bluuebunny/crossref_metadata_2025 huggingface dataset:
New control approaches to improve contact quality in the conventional spans and overlap section in a high-speed catenary system
Authors: Vesali Farzad , Molatefi Habibollah , Rezvani Mohammad A , Moaveni Bijan , Hecht Markus
Published: January 2019

Continuous and quality contact between the pantograph and the catenary system is one of the major challenges for increasing the speed of electric trains. Compared to other studies, this paper has considered the catenary system as the main system and has assumed the pantograph as an excitation factor. Based on this, a controller has been applied on the contact wire, once at the last span and another time near the contact point of the pantograph. Results were compared with the conventional controllers that exert control force on a collector's head. Based on this, two different objectives were considered for the controller including ‘improvement of contact quality’ and ‘minimisation of the vertical velocity of the overlap point’. For this purpose, a full analytical model of the catenary system was presented and was verified using the relevant standards, and then three types of linear quadratic optimal controllers were added to the model with the two objectives mentioned above. The results of the study show that if the model aims to reduce the overlap point vertical velocity, contact quality will be improved. However, in case it aims to enhance contact quality, the velocity of the overlap point will not necessarily be reduced. Moreover, the contact point controller aiming at reducing the overlap point velocity outperforms other controllers and makes 71% improvement in contact quality in comparison with the no-controller case.
Effects of a sweeping jet actuator on aerodynamic performance in a linear turbine cascade with tip clearance
Authors: Chen Shaowen , Li Weihang , Meng Qinghe , Zhou Zhihua , Wang Songtao
Published: January 2019

Sweeping jet actuator as a fresh attempt has been applied in controlling flow separations and improving aerodynamic performances in a linear turbine cascade with tip clearance. In the present study, the oscillating jet process of sweeping jet actuator in the tip clearance was illustrated and a potential advantage from a system integration perspective was validated by an unsteady numerical study. The excitation frequencies and excitation modes were also investigated for achieving the further understanding of the mechanism of sweeping jet actuator for controlling flow separations. By using sweeping jet actuator, the flow separation near the upper endwall was delayed and the flow loss at the outlet of the cascade was reduced. For the optimal case, the time-averaged total pressure loss decreased by about 11.7% with the jet flow rate of only 0.35% of the inlet flow rate. In addition, it was found that there exists an optimum frequency to achieve the optimum controlling effects on the flow separations. Because of the blockage of tip leakage flow at the local gap by the high-momentum fluid from sweeping jet actuator, the controlling effects on the tip leakage vortex loss were better than that on the passage vortex loss. Through the use of four excitation modes in this study, the total pressure losses at the outlet were all reduced in different degrees. Under the present boundary conditions and working parameters, the unsteady controlling mode of sweeping jet actuator was found to perform much better than the other steady modes.
A study on a new criterion for minimum-energy perfect control in the state-space framework
Authors: Hunek Wojciech P , Krok Marek
Published: January 2019

In this article, an advanced study concerning the energy cost of the perfect control algorithm is provided. An application of different nonunique matrix inverses into perfect control law has resulted in remarkable influence on both control and state signals. Following the newly obtained issues, covering the minimum-energy behavior, a new related criterion is proposed here. Based on deterministic norm we can, in a simple way, estimate the crucial energy performance. Simulation examples made in MATLAB/Simulink environment show the high potential of a new approach considered in the article.
Beyond autonomy and care: Experiences of ambivalent abortion seekers
Authors: Kjelsvik Marianne , Sekse Ragnhild J Tveit , Moi Asgjerd Litleré , Aasen Elin M , Nortvedt Per , Gjengedal Eva
Published: January 2019

Background:

While being prepared for abortions, some women experience decisional ambivalence during their encounters with health personnel at the hospital. Women’s experiences with these encounters have rarely been examined.

Objective:

The objective of this study was to explore ambivalent abortion-seeking women’s experiences of their encounters with health personnel.

Research design:

The data were collected in individual interviews and analysed with dialogical narrative analyses.

Participants and research context:

A total of 13 women (aged 18–36 years), who were uncertain of whether to terminate their pregnancies during the first trimester, were interviewed before and after they made their decisions. The participants were recruited at six Norwegian outpatient clinics.

Ethical considerations:

Approval was granted by the Regional Committee for Medical and Health Research Ethics.

Findings:

The ambivalent pregnant women sought to make autonomous decisions while simultaneously involving their closest confidants and health personnel in the process. The following three types of narratives of women’s experiences with encounters with health personnel were identified: the respected women; the identified women; and the abandoned women.

Discussion:

The findings are discussed in terms of the ambivalent pregnant woman’s autonomous responsibility in considering an abortion and how her autonomy can be enabled or impaired during encounters with health personnel.

