bluuebunny/crossref_metadata_2025 huggingface dataset:
Canada
Authors: Tremblay Jean-François
Published: July 2023

Canada has evolved into one of the most fiscally decentralized federations in the world. Provinces enjoy considerable autonomy and play a central role in designing and implementing economic and social policies. This chapter outlines key features of Canadian fiscal federalism, especially the extensive decentralization of legislative responsibilities and taxation powers to provincial governments, the wide-ranging intergovernmental transfer system designed to maintain fiscal balance between orders of governments and among provinces, as well as the mechanisms in place to promote some harmonization of policies and cooperation among provinces. Current challenges to Canadian fiscal federalism are outlined including pressures on horizontal and vertical fiscal balance associated with demographic changes, rapidly increasing costs in the public health care system which have been intensified by the Covid-19 pandemic, persistent tensions associated with the geographic concentration of natural resources, as well as pressures on municipal finance resulting from ongoing urbanization and growing infrastructure needs, among others.
Ethiopia
Authors: Senbeta Sisay Regassa , Hundie Yakob Bekele
Published: July 2023

Fiscal federalism in Ethiopia has been implemented within a unique political context. The adoption of a multiethnic federal system has reshaped the fiscal and economic landscape of the country since 1991. Following the political restructuring towards federalization, the culture of centralization of fiscal powers and responsibilities, which had been witnessed for more than half a century, has significantly been altered. Yet, Ethiopia is a highly centralized federation, both in design and practice. The division of powers favors the Federal government in legislation and policymaking. The provision of most public services is, however, significantly decentralized. The lucrative sources of revenue are assigned to be either exclusive federal powers or concurrent. As a result, Ethiopia’s fiscal federalism has been characterized by a high degree of fiscal imbalances, the Federal General-Purpose Grant (FGPG), an equalization transfer, being the dominant mechanism to bridge the imbalances. Revenue sharing and specific purpose transfers constitute only a very small proportion of Subnational finance. States’ borrowing rights are limited to internal sources and are subject to stringent preconditions set by the federal government.
Fiscal Federalism in Germany
Authors: Bury Yannick , Feld Lars P.
Published: July 2023

From the year 2020 onwards, major constitutional changes have inverted former principles of German fiscal federalism and have led to further vertical fiscal imbalances. The latest reform of Germany’s fiscal federalism strengthens the federal level in general and the executive branches at the federal and state (Laender) tiers of government in particular at the expense of the Laender and their parliaments, respectively. In view of this development, this chapter provides an overview of the components of fiscal federalism in Germany. After providing a brief characterization of the country, we discuss the division of fiscal powers, the possibilities for the different levels of government to generate revenues, and the system of intergovernmental transfers. Besides describing the current situation, we discuss how the latest reform act has changed these dimensions of fiscal federalism since 2020.
South Africa
Authors: Mabugu Ramos Emmanuel , Rakabe Eddie M.
Published: July 2023

This chapter focuses on contemporary issues in South Africa’s evolving and unique system of quasi-federal governance. In what appears to be an unending and polymorphous federal reforms further complicated by the ongoing COVID-19 imposed fiscal pressures, the chapter explores the rationale and effectiveness of constitutional and fiscal institutions underpinning South Africa’s multi-level governance. Coming from a difficult apartheid past, the country was able to install a “compromised” intergovernmental relations system, constituted by the Constitution as three spheres of government that are distinctive, interrelated and interdependent. The system is supported by a myriad of enabling legislations and institutions to harness accountability and fiscal management as well as the intergovernmental transfers to facilitate delivery of basic services. Notwithstanding the legislative and institutional framework, the system is beset by a gamut of challenges as it evolves in search of an identity. Foremost among these challenges is the absence of political commitment and clear vision for decentralisation, which manifest (and often impinge) in the execution of concurrent, own and delegated expenditure responsibilities and more importantly the assignment of taxing powers across the three spheres of government. As the system continues to mature in search of optimal decentralisation, this chapter argues for a “clearer federalism vision” around which intergovernmental fiscal relations reforms could be anchored.
Constructing the Self Between Worlds
Authors: Kullberg Christina
Published: July 2023

