bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of low-dose CT combined with model-based iterative reconstruction algorithm in oncologic patients during follow-up: dose reduction and image quality
Authors: Ippolito Davide , Maino Cesare , Pecorelli Anna , Salemi Ilaria , Gandola Davide , Riva Luca , Talei Franzesi Cammillo , Sironi Sandro 
Published: July 2021

Objectives: To compare image quality and radiation dose of CT images reconstructed with model-based iterative reconstruction (MBIR) and hybrid-iterative (HIR) algorithm in oncologic patients. Methods: 125 oncologic patients underwent both contrast-enhanced low- (100 kV), and standard (120 kV) dose CT, were enrolled. Image quality was assessed by using a 4-point Likert scale. CT attenuation values, expressed in Hounsfield unit (HU), were recorded within a regions of interest (ROI) of liver, spleen, paraspinal muscle, aortic lumen, and subcutaneous fat tissue. Image noise, expressed as standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated. Radiation dose were analyzed. Paired Student’s t-test was used to compare all continuous variables. Results: The overall median score assessed as image quality for CT images with the MBIR algorithm was significantly higher in comparison with HIR [4 (range 3–4) vs 3 (3-4), p = 0.017]. CT attenuation values and SD were significantly higher and lower, respectively, in all anatomic districts in images reconstructed with MBIR in comparison with HIR ones (all p < 0.001). SNR and CNR values were higher in CT images reconstructed with MBIR, reaching a significant difference in all districts (all p < 0.001). Radiation dose were significantly lower in the MBIR group compared with the HIR group (p < 0.001). Conclusions: MBIR combined with low-kV setting allows an important dose reduction in whole-body CT imaging, reaching a better image quality both qualitatively and quantitatively. Advances in knowledge: MBIR with low-dose approach allows a reduction of dose exposure, maintaining high image quality, especially in patients which deserve a longlasting follow-up.
Ankle fractures in children
Authors: Cancino Benjamín , Sepúlveda Matías , Birrer Estefanía 
Published: July 2021

Ankle fractures are common in children, and they have specific implications in that patient population due to frequent involvement of the physis in a bone that has growth potential and unique biomechanical properties. Characteristic patterns are typically evident in relation to the state of osseous development of the segment, and to an extent these are age-dependent. In a specific type known as transitional fractures – which occur in children who are progressing to a mature skeleton –a partial physeal closure is evident, which produces multiplanar fracture patterns. Computed tomography should be routine in injuries with joint involvement, both to assess the level of displacement and to facilitate informed surgical planning. The therapeutic objectives should be to achieve an adequate functional axis of the ankle without articular gaps, and to protect the physis in order to avoid growth alterations. Conservative management can be utilized for non-displaced fractures in conjunction with strict radiological monitoring, but surgery should be considered for fractures involving substantial physeal or joint displacement, in order to achieve the therapeutic goals. Cite this article: EFORT Open Rev 2021;6:593-606. DOI: 10.1302/2058-5241.6.200042
The role of the iliofemoral ligament as a stabilizer of the hip joint
Authors: D’Ambrosi Riccardo , Ursino Nicola , Messina Carmelo , Della Rocca Federico , Hirschmann Michael Tobias 
Published: July 2021

The purpose of this systematic literature review is to analyse the role of the iliofemoral ligament (ILFL) as a hip joint stabilizer in the current literature. A total of 26 articles were included in the review. The ILFL is the largest hip ligament consisting of two distinct arms and is highly variable, both in its location and overall size, and plays a primary role in hip stability; in the case of hip dislocation, the iliofemoral ligament tear does not heal, resulting in a persistent anterior capsule defect. Clinically, the ILFL is felt to limit external rotation in flexion and both internal and external rotation in extension. The abduction–hyperextension–external rotation (AB-HEER) test is overall the most accurate test to detect ILFL lesions. Injuries of the ILFL could be iatrogenic or a consequence of traumatic hip instability, and can be accurately studied with magnetic resonance imaging. Different arthroscopic and open techniques have been described in order to preserve the ILFL during surgery and, in case of lesions, several procedures with good to excellent results have been reported in the existing literature. The current systematic review, focusing only on the ILFL of the hip, summarizes the existing knowledge on anatomy, imaging and function and contributes to the further understanding of the ILFL, confirming its key role in anterior hip stability. Future studies will have to develop clinical tests to evaluate the functionality and stability of the ILFL. Cite this article: EFORT Open Rev 2021;6:545-555. DOI: 10.1302/2058-5241.6.200112
Post-traumatic myositis ossificans: a benign lesion that simulates malignant bone and soft tissue tumours
Authors: Savvidou Olga , Papakonstantinou Olympia , Lakiotaki Eleftheria , Melissaridou Dimitra , Korkolopoulou Pinelopi , Papagelopoulos Panayiotis J. 
Published: July 2021