Conclusion and implication:

Although the women considered themselves autonomous and responsible for their final decisions, they wished health personnel were involved in their situations. The health personnel contributed by enabling or disabling the possibility of decision-making in accordance with the women’s values. The findings indicate that health personnel who care for women considering abortions must be trained in dialogical competence.
Global Versus Local Consumer Culture: Theory, Measurement, and Future Research Directions
Authors: Steenkamp Jan-Benedict E.M.
Published: January 2019

The last few decades have seen the emergence of global consumer culture (GCC) as an important force in the marketplace. Yet, in recent years, powerful political and economic forces suggest that globalization might be stalling, leading to renewed interest in local consumer culture (LCC). This article provides an overview of where the field of international marketing stands on GCC and LCC, and it presents new empirical insights. It elaborates on the roots of GCC and LCC in consumer culture theory, cultural globalization theory, and acculturation theory. This background information sets the context for an in-depth discussion of how international marketers have operationalized consumer attitudes toward GCC and LCC, and their individual-level and national-cultural correlates. The article addresses behavioral and managerial consequences of GCC and LCC and concludes with areas for future research.
Organizing and Implementing Export Pricing: Performance Effects and Moderating Factors
Authors: Hofer Katharina Maria , Niehoff-Hoeckner Lisa Maria , Totzek Dirk
Published: January 2019

Relatively little is known about pricing in the export business, particularly how to organize and implement export pricing within firms and how these issues affect export performance. Therefore, this study investigates antecedents of export performance, specifically the organizational aspects of export pricing and price adaptation and the moderating role of export market characteristics, including export market turbulence, enforcement of contracts, and corruption ranks of the export market. Using a large-scale survey sample of 295 exporting firms in Austria and Germany and secondary data on the export markets involved, the authors show that both the intensity of internal pricing coordination and price adaptation have a positive effect on export performance. Specifically, in highly turbulent export markets, the intensity of internal pricing coordination contributes to export performance. Furthermore, a high level of horizontal dispersion of pricing authority is advisable in countries in which the enforcement of contracts is difficult.
Domestic Violence and Humanitarian Crises: Evidence from the 2014 Israeli Military Operation in Gaza
Authors: Müller Catherine , Tranchant Jean-Pierre
Published: January 2019

Using qualitative data from 21 group discussions and unique survey data from a representative cross-section of 439 women in the Gaza Strip, we investigate how the Israeli military operation “Protective Edge” in 2014 influenced domestic violence (DV), accounting for risk factors at different levels of the ecological model. We combine our survey data with secondary data on infrastructure destruction across Gaza’s neighborhoods, and use propensity score matching techniques to address endogeneity concerns. Our results show that the military operation increased DV, and that this effect manifests itself at relatively low-levels of destruction. Our analysis suggests that the mechanisms are displacement, a lowered ability of married women to contribute to household decision-making, and reduced social support networks.
Mental illnesses are not an ‘ideal type’ of disability for disability income support: Perceptions of policymakers in Australia and Canada
Authors: Mcallister Ashley
Published: January 2019

Aim: This article aims to explore how policymakers conceptualise a person suitable for disability income support (DIS) and how this compares across two settings – Australia and Canada. Methods: A constructivist grounded theory approach was used; 45 policymakers in Australia and Canada were interviewed between March 2012 and September 2013. All policymakers are or were influential in the design or assessment of DIS. Results: Results found that the policymakers in both jurisdictions define a suitable person as having as an ‘ideal type’ of disability with five features – visibility, diagnostic proof, permanency, recognition as a medical illness and perceived as externally caused. Many of the policymakers described how mental illnesses are not an ‘ideal type’ of disability for DIS by juxtaposing the features of mental illnesses against physical illnesses. As such, mental illnesses were labelled imperfect disabilities and physical illnesses as ‘ideal type’ for DIS. Conclusions: The rise of DIS recipients has divided the once protected ‘deserving’ category of the disabled into more (‘ideal type’ of disability) and less deserving (imperfect disability). Such conceptualisations are important because these categories can influence the allocation of welfare resources.
Educational level and living arrangements are associated with dietary intake of red meat and fruit/vegetables: A Danish cross-sectional study
Authors: Laursen Ulla Bach , Johansen Martin Berg , Joensen Albert Marni , Lau Cathrine Juel , Overvad Kim , Larsen Mogens Lytken
Published: January 2019

Aims: To evaluate the association between education and living arrangements and the intake of fish, red meat and fruit and vegetables. Methods: The study design was cross-sectional and conducted in Denmark in 2013. Participants filled in questionnaires about their educational level and living arrangements (living alone or with others) and dietary intake including fish, red meat, fruit and vegetables. Regression analyses were performed to assess the associations within 85,456 randomly sampled healthy men and women who were at least 25 years old. Results: Length of education was statistically significant and positively associated with the intake of fruit and vegetables and negatively associated with the intake of red meat for both men and women. Men with a high level of education had a 187g/week (95% confidence interval: 199–175g/week) lower intake of red meat and a 109g/day (95% confidence interval: 102–117g/day) higher intake of fruit and vegetables than men with a low level of education. Women with a high level of education had a 175g/week (95% confidence interval: 186–164g/week) lower intake of red meat and a 106g/day (95% confidence interval: 97–114g/day) higher intake of fruit and vegetables than women with a low level of education. Living with others was statistically significant and positively associated with the intake of red meat, and fruit and vegetables. There were no clear associations between education, living arrangements and intake of fish. Conclusions: Men and women with a high educational level ate more fruit and vegetables but less red meat than men and women with a low educational level. Men and women living with others ate more red meat, fruit and vegetables than men and women living alone.
Increased prevalence of pancreaticobiliary maljunction in biliary malignancies
Authors: Hyvärinen I. , Hukkinen M. , Kivisaari R. , Parviainen H. , Nordin A. , Pakarinen M. P.
Published: January 2019

Aim:

The incidence of pancreaticobiliary maljunction is thought to approximate 1:100,000 within Western populations. We aimed to study the significance of pancreaticobiliary maljunction in biliary tract malignancies.

