bluuebunny/crossref_metadata_2025 huggingface dataset:
Combining Participatory and Audiovisual Methods with Young Roma “Affected by Mobility”
Authors: Piemontese Stefano
Published: July 2021

The use of audio-visual methods as a source of data for social inquiry has gained momentum, especially in research with migrant children and young people. For many youth scholars, photos and videos are used both as field notebooks and as working tools that can be employed during interviews or in creating personal diaries to unearth feelings and thoughts that otherwise would remain unexplored. However, producing, viewing and examining visual data together also creates the conditions to develop the collaborative potential that is inherent in the relationship between researchers and young participants. Building on a multi-sited ethnography with a group of Romanian Roma adolescents with different mobility experiences, this chapter offers a theoretically-informed empirical account of the failures, negotiations, and opportunities disclosed by the use of participatory video-making in ethnographic research with underprivileged young people “affected by mobility”.
Conclusions: Participating as Power? The Possibilities and Politics of Participation
Authors: Cantat Céline
Published: July 2021

This chapter reflects on the possibilities and challenges of using participatory research methods in the production of critical knowledge about migration – including visual knowledge. It first reflects on dominant regimes of representations and on the consolidation of a visual knowledge-power nexus around migration. Against this background, it discusses whether and under which conditions participatory approaches may enable the production of counter-hegemonic accounts and knowledges, with a particular focus on the way in which participation can challenge the displacement of violence that underpins dominant and exclusionary representations of migration. After thinking through processes of collective knowledge distribution and exploring the possibilities opened up by participatory dissemination practices, the chapter concludes with a call for further theorisation of participation and for the recognition of its relational and contested nature.
The Researcher’s Nightworkshop: A Methodology of Bodily and Cyber-Ethnographic Representations in Migration Studies
Authors: MacQuarie Julius-Cezar
Published: July 2021

Migrants working the night shift (MWNS) have been invisible to the public eye for far too long. The failure to acknowledge the crucial role played by migrants working in the evening and night-time economy of developed societies is difficult to tackle with classical research tools alone. This chapter offers to novice and seasoned migration scholars a threefold methodological strategy to immerse, inhabit and to bring out of the dark a nocturnal landscape that has been invisible to diurnal people. The researcher’s nightworkshop’s innovative approach provides migration scholars with visual-analytical tools to capture the hidden experiences of MWNS. Theoretically, this chapter considers the broad aspects of representation (reel) and reality (real) of migrants in the public space and in migration scholarship. Night workers, the invisible people of the nocturnal city remain so to scholars, due to the impracticalities of doing nocturnal research (MacQuarie, 2019a). Empirically, therefore, the researcher’s nightworkshop’s strategy offers a solution to the puzzle of ‘invisibility’ of night shift workers. But it also reckons with the fact that to make visible the working lives in the realm of the night is a daunting task for scholars. Readers should interpret the notion of visibilisation with caution, using it as a visual metaphor to expose the factors that alter the night-shift workers’ precarious working conditions. This challenge is addressed here, through efforts that bridge the contingent of night workers, their minds and bodies that share the precarious landscape of nightwork with the researcher – alert and awake via the senses and suffering turned into skills.
Migrants’ Mental Maps: Unpacking Inhabitants’ Practical Knowledges in Lisbon
Authors: Buhr Franz
Published: July 2021

A common consequence of sticking to a research topic for a fair amount of time is that it starts colonising your everyday life to a point where you may find yourself asking questions to every new acquaintance as if they were participants in your project. Your friends may become tired of your constant interrogations, but unknown people might simply take you as someone with a peculiar sense of curiosity. I believe this is what recently happened to me when coming back from a conference and decided to call an Uber driver at Lisbon airport. This chapter explores some of the functionalities mental maps offer to migration research. Mental maps (or cognitive maps) have long helped understanding how individuals use and perceive local space. Yet, as a visual method, mental maps may be produced and analysed in distinct ways. This chapter navigates through existing research employing mental maps and argues for an interactive approach to mental map analysis, in which the researcher-participant engagement becomes as fundamental as the actual visualisation produced. Based on fieldwork with migrants in Lisbon, Portugal, the chapter illustrates the methodological potential of mental maps for yielding information about the ways migrants actively mobilise urban resources.
Conclusions: Touching and Being Touched – Experience and Ethical Relations
Authors: Frers Lars
Published: July 2021

Sometimes, research can hit you in the stomach, making you angry and upset, possibly sick. With a bit of luck, this can be fine, as discontentment can be a force that propels you to become active and engage yourself. Sometimes, research can resonate in your heart, making you aware and empathetic. Not much luck is needed in these cases, as this will hopefully also stimulate you to get new ideas, a better understanding or hopefully even give you a better foothold for whatever you do in practice. Most of the time, research just passes you by, not leaving much of an impression. We do know that words can make a difference, that words can touch you. They evoke many different thoughts and emotions. It is not a single word alone that does this, it is the flow and rhythm of a text, how it takes the reader along, cognitively but also in space and time and in an embodied manner. To achieve different effects, we place words differently, we craft sentences that appeal to different senses and sensibilities, we use terms or jargon, we write complex sentences that juxtapose hosts of different qualities, as Michel Serres does in in The Five Senses (2008). We present a clear definition, we unfold arguments or put something to the point. Most of the word work we do, we do on our keyboards, sitting at a desk, in a train carriage or lying on a sofa. Thus, this word work happens remote from the site where our study took place, it is definitely not the same as the field work that we do, it is not the same as the numbers and algorithms that make up our data. But done well, it can still evoke the sense of what happens or happened “out there” in the field, the phenomena that the numbers point to, be they the numbers of people crossing a border or the feeling of someone who is lost or maybe even hunted (Guttorm, 2016).
Correction to: Trauma and Resilience Among Displaced Populations
Authors: Theisen-Womersley Gail
Published: July 2021

