bluuebunny/crossref_metadata_2025 huggingface dataset:
The National Economic Association at 50: Where Have We Come From and Where Are We Going?
Authors: Simms Margaret C.
Published: May 2020

The National Economic Association was founded as the Caucus of Black Economists in 1969. The organization was formed to address the underrepresentation of Black economists in the American Economic Association and in the profession at large. This article reviews key issues raised and how they were addressed. It also makes suggestions for future directions the NEA might take.
Real time assessment of power quality issues in 11 kV/440 V distribution feeder using distribution static synchronous compensator
Authors: Srinivasan Suresh , Krishnamoorthy Murugaperumal , Pongiannan RK , Jeyasudha S
Published: May 2020

The effects of power quality (PQ) issues in a distribution feeder occur due to abnormal load condition. In this paper, first, the real time PQ issues in an 11 kV/440 V distribution feeder are measured and analyzed by PQ analyzers. The sudden load fluctuations in the distribution system result in different PQ issues such as voltage sag/swell, transient, flicker and harmonics. Then, an improved interactive distribution static synchronous compensator (D-STATCOM) is installed in distribution feeder to mitigate the PQ issues. A novel control algorithm will operate the interactive D-STATCOM in voltage control mode (VCM) or current control mode (CCM). At normal operating conditions, the D-STATCOM operates in CCM, during abnormal condition the D-STATCOM will operates in VCM to mitigates the PQ issues. The D-STATCOM is modeled and simulated in MATLAB-SIMULINK environment. The field programmable gate array (FPGA)-based laboratory prototype D-STATCOM has been developed to validate the function of the controller.
On the Effects of Constitutive Properties and Roughness of a Hard Inclusion in Soft Tissue on B-mode Images
Authors: Karve Pranav M. , Duddu Ravindra , Tierney Jaime , Dei Kazuyuki , Hsi Ryan , Byram Brett
Published: May 2020

We perform finite element modeling of pulse-echo ultrasound of a hard inclusion in a soft tissue to gain a better understanding of B-mode image brightness characteristics. We simulate a pressure wave emitted by an ultrasound transducer through the inclusion-tissue medium by prescribing suitable boundary conditions, and collect the scattered wave response to simulate the behavior of the transducer array used for pulse-echo ultrasound. We form B-mode images from simulated channel data using standard delay and sum beamforming. We establish the accuracy of the finite element model by comparing the point spread function with that obtained from Field II ultrasound simulation program. We also demonstrate qualitative validation by comparing the brightness characteristics of rough and smooth surfaced circular inclusions with experimental images of a cylindrical metal tool immersed in a water tank. We next conduct simulation studies to evaluate changes in B-mode image brightness intensity and contrast related to different constitutive properties, namely, compressibility of the inclusion, impedance contrast between the host and inclusion, and surface roughness of the inclusion. We find that the intensity observed behind a hard inclusion in the axial direction is strongly affected by the compressibility and roughness of the inclusion. Also, the perceived width of the stone based on the intensity is greater for rougher stones. Our study indicates that imaging of compressible inclusions may benefit from targeted B-mode image forming algorithms. Our modeling framework can potentially be useful in differentiating hard inclusions from surrounding parenchyma, and for classifying kidney stones or gallstones.
The Working of Heteronormativity: Transnational Remarriage as Pragmatic Strategy
Authors: Quah Sharon Ee Ling
Published: May 2020

This article uses empirical findings derived from in-depth interviews with remarried individuals in Singapore to present a sociological analysis on transnational remarriage. Contributing to existing scholarship on remarriage, the article discusses specifically transnational remarriages where transnational divorcees enter another transnational marriage. Adopting a transnational, intersectional feminist perspective, the article analyzes anecdotal accounts of remarried individuals to illustrate how unequal effects of globalization and the intersection of nationality, class, and gender shape the conditions under which transnational divorcees remarry and pursue happiness. The empirical discoveries reveal how the remarried participants veer off the normative pathway of heteronormative modern marriage where one would fall in love, marry, and enjoy the companionship of a soul mate. Transnational remarriage is instead employed as a pragmatic strategy for attaining various happiness goals, namely, restored masculinity, social recognition, mobilities, and family reunification, thereby challenging dominant meanings of modern marriage. Having said that, the participants’ anecdotes show that their happiness goals continue to be lodged within the framework of heteronormative marriage though their pathways may differ from the normative ones. Their accounts of their motivations to remarry and meanings of marriage reveal the profound effects of heteronormativity in their decisions and trajectories. The article thereby offers a critique of heteronormativity through a feminist gaze on remarriage.
Who Is the Subject of Mission? The Need to Decolonize Mission From the Perspective of “the Margins”
Authors: Knuth Anton
Published: May 2020

The critique of mission history often involves perpetuating the overestimated impact of the missionaries from opposite sides. It was not so much the missionaries who mattered, but what mattered more was whether the people were responding to the message or not. Today we see the translating function of the missionaries in a clearer way and the people’s reception as the crucial factor in the process of modern Christianization. The World Council of Churches in its declaration “Together Towards Life” (2013) separates mission from its entanglement with colonialism as a mission from the margins by grounding it in the triune God (missio Dei), but it seems to overlook the contributing factor of the people as the human subject of the Christianization process. Instead of following a simple input-impact model, we have to acknowledge more those who were adapting themselves to the Christian faith from within their own context.
Hepatocellular carcinoma and multiple myeloma with elevated globulin: a case report and literature review
Authors: Xu Ling , Yang Wei , Shu Ye-Fei , Xu Xiao-Feng
Published: May 2020