Methods:

Medical records and magnetic resonance cholangiopancreatography images of 252 consecutive patients treated for biliary malignancies during 2005–2016 were reviewed. Patients with other known risk factors for biliary cancers (n = 27) were excluded. A common pancreaticobiliary channel measuring ⩾10 mm outside the duodenal wall was defined as pancreaticobiliary maljunction.

Main Results:

Of the 225 patients, a reliably interpretable preoperative magnetic resonance cholangiopancreatography was available for 73 (32%). Sex (47% vs 57% females) and age at diagnosis (67 vs 66 years) were similar among patients with or without an magnetic resonance cholangiopancreatography (p = ns for both). In magnetic resonance cholangiopancreatography, a pancreaticobiliary maljunction with a median length of 20 mm (range 10–23 mm) was identified in four patients (5.5%, 95% confidence interval 1.6–14), while none had evident accompanying biliary tree dilatation. Pancreaticobiliary maljunction patients were significantly more often females (100% vs 43%, p = 0.043), less likely to have intrahepatic bile duct cancer (0% vs 65%, p = 0.019) while more likely to have gallbladder cancer (75% vs 22%, p = 0.044) compared to the others. Age at diagnosis (66 vs 67 years, p = 0.898), extrahepatic bile duct cancer incidence (25% vs 13%, p = 0.453), and survival status at last follow-up (50% vs 42% alive, p = 1.000) were comparable between the subgroups.

Conclusion:

The prevalence of pancreaticobiliary maljunction is substantially higher in adults with biliary malignancies than one would expect based on its incidence, reinforcing the etiologic role of pancreaticobiliary maljunction especially in females with gallbladder cancer.
Ethics of Adoption and Use of the Linear No-Threshold Model
Authors: Yanovskiy Moshe , Shaki Yair Y. , Socol Yehoshua
Published: January 2019

The linear no-threshold (LNT) model of ionizing radiation–induced cancer assumes that every increment of radiation dose, no matter how small, constitutes an increased cancer risk for humans. Linear no-threshold is presently the most widely applied model for radiation risk assessment. As such, it imposes very heavy burden on the society in both economic and human terms. This model, which was adopted in late 1950s in the wake of massive government investments in science, is controversial and raises important ethical issues. This article identifies 2 issues often missed: scientists usurping the role of policy makers and seeking funding and power. These issues should be considered together with the scientific controversy raging over the validity of the LNT model and the multiple other ethical issues regarding its ongoing use.
Differential regulation of GSK-3β in spinal dorsal horn and in hippocampus mediated by interleukin-1beta contributes to pain hypersensitivity and memory deficits following peripheral nerve injury
Authors: Mai Chun-Lin , Wei Xiao , Gui Wen-Shan , Xu Ya-Nan , Zhang Jun , Lin Zhen-Jia , Tan Zhi , Meng Ying-Tong , Li Yong-Yong , Zhou Li-Jun , Liu Xian-Guo
Published: January 2019

Accumulating evidence shows that inhibition of glycogen synthase kinase-3beta (GSK-3β) ameliorates cognitive impairments caused by a diverse array of diseases. Our previous work showed that spared nerve injury (SNI) that induces neuropathic pain causes short-term memory deficits. Here, we reported that GSK-3β activity was enhanced in hippocampus and reduced in spinal dorsal horn following SNI, and the changes persisted for at least 45 days. Repetitive applications of selective GSK-3β inhibitors (SB216763, 5 mg/kg, intraperitoneally, three times or AR-A014418, 400 ng/kg, intrathecally, seven times) prevented short-term memory deficits but did not affect neuropathic pain induced by SNI. Surprisingly, we found that the repetitive SB216763 or AR-A014418 induced a persistent pain hypersensitivity in sham animals. Mechanistically, both β-catenin and brain-derived neurotrophic factor (BDNF) were upregulated in spinal dorsal horn but downregulated in hippocampus following SNI. Injections of SB216763 prevented the BDNF downregulation in hippocampus but enhanced its upregulation in spinal dorsal horn in SNI rats. In sham rats, SB216763 upregulated both β-catenin and BDNF in spinal dorsal horn but affect neither of them in hippocampus. Finally, intravenous injection of interleukin-1beta that induces pain hypersensitivity and memory deficits mimicked the SNI-induced the differential regulation of GSK-3β/β-catenin/BDNF in spinal dorsal horn and in hippocampus. Accordingly, the prolonged opposite changes of GSK-3β activity in hippocampus and in spinal dorsal horn induced by SNI may contribute to memory deficits and neuropathic pain by differential regulation of BDNF in the two regions. GSK-3β inhibitors that treat cognitive disorders may result in a long-lasting pain hypersensitivity.
Functional and emotional outcomes after transient ischemic attack: A 12-month prospective controlled cohort study
Authors: Sackley Catherine M , Mant Jonathan , McManus Richard J , Humphreys Glyn , Sharp Leslie , Mares Kathryn , Savva George M
Published: January 2019

Background

Symptoms of transient ischemic attack are believed to fully resolve within 24 h of onset. Emerging evidence suggests that there may be prolonged functional and psychological impact, although studies have not been able to robustly identify whether these are the effect of transient ischemic attack or changes usually associated with ageing. We describe trajectories of disability and risk of anxiety and depression among patients seen at transient ischemic attack clinics over 12 months, compared to healthy controls.

