bluuebunny/crossref_metadata_2025 huggingface dataset:
Accidental migration of a dental implant into the nasal cavity
Authors: Li Shichang , Xing Zhimin , Yu Lisheng
Published: August 2020

The accidental migration (i.e., displacement) of dental implants into the maxillary sinus is a relatively common complication in dental clinical practice. Here, we report the extremely rare nasal cavity migration of a dental implant in a 23-year-old man. Considering the superficial location of the dental implant and the absence of oronasal fistula formation, we attempted to remove the implant via endoscopy, nasal bayonet forceps, curved hooks, and suction in an ambulatory surgery setting with the patient under local anesthesia. Importantly, we were able to extract the implant with only minor complications. The patient received medication for 2 weeks and exhibited uneventful healing. Our findings may be useful for physicians and dentists who encounter similar situations in clinical practice.
Wnt/β-Catenin and Hippo Pathway Deregulation in Mammary Tumors of Humans, Dogs, and Cats
Authors: Sammarco Alessandro , Gomiero Chiara , Sacchetto Roberta , Beffagna Giorgia , Michieletto Silvia , Orvieto Enrico , Cavicchioli Laura , Gelain Maria Elena , Ferro Silvia , Patruno Marco , Zappulli Valentina
Published: August 2020

Mammary cancer is a common neoplasm in women, dogs, and cats that still represents a therapeutic challenge. Wnt/β-catenin and Hippo pathways are involved in tumor progression, cell differentiation, and metastasis. The aim of this study was to evaluate mRNA and protein expression of molecules involved in these pathways in human (HBC), canine (CMT), and feline mammary tumors (FMT). Real-time quantitative polymerase chain reaction (qPCR) for β-catenin, CCND1, YAP, TAZ, CTGF, and ANKRD1, western blotting for YAP, TAZ, and β-catenin, and immunohistochemistry for estrogen receptor (ER), progesterone receptor (PR), ERBB2, β-catenin, and YAP/TAZ were performed on mammary tumor tissues. The protein expression of active β-catenin was higher in tumors than in healthy tissues in all 3 species. The mRNA expression of the downstream gene CCND1 was increased in HBC ER+ and CMTs compared to healthy tissues. Membranous and cytoplasmic protein expression of β-catenin were strongly negatively correlated in all 3 species. Tumors showed an increased protein expression of YAP/TAZ when compared to healthy tissues. Notably, YAP/TAZ expression was higher in triple negative breast cancers when compared to HBC ER+ and in FMTs when compared to CMTs. The mRNA expression of β-catenin, YAP, TAZ, CTGF, and ANKRD1 was not different between tumors and healthy mammary gland in the 3 species. This study demonstrates deregulation of Wnt/β-catenin and Hippo pathways in mammary tumors, which was more evident at the protein rather than the mRNA level. Wnt/β-catenin and Hippo pathways seem to be involved in mammary carcinogenesis and therefore represent interesting therapeutic targets that should be further investigated.
Institute of Transportation Engineers Guidelines versus Actual Trip and Parking Generation for a Transit-Oriented Development in an Auto-Oriented Region
Authors: Hamidi Shima , Etminani-Ghasrodashti Roya , Kang Sanggyun , Ewing Reid
Published: August 2020

The Institute of Transportation Engineers (ITE) guidelines serve as the most widely used reference for trip and parking generation estimates for any new development in the U.S.A. However, recent empirical studies question the efficacy of ITE guidelines in forecasting trip and parking generation in transit-oriented developments (TODs). Following the methodology of studies on seven TODs across the U.S.A., this study focuses on Dallas (TX), as a more auto-oriented American city, to explore the trip and parking generation at Mockingbird TOD. It finds that, with the exception of Station Park in Salt Lake City (which is really a transit-adjacent development rather than a TOD), the Mockingbird TOD has the lowest walk mode share (13.6%), the lowest bike mode share (0.22%), the lowest bus transit mode share (1.09%), and by far the lowest rail transit mode share (5.9%) of all the other seven TODs. Similarly, the Mockingbird TOD ranks first in relation to the driving mode share, with about 80% of its daily trips generated by driving. This is almost twice as many driving trips as the average of the other six TODs, which makes Mockingbird an auto-oriented TOD located in an auto-oriented region where more than 96% of commuting trips are by automobile. Still, the total automobile trip generation rate in Mockingbird is about 12% lower than the ITE estimates. Similarly, while the parking supply in Mockingbird TOD is less than 48% of the ITE recommended supply rate, its peak parking occupancy is only about 55% of the TOD supply.
Accelerated Pavement Testing to Evaluate the Reinforcement Effect of Geogrids in Flexible Pavements
Authors: Han Bingye , Polaczyk Pawel , Gong Hongren , Ma Rong , Ma Yuetan , Wei Fulu , Huang Baoshan
Published: August 2020