Myositis ossificans (MO) is a benign bone formation in an extra-skeletal location. The most common subtype of MO, the post-traumatic, usually develops in young males after a traumatic event or sports injury. MO may simulate malignant bone lesions such as extra-skeletal or surface osteosarcomas, or soft tissue sarcomas such as synovial sarcoma or undifferentiated pleomorphic sarcoma. In the early phase the diagnosis of MO is challenging because imaging and histopathological findings may be non-characteristic. Detailed medical history as well as clinical examination, follow-up imaging studies and histological assessment are crucial for a proper diagnosis. Early and accurate differential diagnosis between MO and malignant soft tissue and bone tumours is important to maximize. Cite this article: EFORT Open Rev 2021;6:572-583. DOI: 10.1302/2058-5241.6.210002
Unattainable equipoise in randomized controlled trials
Authors: Phelps Emma Elizabeth , Tutton Elizabeth , Costa Matthew , Hing Caroline ,   On behalf of the STIFF-F research collaborators
Published: July 2021

Aims To explore staff experiences of a multicentre pilot randomized controlled trial (RCT) comparing intramedullary nails and circular frame external fixation for segmental tibial fractures. Methods A purposeful sample of 19 staff (nine surgeons) involved in the study participated in an interview. Interviews explored participants’ experience and views of the study and the treatments. The interviews drew on phenomenology, were face-to-face or by telephone, and were analyzed using thematic analysis. Results The findings identify that for the treatment of segmental tibial fractures equipoise was a theoretical ideal that was most likely unattainable in clinical practice. This was conveyed through three themes: the ambiguity of equipoise, where multiple definitions of equipoise and a belief in community equipoise were evident; an illusion of equipoise, created by strong treatment preferences and variation in collective surgical skills; and treating the whole patient, where the complexity and severity of the injury required a patient-centred approach and doing the best for the individual patient took priority over trial recruitment. Conclusion Equipoise can be unattainable for rare injuries such as segmental tibial fractures, where there are substantially different surgical treatments requiring specific expertise, high levels of complexity, and a concern for poor outcomes. Surgeons are familiar with community equipoise. However, a shared understanding of factors that limit the feasibility of RCTs may identify instances where community equipoise is unlikely to translate into practice. Cite this article: Bone Jt Open 2021;2(7):486–492.
Hip implants can restore anatomical and medialized rotation centres in most cases
Authors: Scheerlinck Thierry , De Winter Elien , Sas Amelie , Kolk Sjoerd , Van Gompel Gert , Vandemeulebroucke Jef 
Published: July 2021

Aims Hip arthroplasty does not always restore normal anatomy. This is due to inaccurate surgery or lack of stem sizes. We evaluated the aptitude of four total hip arthroplasty systems to restore an anatomical and medialized hip rotation centre. Methods Using 3D templating software in 49 CT scans of non-deformed femora, we virtually implanted: 1) small uncemented calcar-guided stems with two offset options (Optimys, Mathys), 2) uncemented straight stems with two offset options (Summit, DePuy Synthes), 3) cemented undersized stems (Exeter philosophy) with three offset options (CPT, ZimmerBiomet), and 4) cemented line-to-line stems (Kerboul philosophy) with proportional offsets (Centris, Mathys). We measured the distance between the templated and the anatomical and 5 mm medialized hip rotation centre. Results Both rotation centres could be restored within 5 mm in 94% and 92% of cases, respectively. The cemented undersized stem performed best, combining freedom of stem positioning and a large offset range. The uncemented straight stem performed well because of its large and well-chosen offset range, and despite the need for cortical bone contact limiting stem positioning. The cemented line-to-line stem performed less well due to a small range of sizes and offsets. The uncemented calcar-guided stem performed worst, despite 24 sizes and a large and well-chosen offset range. This was attributed to the calcar curvature restricting the stem insertion depth along the femoral axis. Conclusion In the majority of non-deformed femora, leg length, offset, and anteversion can be restored accurately with non-modular stems during 3D templating. Failure to restore hip biomechanics is mostly due to surgical inaccuracy. Small calcar guided stems offer no advantage to restore hip biomechanics compared to more traditional designs. Cite this article: Bone Jt Open 2021;2(7):476–485.
32  Gbps heterogeneously integrated quantum dot waveguide avalanche photodiodes on silicon
Authors: Tossoun Bassem , Kurczveil Geza , Srinivasan Sudharsanan , Descos Antoine , Liang Di , Beausoleil Raymond G. 
Published: July 2021