A 60-year-old male patient presented with a serum α-fetoprotein (AFP) level of 2940.5 ng/mL accompanied by a significant increase in serum globulin. Hepatitis B virus (HBV) DNA was 2.85 × 103 (normal value <1.0 × 103). B-mode ultrasound and magnetic resonance imaging showed characteristic manifestations and he was clinically diagnosed with hepatocellular carcinoma in January 2015. He received radiofrequency ablation and tenofovir disoproxil anti-HBV therapy and his serum AFP and globulin levels were significantly reduced. In March 2018, he presented at our Hematology Department with fatigue and a pale complexion. At that time, his serum AFP level was normal, with hemoglobin 61 g/L and globulin 64.7 g/L. He was diagnosed with multiple myeloma (MM) by bone marrow examination, and immunofixation electrophoresis. The patient received PCD chemotherapy (bortezomib 2.0 g/dL on days 1, 4, 8, and 11 plus cyclophosphamide 0.3 g/dL on days 1–4 plus dexamethasone 20 mg/dL on days 1–2, 4–5, 8–9, and 11–12). The patient finally died of MM complicated by disseminated intravascular coagulation.
Response of a comprehensive cancer center to the COVID-19 pandemic: the experience of the Fondazione IRCCS–Istituto Nazionale dei Tumori di Milano
Authors: Valenza Franco , Papagni Gabriele , Marchianò Alfonso , Daidone Maria Grazia , De’Braud Filippo , Colombo Mario Paolo , Frignani Andrea , Galmozzi Gustavo , Ladisa Vito , Pruneri Giancarlo , Salvioni Roberto , Spada Pierangelo , Torresani Michele , Rinaldi Oliviero , Manfredi Stefano , Votta Marco , Apolone Giovanni
Published: May 2020

Background:

The rapid spread of coronavirus disease (COVID-19) is affecting many countries. While healthcare systems need to cope with the need to treat a large number of people with different degrees of respiratory failure, actions to preserve aliquots of the healthcare system to guarantee treatment to patients are mandatory.

Methods:

In order to protect the Fondazione IRCCS–Istituto Nazionale dei Tumori di Milano from the spread of COVID-19, a number of to-hospital and within-hospital filters were applied. Among others, a triage process to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positivity in patients with cancer was developed consisting of high-resolution low-dose computed tomography (CT) scan followed by reverse transcription polymerase chain reaction (RT-PCR) detection of SARS-CoV-2 in nose–throat swabs whenever CT was suggestive of lung infection. To serve symptomatic patients who were already admitted to the hospital or in need of hospitalization while waiting for RT-PCR laboratory confirmation of infection, a COVID-19 surveillance zone was set up.

Results:

A total of 301 patients were screened between March 6 and April 3, 2020. Of these, 47 were hospitalized, 53 needed a differential diagnosis to continue with their cancer treatment, and 201 were about to undergo surgery. RT-PCR was positive in 13 of 40 hospitalized patients (32%), 14 of 52 day hospital patients (27%), and 6 of 201 surgical patients (3%).

Conclusion:

Applying filters to protect our comprehensive cancer center from COVID-19 spread contributed to guaranteeing cancer care during the COVID-19 crisis in Milan. A surveillance area and surgical triage allowed us to protect the hospital from as many as 33 patients infected with SARS-CoV-2.
Double coating of graphene oxide–polypyrrole on silk fibroin scaffolds for neural tissue engineering
Authors: Wang Yuqing , Yu Haoran , Liu Haifeng , Fan Yubo
Published: May 2020

The desired scaffolds for neural tissue engineering need to have electrical conductivity. In this study, we doubly coated graphene oxide and polypyrrole on silk fibroin scaffolds (SF@GO-PPY) by a facile method to improve its electrical conductivity. The graphene oxide–polypyrrole double coating was distributed homogeneously on silk fibroin scaffolds. Compared with silk fibroin scaffolds, the SF@GO-PPY scaffold showed higher electrical conductivity, electrochemical property, mechanical property, and thermal stability. The π–π stacking interaction between polypyrrole and graphene oxide might contribute to the superior conductive and electrochemical property of the SF@GO-PPY scaffold. Moreover, in vitro cell experiment carried out on SH-SY5Y cells showed no cytotoxicity of all the scaffolds. Thus, the results indicated that the SF@GO-PPY scaffold might be a suitable candidate for the application in neural regeneration field.
Estimating the Wage Premium to Supervision for Middle Managers in Different Contexts: Evidence from Germany and the UK
Authors: Leonida Leone , Marra Marianna , Scicchitano Sergio , Giangreco Antonio , Biagetti Marco
Published: May 2020

The analysis of wage distribution has attracted scholars from different disciplines seeking to develop theoretical arguments to explain the upward or downward trend. In particular, how the middle management wage premium changes in different contexts is a relatively neglected area of research. This study argues that wage distribution changes in different contexts, representing different forms of capitalism. To shed light on this, we considered the size and the shape of the wage premium to supervision paid to middle managers in Germany and the UK. We find evidence of two forms of context: middle managers are paid differently for the same task according to the economy where they work; of this amount, about half of the difference is related to the context. We frame the analysis within the literature on varieties of capitalism.
Scientists as comedians: The effects of humor on perceptions of scientists and scientific messages
Authors: Yeo Sara K. , Anderson Ashley A. , Becker Amy B. , Cacciatore Michael A.
Published: May 2020