This study presents an accelerated pavement testing (APT) to evaluate the reinforcement effect of geogrids in flexible pavements. A full-scale conventional three-layer flexible pavement structure was constructed, and was divided into one unreinforced section and two reinforced sections with base reinforced by geogrids placed at different depth of base course. The testing program was divided into three parts: performance testing, response testing, and forensic evaluations. The performance testing recorded the development of surface permanent deformation with the number of loadings. The falling weight deflectometer (FWD) was employed to investigate deflections and moduli of flexible pavements in the response testing. The excavation of pavements was to further analyze reinforcement mechanisms. Test results demonstrated the benefits of incorporating geogrids in base course in reducing the permanent deformation and improving the modulus of base course. Compared with the unreinforced section, accumulated permanent deformations in the two reinforced sections decreased significantly, with a drop of 13%–37%, and the back-calculated moduli of the reinforced base increased by 58%–78% after APT. It was possible that sufficient permanent deformation was needed for mobilizing geogrids to constrain lateral movements of granular particles, to increase the overall structural behavior of the reinforced base course, and to improve the stress distribution on the subgrade. These interaction mechanisms were also confirmed in the pavement trench. For a pavement system consisting of a thin surface and base layer, the proper placement position of geogrids was at the base–subgrade interface for this test and loading arrangement.
Effect of Glass Bead Refractive Index on Pavement Marking Retroreflectivity Considering Passenger Vehicle and Airplane Geometries
Authors: Pike Adam M. , Datta Songjukta
Published: August 2020

Pavement marking retroreflectivity depends on several factors including but not limited to the type of retroreflective optics, binder, installation quality, marking condition, and measurement type/geometry. Texas A&M Transportation Institute (TTI) evaluated the retroreflectivity of 19 pavement marking panels, prepared with different types of glass bead at standard 30-m and non-standard measurement geometries. The non-standard geometries represented typical commercial airplane configurations. The primary purpose of the research was to evaluate the effects of the glass bead refractive index (RI) (1.5 versus 1.9) and the measurement geometry on pavement marking retroreflectivity. Results showed a decrease in retroreflectivity with an increase in observation and entrance angles for both 1.5 and 1.9 RI. The study showed higher retroreflectivity levels for high RI beads at all the geometries evaluated. The result showed that 1.9 RI beads exhibit an average of 171% (862 mcd/m2/lx) higher retroreflectivity at standard 30-m car geometry as well as 102% (193 mcd/m2/lx) higher retroreflectivity at airplane geometry compared with 1.5 RI beads. The study found that an increase in bead RI had a larger effect on retroreflectivity than did an increase in bead size. The effect of the measurement geometry on the retroreflectivity level of the markings highlights a limitation of using the 30-m car geometry to represent the visibility of markings from a pilot’s perspective. Additional work should be conducted to better assess the visibility of markings from various vehicle platforms and how to best represent the visibility through retroreflectivity measurement.
Relationships among Chemistry, Rheology, and Fracture/Fatigue Performance of Recovered Asphalt Binders and Asphalt Mixtures Containing Reclaimed Asphalt Pavement
Authors: Barghabany Peyman , Cao Wei , Mohammad Louay N. , Cooper Samuel B. , Cooper Samuel B.
Published: August 2020

Because of limited amounts of natural resources, reclaimed asphalt pavement (RAP) has gained popularity in the asphalt pavement industry to meet sustainability requirements in asphalt pavement. Concerns have been raised in relation to the intermediate temperature cracking performance of asphalt mixtures containing RAP. The objective of this study was to evaluate the intermediate temperature cracking resistance of asphalt mixtures and recovered asphalt binders containing RAP. Seven plant-produced asphalt mixtures from three transportation agencies with various RAP contents and the extracted asphalt binders were evaluated with respect to intermediate temperature cracking resistance. Asphalt binder experiments included chemical and rheological characterization of recovered asphalt binders. Chemical characterization consisted of Fourier transform infrared spectroscopy and saturates/aromatics/resins/asphaltenes component analysis. Linear amplitude sweep and time sweep tests were also performed to characterize the rheological properties of asphalt binders. Asphalt mixture experiments included four-point bending beam fatigue and semi-circular bend tests. Results indicated that, as expected, asphalt mixtures with high RAP contents resulted in asphalt binders and mixtures with reduced cracking resistance. Relationships between the asphalt binder chemical and rheological parameters and asphalt mixture cracking resistance were also investigated. Asphalt binder rheological and chemical parameters were well correlated. Asphalt binder rheological parameters showed reasonable to strong relationships with the four-point bending beam fatigue test result. The work presented in this paper is part of FHWA Transportation Pooled Fund Project TPF-5(294) “Develop Mix Design and Analysis Procedure for Asphalt Mixtures Containing High RAP and/or RAS Contents.”
Review of Usage of Real-World Connected Vehicle Data
Authors: Zhou Yun , Bridgelall Raj
Published: August 2020

GPS loggers and cameras aboard connected vehicles can produce vast amounts of data. Analysts can mine such data to decipher patterns in vehicle trajectories and driver–vehicle interactions. Ability to process such large-scale data in real time can inform strategies to reduce crashes, improve traffic flow, enhance system operational efficiencies, and reduce environmental impacts. However, connected vehicle technologies are in the very early phases of deployment. Therefore, related datasets are extremely scarce, and the utility of such emerging datasets is largely unknown. This paper provides a comprehensive review of studies that used large-scale connected vehicle data from the United States Department of Transportation Connected Vehicle Safety Pilot Model Deployment program. It is the first and only such dataset available to the public. The data contains real-world information about the operation of connected vehicles that organizations are testing. The paper provides a summary of the available datasets and their organization, and the overall structure and other characteristics of the data captured during pilot deployments. Usage of the data is then classified into three categories: driving pattern identification, development of surrogate safety measures, and improvements in the operation of signalized intersections. Finally, some limitations experienced with the existing datasets are identified.
Utilizing Agent-Based Modeling to Evaluate Operational Impacts of an Incident and Possible Alternatives on U.S. Waterways
Authors: Camp Janey , Nelson Katherine , Philip Craig E. , Moravec Miguel , Scheffler Douglas W. , Johnson Paul
Published: August 2020