This chapter shifts the attention toward another point of entanglement, namely the construction of the travelers’ self as a changing narrative category within the travel narratives. Drawing on recent research around the complex development of the notion of the self in the seventeenth century, the argument is that the self is unstable and multiple; it mediates between the space of reception (France) and the space described (the Islands). The self thus becomes a site where the effect of otherness can be traced: it becomes a narrative locus of unsettlement where the impact of early island society and its people is visible on several levels. The first section is devoted to the conditions governing travel writing in order to understand how the travelers used this strategically in their representations of the islands in terms of both distance and embodiment. The second section centers on Labat’s travelogue in order to analyze how that embodiment led to the construction of an experimental self influenced by the islands: the individual traveler’s experience becomes a way to think through the social body’s experience. The third section examines how the self negotiates encounters with others. By interrogating the figure of the commentary, it questions the construction of a discourse of ambivalence, bordering on sentimentality, with regard to enslaved peoples and enslavement as an institution. The last section looks closer at engagements with Indigenous peoples in terms of an anxiety of influence: the narratives configure that influence through style. The travelers, it claims, both underscore and distance themselves to uphold an intermediary position.
Review of Theories and a New Classification of Tortuosity Types
Authors: Holzer Lorenz , Marmet Philip , Fingerle Mathias , Wiegmann Andreas , Neumann Matthias , Schmidt Volker
Published: July 2023

Many different definitions of tortuosity can be found in literature. In addition, also many different methodologies are nowadays available to measure or to calculate tortuosity. This leads to confusion and misunderstanding in scientific discussions of the topic. In this chapter, a thorough review of all relevant tortuosity types is presented. Thereby, the underlying concepts, definitions and associated theories are discussed in detail and for each tortuosity type separately. In total, more than 20 different tortuosity types are distinguished in this chapter. In order to avoid misinterpretation of scientific data and misunderstandings in scientific discussions, we introduce a new classification scheme for tortuosity, as well as a systematic nomenclature, which helps to address the inherent differences in a clear and efficient way. Basically, all relevant tortuosity types can be grouped into three main categories, which are (a) the indirect physics-based tortuosities, (b) the direct geometric tortuosities and (c) the mixed tortuosities. Significant differences among these tortuosity types are detected, when applying the different methods and concepts to the same material or microstructure. The present review of the involved tortuosity concepts shall serve as a basis for a better understanding of the inherent differences. The proposed classification and nomenclature shall contribute to more precise and unequivocal descriptions of tortuosity.
Towards a Quantitative Understanding of Microstructure-Property Relationships
Authors: Holzer Lorenz , Marmet Philip , Fingerle Mathias , Wiegmann Andreas , Neumann Matthias , Schmidt Volker
Published: July 2023

100 years ago, the concept of tortuosity was introduced by Kozeny in order to express the limiting influence of the microstructure on porous media flow. It was also recognized that transport is hindered by other microstructure features such as pore volume fraction, narrow bottlenecks, and viscous drag at the pore surface. The ground-breaking work of Kozeny and Carman makes it possible to predict the macroscopic flow properties (i.e., permeability) based on the knowledge of the relevant microstructure characteristics. However, Kozeny and Carman did not have access to tomography and 3D image analysis techniques, as it is the case nowadays. So, their descriptions were developed by considering simplified models of porous media such as parallel tubes and sphere packings. This simplified setting clearly limits the prediction power of the Carman-Kozeny equations, especially for materials with complex microstructures. Since the ground-breaking work of Kozeny and Carman many attempts were undertaken to improve the prediction power of quantitative expressions that describe the relationship between microstructure characteristics (i.e., tortuosity τ, constrictivity β, porosity ε, hydraulic radius rh) and effective transport properties (i.e., conductivity σeff, diffusivity Deff, permeability к,). Due to the ongoing progress in tomography, 3D image-processing, stochastic geometry and numerical simulation, new possibilities arise for better descriptions of the relevant microstructure characteristics, which also leads to mathematical expressions with higher prediction power. In this chapter, the 100-years evolution of quantitative expressions describing the micro–macro relationships in porous media is carefully reviewed,—first, for the case of conduction and diffusion,—and second, for flow and permeability.

The following expressions are the once with the highest prediction power:$$\sigma_{eff} \left( {or D_{eff} } \right) = \varepsilon^{1.15} \beta^{0.37} /\tau_{{dir_{geodesic} }}^{4.39} ,$$

σ

eff

o
r

D

eff

=

ε

1.15

β

0.37

/

τ

d
i

r

geodesic

4.39

,

for conduction and diffusion, and$$\kappa_{I} = 0.54\left( {\frac{\varepsilon }{{S_{V} }}} \right)^{2} \frac{{\varepsilon^{3.56} \beta^{0.78} }}{{\tau_{dir\_geodesic}^{1.67} }},$$