Methods

Thirty transient ischemic attack clinics across England participated. A total of 1320 participants were included: 373 diagnosed with transient ischemic attack, 186 with minor stroke, 310 with “possible transient ischemic attack,” 213 with another condition mimicking a transient ischemic attack and 238 controls recruited from primary care providers. Participants completed questionnaires after diagnosis then after 3, 6 and 12 months. Outcomes were the Nottingham Extended Activities of Daily Living Scale and the Hospital Anxiety and Depression Scale. Mixed effects regression was used to estimate group differences and trajectories.

Results

At baseline, confirmed transient ischemic attack patients scored 1.31 HADS-Anxiety points (s.e. = 0.28; p < 0.001) , 0.51 HADS-Depression points (s.e. = 0.26; p = 0.056), and 2.6 NEADL points (s.e. = 1.1; p = 0.020) worse than controls. At 12 months, the deficits were 0.78 (s.e. = 0.30; p = 0.008), 0.97 (s.e. = 0.23; p < 0.001), and 0.96 (s.e. = 0.92; p = 0.294) respectively. Differences among patients diagnosed with minor stroke were like or worse than transient ischemic attack patients.

Conclusions

Transient ischemic attack clinic patients may have functional and emotional impairments compared to the general population irrespective of final diagnosis. The presence of emotional symptoms or risk of developing anxiety or depression did not always fully recover and may increase.
Contemporary prognosis of transient ischemic attack patients: A systematic review and meta-analysis
Authors: Najib Nashwa , Magin Parker , Lasserson Daniel , Quain Debbie , Attia John , Oldmeadow Christopher , Garcia-Esperon Carlos , Levi Christopher
Published: January 2019

Background

Transient ischemic attacks are common and place patients at risk of subsequent stroke. The 2007 EXPRESS and SOS-TIA studies demonstrated the efficacy of rapid treatment initiation. We hypothesized that with these findings having informed subsequent transient ischemic attacks management protocols, transient ischemic attacks prognosis in contemporary (2008 and later) patient cohorts would be more favorable than in historical cohorts.

Methods

A systematic review and meta-analysis of cohort studies and randomized control trial placebo-arms of transient ischemic attack (published 2008–2015). The primary outcome was stroke. Secondary outcomes were mortality, transient ischemic attack, and myocardial infarction. Studies were excluded if the outcome of transient ischemic attack patients was not reported separately. The systematic review included all studies of transient ischemic attack. The meta-analysis excluded studies of restricted transient ischemic attack patient types (e.g. only patients with atrial fibrillation). The pooled cumulative risks of stroke recurrence were estimated from study-specific estimates at 2, 7, 30, and 90 days post-transient ischemic attack, using a multivariate Bayesian model.

Results

We included 47 studies in the systematic review and 40 studies in the meta-analysis. In the systematic review (191,202 patients), stroke at 2 days was reported in 13/47 (27.7%) of studies, at 7 days in 20/47 (42.6%), at 30 days in 12/47 (25.5%), and at 90 days in 33/47 (70.2%). Studies included in the meta-analysis recruited 68,563 patients. The cumulative risk of stroke was 1.2% (95% credible interval (CI) 0.6–2.2), 3.4% (95% CI 2.0–5.5), 5.0% (95% CI 2.9–8.9), and 7.4% (95% CI 4.3–12.4) at 2, 7, 30, and 90 days post-transient ischemic attack, respectively.

Conclusion

In contemporary settings, transient ischemic attack prognosis is more favorable than reported in historical cohorts where a meta-analysis suggests stroke risk of 3.1% at two days.
Charting the development of a field: A systematic review of comparative studies of journalism
Authors: Hanusch Folker , Vos Tim P
Published: January 2019

Comparative studies of journalism have gained considerable currency in recent years, and are often considered to be at the cutting edge of journalism studies. Yet, there has been relatively little systematic examination of the growth of comparative journalism studies or in-depth analysis of the power relations within the field in relation to, for example, trends in authorship or dominant methodologies and paradigms. This article reports the results of a systematic review of comparative studies of journalism published between 2000 and 2015, a key growth period for the field. By examining in detail a population of 441 articles published in 22 key journals, we demonstrate that comparative journalism studies is a dynamic field that has developed considerable structure over time, and outline some key patterns, such as a continuing focus on Western authorship, the study of Western countries and elite media, quantitative methods of analysis and political aspects of journalism.
Religious conversions in forced migration: Comparative cases of Afghans in India and Iranians in Turkey
Authors: Akcapar Sebnem Koser
Published: January 2019