∎∎∎
On $$\mathsf {G} $$-isoshtukas over function fields
Authors: Hamacher Paul , Kim Wansu
Published: July 2021

In this paper we classify isogeny classes of global$$\mathsf {G} $$G-shtukas over a smooth projective curve$$C/{\mathbb {F}}_q$$C/Fq(or equivalently$$\sigma $$σ-conjugacy classes in$$\mathsf {G} (\mathsf {F} \otimes _{{\mathbb {F}}_q} \overline{{\mathbb {F}}_q})$$G(F⊗FqFq¯)where$$\mathsf {F} $$Fis the field of rational functions ofC) by two invariants$${\bar{\kappa }},{\bar{\nu }}$$κ¯,ν¯extending previous works of Kottwitz. This result can be applied to study points of moduli spaces of$$\mathsf {G} $$G-shtukas and thus is helpful to calculate their cohomology.
Einsamkeit während der ersten Welle der SARS-CoV-2-Pandemie – Ergebnisse der NAKO-Gesundheitsstudie
Authors: Berger Klaus , Riedel-Heller Steffi , Pabst Alexander , Rietschel Marcella , Richter Dirk ,   NAKO-Konsortium, Lieb Wolfgang , Hermes Anne , Becher Heiko , Obi Nadia , Günther Kathrin , Ahrens Wolfgang , Castell Stefanie , Kemmling Yvonne , Karch André , Legath Nicole , Schmidt Börge , Emmel Carina , Kuß Oliver , Schikowski Tamara , Koch-Gallenkamp Lena , Holleczek Bernd , Damms-Machado Antje , Halina Greiser Karin , Michels Karin B. , Franzke Claus-Werner , Peters Annette , Thierry Sigrid , Fischer Beate , Leitzmann Michael , Löffler Markus , Wirkner Kerstin , Mikolajczyk Rafael , Rujescu Dan , Gastell Sylvia , Schulze Matthias B. , Krist Lilian , Fricke Julia , Jaeschke Lina , Pischon Tobias , Meinke-Franze Claudia , Völzke Henry
Published: July 2021

Hintergrund

Mit Beginn der SARS-CoV-2-Pandemie und der nachfolgenden Maßnahmen zu ihrer Eindämmung im Frühjahr 2020 ist rasch die Frage nach Auswirkungen der Beschränkung sozialer Kontakte auf die psychische Gesundheit der Bevölkerung aufgekommen. Einsamkeit beschreibt eine wahrgenommene Qualität der eigenen Kontakte und Beziehungen zu anderen Menschen. Zahlreiche Studien haben einen Zusammenhang von Einsamkeit mit somatischen und psychischen Erkrankungen aufgezeigt.

Ziel

Auswertung der Häufigkeit von Einsamkeit und ihrer Beziehung zu Angst- und Depressionssymptomen in der ersten Welle der Pandemie im Mai 2020.

Methoden

Zwischen 2014 und 2019 hat die NAKO-Gesundheitsstudie 205.000 Personen im Alter zwischen 20 und 69 Jahren in 18 Studienzentren in Deutschland rekrutiert und untersucht. Die nachfolgende Zweituntersuchung musste aufgrund der Pandemie im Frühjahr 2020 unterbrochen werden. In dieser Zeit wurde ein COVID-19-bezogener Fragebogen entwickelt und an alle Teilnehmenden verschickt. Ausgewertet wurden die 113.928 Fragebögen, die innerhalb der ersten 30 Tage zurückgeschickt wurden. Einsamkeit wurde mit der 3‑Item UCLA Loneliness Scale, Angst und Depression mit den PHQ-9- und GAD-7-Skalen des Patient Health Questionnaire erhoben.

Ergebnisse

Im Mai 2020 nahmen sich 31,7 % der NAKO-Teilnehmenden als einsam wahr. Frauen und junge Menschen waren häufiger als Männer und ältere Personen betroffen. Mit steigender Wahrnehmung von Einsamkeit nahm der Schweregrad von Depressions- und Angstsymptomen stetig zu. Einsame Personen während der Pandemie hatten bereits zur NAKO-Basisuntersuchung mehr depressive und Angstsymptome angegeben als NAKO-Teilnehmende, die sich in der Pandemie nicht einsam fühlten.

Schlussfolgerung

In der NAKO-Gesundheitsstudie zeigte sich während der ersten Phase der Pandemie eine Zunahme von Einsamkeit und ihr deutlicher Zusammenhang mit schlechterer, psychischer Gesundheit.
Klinische Notfallausbildung in der Pädiatrie
Authors: Markel Franziska , Lück Bettina , Dähnert Ingo , Kiess Wieland , Ackermann Benjamin
Published: July 2021

Hintergrund und Fragestellung

Die klinische Notfallausbildung von WeiterbildungsassistentInnen (WBA) ist uneinheitlich. Pädiatrische Reanimationen sind seltener erforderlich als Reanimationen erwachsener Patienten; erstversorgende Teams treffen ad hoc zusammen und stehen initial oft unter der Leitung junger ÄrztInnen. Die Teamzusammenarbeit ist von besonderer Bedeutung für das Überleben und Outcome der PatientInnen.