Operations along inland waterways are particularly vulnerable to severe weather events which can create adverse conditions for towboat operators to manage, resulting in increased risk of accidents. However, it is challenging to know or understand the extent to which new regulations or policies on tow operating procedures may reduce impacts from a given scenario. An agent-based model (ABM) representing actual river operating procedures was developed previously to evaluate emergent characteristics and system-wide impacts arising from the interactions between disruptions, towboat operator responses, and regulations. In this work, we validate the effectiveness of the ABM model for improved decision support by comparing it with observed waterway traffic as captured by Automatic Identification System (AIS) data, then apply the model to a case study based on a 2005 incident on the Ohio River. A series of counterfactual scenarios are simulated to better understand potential impacts of the incident on waterway system performance and potential alternative outcomes given different operational responses and regulations. The analysis indicates that imposing tow movement restrictions, such as waiting for a helper towboat, under adverse river conditions can result in a general slowing of the system but with potentially lesser impacts than what would be caused if the system operates as normal and results in an incident that lasts multiple days. The analysis also indicates that the waterway system can return to normal operations within a matter of weeks.
Secondary Injuries After Pediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review With Quantitative Analysis
Authors: Zacharias Anthony J. , Whitaker John R. , Collofello Brandon S. , Wilson Benjamin R. , Unger R. Zackary , Ireland Mary Lloyd , Johnson Darren L. , Jacobs Cale A.
Published: August 2020

Background:

In the skeletally mature anterior cruciate ligament (ACL) reconstruction population, patients aged <25 years are at significantly increased risk of graft failure and injury to the contralateral ACL. Skeletal immaturity often affects graft selection and reconstruction technique.

Purpose:

To examine the incidence of ipsilateral graft failure and contralateral ACL injury in the skeletally immature patient population.

Study Design:

Systematic review and meta-analysis.

Methods:

Using the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines, we reviewed all literature that involved ACL reconstruction performed on skeletally immature patients between May 1976 and May 2019. Patient demographics, surgical technique, and the prevalence of ipsilateral graft failure or subsequent contralateral ACL injury were recorded. Ipsilateral, contralateral, and secondary ACL injuries were then compared between sexes via chi-square tests.

Results:

A total of 24 articles (1254 children; 1258 knees) met inclusion criteria for analysis. Ipsilateral graft failures occurred in 105 of 1258 patients (8.3%), and there were no statistically significant sex differences in the prevalence of graft failures (female, 9.7%; male patients, 7.1%; P = .14). The prevalence of contralateral ACL injury was significantly greater in female (29/129; 22.5%) than male (18/206; 8.7%; P = .0004) patients in the 9 studies that reported contralateral injury. Skeletally immature female patients were at significantly increased risk of contralateral ACL injury (odds ratio = 3.0; P = .0006) when compared with their male counterparts.

Conclusion:

In the literature to date, 1 in 3 female skeletally immature patients experienced an ipsilateral graft failure or contralateral ACL injury. Regardless of sex, the 24% prevalence of secondary injury after pediatric ACL reconstruction is almost identical to previously published secondary injury rates in skeletally mature patients <25 years old. As such, skeletal maturity alone does not seem to be a determinant of secondary injury; however, there is a clear need to improve postoperative rehabilitation, activity progression, and return-to-play testing to allow a safe return to sports that protects the long-term health of the reconstructed and contralateral limbs, especially for female patients.
Ulnar Collateral Ligament Tear Location May Affect Return-to-Sports Rate but Not Performance Upon Return to Sports After Ulnar Collateral Ligament Reconstruction Surgery in Professional Baseball Players
Authors: Erickson Brandon J. , Carr James , Chalmers Peter N. , Vellios Evan , Altchek David W.
Published: August 2020

Background:

The number of ulnar collateral ligament (UCL) tears in professional baseball players is increasing. UCL reconstruction (UCLR) is the treatment of choice in players with failed nonoperative treatment who wish to return to sports (RTS). It is unknown if UCL tear location influences the ability of players to RTS or affects their performance upon RTS.

Purpose/Hypothesis:

The purpose was to compare the RTS rate and performance upon RTS in professional baseball players who underwent UCLR based on UCL tear location (proximal vs distal). It was hypothesized that no difference in RTS rate or performance upon RTS will exist between players with proximal or distal UCL tears.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

All professional baseball players who underwent primary UCLR by a single surgeon between 2016 and 2018 were eligible for inclusion. Players with purely midsubstance tears or revision UCLR were excluded. Tear location was determined based on preoperative magnetic resonance imaging (MRI) and intraoperative findings. RTS rate and performance were compared between players with proximal versus distal UCL tears.