Humor has been recommended for scientists looking to conduct communication activities despite relatively little empirical evidence demonstrating its effectiveness. Here, we examine the social environment of a joke through a two-condition experimental design that manipulates the presence or absence of audience laughter. Specifically, we examine how humor experienced from viewing a video clip of a science comedian embedded in an online survey can have downstream effects on whether people view comedy as a valid source of scientific information. We found that respondents who perceived more humor in the video clip (i.e. those in the condition with audience laughter) had more positive views about comedy as a valid source of scientific information. Interestingly, this relationship was mediated by perceived expertise, not likability, of the scientist engaging in comedy.
In Vitro Evaluation and Transplantation of Human Corneal Endothelial Cells Cultured on Biocompatible Carriers
Authors: Spinozzi Daniele , Miron Alina , Lie Jessica T. , Rafat Mehrdad , Lagali Neil , Melles Gerrit R.J. , Dhubhghaill Sorcha Ni , Dapena Isabel , Oellerich Silke
Published: May 2020

Corneal transplantation is currently the only effective treatment option for dysfunctional corneal endothelial cells (CEC). In this study, we test in vitro the surgical potential of cultivated human corneal endothelial cells (hCEC) on human anterior lens capsule (HALC), LinkCell™ bioengineered collagen sheets of 20-µm thickness (LK20), and denuded Descemet membrane (dDM) as tissue-engineered grafts for Descemet membrane (DM) endothelial keratoplasty (DMEK) to bypass the problem of donor tissue availability. Primary hCEC cultured on all carriers formed a monolayer of tightly packed cells with a high cell viability rate (96% ± 4%). hCEC on HALC and LK20 showed unremarkable expression of zonula occludens-1 (ZO-1) and Na+/K+-adenosine triphosphatase (ATPase), while Na+/K+-ATPase expression of cells seeded on dDM was mainly cytoplasmic. All hCEC–carrier constructs were evaluated by simulating DMEK surgery in vitro using a human donor cornea without DM mounted on an artificial anterior chamber (AC) and a regular DMEK-graft used as a surgical reference model. During in vitro surgery, hCEC–HALC constructs behaved most similarly to a DMEK-graft during implantation and unfolding, showing good adhesion to the bare stroma. On the other hand, hCEC–LK20 and hCEC–dDM constructs required some additional handling because of challenges related to the surgical procedure, although they were both successfully unfolded and implanted in the artificial AC. The hCEC–dDM constructs showed similar graft adherence as hCEC–HALC constructs, while adherence of hCEC–LK20 constructs was less effective. After the in vitro surgery, the estimated area populated by viable cells on the hCEC–HALC and hCEC–LK20 constructs was ∼83% and ∼67%, respectively. Overall, hCEC–HALC constructs behaved most similarly to a DMEK-graft during in vitro DMEK surgery, while graft adhesion and surgical handling, respectively, are parameters still requiring optimization for hCEC–LK20 and hCEC–dDM constructs.
Dynamic Capabilities? Unleashing Their Dynamics through a Practice Perspective on Organizational Routines
Authors: Wenzel Matthias , Danner-Schröder Anja , Spee A. Paul
Published: May 2020

The current conceptualization of dynamic capabilities entails a paradox, one that hampers the achievement of one of the framework’s main missions: While studies on dynamic capabilities claim to offer explanations of continuous, routine-based organizational change, their prevalent conceptualization of organizational routines is rather undynamic and less prone to change. Thus, we propose to draw on an alternative, practice-based understanding of organizational routines to unravel the “dynamics” of dynamic capabilities. The practice perspective captures and explains the internal dynamics of organizational routines and positions the performance of organizational routines as a source of both organizational stability and change. This perspective offers to deepen our understanding of the dynamics within dynamic capabilities as driver of routine-based organizational change. To foster a research agenda that advances our understanding of dynamic capabilities from a practice perspective on organizational routines, we provide onto-epistemological, theoretical, and methodological implications of such a “dynamic view” of dynamic capabilities.
Expression of TdT in Myoepithelial Cells: Investigation in Breasts, Sweat Glands, and Salivary Lesions Emphasizing the Never-Documented Immunohistochemical Findings
Authors: Zhou Jun , Xu Haimin , Zeng Hong , Ma Hongjun , Yu Jingjing , Liu Xia , Sun Zhulei , Zhou Luting , Zheng Saifang , Wang Xue , Wang Anran , Wang Chaofu
Published: May 2020