Ziel der Arbeit

Die subjektive Sicherheit im Notfallmanagement der WBA in sächsischen Kinderkliniken sollte ermittelt werden.

Material und Methoden

Hierzu wurde ein Erhebungsbogen für eine webbasierte Umfrage entwickelt, die folgende Aspekte umfasste: Berufserfahrung, innerhäusliche Ausbildung, Erfahrung und gefühlte Sicherheit im Management von Notfallsituationen.

Ergebnisse

Von geschätzten 230 Pädiatrie-WBA in Sachsen antworteten 66 (ca. 29 %). Es fühlten sich 14 % der WBA gut (3 % sehr gut) für Notfallsituationen ausgebildet, wobei 11 % auch eine (sehr) gute Sicherheit in der Teamleitung von Notfällen angaben. Demgegenüber hatten 42 % bereits eine oder mehrere Reanimationen als TeamleiterInnen erlebt. Von den befragten WBA gaben 42 % an, in den letzten 12 Monaten kein Simulationstraining absolviert zu haben; die Mehrzahl der WBA wünscht sich jedoch mehr Training.

Schlussfolgerung

Die Ergebnisse zeigen, dass sich viele WBA in sächsischen Kinderkliniken im Notfallmanagement unzureichend ausgebildet fühlen. Es besteht eine deutliche Diskrepanz zwischen den tatsächlichen Anforderungen und der innerklinischen Ausbildung.
The application of cytokeratin-18 as a biomarker for drug-induced liver injury
Authors: Korver Samantha , Bowen Joanne , Pearson Kara , Gonzalez Raymond J. , French Neil , Park Kevin , Jenkins Rosalind , Goldring Christopher
Published: July 2021

Drug-induced liver injury (DILI) is a frequent and dangerous adverse effect faced during preclinical and clinical drug therapy. DILI is a leading cause of candidate drug attrition, withdrawal and in clinic, is the primary cause of acute liver failure. Traditional diagnostic markers for DILI include alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP). Yet, these routinely used diagnostic markers have several noteworthy limitations, restricting their sensitivity, specificity and accuracy in diagnosing DILI. Consequently, new biomarkers for DILI need to be identified.

A potential biomarker for DILI is cytokeratin-18 (CK18), an intermediate filament protein highly abundant in hepatocytes and cholangiocytes. Extensively researched in a variety of clinical settings, both full length and cleaved forms of CK18 can diagnose early-stage DILI and provide insight into the mechanism of hepatocellular injury compared to traditionally used diagnostic markers. However, relatively little research has been conducted on CK18 in preclinical models of DILI. In particular, CK18 and its relationship with DILI is yet to be characterised in an in vivo rat model. Such characterization of CK18 and ccCK18 responses may enable their use as translational biomarkers for hepatotoxicity and facilitate management of clinical DILI risk in drug development. The aim of this review is to discuss the application of CK18 as a biomarker for DILI. Specifically, this review will highlight the properties of CK18, summarise clinical research that utilised CK18 to diagnose DILI and examine the current challenges preventing the characterisation of CK18 in an in vivo rat model of DILI.
Assessment of task-based image quality for abdominal CT protocols linked with national diagnostic reference levels
Authors: Viry Anaïs , Aberle Christoph , Lima Thiago , Treier Reto , Schindera Sebastian T. , Verdun Francis R. , Racine Damien
Published: July 2021

Objectives

To assess task-based image quality for two abdominal protocols on various CT scanners. To establish a relationship between diagnostic reference levels (DRLs) and task-based image quality.

Methods

A protocol for the detection of focal liver lesions was used to scan an anthropomorphic abdominal phantom containing 8- and 5-mm low-contrast (20 HU) spheres at five CTDIvollevels (4, 8, 12, 16, and 20 mGy) on 12 CTs. Another phantom with high-contrast calcium targets (200 HU) was scanned at 2, 4, 6, 10, and 15 mGy using a renal stones protocol on the same CTs. To assess the detectability, a channelized Hotelling observer was used for low-contrast targets and a non-prewhitening observer with an eye filter was used for high contrast targets. The area under the ROC curve and signal to noise ratio were used as figures of merit.

Results

For the detection of 8-mm spheres, the image quality reached a high level (mean AUC over all CTs higher than 0.95) at 11 mGy. For the detection of 5-mm spheres, the AUC never reached a high level of image quality. Variability between CTs was found, especially at low dose levels. For the search of renal stones, the AUC was nearly maximal even for the lowest dose level.

Conclusions

Comparable task-based image quality cannot be reached at the same dose level on all CT scanners. This variability implies the need for scanner-specific dose optimization.

Key Points

• There is an image quality variability for subtle low-contrast lesion detection in the clinically used dose range.

• Diagnostic reference levels were linked with task-based image quality metrics.

• There is a need for specific dose optimization for each CT scanner and clinical protocol.
Influence of breathing state on the accuracy of automated patient positioning in thoracic CT using a 3D camera for body contour detection
Authors: Booij Ronald , van Straten Marcel , Wimmer Andreas , Budde Ricardo P. J.
Published: July 2021

Objective

To assess the influence of breathing state on the accuracy of a 3D camera for body contour detection and patient positioning in thoracic CT.