This article examines closely the crucial link between religious conversions of two groups of refugees from Islam to Evangelism by taking up the cases of Afghan and Iranian refugees in India and in Turkey, respectively. India hosts many refugees from different parts of the world despite the absence of international protection laws, whereas Turkey is the country hosting the highest number of refugees since 2015, mainly due to the Syrian conflict. In this article, I first analyze the reasons why Afghan and Iranian refugees decide to change religious group membership from different sects of Islam and become members of the “born-again” evangelical Christian groups operating in South Asia and West Asia. By combining forced migration and religious identity issues in two different settings, I suggest that a combination of contextual and institutional factors explain this religious change and help us understand the sociocultural and political impacts of conversions.
Globalization of redemptive sociality: al-Ahbash and Haqqaniyya transnational Sufi networks in West Asia and Central-Eastern Europe
Authors: Yarosh Oleg
Published: January 2019

This article examines historical connectedness inside West Asia, that is, Levant, and beyond the region, specifically to North Caucasus and Central-Eastern Europe (Germany and Ukraine) maintained through the translocal Sufi communities, that is, Naqshbandiyya-Haqqaniyya and al-Ahbash. The article demonstrates how these two Sufi networks that originated in the 1970s–1980s in Levant and later spread across the globe through migration routes, missionary activities, and conversions are contextualized in the Western sociocultural milieu in terms of discourses, practices, and institutionalization. While dealing with “redemptive sociality” in the Sufi communities as a form of collective solidarity based on allegiance to a charismatic Sufi Shaykh, this article conceptualizes a distinction between the general or founding charisma of silsila represented by its founders and spiritual leaders, and locally constructed charisma negotiated by local Sufi community and its spiritual leader.
Radiation-Induced Rhinitis: Cytological and Olfactory Changes
Authors: Riva Giuseppe , Franco Pierfrancesco , Provenzano Erica , Arcadipane Francesca , Bartoli Claudia , Lava Paolo , Ricardi Umberto , Pecorari Giancarlo
Published: January 2019

Background

Oral mucositis is a well-known adverse event of radiotherapy (RT) for head and neck cancer (HNC). Its nasal counterpart, the radiation-induced rhinitis, is poorly studied and considered in clinical practice.

Objective

The aim of this observational study was to evaluate acute cytological and olfactory alterations during RT and their correlation with RT doses.

Methods

Ten patients who underwent RT for HNC, excluding tumors of the nasal cavities, were evaluated with nasal scraping for cytological examination, Sniffin’ Sticks test for olfactory assessment, and Nasal Obstruction Symptom Evaluation scale. The examinations were performed before (T0), at mid-course (T1), and at the end (T2) of RT. They were repeated 1 and 3 months after RT (T3 and T4). Mean dose (Dmean) and near maximum dose (D2%) to nasal cavities and inferior turbinates were used for correlation analyses.

Results

Radiation-induced rhinitis was present in 70% of patients at T2, and it was still observed in 40% of cases after 3 months. Although olfactory function remained within the normal range at the evaluated times, a significant decrease in odor threshold and discrimination was observed during RT, which returned to baseline levels after RT. Nasal cytology showed a radiation-induced rhinitis with neutrophils and sometimes bacteria. Mucous and squamous cell metaplasia appeared in 10% of patients. Dmean and D2% to inferior turbinates were associated to neutrophilic rhinitis at T2, and D2% to inferior turbinates was correlated to mucous cell metaplasia at T2.

Conclusions

RT for HNC induces acute rhinitis that may persist after the completion of treatment and can affect patient’s quality of life. Nasal cytology can help to choose the best treatment on an individual basis.
Relative effects of regional and global trade on carbon emissions in ECOWAS member countries
Authors: Oyelami Lukman O
Published: January 2019

The effect of trade on environmental quality has always been ambiguous in both developed and developing countries. This has prompted several country- and region-specific studies. It is against this background that this study seeks to investigate the effect of international trade on carbon emissions in the ECOWAS subregion in general and specifically determines the relative effect of regional and global trade on carbon emissions. To achieve this, time series data on trade and carbon emissions from 1970 to 2014 were employed for 14 ECOWAS member countries based on data availability and the data were duly subjected to required econometric tests to prevent spurious analysis. PMG/MG method of panel ARDL was adopted to estimate the relative effect of regional and global trade on carbon emissions and this is based on capability of the method to classify relationship into short-run and long-run and also solve endogenity issues. The results from model estimation show that effect of trade on environmental quality is a long-term phenomenon and basically support the view that trade has negative effect on environmental quality. However, regional trade is less harmful and it can guarantee improved environment quality in the long run. The study therefore recommend that countries in the region should trade more with one another especially in areas where they lack competiveness as this can better guarantee a more sustainable development for the entire subregion.
The Needle-and-Knife Technique: A Safe Technique for Anterolateral Portal Placement in Elbow Arthroscopy
Authors: Thaveepunsan Sutee , Shields Maegan N. , O’Driscoll Shawn W.
Published: January 2019

Background:

Safe and effective portal placement is crucial for successful elbow arthroscopy. Various techniques for anterolateral portal placement in elbow arthroscopy have been described, yet radial nerve injuries are commonly reported.

