-1.391)) and lower volume of blood loss (MD = -75.565 ml (95%CI = (- 131.08)—(- 20.65) but a higher intraoperative ETCO2 than the IVATS group (MD = 4.561 mmHg (95%CI = 1.852—7.269). Four patients in the NIVATS group required conversion to intubation due to difficulties encountered when using the surgical technique (7.7%, p = 0.041). Seven patients in the IVATS group, but none in the NIVATS group, presented with sore throat (13.5% vs. 0%, respectively; p = 0.006). Moreover, none of the patients in both groups experienced postoperative pneumonia, underwent reoperation, or died.

Conclusions

The anesthetic and surgical outcomes of NIVATS were comparable to those of IVATS.