Materials and methods

Patients who underwent CT of the thorax with both an inspiratory and expiratory scan were prospectively included for analysis of differences in the ideal table height at different breathing states. For a subgroup, an ideal table height suggestion based on 3D camera images at both breathing states was available to assess their influence on patient positioning accuracy. Ideal patient positioning was defined as the table height at which the scanner isocenter coincides with the patient’s isocenter.

Results

The mean (SD) difference of the ideal table height between the inspiratory and the expiratory breathing state among the 64 included patients was 10.6 mm (4.5) (p < 0.05). The mean (SD) positioning accuracy, i.e., absolute deviation from the ideal table height, within the subgroup (n = 43) was 4.6 mm (7.0) for inspiratory scans and 7.1 mm (7.7) for expiratory scans (p < 0.05) when using corresponding 3D camera images. The mean (SD) accuracy was 14.7 mm (7.4) (p < 0.05) when using inspiratory camera images on expiratory scans; vice versa, the accuracy was 3.1 mm (9.5) (p < 0.05).

Conclusion

A 3D camera allows for accurate and precise patient positioning if the camera image and the subsequent CT scan are acquired in the same breathing state. It is recommended to perform an expiratory planning image when acquiring a thoracic CT scan in both the inspiratory and expiratory breathing state.

Key Points

• A 3D camera for body contour detection allows for accurate and precise patient positioning if the camera image and the subsequent CT scan are acquired in the same breathing state.

• It is recommended to perform an expiratory planning image when acquiring a thoracic CT scan in both the inspiratory and expiratory breathing state.
Nonnegative and Strictly Positive Linearization of Jacobi and Generalized Chebyshev Polynomials
Authors: Kahler Stefan
Published: July 2021

In the theory of orthogonal polynomials, as well as in its intersection with harmonic analysis, it is an important problem to decide whether a given orthogonal polynomial sequence $$(P_n(x))_{n\in \mathbb {N}_0}$$

(

P
n

(
x
)

)

n
∈

N
0

satisfies nonnegative linearization of products, i.e., the product of any two $$P_m(x),P_n(x)$$

P
m

(
x
)

,

P
n

(
x
)

is a conical combination of the polynomials $$P_{|m-n|}(x),\ldots ,P_{m+n}(x)$$

P

|
m
-
n
|

(
x
)

,
…
,

P

m
+
n

(
x
)

. Since the coefficients in the arising expansions are often of cumbersome structure or not explicitly available, such considerations are generally very nontrivial. Gasper (Can J Math 22:582–593, 1970) was able to determine the set V of all pairs $$(\alpha ,\beta )\in (-1,\infty )^2$$

(
α
,
β
)

∈

(
-
1
,
∞
)

2

for which the corresponding Jacobi polynomials $$(R_n^{(\alpha ,\beta )}(x))_{n\in \mathbb {N}_0}$$

(

R
n

(
α
,
β
)

(
x
)

)

n
∈

N
0

, normalized by $$R_n^{(\alpha ,\beta )}(1)\equiv 1$$

R
n

(
α
,
β
)

(
1
)

≡
1

, satisfy nonnegative linearization of products. Szwarc (Inzell Lectures on Orthogonal Polynomials, Adv. Theory Spec. Funct. Orthogonal Polynomials, vol 2, Nova Sci. Publ., Hauppauge, NY pp 103–139, 2005) asked to solve the analogous problem for the generalized Chebyshev polynomials $$(T_n^{(\alpha ,\beta )}(x))_{n\in \mathbb {N}_0}$$

(

T
n

(
α
,
β
)

(
x
)

)

n
∈

N
0

, which are the quadratic transformations of the Jacobi polynomials and orthogonal w.r.t. the measure $$(1-x^2)^{\alpha }|x|^{2\beta +1}\chi _{(-1,1)}(x)\,\mathrm {d}x$$

(
1
-

x
2

)

α

|
x
|

2
β
+
1

χ

(
-
1
,
1
)

(
x
)

d
x

. In this paper, we give the solution and show that $$(T_n^{(\alpha ,\beta )}(x))_{n\in \mathbb {N}_0}$$

(

T
n

(
α
,
β
)

(
x
)

)

n
∈

N
0

satisfies nonnegative linearization of products if and only if $$(\alpha ,\beta )\in V$$

(
α
,
β
)
∈
V

, so the generalized Chebyshev polynomials share this property with the Jacobi polynomials. Moreover, we reconsider the Jacobi polynomials themselves, simplify Gasper’s original proof and characterize strict positivity of the linearization coefficients. Our results can also be regarded as sharpenings of Gasper’s one.
Current practice of concomitant surgeries in cartilage repair of the femorotibial compartment of the knee: baseline data of 4968 consecutive patients from the German cartilage registry (KnorpelRegister DGOU)
Authors: Zellner Johannes , Faber Svea , Spahn Gunter , Zinser Wolfgang , Niemeyer Philipp , Angele Peter
Published: July 2021

Introduction

The treatment of underlying comorbidities is a field of rising interest in cartilage repair surgery. The aim of this study was to analyze the current practice of concomitant surgeries in cartilage repair of the knee especially in the medial or lateral femorotibial compartment. Type, frequency and distribution of additional surgeries for correction of malalignment, knee instability and meniscus deficiency should be evaluated.

Methods

Baseline data of 4968 patients of the German Cartilage Registry (KnorpelRegister DGOU) were analyzed regarding the distribution of concomitant surgeries in addition to regenerative cartilage treatment.