Purpose:

To report on the technique and safety of anterolateral portal placement by the needle-and-knife method and its clinical applications.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective review was completed of patients who underwent an arthroscopic procedure in the anterior compartment of the elbow and anterolateral portal placement. Patients were evaluated immediately postoperatively and at subsequent visits and were monitored for signs of radial nerve injury.

Results:

A total of 460 patients met the inclusion criteria, of which 309 (67%) underwent the needle-and-knife technique. There was 1 case (0.3%) of temporary radial nerve palsy. For the remaining 151 patients who underwent anterolateral portal placement by other techniques, there were 2 cases of temporary radial nerve palsy (1.3%). There were no cases of the needle-and-knife technique being unsuccessful or abandoned in lieu of a different technique. Use of the needle-and-knife technique increased over time with experience and practice. Initially, contraindications to this technique included impaired view of the lateral side of the anterior compartment of the elbow caused by severe intra-articular scar (65%), extensive synovitis (10%), or large osteophytes or loose bodies (10%). For the remaining patients (15%) who did not have portals placed via the needle-and-knife technique, alternate techniques were used for teaching purposes.

Conclusion:

The needle-and-knife technique is reproducible and easy to perform by a clinician instructed in its use and trained in elbow arthroscopy. Its main advantage is that it permits the surgeon to safely slide the knife along the lateral supracondylar ridge, releasing the scarred capsule and thereby increasing the available space in which to work. Enlarging the working space inside scarred and contracted elbows cannot be accomplished by distending the capsule.
Neutrophils disturb pulmonary microcirculation in sepsis-induced acute lung injury
Authors: Park Inwon , Kim Mingyo , Choe Kibaek , Song Eunjoo , Seo Howon , Hwang Yoonha , Ahn Jinhyo , Lee Seung-Hyo , Lee Jae Hyuk , Jo You Hwan , Kim Kyuseok , Koh Gou Young , Kim Pilhan
Published: January 2019

The lung is highly vulnerable during sepsis, yet its functional deterioration accompanied by disturbances in the pulmonary microcirculation is poorly understood. This study aimed to investigate how the pulmonary microcirculation is distorted in sepsis-induced acute lung injury (ALI) and reveal the underlying cellular pathophysiologic mechanism.

Using a custom-made intravital lung microscopic imaging system in a murine model of sepsis-induced ALI, we achieved direct real-time visualisation of the pulmonary microcirculation and circulating cellsin vivo. We derived the functional capillary ratio (FCR) as a quantitative parameter for assessing the fraction of functional microvasculature in the pulmonary microcirculation and dead space.

We identified that the FCR rapidly decreases in the early stage of sepsis-induced ALI. The intravital imaging revealed that this decrease resulted from the generation of dead space, which was induced by prolonged neutrophil entrapment within the capillaries. We further showed that the neutrophils had an extended sequestration time and an arrest-like dynamic behaviour, both of which triggered neutrophil aggregates inside the capillaries and arterioles. Finally, we found that Mac-1 (CD11b/CD18) was upregulated in the sequestered neutrophils and that a Mac-1 inhibitor restored the FCR and improved hypoxaemia.

Using the intravital lung imaging system, we observed that Mac-1-upregulated neutrophil aggregates led to the generation of dead space in the pulmonary microcirculation that was recovered by a Mac-1 inhibitor in sepsis-induced ALI.
Surgery or radiotherapy for stage I lung cancer? An intention-to-treat analysis
Authors: Spencer Katie L. , Kennedy Martyn P.T. , Lummis Katie L. , Ellames Deborah A.B. , Snee Michael , Brunelli Alessandro , Franks Kevin , Callister Matthew E.J.
Published: January 2019

Introduction

Surgery is the standard of care for early-stage lung cancer, with stereotactic ablative body radiotherapy (SABR) a lower morbidity alternative for patients with limited physiological reserve. Comparisons of outcomes between these treatment options are limited by competing comorbidities and differences in pre-treatment pathological information. This study aims to address these issues by assessing both overall and cancer-specific survival for presumed stage I lung cancer on an intention-to-treat basis.

Methods

This retrospective intention-to-treat analysis identified all patients treated for presumed stage I lung cancer within a single large UK centre. Overall survival, cancer-specific survival, and combined cancer and treatment-related survival were assessed with adjustment for confounding variables using Cox proportional hazards and Fine–Gray competing risks analyses.

Results

468 patients (including 316 surgery and 99 SABR) were included in the study population. Compared with surgery, SABR was associated with inferior overall survival on multivariable Cox modelling (SABR HR 1.84 (95% CI 1.32–2.57)), but there was no difference in cancer-specific survival (SABR HR 1.47 (95% CI 0.80–2.69)) or combined cancer and treatment-related survival (SABR HR 1.27 (95% CI 0.74–2.17)). Combined cancer and treatment-related death was no different between SABR and surgery on Fine–Gray competing risks multivariable modelling (subdistribution hazard 1.03 (95% CI 0.59–1.81)). Non-cancer-related death was significantly higher in SABR than surgery (subdistribution hazard 2.16 (95% CI 1.41–3.32)).