Background. The expression of terminal deoxynucleotidyl transferase (TdT) in myoepithelial cells (MECs) within the breast was recently incidentally observed in our routine practice. This study aimed to elucidate the expression of TdT in MECs. Methods. TdT immunostaining was performed on 180 mammary, 89 cutaneous, and 94 salivary tissues or lesions. Other myoepithelial markers, including P63, calponin, and SMA as well as double staining for TdT and calponin, were also evaluated in some cases. Selected lesions with basal or myoid differentiation were also included in the investigation. Results. MECs were positive for TdT in mammary lesions that contained MECs (132/135) but negative when they did not contain MECs (45/45). MECs in sweat glands (24/30) and their neoplastic counterparts, including those in hidradenoma papilliferum (2/9), spiradenoma (6/6), and cutaneous mixed tumor (9/9), showed weak to moderate TdT positivity. MECs were variably immunolabeled for TdT in salivary or salivary gland–type tumors with myoepithelial differentiation (pleomorphic adenoma, 24/25; basal cell adenoma, 6/7; adenoid cystic carcinoma, 7/7; Warthin tumor, 0/6; mucoepidermoid carcinoma, 0/8; acinic cell carcinoma, 0/4), but MECs in normal salivary gland barely stained for TdT (30/32). Conclusions. Our findings indicate that TdT may be eligible as an additional auxiliary immunohistochemical marker as P63, but not a surrogate, to identify the MECs in the breast with limited cross-reactivity, particularly in lesions with a prominent proportion of MECs. Positivity for TdT, along with other relevant markers, in a subset of sweat gland lesions and salivary tumors may contribute to their diagnosis.
Immunophenotype-Genotype Correlations in Clear Cell Sarcoma of Kidney—An Evaluation of Diagnostic Ancillary Studies
Authors: Kenny Colin , Grehan David , Ulas Mevlut , Banga Gloria Badi , Coulomb Aurore , Vokuhl Christian , O'Sullivan Maureen J
Published: May 2020

Introduction

The purpose of this study was to establish a reliable panel of antibodies for immunohistochemical corroboration of a diagnosis of clear cell sarcoma of kidney (CCSK), taking into consideration the various genotypic subsets of CCSK.

Methods

We conducted full genotypic analysis for evidence of YWHAE-NUTM2, BCOR internal tandem duplication (ITD), and BCOR-CCNB3 in 68 archival cases of CCSK and then immunostained all cases for CCND1, TLE1, and BCOR along with 63 control samples representing tumor types that may enter into the differential diagnosis of CCSK, including 7 congenital mesoblastic nephromas, 2 desmoplastic small round cell tumors, 13 malignant rhabdoid tumors, 9 Ewing sarcomas/primitive neuroectodermal tumor, 5 synovial sarcomas, and 27 Wilms' tumors.

Results

Molecular assays showed that 54 CCSKs harbored a BCOR-ITD, 1 case expressed a YWHAE-NUTM2 fusion transcript while none expressed the BCOR-CCNB3 fusion. The remaining 13 CCSKs were designated “triple-negative” based on the molecular findings. CCND1 showed positive immunoreactivity across all subgroups. TLE1 was positive in 94% of cases, including 1 YWHAE-NUTM2 fusion-positive case. Three BCOR-ITD-positive tumors were TLE1-negative. BCOR immunostaining was most variable among subgroups, with triple-negative tumors showing the weakest staining. In all, 10/68 (15%) tumors did not stain for BCOR, of which 4 were triple-negative (4/13 = 31%) and 6 were BCOR-ITD-positive (6/54 = 11%). The single YWHAE-NUTM2-positive tumor showed strong staining for all 3 markers. No single case was negative for all 3 stains; however, 3 cases showed no reactivity for either BCOR or TLE1 of which 1 was triple-negative and 2 BCOR-ITD-positive.

Conclusion

Having completed the first comprehensive evaluation of immunostaining of 68 fully genotyped CCSK tumors, we show herein that there is a rationale for the use of a small panel of antibodies to assist in the diagnosis of CCSK regardless of genotype, and we demonstrate that in combination CCND1, TLE1, and BCOR are compelling markers in aiding CCSK diagnosis.
Do trabecular metal cups achieve better results when compared to hemispherical porous titanium cups in acetabular revision surgery?
Authors: Cruz-Pardos Ana , García-Rey Eduardo , Fernandez-Fernández Ricardo , Ortega-Chamarro José
Published: May 2020

Background:

Trabecular metal (TM) cups were introduced in order to achieve better ingrowth and stability of the cup in acetabular revision surgery. As their use has evolved over time, we have queried whether TM cups would improve results in terms of the rate of aseptic loosening when compared to historical uncemented porous titanium cups used in revision surgery for acetabular bone loss in Hospital La Paz (Madrid, Spain).

Methods:

We retrospectively reviewed 197 acetabular revisions performed between 1991 and 2015. Titanium cups were used in 81 cases and TM cups in 116. The mean follow-up was 8.1 years (range 1–15); 12.0 ± 7.8 for titanium group and 5.4 ± 3.1 for TM group. The most common reason for revision was aseptic loosening. A Kaplan-Meier analysis was used to determine the survival of the cup, with radiological failure and re-revision due to aseptic loosening as the endpoints. Cox multivariate regression analyses were performed to assess different risk factors for failure.

Results:

1 TM cup and 1 titanium cup were re-revised due to aseptic loosening ( p = 0.61). Radiological cup loosening was observed in 4 TM cups and 2 titanium cups ( p = 1.0). At 6 years, the probability of not having radiological cup loosening was 97.4% (95% CI, 93.9–100) for the titanium cups and 95.1% for the TM cups (95% CI, 90.1–99.9) ( p = 0.59). Another 5 cups were re-revised due to dislocation. Hips with a greater Paprosky defect showed a higher risk of loosening ( p < 0.05, hazard risk (HR) 3.04; 95% CI, 0.97–9.54).