Results

Beyond 4968 patients 2445 patients with cartilage defects in the femorotibial compartment of the knee could be identified. Of these patients 1230 (50.3%) received additional surgeries for correction of malalignment, instability and meniscus deficiency. Predominant procedures were leg axis corrections (31.3%), partial meniscectomy (20.9%) and ACL reconstruction (13.4%). The distribution of the concomitant surgeries varied between cartilage defects according to the different defect genesis. Patients with traumatic defects were younger (36y) and received predominantly ACL reconstructions (29.2%) (degenerative: 6.7%), whereas patients with degenerative defects were older (43y) and underwent predominantly leg axis corrections (38.0%; traumatic: 11.0%).

Conclusions

This study shows the high frequency and distinct distribution of the concomitant surgeries in addition to regenerative cartilage treatment procedures. Understanding of the underlying cause of the cartilage defect and addressing the comorbidities as a whole joint therapy are of utmost importance for a successful regenerative cartilage treatment. These data provide a baseline for further follow up evaluations and long-term outcome analysis.

Level of evidence

II.
Acute ischemic stroke in childhood: a comprehensive review
Authors: Mastrangelo Mario , Giordo Laura , Ricciardi Giacomina , De Michele Manuela , Toni Danilo , Leuzzi Vincenzo
Published: July 2021

This review provides an updated analysis of the main aspects involving the diagnosis and the management of children with acute ischemic stroke. Acute ischemic stroke is an emergency of rare occurrence in children (rate of incidence of 1/3500 live birth in newborns and 1–2/100,000 per year during childhood with peaks of incidence during the perinatal period, under the age of 5 and in adolescence). The management of ischemic stroke in the paediatric age is often challenging because of pleomorphic age-dependent risk factors and aetiologies, high frequency of subtle or atypical clinical presentation, and lacking evidence-based data about acute recanalization therapies. Each pediatric tertiary centre should activate adequate institutional protocols for the optimization of diagnostic work-up and treatments.

Conclusion: The implementation of institutional standard operating procedures, summarizing the steps for the selection of candidate for neuroimaging among the ones presenting with acute neurological symptoms, may contribute to shorten the times for thrombolysis and/or endovascular treatments and to improve the long-term outcome.

What is Known:•Acute ischemic stroke has a higher incidence in newborns than in older children (1/3500 live birth versus 1–2/100,000 per year).•Randomized clinical trial assessing safety and efficacy of thrombolysis and/or endovascular treatment were never performed in children

What is New:•Recent studies evidenced a low risk (2.1% of the cases) of intracranial haemorrhages in children treated with thrombolysis.•A faster access to neuroimaging and hyper-acute therapies was associated with the implementation of institutional protocols for the emergency management of pediatric stroke.
Evaluation and loss estimation of a high-speed permanent magnet synchronous machine with hairpin windings for high-volume fuel cell applications
Authors: Balasubramanian Sridhar , Langmaack Niklas , Henke Markus
Published: July 2021

High-speed machines offer several advantages, such as small sizes, avoidance of mechanical gears, and low maintenance, which has led to considerable research dedicated to them in the past decade. In recent times, rectangular wire windings with a hairpin structure have gained prominence in traction motors in the electromobility sector due to their high slot fill factor, simple production, and good thermal properties. Taking these advantages into consideration, this paper analyzes the possibility of using a high-speed permanent magnet synchronous machine (PMSM) with hairpin windings as an electric turbo compressor in fuel cell applications and outlines the critical design aspects.
Simultaneous septic arthrodesis of the tibiotalar and subtalar joints with the Ilizarov external fixator—an analysis of 13 patients
Authors: Cibura Charlotte , Lotzien Sebastian , Yilmaz Emre , Baecker Hinnerk , Schildhauer Thomas Armin , Gessmann Jan
Published: July 2021

Purpose

Treatment of joint destruction of the tibiotalar and subtalar joints caused by acute or chronic infections in compromised hosts is a challenging problem. In these cases, simultaneous septic arthrodesis with the use of the Ilizarov external fixator represents a possible alternative to amputation. This case series presents the results and complications of patients with acute or chronic infection of the tibiotalar and subtalar joints.

Methods

Between 2005 and 2015, 13 patients with acute or chronic infections were treated by simultaneous single-stage debridement/arthrodesis of the tibiotalar and subtalar joints. In seven patients, there was a florid infection with fistula formation and soft tissue defects, and in six patients, there was chronic osteomyelitis with closed soft tissue. In addition to the demographic data, the time spent in the fixator, the major and minor complications and the endpoint of consolidation were reviewed.

Results

The mean time spent in the fixator was 18 (min 15, max 26) weeks. The mean follow-up time for nine patients was 100 (min 3, max 341) weeks. Complete osseous consolidation of both the tibiotalar and subtalar joints was achieved in 10 patients (77%). In three (23%) patients, there was complete consolidation of one of the joints and partial consolidation of the other joint.