Conclusion

In this analysis, no difference in cancer-specific survival was observed between SABR and surgery. Further work is needed to define predictors of outcome and help inform treatment decisions.
Managing the innovation legitimacy of the sharing economy
Authors: Hwang Jiyoung
Published: January 2019

Sharing economy has become widespread globally as an innovative service business model. However, some of sharing economy’s socially irresponsible practices have led critics to challenge their legitimacy. Drawing upon legitimacy theory, this research evaluates the legitimacy and corporate social responsibility (CSR) of sharing economy. The current stance of sharing economy’s legitimacy is discussed regarding regulations; legal, tax, and labor issues; politics and lobbying behaviors; social inequality; and societal and economic impact, along with its core concept, sharing. This paper further delineates how CSR and CSR communication can help sharing economy firms manage the challenged legitimacy. As one of the first research attempts, the current paper sheds lights on the dark side of sharing economy and the value of CSR to resolve some concerns about its legitimacy.
A chemical-genetics approach to study the role of atypical protein kinase C in Drosophila
Authors: Hannaford Matthew , Loyer Nicolas , Tonelli Francesca , Zoltner Martin , Januschke Jens
Published: January 2019

Studying the function of proteins using genetics in cycling cells is complicated by the fact that there is often a delay between gene inactivation and the timepoint of phenotypic analysis. This is particularly true when studying kinases, that have pleiotropic functions and multiple substrates. Drosophila neuroblasts are rapidly dividing stem cells and an important model system to study cell polarity. Mutations in multiple kinases cause neuroblast polarity defects, but their precise functions at particular time points in the cell cycle are unknown. Here we use chemical genetics and report the generation of an analogue-sensitive (as) allele of Drosophila atypical protein kinase C (aPKC). We demonstrate that the resulting mutant aPKC kinase can be specifically inhibited in vitro and in vivo. Acute inhibition of aPKC during neuroblast polarity establishment abolishes asymmetric localization of Miranda while its inhibition during NB polarity maintenance does not in the time frame of normal mitosis. However, aPKC contributes to sharpen the pattern of Miranda, by keeping it off the apical and lateral cortex after nuclear envelope breakdown.
Yeast-model-based study identified myosin- and calcium-dependent calmodulin signalling as a potential target for drug intervention in chorea-acanthocytosis
Authors: Soczewka Piotr , Kolakowski Damian , Smaczynska-de Rooij Iwona , Rzepnikowska Weronika , Ayscough Kathryn R. , Kaminska Joanna , Zoladek Teresa
Published: January 2019

Chorea-acanthocytosis (ChAc) is a rare neurodegenerative disease associated with mutations in the human VPS13A gene. The mechanism of ChAc pathogenesis is unclear. A simple yeast model was used to investigate the function of the single yeast VSP13 orthologue, Vps13. Vps13, like human VPS13A, is involved in vesicular protein transport, actin cytoskeleton organisation and phospholipid metabolism. A newly identified phenotype of the vps13Δ mutant, sodium dodecyl sulphate (SDS) hypersensitivity, was used to screen a yeast genomic library for multicopy suppressors. A fragment of the MYO3 gene, encoding Myo3-N (the N-terminal part of myosin, a protein involved in the actin cytoskeleton and in endocytosis), was isolated. Myo3-N protein contains a motor head domain and a linker. The linker contains IQ motifs that mediate the binding of calmodulin, a negative regulator of myosin function. Amino acid substitutions that disrupt the interaction of Myo3-N with calmodulin resulted in the loss of vps13Δ suppression. Production of Myo3-N downregulated the activity of calcineurin, a protein phosphatase regulated by calmodulin, and alleviated some defects in early endocytosis events. Importantly, ethylene glycol tetraacetic acid (EGTA), which sequesters calcium and thus downregulates calmodulin and calcineurin, was a potent suppressor of vps13Δ. We propose that Myo3-N acts by sequestering calmodulin, downregulating calcineurin and increasing activity of Myo3, which is involved in endocytosis and, together with Osh2/3 proteins, functions in endoplasmic reticulum-plasma membrane contact sites. These results show that defects associated with vps13Δ could be overcome, and point to a functional connection between Vps13 and calcium signalling as a possible target for chemical intervention in ChAc. Yeast ChAc models may uncover the underlying pathological mechanisms, and may also serve as a platform for drug testing.