Conclusions:

This study shows there was no significant difference in re-revision due to aseptic loosening or radiological loosening between titanium and TM cups in revision surgery for acetabular bone loss. Both types of cups demonstrate excellent results with a low failure rate and minimal complications.
Peritoneal dialysis catheter intraluminal fibrin cast: A complication after prolonged placement. Case series with a review of literature and the management of this complication
Authors: Tan Rebekah , Sieunarine Kishore
Published: May 2020

Peritoneal dialysis is a renal substitutive therapy used in an increasing number of patients with end-stage renal failure as it allows greater freedom to perform daily activities. Peritoneal dialysis catheter obstruction is a significant non-infectious complication of peritoneal dialysis. We describe three cases of peritoneal dialysis catheter obstruction with complete fibrin casts, its surgical management and a review of the literature in management techniques and have proposed an algorithm to guide clinical practise when a complete intraluminal peritoneal dialysis catheter obstruction is suspected.
Analyzing predisposing, precipitating, and perpetuating factors of militancy through declassified interrogation summaries: A case study
Authors: Krishan Aggarwal Neil
Published: May 2020

Researchers and policymakers have supported a public health approach to countering violent extremism throughout the War on Terror. However, barriers to obtaining primary data include concerns from minority groups about stigmatization, the ethics of harming research subjects by exposing them to violent content, and restrictions on researchers from institutions and governments. Textual analyses of declassified documents from government agencies may overcome these barriers. This article contributes a method for analyzing the predisposing, precipitating, and perpetuating factors of terrorism through open source texts. This method is applied to FBI interrogation summaries of Al Qaeda terrorist Umar Farouk Abdulmutallab who attempted an attack aboard an airplane in 2009. This analysis shows that consuming militant content online led him to narrow his social relationships offline to extremists and foster identifications with subjugated Muslims around the world. After deciding to wage militancy, loyalty to Al Qaeda members, swearing allegiance to and obeying group leaders, and interpreting religious texts militantly perpetuated violent activities. Such work can advance empirical work on militant behavior to develop interventions.
From multi-speed to multi-stream? Recognising the motivations, processes and triggers behind party membership
Authors: Power Sam , Dommett Katharine
Published: May 2020

A key question facing scholars of party politics is the journey engaged individuals take to becoming party members. We argue that the existing literature largely outlines one aspect – motivation. In this article, we present an alternative position: that a membership journey is only complete when a motivation, process and trigger are present. We outline this utilising a case study of the Green Party of England and Wales including previously confidential internal party documents, membership figures, elite interviews, focus group research and participant observation to provide a different means to understand membership fluctuations. We present these findings as an exploratory and inductive reinterpretation of existing debates. However, we also suggest that the findings are of interest not just in the case of the Green Party, nor the United Kingdom, but to all those who study party membership.
Mechanical properties of recycled aggregate concrete under multiaxial compression
Authors: Wang Yumei , Deng Zhiheng , Xiao Jianzhuang , Sheng Jun
Published: May 2020

The mechanical properties of recycled aggregate concrete under multiaxial compression were tested by servo-controlled setup (TAWZ-5000/3000). Properties of strength and stress–strain relation were obtained, and the influence factors of stress ratio and recycled coarse aggregate replacement ratio were analyzed. The results show that the strength of recycled aggregate concrete under multiaxial compression is higher than that of under uniaxial state, the stress ratio and recycled coarse aggregate replacement ratio have obvious effect on strength, and the shape of stress–strain curve is also varied with different levels of the two factors. Failure criterion can reflect the strength relation for recycled concrete under multiaxial stress state. Kupfer’s failure criterion is selected to describe strength properties under biaxial stress state, and the failure envelope reflects the energy absorption of different mix series. Based on octahedral stress theory, the tensile and compressive meridians have been proposed to analyze the strength characteristics under triaxial compression, and the theoretical values are well coherent with the test data.
Police spokespersons: A question of organizational representation
Authors: Simpson Rylan , Wetherell Kamali’ilani
Published: May 2020

Police spokespersons exist at the core of organizational representation: they are selected to represent their agencies at all levels of engagement on all public platforms. Given their repeated exposure via traditional and electronic media, perceptions of spokesperson characteristics may impact perceptions of police and police organizations more broadly. Using online search queries of publicly available sources, we collected data for 612 spokespersons from 514 municipal police agencies across the United States. Our analyses reveal that spokespersons are overwhelmingly sworn, White men who are middle-aged and mid-rank. Our analyses also reveal some bivariate relationships between spokesperson characteristics (e.g., gender and employment status) and some variation among characteristics across states (e.g., Texas versus Ohio). By identifying and describing spokesperson characteristics at both national and state levels, we extend historical research regarding police spokespersons, contribute to the scholarly understanding of police representation practices, and theorize the relationships between spokespersons, organizations, and contemporary policing issues.
The right to the virtual city: Rural retreatism in open-world video games
Authors: Denham Jack , Spokes Matthew
Published: May 2020