Results:

Overall, 25 pitchers (15 proximal and 10 distal tears) and 5 position players (2 proximal and 3 distal) underwent primary UCLR between 2016 and 2018. Of the 25 pitchers, 84% were able to RTS. Of the 5 position players, 80% were able to RTS. Among the total cohort of pitchers and position players, 12 out of 17 (71%) players with proximal tears were able to RTS, while of the 13 distal tears, 13 out of 13 (100%) players were able to RTS ( P = .05). With regard to performance data, pitchers with distal tears had higher utilization postoperatively and, as such, allowed statistically more hits ( P = .03), runs ( P = .015), and walks ( P = .021) postoperatively. However, the WHIP ([walks + hits]/innings pitched) was not different between players with proximal or distal tears, indicating that efficacy in games was not significantly different between groups.

Conclusion:

Professional baseball players who sustain a distal UCL tear and undergo UCLR may be more likely to RTS than those who sustain a proximal UCL tear and undergo UCLR. Players with distal UCL tears who underwent UCLR saw higher utilization postoperatively than those with proximal UCL tears. Further work is needed in this area to confirm this result.
Home Sharing and Crime Across Neighborhoods: An Analysis of Austin, Texas
Authors: Roth Jeffrey J.
Published: August 2020

Home sharing is an increasingly popular alternative to hotels, in which individuals rent all or a portion of their residence as short-term accommodations for travelers. Criminological research has examined the relationship between crime and visitors in a variety of contexts, but very few studies have explored possible associations between home sharing and crime. Grounded in social disorganization and routine activities theories, this study adds to the literature by evaluating the relationship between home sharing density and several types of crime across census tracts in Austin, Texas. The analysis also controls for the effects of tourism, alcohol establishments, and other relevant sociodemographic factors. The results indicate that the sharing of entire units was not associated with crime rates for any of the offense types. Levels of private rooms, however, were positively associated with one of the offenses. Although far more research is needed on the topic, these results are discussed in light of the other notable study on the topic to suggest early conclusions about home sharing and crime.
Evaluation of skin irritation following weathered crude oil exposure in two mouse strains
Authors: Kemp Jesse M , Luckett-Chastain Lerin R , Calhoun Kaitlin N , Frempah Benjamin , Schartz Tayler R , Harty Linda E , Kemp Philip M , Gallucci Randle M
Published: August 2020

Petroleum crude oil spills are common and vary in size and scope. Spill response workers throughout the course of remediation are exposed to so-called weathered oil and are known to report diverse health effects, including contact dermatitis. A murine model of repeated exposure to weathered marine crude oil was employed utilizing two strains of mice, C57BL/6 and BALB/c, to investigate the pathology of this irritant and identify the principal hydrocarbon components deposited in skin. Histopathology demonstrated clear signs of irritation in oil-exposed skin from both mouse strains, characterized by prominent epidermal hyperplasia (acanthosis). BALB/c mice exposed to oil demonstrated more pronounced irritation compared with C57BL/6 mice, which was characterized by increased acanthosis as well as increased inflammatory cytokine/chemokine protein expression of IL-1β, IL-6, CXCL10, CCL2, CCL3, CCL4, and CCL11. A gas chromatography/mass spectrometry method was developed for the identification and quantification of 42 aliphatic and EPA priority aromatic hydrocarbons from full thickness skin samples of C57BL/6 and BALB/c mice exposed to oil samples. Aromatic hydrocarbons were not detected in skin; however, aliphatic hydrocarbons in skin tended to accumulate with carbon numbers greater than C16. These preliminary data and observations suggest that weathered crude oil is a skin irritant and this may be related to specific hydrocarbon components, although immune phenotype appears to impact skin response as well.
An Active In-Home Physician Model of Palliative Care and Its Resulting Performance Indicators Related to Home Deaths, Unplanned Emergency Department Visits and Unplanned Hospital Admissions
Authors: Webber Colleen , Valiulis Aurelia Ona , Tanuseputro Peter , Schulz Valerie , Apramian Tavis , Schreier Gil , Hamilton Kirk
Published: August 2020

Background:

Limited research has characterized team-based models of home palliative care and the outcomes of patients supported by these care teams.

Case presentation:

A retrospective case series describing care and outcomes of patients managed by the London Home Palliative Care Team between May 1, 2017 and April 1, 2019.

Case management:

The London Home Palliative Care (LHPC) Team care model is based upon 3 pillars: 1) physician visit availability 2) active patient-centered care with strong physician in-home presence and 3) optimal administrative organization.

Case outcomes:

In the 18 month study period, 354 patients received care from the London Home Palliative Care Team. Most significantly, 88.4% ( n = 313) died in the community or at a designated palliative care unit after prearranged direct transfer; no comparable provincial data is available. 21.2% ( n = 75) patients visited an emergency department and 24.6% ( n = 87) were admitted to hospital at least once in their final 30 days of life. 280 (79.1%) died in the community. These values are better than comparable provincial estimates of 62.7%, 61.7%, and 24.0%, respectively.