We report a heterogeneous GaAs-based quantum dot (QD) avalanche photodiode (APD) on silicon with an ultralow dark current of 10 pA at

−

1

V

, 3 dB bandwidth of 20 GHz and record gain-bandwidth product (GBP) of 585 GHz. Furthermore, open eye diagrams up to 32 Gb/s are demonstrated at 1310 nm. The k-factor has been measured for these devices to be as low as 0.14. A polarization dependence on gain and bandwidth has been observed and investigated. This shows the potential to integrate a high-speed receiver in a wavelength division multiplexing (WDM) system on a QD-based silicon photonics platform.
Sodium channel activation underlies transfluthrin repellency in Aedes aegypti
Authors: Andreazza Felipe , Valbon Wilson R. , Wang Qiang , Liu Feng , Xu Peng , Bandason Elizabeth , Chen Mengli , Wu Shaoying , Smith Leticia B. , Scott Jeffrey G. , Jiang Youfa , Jiang Dingxin , Zhang Aijun , Oliveira Eugenio E. , Dong Ke 
Published: July 2021

Background
Volatile pyrethroid insecticides, such as transfluthrin, have received increasing attention for their potent repellent activities in recent years for controlling human disease vectors. It has been long understood that pyrethroids kill insects by promoting activation and inhibiting inactivation of voltage-gated sodium channels. However, the mechanism of pyrethroid repellency remains poorly understood and controversial.

Methodology/Principal findings
Here, we show that transfluthrin repels Aedes aegypti in a hand-in-cage assay at nonlethal concentrations as low as 1 ppm. Contrary to a previous report, transfluthrin does not elicit any electroantennogram (EAG) responses, indicating that it does not activate olfactory receptor neurons (ORNs). The 1S-cis isomer of transfluthrin, which does not activate sodium channels, does not elicit repellency. Mutations in the sodium channel gene that reduce the potency of transfluthrin on sodium channels decrease transfluthrin repellency but do not affect repellency by DEET. Furthermore, transfluthrin enhances DEET repellency.

Conclusions/Significance
These results provide a surprising example that sodium channel activation alone is sufficient to potently repel mosquitoes. Our findings of sodium channel activation as the principal mechanism of transfluthrin repellency and potentiation of DEET repellency have broad implications in future development of a new generation of dual-target repellent formulations to more effectively repel a variety of human disease vectors.
Clinical and economic impact of universal varicella vaccination in Norway: A modeling study
Authors: Pawaskar Manjiri , Burgess Colleen , Pillsbury Mathew , Wisløff Torbjørn , Flem Elmira 
Published: July 2021

BackgroundNorway has not implemented universal varicella vaccination, despite the considerable clinical and economic burden of varicella disease.MethodsAn existing dynamic transmission model of varicella infection was calibrated to age-specific seroprevalence rates in Norway. Six two-dose vaccination strategies were considered, consisting of combinations of two formulations each of a monovalent varicella vaccine (Varivax®or Varilrix®) and a quadrivalent vaccine against measles-mumps-rubella-varicella (ProQuad®or PriorixTetra®), with the first dose given with a monovalent vaccine at age 15 months, and the second dose with either a monovalent or quadrivalent vaccine at either 18 months, 7 or 11 years. Costs were considered from the perspectives of both the health care system and society. Quality-adjusted life-years saved and incremental cost-effectiveness ratios relative to no vaccination were calculated. A one-way sensitivity analysis was conducted to assess the impact of vaccine efficacy, price, the costs of a lost workday and of inpatient and outpatient care, vaccination coverage, and discount rate.ResultsIn the absence of varicella vaccination, the annual incidence of natural varicella is estimated to be 1,359 per 100,000 population, and the cumulative numbers of varicella outpatient cases, hospitalizations, and deaths over 50 years are projected to be 1.81 million, 10,161, and 61, respectively. Universal varicella vaccination is projected to reduce the natural varicella incidence rate to 48–59 per 100,000 population, depending on the vaccination strategy, and to reduce varicella outpatient cases, hospitalizations, and deaths by 75–85%, 67–79%, and 75–79%, respectively. All strategies were cost-saving, with the most cost-saving as two doses of Varivax®at 15 months and 7 years (payer perspective) and two doses of Varivax®at 15 months and 18 months (societal perspective).ConclusionsAll modeled two-dose varicella vaccination strategies are projected to lead to substantial reductions in varicella disease and to be cost saving compared to no vaccination in Norway.
Electronic media use and symptoms of depression among adolescents in Norway
Authors: Kleppang Annette Løvheim , Steigen Anne Mari , Ma Li , Søberg Finbråten Hanne , Hagquist Curt 
Published: July 2021