Conclusion

The Ilizarov external fixator allows for simultaneous arthrodesis of the tibiotalar and subtalar joints in septic joint destruction. However, the healing rates are below the rates reported in the literature for isolated tibiotalar or tibiocalcaneal arthrodesis in comparable clinical situations.
Dual task gait deteriorates gait performance in cervical dystonia patients: a pilot study
Authors: Crisafulli Oscar , Trompetto Carlo , Puce Luca , Marinelli Lucio , Costi Stefania , Abbruzzese Giovanni , Avanzino Laura , Pelosin Elisa
Published: July 2021

Day-to-day walking-related activities frequently involve the simultaneous performance of two or more tasks (i.e., dual task). Dual task ability is influenced by higher order cognitive and cortical control mechanisms. Recently, it has been shown that the concomitant execution of an attention-demanding task affected postural control in subject with cervical dystonia (CD). However, no study has investigated whether dual tasking might deteriorate gait performance in CD patients. To investigate whether adding a concomitant motor and cognitive tasks could affect walking performance in CD subjects.17 CD patients and 19 healthy subjects (HS) participated in this pilot case–control study. Gait performance was evaluated during four walking tasks: usual, fast, cognitive dual task and obstacle negotiation. Spatiotemporal parameters, dual-task cost and coefficients of variability (CV%) were measured by GaitRite® and were used to detect differences between groups. Balance performance was also assessed with Mini-BEST and Four Step Square tests. In CD participants, correlation analysis was computed between gait parameters and clinical data. Significant differences in complex gait and balance performance were found between groups. CD patients showed lower speed, longer stance time and higher CV% and dual-task cost compared to HS. In CD, altered gait parameters correlated with balance performance and were not associated with clinical features of CD. Our findings suggest that complex walking performance is impaired in patients with CD and that balance and gait deficits might be related
Fulminant Guillain–Barré syndrome developed after surgical treatment of intracranial hemorrhage due to arteriovenous malformation: a case report
Authors: Liu Hongyuan , Yang Liling , Li Zongping , Cheng Gang
Published: July 2021

Guillain–Barré syndrome (GBS) is a rare autoimmune disorder. GBS after surgical treatment of intracranial hemorrhage due to arteriovenous malformation (AVM) is even rarer. We present a 62-year-old man diagnosed with intracranial AVM and cerebral hemorrhage. He developed GBS after the operation for AVM and cerebral hemorrhage. Following surgical excision of AVM and cerebral hematoma, the patient developed generalized weakness, with subsequent quadriplegia and life-threatening dyspnea. The diagnosis was confirmed to be the acute motor–sensory axonal neuropathy subtype of GBS after cerebrospinal fluid analysis and antibody tests. The patient responded poorly to immunoglobulin and steroid therapy. His family abandoned further management and signed out of the hospital against medical advice. Despite being rare, GBS can occur after intracranial hemorrhage and surgery. Clinicians should rule out GBS when patients show no improvement or develop new neurologic
Comparing the first and the second waves of COVID-19 in Italy: differences in epidemiological features and CT findings using a semi-quantitative score
Authors: Balacchi Caterina , Brandi Nicolò , Ciccarese Federica , Coppola Francesca , Lucidi Vincenzo , Bartalena Laura , Parmeggiani Anna , Paccapelo Alexandro , Golfieri Rita
Published: July 2021

Purpose

CT findings of hospitalized COVID-19 patients were analyzed during both the first and the second waves of the pandemic, in order to detect any significant differences between the two groups.

Methods

In this observational, retrospective, monocentric study, all hospitalized patients who underwent CT for suspected COVID-19 pneumonia from February 27 to March 27, 2020 (first wave) and from October 26 to November 24, 2020 (second wave) were enrolled. Epidemiological data, radiological pattern according to the RSNA consensus statement and visual score extension using a semi-quantitative score were compared.

Results

Two hundred and eleven patients (mean age, 64.52 years ± 15.14, 144 males) were evaluated during the first wave while 455 patients (mean age, 68.26 years ± 16.34, 283 males) were studied during the second wave. The same prevalence of patterns was documented in both the first and the second waves (p = 0.916), with non-typical patterns always more frequently observed in elderly patients, especially the “indeterminate” pattern. Compared to those infected during the first wave, the patients of the second wave were older (64.52 vs.68.26, p = 0.005) and presented a slightly higher mean semi-quantitative score (9.0 ± 2.88 vs. 8.4 ± 3.06, p = 0.042). Age and semi-quantitative score showed a positive correlation (r = 0.15, p = 0.001).

Conclusions

There was no difference regarding CT pattern prevalence between the first and the second waves, confirming both the validity of the RSNA consensus and the most frequent radiological COVID-19 features. Non-typical COVID-19 features were more frequently observed in older patients, thus should not be underestimated in the elderly population.
Three-dimensional and real-scale modeling of flow regimes in dense snow avalanches
Authors: Li Xingyue , Sovilla Betty , Jiang Chenfanfu , Gaume Johan
Published: July 2021