κ
I

=
0.54

ε

S
V

2

ε

3.56

β

0.78

τ

d
i
r
_
g
e
o
d
e
s
i
c

1.67

,

$$\kappa_{II} = \frac{{\left( {0.94r_{min} + 0.06r_{max} } \right)^{2} }}{8} \frac{{\varepsilon^{2.14} }}{{\tau_{dir\_geodesic}^{2.44} }},$$

κ

II

=

0.94

r

min

+
0.06

r

max

2

8

ε

2.14

τ

d
i
r
_
g
e
o
d
e
s
i
c

2.44

,

both, for permeability in porous media.
Summary and Conclusions
Authors: Holzer Lorenz , Marmet Philip , Fingerle Mathias , Wiegmann Andreas , Neumann Matthias , Schmidt Volker
Published: July 2023

A short summary is provided for each chapter of the book, which includes a review of theories and a new classification of tortuosity types (chapter 2), a review of empirical data (tortuosity-porosity relationships) from literature (chapter 3), a review of image based methodologies, workflows, and calculation approaches for tortuosity (chapter 4), and a review of quantitative expressions for microstructure—property relationships considering transport in porous media (chapter 5). As a final conclusion, interpretations are given for the three main tortuosity categories: direct geometric, indirect physics-based and mixed tortuosities.
The Effect of Fishing Nets Aging on Metal Uptake
Authors: Lima Ana Teresa Macas , Bertelsen Ida Maria Gieysztor , Ottosen Lisbeth Mølgaard , James Neil A.
Published: July 2023

Fishing nets are mainly constituted of Polyethylene (PE), Polyamide, Polyethylene terephthalate (PET), Polypropylene (PP), and Nylon. While new, these plastics exhibit pristine mechanical performance but lose it as they age. But what about their metal adsorptive performance? Literature finds that plastics like PET and PVC accumulate Al, Cr, Mg, Fe, Co, Ni, Zn, Cd, and Pb, even when exposed to very low concentrations. This is mainly true for aged PVC (Kedzierski et al. Adsorption/desorption of Micropollutants. Mar Pollut Bull. 127:684–694, 2018). In this study, we look at the effect of age on the properties of fishing nets, including their capacity to adsorb metals. Because fishnets are in great part constituted by PE, we used standardized PE pellets as our reference. In calorimeter signaling, we observed that end-of-life fishing nets display a very different differential scanning calorimetry (DSC) pattern; both new and old fishing nets are very different from standardized PE polymer. Preliminary results show that Cr, Cu, Pb, and Se adsorption onto fishing nets occurs in the first 10 min to 6 h of exposure (24 h for Se). The maximum uptake was registered at 11 mg Cr kg‒1, 38 mg Cu kg‒1, 27 mg Pb kg‒1, and 15 mg Se kg‒1. All these concentrations refer to old end-of-life PE fishing nets, where new, unused PE fishing nets adsorb 2–20 times less (Old in this chapter refers to used fishing nets. The term is not attempting to attribute a particular life span/age to the nets). A comparison to different EU directives that regulate metal content in plastics for different end-uses shows that the old end-of-life PE fishing nets, after exposure to heavy metals, do not meet the regulations for hazardous waste. We believe that Greenlandic old waste fishing nets can be used to clean the wastewater, or metal-contaminated water, in Greenland and eventually, the rest of the world.
Quadruple Helix Relational Approach to Recycling Fishing Nets: Cluster Development in the Norwegian West Coast Region
Authors: Vaagen Hajnalka , Tippett Arron Wilde
Published: July 2023

The study presented in this chapter takes the quadruple helix relational perspective to develop a regional innovation cluster for fishing nets recycling and upcycling. A multi-method approach is proposed—triangulating cluster development approaches with the quadruple helix model of innovation and organisational network analysis—to explore clustering abilities by network structures that promote linkages for well-organised circular value chains, regional innovation processes, brokerage of innovative ideas and other cluster-related structures, and relational patterns.
The Role of Non-profit Organisations (NGOs) in Value Creation: Lessons from the Recycling of Fishing Gear in Norway
Authors: Glavee-Geo Richard , AI Ahmed Sardar Wasi Uddin , Tippett Arron Wilde , Grimstad Siv Marina Flø , Pasquine Mark
Published: July 2023