Background
The purpose of this study was to examine the association between electronic media use, including use of social media and gaming, and symptoms of depression, and whether gender or having friends moderated these associations.

Methods
This study was based on self-reported cross-sectional data from the Ungdata survey, conducted in 2018 by the Norwegian Social Research (NOVA) Institute in cooperation with seven regional drug and alcohol competence centres. The target group comprised 12,353 15–16 years old adolescents. Binominal logistic regression was used to analyse the association between electronic media use and symptoms of depression.

Results
The odds of having symptoms of depression were higher for those who used social media more than 3 hours per day (OR: 1.60, 95% CI: 1.43–1.80), compared to those who used social media 3 hours or less per day. Additionally, the odds of having symptoms of depression was higher for those who used more than 3 hours on gaming per day (OR: 1.57, 95% CI: 1.36–1.80), compared to those who used 3 hours and less on gaming per day after adjustment for potential confounders. There were no interaction effects between social media and gaming use with symptoms of depression. Neither were the associations between social media use and gaming with symptoms of depression moderated by gender or having friends.

Conclusions
The odds of having symptoms of depression were significantly higher for adolescents with a more frequent use of electronic media.
Oxygen systems and quality of care for children with pneumonia, malaria and diarrhoea: Analysis of a stepped-wedge trial in Nigeria
Authors: Graham Hamish R. , Maher Jaclyn , Bakare Ayobami A. , Nguyen Cattram D. , Ayede Adejumoke I. , Oyewole Oladapo B. , Gray Amy , Izadnegahdar Rasa , Duke Trevor , Falade Adegoke G. 
Published: July 2021

Objectives
To evaluate the effect of improved hospital oxygen systems on quality of care (QOC) for children with severe pneumonia, severe malaria, and diarrhoea with severe dehydration.

Design
Stepped-wedge cluster randomised trial (unblinded), randomised at hospital-level.

Setting
12 hospitals in south-west Nigeria.

Participants
7,141 children (aged 28 days to 14 years) admitted with severe pneumonia, severe malaria or diarrhoea with severe dehydration between January 2014 and October 2017.

Interventions
Phase 1 (pulse oximetry) introduced pulse oximetry for all admitted children. Phase 2 (full oxygen system) (i) standardised oxygen equipment package, (ii) clinical education and support, (iii) technical training and support, and (iv) infrastructure and systems support.

Outcome measures
We used quantitative QOC scores evaluating assessment, diagnosis, treatment, and monitoring practices against World Health Organization and Nigerian standards. We evaluated mean differences in QOC scores between study periods (baseline, oximetry, full oxygen system), using mixed-effects linear regression.

Results
7,141 eligible participants; 6,893 (96.5%) had adequate data for analysis. Mean paediatric QOC score (maximum 6) increased from 1.64 to 3.00 (adjusted mean difference 1.39; 95% CI 1.08–1.69, p<0.001) for severe pneumonia and 2.81 to 4.04 (aMD 1.53; 95% CI 1.23–1.83, p<0.001) for severe malaria, comparing the full intervention to baseline, but did not change for diarrhoea with severe dehydration (aMD -0.12; 95% CI -0.46–0.23, p = 0.501). After excluding practices directly related to pulse oximetry and oxygen, we found aMD 0.23 for severe pneumonia (95% CI -0.02–0.48, p = 0.072) and 0.65 for severe malaria (95% CI 0.41–0.89, p<0.001) comparing full intervention to baseline. Sub-analysis showed some improvements (and no deterioration) in care processes not directly related to oxygen or pulse oximetry.