Snow avalanches cause fatalities and economic loss worldwide and are one of the most dangerous gravitational hazards in mountainous regions. Various flow behaviors have been reported in snow avalanches, making them challenging to be thoroughly understood and mitigated. Existing popular numerical approaches for modeling snow avalanches predominantly adopt depth-averaged models, which are computationally efficient but fail to capture important features along the flow depth direction such as densification and granulation. This study applies a three-dimensional (3D) material point method (MPM) to explore snow avalanches in different regimes on a complex real terrain. Flow features of the snow avalanches from release to deposition are comprehensively characterized for identification of the different regimes. In particular, brittle and ductile fractures are identified in the different modeled avalanches shortly after their release. During the flow, the analysis of local snow density variation reveals that snow granulation requires an appropriate combination of snow fracture and compaction. In contrast, cohesionless granular flows and plug flows are mainly governed by expansion and compaction hardening, respectively. Distinct textures of avalanche deposits are characterized, including a smooth surface, rough surfaces with snow granules, as well as a surface showing compacting shear planes often reported in wet snow avalanche deposits. Finally, the MPM modeling is verified with a real snow avalanche that occurred at Vallée de la Sionne, Switzerland. The MPM framework has been proven as a promising numerical tool for exploring complex behavior of a wide range of snow avalanches in different regimes to better understand avalanche dynamics. In the future, this framework can be extended to study other types of gravitational mass movements such as rock/glacier avalanches and debris flows with implementation of modified constitutive laws.
Exploration of the high-redshift universe enabled by THESEUS
Authors: Tanvir N. R. , Le Floc’h E. , Christensen L. , Caruana J. , Salvaterra R. , Ghirlanda G. , Ciardi B. , Maio U. , D’Odorico V. , Piedipalumbo E. , Campana S. , Noterdaeme P. , Graziani L. , Amati L. , Bagoly Z. , Balázs L. G. , Basa S. , Behar E. , De Cia A. , Valle M. Della , De Pasquale M. , Frontera F. , Gomboc A. , Götz D. , Horvath I. , Hudec R. , Mereghetti S. , O’Brien P. T. , Osborne J. P. , Paltani S. , Rosati P. , Sergijenko O. , Stanway E. R. , Szécsi D. , Tot́h L. V. , Urata Y. , Vergani S. , Zane S.
Published: July 2021

At peak, long-duration gamma-ray bursts are the most luminous sources of electromagnetic radiation known. Since their progenitors are massive stars, they provide a tracer of star formation and star-forming galaxies over the whole of cosmic history. Their bright power-law afterglows provide ideal backlights for absorption studies of the interstellar and intergalactic medium back to the reionization era. The proposed THESEUS mission is designed to detect large samples of GRBs at z > 6 in the 2030s, at a time when supporting observations with major next generation facilities will be possible, thus enabling a range of transformative science. THESEUS will allow us to explore the faint end of the luminosity function of galaxies and the star formation rate density to high redshifts; constrain the progress of re-ionisation beyond $z\gtrsim 6$
z
≳
6
; study in detail early chemical enrichment from stellar explosions, including signatures of Population III stars; and potentially characterize the dark energy equation of state at the highest redshifts.
Bernhard Riemann, the Ear, and an Atom of Consciousness
Authors: Bell Andrew , Davies Bryn , Ammari Habib
Published: July 2021

Why did Bernhard Riemann (1826–1866), arguably the most original mathematician of his generation, spend the last year of life investigating the mechanism of hearing? Fighting tuberculosis and the hostility of eminent scientists such as Hermann Helmholtz, he appeared to forsake mathematics to prosecute a case close to his heart. Only sketchy pages from his last paper remain, but here we assemble some significant clues and triangulate from them to build a broad picture of what he might have been driving at. Our interpretation is that Riemann was a committed idealist and from this philosophical standpoint saw that the scientific enterprise was lame without the “poetry of hypothesis”. He believed that human thought was fundamentally the dynamics of “mind-masses” and that the human mind interpenetrated, and became part of, the microscopic physical domain of the cochlea. Therefore, a full description of hearing must necessarily include the perceptual dimensions of what he saw as a single manifold. The manifold contains all the psychophysical aspects of hearing, including the logarithmic transformations that arise from Fechner’s law, faithfully preserving all the subtle perceptual qualities of sound. For Riemann, hearing was a unitary physical and mental event, and parallels with modern ideas about consciousness and quantum biology are made. A unifying quantum mechanical model for an atom of consciousness—drawing on Riemann’s mind-masses and the similar “psychons” proposed by Eccles—is put forward.
Error Estimates of a Continuous Galerkin Time Stepping Method for Subdiffusion Problem
Authors: Yan Yuyuan , Egwu Bernard A. , Liang Zongqi , Yan Yubin
Published: July 2021

A continuous Galerkin time stepping method is introduced and analyzed for subdiffusion problem in an abstract setting. The approximate solution will be sought as a continuous piecewise linear function in time t and the test space is based on the discontinuous piecewise constant functions. We prove that the proposed time stepping method has the convergence order $$O(\tau ^{1+ \alpha }), \, \alpha \in (0, 1)$$

O

(

τ

1
+
α

)

,

α
∈

(
0
,
1
)

for general sectorial elliptic operators for nonsmooth data by using the Laplace transform method, where $$\tau $$
τ
is the time step size. This convergence order is higher than the convergence orders of the popular convolution quadrature methods (e.g., Lubich’s convolution methods) and L-type methods (e.g., L1 method), which have only $$O(\tau )$$

O
(
τ
)

convergence for the nonsmooth data. Numerical examples are given to verify the robustness of the time discretization schemes with respect to data regularity.
Perceptions of Spiritual Dryness in Iran During the COVID-19 Pandemic
Authors: Büssing Arndt , Kerdar Sara Hamideh , Akbari Mohammad Esmaeil , Rassouli Maryam
Published: July 2021

This study addresses perceptions of spiritual dryness (a specific form of spiritual struggle) during the COVID-19 pandemic among Iranian Muslims (n = 362), and how these perceptions can be predicted. Spiritual dryness was perceived often to regularly by 27% and occasionally by 35%. Regression models revealed that the best predictors of spiritual dryness (SDS-7) were usage of mood-enhancing medications, loneliness/social isolation and praying as positive predictors, and being restricted in daily life concerns as negative predictor. The pandemic challenges mental stability of people worldwide and may also challenge trust in God. Reliable and humble support of people experiencing these phases is required.
Architecture students and research courses: are they aligned? Students’ attitude towards research courses
Authors: Jansen S. J. T. , Boumeester H. J. F. M. , Rooij R. M.
Published: July 2021