This article uses Lefebvre’s spatial triad and his concept of The Right to the City to categorise open-world video games as contested virtual spatial experiences, interconnected with the non-virtual spaces in which they are produced and played and replete with the same spatial, capital forces of alienation to be negotiated and maintained. We use qualitative gameplay data ( n = 15), unpacking players’ journeys through Lefebvre’s conceived, lived and perceived spaces, to show, respectively, how open-world games can be (1) fundamentally about space, (2) spaces interconnected with the non-virtual world and (3) disruptive spatial experiences. In utilising The Right to the Virtual City and our players’ tendency to retreat into the wild spaces of our case study game, Red Dead Redemption 2, we evoke the same alienating forces of commodification and capitalism to which Lefebvre spoke, positioning open-world video games as both contested spatial experiences and opportunities to challenge spatialised inequalities.
Cylinder-to-cylinder high-pressure exhaust gas recirculation dispersion effect on opacity and NOx emissions in a diesel automotive engine
Authors: Macián Vicente , Luján José Manuel , Climent Héctor , Miguel-García Julián , Guilain Stéphane , Boubennec Romain
Published: May 2020

The objective of the study is to determine the effect of the high-pressure exhaust gas recirculation dispersion in automotive diesel engines in NO x and smoke emissions in steady engine operation. The investigation quantifies the NO x and smoke emissions as a function of the dispersion of the high-pressure exhaust gas recirculation among cylinders. The experiments are performed on a test bench with a 1.6-L automotive diesel engine. In order to track the high-pressure exhaust gas recirculation dispersion in the intake pipes, a valves system to measure CO2, that is, exhaust gas recirculation rate, was installed pipe to pipe. In addition, a valves device to measure NO x emissions cylinder to cylinder in the exhaust was installed. Moreover, a smoke meter device was installed downstream the turbine, to measure the effect of the high-pressure exhaust gas recirculation dispersion on smoke emissions. Five different engine speeds were studied with different torque levels; thus, the engine map was widely studied, from 1250 to 3000 r/min and between 6 and 20 bar of brake mean effective pressure. The exhaust gas recirculation rate varies between 4% and 25% depending on the operating point. The methodology focused on experimental tools combining traditional measuring devices with a specific valves system, which offers accurate information about species concentration in both the intake and the exhaust manifolds. The study was performed at constant raw NO x emissions to observe the effect of the exhaust gas recirculation dispersion in the opacity and fuel consumption. The study concludes that when the exhaust gas recirculation dispersion is low, the opacity presents reduced values in all operating points. However, above a certain level of exhaust gas recirculation dispersion, the opacity increases dramatically with different slopes depending on the engine running condition. This study allows quantifying the exhaust gas recirculation dispersion threshold. In addition, the exhaust gas recirculation dispersion could contribute to increase the fuel consumption up to 3.5%.
Effects of branch structure of alkylbenzenes on spray auto-ignition of n-decane and alkylbenzenes blends
Authors: Duan Yaozong , Liu Wang , Liang Xin , Han Dong
Published: May 2020

Spray auto-ignition characteristics of the blends of n-decane and several alkylbenzenes were carried out on a heated constant-volume spray combustion chamber. The derived cetane numbers of the fuel blends were determined, and the temperature-dependent ignition delay times and combustion durations were measured across a range of temperatures from 808 to 911 K. The results reveal that blending alkylbenzene to n-decane inhibits fuel spray auto-ignition propensity. For mono-alkylbenzenes, the fuel blend containing toluene has a higher derived cetane number than those with ethylbenzene and n-propylbenzene, but has a lower derived cetane number than the fuel blend containing n-butylbenzene. For those binary fuels containing ethylbenzene, n-propylbenzene and n-butylbenzene, their derived cetane numbers increase with the side alkyl chain length. The derived cetane numbers of the fuel blends with C8H10 isomers follow the trend of n-decane/ o-xylene >  n-decane/ethylbenzene >  n-decane/ m-xylene ∼ n-decane/ p-xylene, given the alkylbenzene blending fraction. For the blends with C9H12 isomers, those containing 1,2,3-trimethylbenzene and 1,3,5-trimethylbenzene have the highest and lowest derived cetane numbers, respectively, while the fuel blends containing 1,2,4-trimethylbenzene, n-propylbenzene and i-propylbenzene have comparatively intermediate derived cetane numbers. The blending effects of alkylbenzenes on ignition delay time are consistent with the observation on fuel derived cetane numbers. Both the number and proximity of substituted methyl groups significantly affect fuel auto-ignition propensity, and the adjacent methyl groups could increase the auto-ignition propensity. The combustion duration for the test fuels, except for n-decane and the n-decane/ n-butylbenzene blend, monotonically decreases with increased temperature. The non-monotonic dependence of combustion duration on temperature, for neat n-decane and the n-decane/ n-butylbenzene blend, may result from the increased diffusive burnt fraction. Finally, the comparison between gas-phase and spray auto-ignition reactivity of the test fuels highlights the contribution of both fuel physics and chemistry in spray auto-ignition.
Experimental approach for the analysis of the flow behaviour in the stator of a real centripetal turbine
Authors: Galindo José , Tiseira Izaguirre Andrés Omar , García-Cuevas Luis Miguel , Hervás Gómez Natalia
Published: May 2020