Conclusion
Improvements in hospital oxygen systems were associated with higher QOC scores, attributable to better use of pulse oximetry and oxygen as well as broader improvements in clinical care, with no negative distortions in care practices.

Trial registration
ACTRN12617000341325
Волонтерское участие молодежи в период пандемии: портрет героя сложного времени
Authors: Певная Мария Владимировна , Кульминская Алина Владимировна , Широкова Елизавета Александровна , Шуклина Елена Анатольевна 
Published: July 2021

В статье приводится анализ портретных характеристик регионального молодежного волонтерского сообщества, осуществляющего деятельность в период пандемии COVID-19, определяются особенности ее организации и реализации в условиях риска и неопределенности. Эмпирическое исследование проведено методом анкетирования молодежи Свердловской области от 14 до 24 лет в период с 15 августа по 15 октября 2020 г., N = 1105, тип выборки — квотная, ошибка не более 3,5%. В ходе статистического анализа реализованы процедуры бинарной логистической регрессии с целью оценки вклада факторов (социально-демографических, деятельностных, информационных, самоидентификационных и пр.) в участие добровольцев в акции #МыВместе. На результатах исследования показано, что героями сложного времени стали представители малочисленной просоциально настроенной и политически ориентированной части российской молодежи, ранее включенной в организационные структуры, создаваемые в рамках государственной молодежной политики. Исключенным оказалось молодежное большинство. Гипотеза о расширении социальной базы молодежного волонтерства в период пандемии за счет ресурсов интернет-коммуникации не получила эмпирического подтверждения. Была подтверждена дееспособность инфраструктуры волонтерства в решении социальных проблем в кризисный период только в отношении уже организованной молодежи региона. Ее информационные ресурсы оказались действенными исключительно для опытных, активно участвующих в организованной общественной деятельности молодых добровольцев. Показано, что для ядра организованного волонтерского движения молодежи характерны гибридные модели волонтерства, сочетающие элементы традиционной, советской и демократической модели.
Благодарность. Исследование выполнено при финансовой поддержке РФФИ в рамках научного проекта № 20-011-00471.
Analogy as driving force of language change: a usage-based approach towoanddaclauses in 17th and 18th century German
Authors: Gillmann Melitta 
Published: July 2021

AbstractThis paper presents a case study conducted on 17th and 18th century German corpora, confirming that both attraction and differentiation are important mechanisms of change, which interact with socio-symbolic properties of constructions. The paper looks at the frequencies and semantics ofwo‘where’ clauses at the beginning of the New High German period, which are compared to the frequencies and semantics of the connectorda‘there, since’ in the same period. The study reveals that the subordinating connectorswoanddaoverlapped in their functions and were highly polysemous (or semantically vague), establishing spatial, temporal, causal, conditional, and contrast links between clauses. This suggests that the connectors had become functionally similar by means of mutual attraction; however, they differed in that they belonged to different registers. Over the course of the 18th century, the polysemy ofwoanddaclauses reduced. Being gradually confined to one single meaning, the connectors became less similar. This differentiation occurs because the connectors aligned to distinct high-level schemas in the associative network. The study confirms that analogy is crucial to both attraction and differentiation of functionally overlapping constructions. While attraction involves analogy of specific instances of constructions, differentiation occurs in analogy to high-level abstract constructions in the associative network.
Capturing Transnational Entrepreneurial Opportunities through Dual Identification: Immigrant Entrepreneurs and Transnational Activities
Authors: Abd Hamid Hamizah , Ayob Abu Hanifah , Sidek Farhana , Che Senik Zizah 
Published: July 2021

Abstract
The purpose of this paper is to explore the way immigrant entrepreneurs (IEs) capture transnational opportunities in their home and host countries. Through an identity lens, this study adopts a qualitative approach in examining transnational entrepreneurship activities conducted by IEs from three countries (Indonesia, Pakistan and South Korea [henceforth Korea]) in one host country (Malaysia). The findings indicate that IEs’ home-host country identities enable them to recognize and exploit entrepreneurial opportunities in multiple countries through unique resources difficult to be imitated by competitors in their home and host countries. This paper contributes to the international entrepreneurship literature by introducing an identity-sensitive model of immigrant entrepreneurship in transnational spaces which will be useful for policy and practice concerning trade and migration.