Value chain collaboration and volunteering by non-governmental organisations (NGOs) are success factors that enhance fishing gear recycling. Using multiple cases of NGOs from the Norwegian value chain of recycled plastic fishing gear, we highlight the role of NGOs in fishing gear recycling through collaborative partnerships with small- and medium-sized enterprises (SMEs). The Blue Circular Economy (BCE) project provided us with the opportunity to understudy and highlight this contextually rich phenomenon. Our study shows that sustainable value creation can be achieved through marine plastics recycling, value chain collaboration, volunteering initiatives/operations, and local innovation system (LIS) leading to new process, service, and product development. The chapter provides increased understanding of the role of NGOs within the value chain. Value chain collaboration between SMEs and NGOs stimulates innovation in the local environment (LIS) and within the industry. Collaboration drives the innovation process and enhances recycling of marine plastics. Marine plastics with a focus on waste fishing gear recycling can lead to sustainable value creation. NGOs therefore occupy a key position in the value chain not only for advocacy, but also for value creation.
Symmetric Cryptography
Authors: Weissbaum François , Lugrin Thomas
Published: July 2023

Symmetric encryption is the most common method to guarantee the confidentiality of a message or information. Encryption is a cryptographic process that makes it impossible for anyone who needs the decryption key to gain knowledge of plaintext. It is called symmetric when it uses the same key for encryption and decryption. The required key length for symmetric encryption must be at least 256 bits to guarantee sufficient protection against brute force attacks and the possible arrival of quantum computers. To conclude, well-established cryptographic libraries implementing standard algorithms should be preferred over homemade implementation.
Biometrics
Authors: Ding Sophia , Nunes Emilia , Bettendorff Pascal , Lin Weyde
Published: July 2023

In biometrics, physiological characteristics (e.g., fingerprints, facial features, voices) are measured to identify individuals. Since biometry does not share the same characteristics as other authentication techniques, such as passwords or PIN codes, it is widely used as a second-factor authentication. A fully integrated solution offers significant advantages as it aligns biometric hardware, key generation, validation, and storage with the cryptographic provider, providing a coherent control environment. As a result, designing and implementing secure biometric authentication methods requires highly specialized technical expertise and experience. In addition, as biometrics become prevalent and their integration with artificial intelligence systems increases, ethical and regulatory questions become more pressing.
Secure Positioning and Localization
Authors: Strohmeier Martin
Published: July 2023

Secure positioning and localization refer to the use of technology to accurately determine the location of an object or person in a secure and trustworthy manner. It involves GPS, Bluetooth, Wi-Fi, and other wireless technologies to determine location. Several methods have been proposed to address this problem by securing the content of the signals cryptographically. Distance bounding and timed efficient stream loss-tolerant authentication are two leading examples. Furthermore, with autonomous vehicles becoming increasingly essential and utilized in all domains (land, water, air), secure and robust positioning and navigation capabilities will be crucial.
Email Security
Authors: Nunes Emilia
Published: July 2023

Emails were not designed with cyber-attack protection in mind, making them an attractive target for cybercriminals. A primary attack vector is phishing, a type of social engineering in which a fraudulent message is sent to trick a person. however, email messages can be secured using cryptography. For example, end-to-end encryption could protect them in transit and at rest. In addition, transport Layer Security is used to protect emails in transit between email servers and clients. Nevertheless, emails may never be as secure as newly designed solutions with solid end-to-end encryption and robust architecture.
Secure Messaging
Authors: Nunes Emilia
Published: July 2023

A message is defined as any piece of information that a person communicates to another individual or group. On the other hand, a secure messaging system protects and secures individuals’ and organizations’ communication infrastructure. End-to-end encryption uses encryption and decryption keys to ensure the privacy of messages and the authenticity of the sender and recipient. Technological advancements, such as cloud-based and blockchain-based platforms, drive growth in the secure messaging market. However, risks like phishing and cyberattacks remain persistent and are projected to continue targeting messages in the future.
Trends in Open Source Software for Data Protection and Encryption Technologies
Authors: Teijeiro Lucía Gómez , Maillart Thomas
Published: July 2023

Software editors and practitioners have increasingly developed and used open-source software tools to implement their cybersecurity strategies. By its unique intellectual property regime, open-source software fosters transparency and sharing values, which have been recognized as important to finding and fixing vulnerabilities and quickly avoiding threats. By selecting 41 technologies related to the one presented in the book, we show that open-source software for cybersecurity is a rapidly growing complex ecosystem of 3456 GitHub repositories with 5000+ users. While some repositories are prominent, many have evolved under the radar, serving niche or emergent needs. Here, we provide the first account of trends in open-source software for cybersecurity and develop a non-parametric forecasting approach to provide an outlook of its development towards 2025.
Hash Functions
Authors: Wagner Urs , Lugrin Thomas
Published: July 2023