Conclusion:

The London Home Palliative Care (LHPC) Team model appears to favorably impact community death rate, ER visits and unplanned hospital admissions, as compared to accepted provincial data. Studies to determine if this model is reproducible could support palliative care teams achieving similar results.
Peer Victimization and Anxiety in Youth: A Moderated Mediation of Peer Perceptions and Social Self-Efficacy
Authors: Victoira L. Purcell , Andrews Jac J. W. , Nordstokke David
Published: August 2020

The central objective of the study was to investigate a moderated mediation model addressing social cognitive mechanisms that account for the association between peer victimization and anxiety. A sample of 81 youth ( M age = 12.78, SD = 0.88) completed questionnaires assessing peer victimization, anxiety, social self-efficacy, and peer perceptions. Reports of peer victimization were associated with anxiety symptoms. Moreover, social self-efficacy partially mediated the relationship between peer victimization and anxiety. Lastly, the perception of school peers moderated the mediation process between peer victimization and anxiety via social self-efficacy. These findings suggest that social contextual variables (e.g., peer victimization and perception of school peers) and negative self-evaluations (e.g., social self-efficacy) are risk factors for anxiety symptom severity in youth. Limitations and practical implications were discussed.
RGD peptide-mediated liposomal curcumin targeted delivery to breast cancer cells
Authors: Mahmoudi Reza , Ashraf Mirahmadi-Babaheidri Seyedeh , Delaviz Hamdollah , Fouani Mohamad Hassan , Alipour Mohsen , Jafari Barmak Mehrzad , Christiansen Gunna , Bardania Hassan
Published: August 2020

In this study, turmeric's active ingredient (Curcumin) was encapsulated into RGD modified Liposomes (RGD-Lip-Cur) its cytotoxic effect on the breast cancer cell line (MCF-7) was evaluated by MTT, flow cytometry and Caspase assay. Liposomes were characterized using transmission electron microscopy (TEM). Results demonstrated that the liposomes were spherical in shape, ranging from 70 to 100 nm. MTT assay revealed that RGD-Lip-Cur had a significant cytotoxic effect on MCF-7 cells at concentrations of 32, 16 and 4 μg/ml compared to Lip-Cur (P < 0.05) and curcumin (P < 0.01). The apoptosis assay demonstrated that RGD-Lip-Cur induces the apoptosis in MCF-7 cells (39.6% vs 40.2% for initial and secondary apoptosis) significantly more than Lip-Cur (67.7% vs 9.16% for initial and secondary apoptosis) and free curcumin (7.84% vs 38.8% for initial and secondary apoptosis). Moreover, caspase assay showed that RGD-Lip-Cur activates caspase 3/7 compared to Lip-Cur (P < 0.05) and free curcumin (P < 0.01). The RGD-Lip-Cur was similar to the control group and had no significant cytotoxicity effect. It is concluded that RGD-Lip-Cur as a novel carrier have high cytotoxicity effect on breast cancer cell line (MCF-7).
One and the Same? A Systematic Literature Review of Residential Property Investor Types
Authors: Özogul Sara , Tasan-Kok Tuna
Published: August 2020

This article presents a systematic literature review on residential property investor types in selected social science disciplines and critically evaluates the status quo of academic engagement within this diverse group of property market actors. A recurring critique in recent years has been the minimal acknowledgment of investor heterogeneity particularly in relation to urban development and the financialization of housing. Yet, to date, there is no systematic evidence supporting these contentions. Therefore, we conducted an exhaustive literature review of residential investment landscapes through the Web of Science citation database in the following fields: Urban and regional planning, geography, sociology, urban studies, public administration, and economics. Subsequently, we methodically searched for the types of investors addressed, and investor categories employed, in journal articles published between 2000 and 2019. Following a meta-categorization of the results, we demonstrate how existing literature differentiates investors in terms of their spatial scale of operation, size and social composition, investment object and finance, or investment and social behavior. Additionally, we highlight the key topics and issues addressed in the reviewed literature within each meta-category. We propose to turn the four meta-categories into a multidimensional analytical framework as a point of departure for a more nuanced and in-depth understanding of investor differentiations, a tool that is urgently needed in Planning Studies and related disciplines. Furthermore, we argue that mixed method approaches combining hard and quantifiable with soft behavioral investor characteristics, as well as institutional analyses combining structural considerations with actors’ agency, are indispensable to disentangle contemporary residential property market dynamics.
The Viability of Tuition-Free Community College
Authors: Ison Matthew P.
Published: August 2020

Free higher education has become a major policy discussion of the past few years, one that is often debated or supported along partisan lines. Those supporting this policy initiative often point to the rising cost of a college education and the barrier it creates for underrepresented populations hoping to access higher education. Others point to a broken financial aid system that leaves more individuals financing their education through student loans, adding to a massive national loan debt now exceeding a trillion dollars. Various arguments for and against a free-tuition program within the American higher education system are addressed. While an argument can be made that all public American higher education should be tuition-free, limiting a large-scale federal program to the American community college has economic and political implications that could make the policy more feasible for a larger percentage of the American public.
The Critical Business School and the University: A Case Study of Resistance and Co-optation
Authors: Parker Martin
Published: August 2020