This article has an associated First Person interview with the first author of the paper.
TIMP-1 promotes hypermigration of Toxoplasma-infected primary dendritic cells via CD63–ITGB1–FAK signaling
Authors: Ólafsson Einar B. , Ross Emily C. , Varas-Godoy Manuel , Barragan Antonio
Published: January 2019

Tissue inhibitor of metalloproteinases-1 (TIMP-1) exerts pleiotropic effects on cells including conferring metastatic properties to cancer cells. As for metastatic cells, recent paradigms of leukocyte migration attribute important roles to the amoeboid migration mode of dendritic cells (DCs) for rapid locomotion in tissues. However, the role of TIMP-1 in immune cell migration and in the context of infection has not been addressed. We report that, upon challenge with the obligate intracellular parasite Toxoplasma gondii, primary DCs secrete TIMP-1 with implications for their migratory properties. Using a short hairpin RNA (shRNA) gene silencing approach, we demonstrate that secreted TIMP-1 and its ligand CD63 are required for the onset of hypermotility in DCs challenged with T. gondii. Further, gene silencing and antibody blockade of the β1-integrin CD29 (ITGB1) inhibited DC hypermotility, indicating that signal transduction occurred via ITGB1. Finally, gene silencing of the ITGB1-associated focal adhesion kinase (FAK, also known as PTK2), as well as pharmacological antagonism of FAK and associated kinases SRC and PI3K, abrogated hypermotility. The present study identifies a TIMP-1–CD63–ITGB1–FAK signaling axis in primary DCs, which T. gondii hijacks to drive high-speed amoeboid migration of the vehicle cells that facilitate its systemic dissemination.
MRI-based assessment and characterization of epicardial and paracardial fat depots in the context of impaired glucose metabolism and subclinical left-ventricular alterations
Authors: Rado Sophia D , Lorbeer Roberto , Gatidis Sergios , Machann Jürgen , Storz Corinna , Nikolaou Konstantin , Rathmann Wolfgang , Hoffmann Udo , Peters Annette , Bamberg Fabian , Schlett Christopher L
Published: January 2019

Objective:

To analyze the associations between epicardial and paracardial fat and impaired glucose tolerance as well as left ventricular (LV) alterations.

Methods:

400 subjects underwent 3 T MRI and fat depots were delineated in the four chamber-view of the steady-state free precession cine sequence (repetition time: 29.97 ms; echo time 1.46 ms). LV parameters were also derived from MRI. Oral glucose tolerance tests were performed.

Results:

Epi- and paracardial fat was derived in 372 (93%) subjects (220 healthy controls, 100 persons with prediabetes, 52 with diabetes). Epi- and paracardial fat increased from normal glucose tolerance (NGT) to prediabetes and diabetes (7.7 vs 9.2 vs 10.3 cm2 and 14.3 vs 20.3 vs 27.4 cm2, respectively; all p < 0.001). However, the association between impaired glucose metabolism and cardiac fat attenuated after adjustment, mainly confounded by visceral adipose tissue (VAT). 93 subjects (27%) had LV impairment, defined as late gadolinium enhancement, ejection fraction < 55% or LV concentricity index > 1.3 g ml−1 . Mean epicardial fat was higher in subjects with LV impairment (11.0 vs 8.1 cm2, p < 0.001). This association remained independent after adjustment for traditional risk factors and VAT [β: 1.13 (0.22; 2.03), p = 0.02].

Conclusion:

Although epicardial and paracardial fat are increased in prediabetes and diabetes, the association is mostly confounded by VAT. Epicardial fat is independently associated with subclinical LV impairment in subjects without known cardiovascular disease.

Advances in knowledge:

This study contributes to the picture of epicardial fat as a pathogenic local fat depot that is independently associated with MR-derived markers of left ventricular alterations.
IgG4-mediated sclerosing fibroinflammatory disease presenting as inflammatory breast malignancy
Authors: El-Nayir Muram , Subramanian Ash , Ali Zainab , Howlett David
Published: January 2019

IgG4-mediated sclerosing fibroinflammatory disease is a rare systemic disease which has the ability to form masses in multiple organs and may mimic malignancy. In this case we describe a 53-year-old female who presented with clinical and imaging findings in her right breast consistent with inflammatory breast carcinoma and associated right axillary nodal mass. She underwent CT which also uncovered a left thyroid mass and suggested both masses were possibly malignancies. She proceeded to ultrasound-guided core biopsy of each, which showed an appearance characteristic of IgG4-mediated sclerosing fibroinflammatory disease. The patient was treated with steroids with good outcome. This is the first described case of this condition presenting in this way to our knowledge and this diagnosis should be considered in patients with similar presentations.
Spontaneous non-aneurysmal subarachnoid hemorrhage in Takayasu arteritis: a case implicating hyperperfusion and cerebral dysautoregulation
Authors: Joshi Hena , Allen Jason , Qiu Deqiang , Wu Junjie , Nahab Fadi , Law Karen , Hu Ranliang
Published: January 2019

Takayasu arteritis (TA) is a systemic chronic inflammatory large-vessel vasculitis that affects the aorta, its major branches, and the pulmonary arteries. In this report, we describe a case of a young female with TA presenting with spontaneous subarachnoid hemorrhage (SAH), an unusual manifestation of the disease. Magnetic resonance angiography (MRA) of the head and neck demonstrates multifocal carotid and vertebral arterial stenoses, but no aneurysm or vascular malformation to account for SAH. A novel and unexpected finding in this case was increased cerebral perfusion in the right frontotemporal parenchyma and transient abnormally reduced augmentation of flow in response to the cerebral vasodilator acetazolamide. The etiology of SAH thus may be related to hyperperfusion and loss of cerebrovascular autoregulation leading to small vessel damage.