During normal operation, radial turbines may work in off-design conditions. Off-design conditions may be characterised by very low expansion ratios, very high expansion ratios, very low rotational speeds or very high rotational speeds. All of these cases are difficult to characterise experimentally due to high experimental uncertainties or a lack of capabilities in the system feeding pressurised air to the turbine. Also, there are two- and three-dimensional computational fluid dynamics simulations at these operating points but could not be accurate enough due to high turbulence effects, flow detachment and shock wave generation. With a lack of high-quality data, experimental or computational, to fit the reduced-order turbine models used in zero- and one-dimensional engine simulations, there are large uncertainties associated to their results in off-design conditions. This work develops an experimental facility able to characterise the internal flow of radial turbine stators in terms of pressure and velocity fields at off-design and regular working conditions. The facility consists of an upscaled model of a radial turbine volute and stator fed with air in pressure- and temperature-controlled conditions, so different sensors can be used inside it with the least amount of flow disturbance. The different restrictions considered in the design of the upscaled model are presented, and their effects in the final experimental apparatus capabilities are discussed. A preliminary comparison between computational fluid dynamics simulations and experimental data shows encouraging results.
Numerical study of purging of a gasoline direct injection nozzle at the end of injection
Authors: Mouvanal Sandeep , Burkhardt Axel , Bakshi Shamit , Chatterjee Dhiman
Published: May 2020

In gasoline direct injection engines, fuel injector nozzle is one of the vital components that determine the efficiency of fuel atomization which controls combustion and emission. There is an increased focus on developing better nozzles by studying the internal flow behavior especially during the needle transient phase and at the end of injection phase. Multiphase flow characteristics involving cavitation and hydraulic flip are observed inside the nozzle during its operation. At the end of injection, fuel inside the nozzle sac and nozzle holes is purged with the gas from the engine cylinder. The efficiency of this purging process is critical to prevent the carbon deposit formation on the wall of nozzle holes and on the surface of the nozzle tip. In this article, a numerical method is presented to predict the internal nozzle flow during the needle movement and during the end of injection to predict the purging capacity of a gasoline direct injection nozzle. Needle motion is accomplished using a moving mesh method via a user-defined function. The numerical model is compared with the X-ray measurements from the literature. Based on the validated model, the study is extended to analyze various parameters like injection pressure, nozzle hole location, number of nozzle holes and the inlet rounding of the nozzle hole which affects the effectiveness of nozzle purging. Fuel wetting at the nozzle tip after the end of injection is also numerically modeled to evaluate the thickness profile of the thin liquid film.
Two-Year Outcomes of Orbital Atherectomy Combined With Drug-Coated Balloon Angioplasty for Treatment of Heavily Calcified Femoropopliteal Lesions
Authors: Kokkinidis Damianos G. , Jawaid Omar , Cantu David , Martinsen Brad J. , Igyarto Zsuzsanna , Valle Javier A. , Waldo Stephen W. , Armstrong Ehrin J.
Published: May 2020

Purpose: To examine whether the combination of orbital atherectomy (OA) and drug-coated balloons (DCB) can lead to superior procedural and 2-year outcomes compared with DCB only in heavily calcified femoropopliteal (FP) lesions. Materials and Methods: A retrospective chart review was conducted to identify patients treated with DCB only or OA+DCB for de novo FP lesions at a single center over a 4-year period (2014–2017). In the observation period, 113 patients met the inclusion criteria: 63 treated with DCB only (mean age 69.0±8.6 years; 62 men) vs 50 treated with OA+DCB (mean age 70.3±7.1 years; 48 men). The OA+DCB group had higher calcification rates (78% with severe calcification vs 37% in the DCB only group). Propensity score matching (PSM) was used to adjust for baseline differences between the 2 groups. Cox regression analysis was used to compare the follow-up outcomes between lesions treated with OA+DCB vs DCB only. Results: No difference in procedural complications or success was found. After PSM adjustment, the OA+DCB group was associated with lower bailout stenting rates (39.4% vs 66.7% in the DCB only group; p=0.026). The 2 groups had similar long-term outcomes, although the OA+DCB arm had a trend toward reduced TLR rates that did not reach statistical significance. The Kaplan-Meier estimates for 2-year freedom from TLR were 76.1% for the OA+DCB group vs 55.5% for the DCB only group (p=0.109). Conclusion: OA+DCB is a safe and effective combination for the treatment of calcified FP lesions. The combined therapy decreased the bailout stenting rates in the adjusted analysis. Larger cohorts and randomized trials are needed to examine OA efficacy in FP lesions.
Mutations in MC4R facilitate the angiogenic activity in patients with orbital venous malformation
Authors: Huang Xiao-Ming , Yang Wan-Chen , Liu Yang , Tang Dong-Run , Wu Tong , Sun Feng-Yuan
Published: May 2020

Orbital venous malformation results from the aberrant angiogenesis in the orbit; however, the detailed molecular mechanism is still not clear. In this study, tissue samples from 27 patients with orbital venous malformation were collected and subjected to whole exome sequencing. Melanocortin 4 receptor was the gene with highest incidence (7/27) of mutation identified in this series. A total of four types of mutations were found in the coding region and the 5ʹ-untranslated region of melanocortin 4 receptor. All these mutations resulted in the upregulation of melanocortin 4 receptor expression. In vitro assays using human umbilical vein endothelial cells demonstrated that the endothelial properties including cell proliferation, cell cycle, cell migration, and tube formation are positively correlated with the expression level of melanocortin 4 receptor. Melanocortin 4 receptor mutations resulted in increased cAMP production in a cell-based assay. By RNA sequencing technique, melanocortin 4 receptor was found to modulate the downstream genes of PI3K/AKT/mTOR pathway, including p21, cyclin B1, ITGA10, and ITGA11, which are known to regulate the endothelial properties. These data demonstrated that mutations in melanocortin 4 receptor modulate the downstream signaling pathway, facilitate the angiogenic activity of endothelial cells, and therefore is one potential mechanism of orbital venous malformation pathogenesis.