Can a school of ‘critical management studies’ survive in the context of a marketising university which relies heavily on business education for its income? This paper explores the case of a UK management school which attempted to do that and survived for 13 years with a clearly ‘critical’ project. As someone who worked in the school, but left some time ago, I evaluate its successes and failures, concluding that the radicalism of its research and publication strategy was not paralleled by an understanding of the politics of the institution and its environment. This led to a posture of ‘defensive isolation’ which ultimately made the school vulnerable to changes in the strategies of senior university management.
Prediction of performance deterioration of rolling bearing based on JADE and PSO-SVM
Authors: Zan Tao , Liu Zhihao , Wang Hui , Wang Min , Gao Xiangsheng , Pang Zhaoliang
Published: August 2020

In order to improve the prediction accuracy of performance degradation trends of rolling bearings, a method based on the joint approximative diagonalization of eigen-matrices (JADE) and particle swarm optimization support vector machine (PSO-SVM) was proposed. Firstly, the features of the time-domain, frequency-domain, and time-frequency-domain eigenvalues of the vibration signal corresponding to the entire life cycle of the rolling bearing are extracted, and the performance degradation parameters are initially selected by using the monotonicity parameter. Then, a fusion feature that can effectively represent the performance degradation is obtained by using the JADE method. Finally, the prediction model based on PSO-SVM is constructed to predict the performance degradation trend. By comparing with the prediction results obtained by other classical methods, it can be proved that this method can accurately predict the performance degradation trend and the remaining useful life (RUL) of rolling bearings under small sample sizes, and has considerable application potentials.
Research on the rolling contact fatigue life of the bearing considering the friction effect
Authors: Zhang Yimin , Liu Yongzhen
Published: August 2020

In this paper, a theoretical model is proposed to analyze the friction effect on the rolling contact fatigue (RCF) life of the angular contact ball bearing (ACBB). Firstly, the quasi-static model without race control hypothesis is introduced to study the load characteristics of the ACBB under different loading conditions. Then, the friction coefficient is quantitatively calculated by analyzing the relation between the gyroscopic torque and the sphere-race contact load. The effects of the axial load, radial load, torque load and rotating speeds on the friction coefficient, the maximum value of the sub-surface von Mises stress (SSVS) and the maximum peak-peak value of the sub-surface shear stress (SSSS) are subsequently investigated. The results show that they can significantly affect the friction coefficient and further influence the stress field beneath the contact surface. Further studies illustrate that the friction coefficient cannot affect the maximum peak-peak value of the SSSS but can change the distribution of the SSVS field. The relative RCF life of the sphere-race contact is calculated and the published studies confirm the accuracy of the calculation.
Super-twisting algorithm second-order sliding mode control for collision avoidance system based on active front steering and direct yaw moment control
Authors: Liu Jun , Gao Liang , Zhang Junjie , Yan Feng
Published: August 2020

Active collision avoidance system has received more and more attraction, which has the capability to avoid potential accidents and reduce driver burden. This paper proposes an active collision avoidance system which consists of a path planner and a coordinated lateral controller. In the path planner, cubic B-spline is developed to obtain collision-free trajectories to bypass the obstacle by steering. Based on this, a coordinated lateral dynamic control of autonomous ground vehicles is presented to improve the accuracy and robustness of path following and simultaneously ensure vehicle stability via active front steering and direct yaw moment control. Then, second-order sliding mode control, based on super-twisting algorithm, is applied to reduce lateral offset and heading angle deviation as much as possible and avoid chattering phenomenon of tradition sliding mode control. Meanwhile, a new form of sliding mode control based on improved reaching law is devoted to forcing the vehicle state sideslip angle and yaw rate to stability envelope with less chattering in the case of low road friction coefficient. Eventually, the effectiveness and robustness of active collision avoidance system against external disturbance and parametric uncertainties are confirmed through different test cases in the MATLAB/Simulink simulation platform.
Novel technology concepts and architecture for on-board condition-based monitoring of railway running gear: The RUN2Rail vision
Authors: Jarillo Julián Martín , Moreno Juan , Alfi Stefano , Barcet Sylvain , Bouvet Pascal , Bruni Stefano , Cervello Steven , Costa Bruno , Licciardello Riccardo
Published: August 2020

Bogies are key subsystems for rolling stock safety and, therefore, meaningful and objective data concerning their condition is of paramount importance for railway operation. These subsystems experience severe service conditions causing wear, damage and degradation of components and affecting the vibrations to which the passengers are exposed. As such, safe and reliable operation, together with a high level of comfort for the passengers, can only be assured by an in-depth, data-based and comprehensive maintenance of the bogie components. In this perspective, advanced health monitoring of the running gear plays a fundamental role as the enabler for condition-based maintenance strategies. This paper reports about work performed in the RUN2Rail project aimed at formulating new concepts for the condition monitoring of the running gear. Three case studies are addressed: wheelsets, powertrain and suspension components. For these cases, the suitable choice and location of sensors is investigated and innovative fault detection and fault classification methods are proposed and preliminarily validated by means of numerical experiments and laboratory tests. A concise outline of the impacts and benefits of each proposed condition monitoring application is also provided.
Studies on the low frequency vibration of the suspension system for heavy trucks under different operation conditions
Authors: Jiao Renqiang , Nguyen Vanliem
Published: August 2020