Research courses are part of many higher education curricula. However, students’ attitudes towards statistics and research courses tend to be negative. One way to measure students’ attitude is with the Revised-Attitudes Towards Research scale (R-ATR). The current study examined: (1) the internal reliability of the R-ATR, (2) the attitude of Dutch second-year architecture students towards research courses, and (3) whether attitude is related to age and gender. It was found that the R-ATR has good internal reliability and that Dutch second-year architecture students’ attitude towards research courses is reasonably favorable. Students generally acknowledge the usefulness of research courses and do not feel anxious, but find them stressful and difficult to some extent and do not enjoy them. Further analyses showed three types of students: relaxed students, virtuous students and worried students, who each require a different approach to improving their attitude towards research courses. No relationship emerged between attitude and age or gender, but female students considered research courses somewhat more useful. Providing a research-friendly, enjoyable, and supportive environment might improve students’ attitude towards research courses.
Does the lack of root hairs alter root system architecture of Zea mays?
Authors: Lippold Eva , Phalempin Maxime , Schlüter Steffen , Vetterlein Doris
Published: July 2021

Aims

Root hairs are one root trait among many which enables plants to adapt to environmental conditions. How different traits are coordinated and whether some are mutually exclusive is currently poorly understood. Comparing a root hair defective mutant with its corresponding wild-type, we explored if and how the mutant exhibited root growth adaptation strategies and how dependent this was on substrate.

Methods

Zea maysroot hair defective mutant (rth3) and the corresponding wild-type siblings were grown under well-watered conditions on two substrates with contrasting texture and hence nutrient mobility. Root system architecture was investigated over time using repeated X-ray computed tomography.

Results

There was no plastic adaptation of root system architecture to the lack of root hairs, which resulted in lower uptake of nutrients especially in the substrate with high sorption capacity. The function of the root hairs for anchoring did not result in different root length density profiles between genotypes. Both maize genotypes showed a marked response to substrate. This was well reflected in the spatiotemporal development of rhizosphere volume fraction but especially in the highly significant response of root diameter to substrate, irrespective of genotype.

Conclusions

The most salient root plasticity trait was root diameter in response to substrate. Coping mechanisms for missing root hairs were limited to a shift in root-shoot ratio in loam. Further experiments are required, to elucidate whether observed differences can be explained by mechanical properties beyond mechanical impedance, root or microbiome ethylene production or differences in diffusion processes within the root or the rhizosphere.
Vitamin D, infections and immunity
Authors: Ismailova Aiten , White John H.
Published: July 2021

Vitamin D, best known for its role in skeletal health, has emerged as a key regulator of innate immune responses to microbial threat. In immune cells such as macrophages, expression of CYP27B1, the 25-hydroxyvitamin D 1α-hydroxylase, is induced by immune-specific inputs, leading to local production of hormonal 1,25-dihydroxyvitamin D (1,25D) at sites of infection, which in turn directly induces the expression of genes encoding antimicrobial peptides. Vitamin D signaling is active upstream and downstream of pattern recognition receptors, which promote front-line innate immune responses. Moreover, 1,25D stimulates autophagy, which has emerged as a mechanism critical for control of intracellular pathogens such asM. tuberculosis. Strong laboratory and epidemiological evidence links vitamin D deficiency to increased rates of conditions such as dental caries, as well as inflammatory bowel diseases arising from dysregulation of innate immune handling intestinal flora. 1,25D is also active in signaling cascades that promote antiviral innate immunity; 1,25D-induced expression of the antimicrobial peptide CAMP/LL37, originally characterized for its antibacterial properties, is a key component of antiviral responses. Poor vitamin D status is associated with greater susceptibility to viral infections, including those of the respiratory tract. Although the severity of the COVID-19 pandemic has been alleviated in some areas by the arrival of vaccines, it remains important to identify therapeutic interventions that reduce disease severity and mortality, and accelerate recovery. This review outlines of our current knowledge of the mechanisms of action of vitamin D signaling in the innate immune system. It also provides an assessment of the therapeutic potential of vitamin D supplementation in infectious diseases, including an up-to-date analysis of the putative benefits of vitamin D supplementation in the ongoing COVID-19 crisis.
Obstructive sleep apnea syndrome in non-obese patients
Authors: Antonaglia Caterina , Passuti Giovanna
Published: July 2021

Obstructive sleep apnea syndrome (OSAS) is characterized by symptoms and signs of more than 5 apneas per hour (AHI) at polysomnography or 15 or more apneas per hour without symptoms. In this review, the focus will be a subgroup of patients: adult non-obese subjects with OSA and their specific features. In non-obese OSA patients (patients with BMI < 30 kg/m2), there are specific polysomnographic features which reflect specific pathophysiological traits. Previous authors identified an anatomical factor (cranial anatomical factors, retrognatia, etc.) in OSA non-obese. We have hypothesized that in this subgroup of patients, there could be a non-anatomical pathological prevalent trait. Little evidence exists regarding the role of low arousal threshold. This factor could explain the difficulty in treating OSA in non-obese patients and emphasizes the importance of a specific therapeutic approach for each patient.