Impact statement

The detailed molecular mechanism of orbital venous malformation (OVM) is still not clear. Using whole exome sequencing, 4 types of melanocortin 4 receptor (MC4R) mutation were detected in 7 of 27 patients with OVM, and all types of MC4R mutations resulted in the upregulation of MC4R expression. In vitro study indicated that MC4R has impacts on the proliferation, cell cycle, migration, and tube formation of the endothelial cells. Moreover, MC4R mutations altered the downstream signaling, including cAMP concentration and the expression levels of several PI3K/AKT/mTOR downstream genes, including p21, cyclin B1, ITGA10, and ITGA11. MC4R mutations may lead to the pathogenesis of OVM through modulating the downstream signaling to alter the angiogenic activity of endothelial cells.
Unraveling the Bidirectional Relationship Between Bullying Victimization and Perpetration: A Test of Mechanisms From Opportunity and General Strain Theories
Authors: Walters Glenn D.
Published: May 2020

This study tested two theories designed to explain the bullying perpetration–victimization relationship. Peer delinquency was hypothesized to mediate the pathway from bullying perpetration to victimization, in line with opportunity, lifestyle, and routine activities theories, and anger was held to mediate the pathway from bullying victimization to perpetration as set forth in general strain theory. These pathways were tested in a sample of 3,411 youth (1,728 boys, 1,683 girls) from the Longitudinal Study of Australian Children. A causal mediation analysis performed on three nonoverlapping waves of data, in which prior levels of each predicted variable were controlled, uncovered support for peer delinquency as a mediator of the perpetration–victimization pathway but failed to identify anger as a mediator of the victimization–perpetration pathway. Additional research is required to identify a mediator for the victimization–perpetration pathway and determine whether variables other than peer delinquency mediate the perpetration–victimization pathway.
Brain Activation Imaging in Emotional Decision Making and Mental Health: A Review—Part 2
Authors: Collura Thomas F. , Bonnstetter Ronald J.
Published: May 2020

In this report, we integrate the principles described in part 1 and describe an operational model for emotional decision making that incorporates brain activation data along with subjective experience correlates. This model takes the form of a state machine that carries out transitions between a finite set of 16 possible states of emotional and decision-making response. By considering a 4 × 4 grid of possible states based on left and right activation, in primary (sensation) and secondary (perception/comprehension) response, the range of responses is completely specified. The transition probabilities within this repertoire of possible response states can be used to characterize an individual (or any system) in terms of its likelihood to respond in a particular fashion. The possible value of this model in psychiatry, psychology, and counseling is introduced and discussed.
Specialist role coaching and skill training periodisation: A football goalkeeping case study
Authors: Otte Fabian W , Davids Keith , Millar Sarah-Kate , Klatt Stefanie
Published: May 2020

In sports like association football, professional teams are increasingly devoting resources to the role-based development of individual athletes and sub-groups. By employing ‘specialist coaches’ into athlete-support structures, clubs aim to facilitate individualised athlete training programs to enhance performance preparation as well as skill learning and talent development. Here, we discuss how contemporary pedagogical training approaches, like Nonlinear Pedagogy and the Constraints-Led approach, can enhance effectiveness of specialist role-based athlete development programs to facilitate performance functionality. We argue the need for a model of specialist role-based coaching practice in high performance sports organisations, based on a unified theoretical rationale, such as ecological dynamics. To exemplify the nature of specialist role-based coaching, a case study addresses how Nonlinear Pedagogy and Constraints-Led approach are being used for training professional football goalkeepers in an U23 years age group. Integrating key concepts from ecological dynamics, allied to principles of Nonlinear Pedagogy and the Constraints-Led approach, common skill training principles for specialist role coaches are highlighted. These illustrate the use of the recently introduced ‘Periodization of Skill Training’ framework for specialist role coaching, practically exemplifying a way to harness opportunities for performance enhancement and individualised talent development in the football goalkeeping context.
Term circulation and conceptual instability in the mediation of science: Binary framing of the notions of biological versus chemical pesticides
Authors: Ledouble Hélène
Published: May 2020

This article explores the influence of textual structures on the acquisition of knowledge in popularization discourses related to biopesticides. Following a terminological insight into the linguistic and cognitive complexities of the notion, we proceed to a semantic analysis of press articles in major Anglo-Saxon newspapers, focusing on the explanation strategies used by the media to simplify their presentation. We show that in the mediation process, biopesticides (and co-referent terms) are systematically described as being environmentally friendly, and opposed to chemical pesticides, consistently shown to be detrimental to the environment. We hypothesize that this simplistic binary framing is exploited by journalists as it is easy to understand in a context of agroecological transition and commonly shared distrust for chemical pesticides. In that respect, it proves to be adequate for purposes of explanation and simplification. However, by outlining this discursive process based on duality, we aim to draw attention to the potential misconceptions of plant protection issues in general, and biopesticides in particular. We ultimately demonstrate that when adopting other perspectives (scientific, ontological or ethical), this dual framing proves to be inadequate for the construction of knowledge by any non-expert press reader.