This study proposed a 4 degrees of freedom dynamic model for the two-axle heavy truck to investigate the low frequency vibration characteristics of the suspension system. Unlike the previous research works, the vibration equations of heavy truck model were solved in the frequency domain instead of the traditional time domain based on a calculation method in the complex domain. In order to evaluate the vibration characteristics of the suspension system, parameters of the vehicle velocity, wavelength of the road, load condition, stiffness coefficient, and height of the random road surfaces were then taken into account to clarify their influence on the acceleration frequency characteristics of the suspension system, respectively. The simulation results reveal that the resonant frequency of the suspension system was not affected by the vehicle velocities and road surface profile, while it is greatly influenced by the loading conditions and stiffness of the suspension system. In addition, under different working conditions, the acceleration frequency response characteristics of the vertical and pitch vibration of the heavy truck body and the vertical vibration of the front and rear axles were greatly affected, especially when the vehicle was traveling on the rod of level C at a speed of 30 m s−1.
Unscented Kalman filtering method for scheduling photovoltaic power generation system fluctuations
Authors: Li Zheng , Zhang Liping , Zhang Rui , Wang Xin , Xue Zengtao , Sun Hexu
Published: August 2020

For the intermittent nature of renewable resources (such as wind and solar), smooth power fluctuations are required before the energy conversion system can be injected into the grid. The battery system is a typical smoothing control method for photovoltaic power. The long-term overcharge and overdischarge make the battery energy storage scheme unattractive. In this paper, the output power fluctuation of the photovoltaic power generation system is smoothed based on the unscented Kalman filter (UKF) method combined with the fuel cell operating characteristics. This coordination method affects the UKF situation through the feedback of state of charge (SOC) and the power of the battery system. Not only can it better meet the load characteristics, but it can also make the SOC automatically correct the battery system to prevent overcharge and overdischarge. The meteorological load data was used to verify the superiority of the method.
Glacier and ocean variability in Ata Sund, west Greenland, since 1400 CE
Authors: Ekblom Johansson Fanny , Wangner David J , Andresen Camilla S , Bakke Jostein , Støren Eivind Nagel , Schmidt Sabine , Vieli Andreas
Published: August 2020

To improve knowledge of marine-terminating glaciers in western Greenland, marine sediment cores from the Ata Sund fjord system, hosting two outlet glaciers, Eqip Sermia and Kangilerngata Sermia, were investigated. The main objective was to reconstruct glacial activity and paleoceanographic conditions during the past 600 years. Ice-rafted debris (IRD) was quantified by wet-sieving sediment samples and by using a computed tomography scan. Variability in relative bottom water temperatures in the fjord was reconstructed using foraminiferal analysis. On the basis of this, three periods of distinct glacial regimes were identified: Period 1 (1380–1810 CE), which covers the culmination of the Little Ice Age (LIA) and is interpreted as having advanced glaciers with high IRD content. Period 2 (1810–1920 CE), the end of the LIA, which was characterised by a lowering of the glaciers’ calving flux in response to climate cooling. During Period 3 (1920–2014 CE), both glaciers retreated substantially to their present-day extent. The bottom water temperature started to decrease just before Period 2 and remained relatively low until just before the end of Period 3. This is interpreted as a local response to increased glacial meltwater input. Our study was compared with a study in Disko Bay, nearby Jakobshavn Glacier and the result shows that both of these Greenlandic marine-terminating glaciers are responding to large-scale climate change. However, the specific imprint on the glaciers and the different fjord waters in front of them result in contrasting glacial responses and sediment archives in their respective fjords.
Urinary C3d is elevated in patients with active Lupus nephritis and a fall in its level after 3 months predicts response at 6 months on follow up
Authors: Ganguly Sujata , Majumder Sanjukta , Kumar Sandeep , Gupta Ranjan , Muhammed Hafis , Shobha Vineeta , Aggarwal Amita , Misra Ramnath
Published: August 2020

Introduction

Complement activation is central to the pathogenesis of lupus nephritis (LN). Low serum complement C3 and C4, are traditionally used as markers of lupus disease activity in general and LN in particular. In this study we prospectively measured plasma and urine C3d and C4d, degradation products of C3 and C4 corrected to creatinine in a cohort of biopsy proven LN in a longitudinal fashion for its correlation with disease activity.

Methods

Twenty eight biopsy proven active lupus nephritis (AN) were recruited along with four inactive nephritis (IN) and 10 healthy controls (HC). Plasma and urine were collected at baseline, prior to induction treatment and 3 months later. Clinical measures of disease activity, Systemic lupus erythematosus disease activity index 2000 (SLEDAI 2K), renal SLEDAI, serum C3, C4 and antibodies to ds DNA, urine protein and creatinine excretion (UP/UC) were collected. Plasma and urine C3d and C4d were measured using ELISA and normalized to spot urine creatinine value.

Results

Twenty eight AN of median age of 26.5 (20–31.50) years and disease duration of 3 (0.7–5) years were enrolled. The median urinary C3d/creatinine before treatment was 388.20 (48.98–1296) ng/mg which fell significantly to 62.69 (28.04–502.4) ng/mg at 3 months followup (p-0.01). The baseline values for the active renal disease was significantly different from IN group (9.9 (4.5–46.53 ng/mg) p-0.00). Treatment responders (partial and complete) at 6 months showed a significant fall in urinary C3d at 3 months whereas non responders had a non significant change in value. There was a significant correlation of urine C3d/creatinine with SLEDAI2K (r-0.433, p-0.00), renal SLEDAI (r-0.356, p-0.00), UP/UC ratio (r-0.489, p-<0.0001) but no significant correlation with C3 or C4. There was a significant fall in the median values of plasma C3d from 791.1 (516.0.00–1550.43) µg/ml to 338.52 (211.35–525.82) (p-0.00) µg/ml at the end of 3 months. The values showed a significant correlation with SLEDAI 2K, renal SLEDAI, UP/UC along with a significant negative correlation with C3 and C4.

Conclusion

Urinary C3d/creatinine levels and plasma C3d levels can be used as biomarker of disease activity and treatment response.
Cut off point of neutrophil-to-lymphocyte ratio as a marker of active disease in systemic lupus erythematosus
Authors: Firizal Akhmad Syaikhu , Sugianli Adhi Kristianto , Hamijoyo Laniyati
Published: August 2020

Aim

We aimed to measure sensitivity, specificity, and to determine the cut-off value (COV) ratio of neutrophil-to-lymphocyte (NLR) in patients with active systemic lupus erythematosus (SLE).

Methods

A cross sectional study was conducted using the retrospective data from Hasan Sadikin Lupus Registry (HSLR). The inclusion criteria were SLE patients aged 18 years or older who had documented data of neutrophil, lymphocyte, and SLE disease activity index (SLEDAI). Patients with infections, malignancies, and other inflammatory diseases recorded in registry were excluded. SLEDAI with a score of ≤ 4 is considered inactive and score of > 4 is considered active. The neutrophil-to-lymphocyte ratio was calculated by dividing the absolute number of neutrophils by the absoulte number of lymphocytes. Receiver Operating Characteristic (ROC) curve was used to analyze and determine optimal COV of NLR.

Results

The total sample in this study were 112 subjects with a dominant of female (95.54%) and the mean age of 34.45 ± 9.40 years. The median of SLEDAI was 4.5 with a range from 0 to 16, while the median of NLR was 2.68 with a range of 0.59 to 19.02. The ROC analysis showed the optimal cut-off in this study was 2.94 with sensitivity and specificity as high as 60.71% and 76.79%, respectively.

Conclusion

Neutrophil-to-lymphocyte ratio with cut off value of 2.94 can be used to determine active disease of systemic lupus eythematousus.
Synthesis, characterization, and application of polypyrrole/TiO2 composites in photocatalytic processes: A review
Authors: Amorim Suélen M , Steffen Gabriel , de S Junior Joel MN , Brusamarello Claiton Z , Romio Ana P , Domenico Michele D
Published: August 2020

Hybrid materials composed of semiconductor oxide metals and conducting polymers have been highlighted as a new class of materials, with superior properties compared to their pure constituents. Among the studied composites to photocatalytic applications, the hybrids of titanium dioxide (TiO2) and polypyrrole (PPy) are promising due to several advantages over the pure TiO2 nanoparticles. The PPy/TiO2 composite has been effectively synthetized by chemical polymerization methods as in situ polymerization, photopolymerization, electrochemical polymerization, and molecular imprinting polymerization (MIP). All the cited methods appear to be effective in reducing the band gap energy, which suggests an increase in the formation of photoexcited electron-hole pairs and, consequently, an improvement of the light absorption in the visible region (400–700 nm). In addition, the doping of PPy/TiO2 with noble metals improves the separation of charges in the semiconductor particle, inhibiting the recombination of photogenerated electron-hole pairs. All advantages are evidenced by the characterization results of SEM, TEM, HRTEM, UV-vis DRS, FTIR, XRD, PL, TGA and electrical properties. Finally, results from literature present that PPy/TiO2 composites have better photocatalytic activity than the pure TiO2, being an alternative photocatalyst promising for visible light applications. Thus, this work presents a review of the synthesis, characterization, and application of PPy/TiO2 composites in the photocatalytic processes.
The many roles of change agency in the game of green path development in the North
Authors: Sotarauta Markku , Suvinen Nina , Jolly Suyash , Hansen Teis
Published: August 2020

The rapidly expanding stream of path development studies recognises that translating observations from past paths to conscious path creation requires conceptually linking agency to path development frameworks. Actors frame issues about and for the future, coordinate their actions in the present and make sense of what may have transpired in the past. The main objective of the paper is to explore the roles that actors play in green path development by answering the following main research questions: (a) Who are the core actors in green path development in the Nordic regions, ie. in industrial development around products, solutions or technologies that make regional economies more sustainable? (b) What are their main roles in relation to other actors? (c) What are the differences and similarities between the regions in terms of agency? The paper explores whether similar actors take on different roles in different regions and whether different actors may assume similar roles. For the empirical analysis, we identified seven roles in change agency. The empirical results showed that institutional entrepreneurship was the core of change agency in conjunction with innovative entrepreneurship and place-based leadership. The other four roles supported path development efforts. The results also show that institutional entrepreneurship is not a solo activity but a collective form of agency and that well-functioning shared institutional entrepreneurship may have a chance to change institutions for green path development.