Hash functions are one-way functions that map arbitrary-length input to fixed-length output. Moreover, they have many cryptographic applications, such as integrity checks, password storage, and signatures. Cryptographic hash functions have some additional properties that can be formulated as hard problems: pre-image resistance, second pre-image resistance, and collision resistance. A significant technological development in this area is unlikely. Standardized hash functions are considered secure, and open-source implementations can be used at no cost. To conclude, the security properties required from hash functions depend on the intended purpose.
Zero-Knowledge Proof
Authors: Aad Imad
Published: July 2023

Zero-knowledge proofs are techniques to verify claims without revealing the information itself. In this process, a “prover” shares proof of their claim with a “verifier,” who then verifies the accuracy of the proof without learning any additional information. It does not prove things with certainty. Instead, the process is repeated as often as needed, eventually reaching near-certainty. Zero-knowledge proofs are still in their early days as open initiatives and standardization efforts involve industry, academia, and technical and non-technical specialist. There are different Zero-knowledge proof systems for different use cases, most of which are either being researched or open-source implementation.
Quantum Key Distribution
Authors: Rödiger Jasper
Published: July 2023

A new class of computers, so-called quantum computers, will soon be able to crack common encryption algorithms. Quantum key distribution is a promising solution to stay secure in the age of the quantum computer, which is progressively getting industrialized in recent years. Worldwide, point-to-point quantum key distribution links are combined into larger and larger testbed networks, which approach more and more commercially usable networks. Topics like certification and standardization have become increasingly important for quantum key distribution.
Bioinspired Soft Actuator Based on Photothermal Expansion of Biodegradable Polymers
Authors: Cecchini Luca , Mariani Stefano , Pugno Nicola M. , Mazzolai Barbara
Published: July 2023

The combined effects of thermo-sensitive and photothermal materials present novel actuation strategies for wireless application and the use of sustainable energy sources, such as the sunlight. To understand the operating features of multifunctional materials, bioinspired multi-layer actuators represent a simple solution as a testing platform. Here, we report the fabrication of a bilayer photothermal and biodegradable bending actuator, based on thermal expansion of polycaprolactone-lignin blend, 3D printed on cellulose acetate substrate. When the actuator is irradiated with 300 mW/cm2 of simulated solar irradiance, it shows a change in curvature of 25.34%, with a bending moment of ~80.2 µN · m and with a characteristic actuation time of 30 s. Moreover, the photothermal blend shows a conversion efficiency of 13.5%. Due to the photothermal and biodegradability properties, the actuator could be used as a battery-free tool for different tasks, in a scenario where no contamination of the environment is required.
Translation-Like Isoptic Surfaces and Angle Sums of Translation Triangles in $$\textbf{Nil}$$ Geometry
Authors: Csima Géza , Szirmai Jenő
Published: July 2023

After having investigated the geodesic and translation triangles and their angle sums in$$\textbf{Sol}$$Soland$$\widetilde{{\textbf{S}}{\textbf{L}}_2{\textbf{R}}}$$SL2R~geometries we consider the analogous problem in$$\textbf{Nil}$$Nilspace that is one of the eight 3-dimensional Thurston geometries. We analyze the interior angle sums of translation triangles in$$\textbf{Nil}$$Nilgeometry and we provide a new approach to prove that it can be larger than or equal to$$\pi $$π. Moreover, for the first time in non-constant curvature Thurston geometries we have developed a procedure for determining the equations of$$\textbf{Nil}$$Nilisoptic surfaces of translation-like segments and as a special case of this we examine the$$\textbf{Nil}$$Niltranslation-like Thales sphere, which we callThaloid. In our work we will use the projective model of$$\textbf{Nil}$$Nildescribed by Molnár (Beitr Algebra Geom 38(2):261–288, 1997).
Extremal Structure of Projective Tensor Products
Authors: García-Lirola Luis C. , Grelier Guillaume , Martínez-Cervantes Gonzalo , Rueda Zoca Abraham
Published: July 2023

We prove that, given two Banach spaces X and Y and bounded, closed convex sets $$C\subseteq X$$

C
⊆
X

and $$D\subseteq Y$$

D
⊆
Y

, if a nonzero element $$z\in {\overline{{{\,\textrm{co}\,}}}}(C\otimes D)\subseteq X\widehat{\otimes }_\pi Y$$

z
∈

co

¯

(
C
⊗
D
)

⊆
X

⊗
^

π

Y

is a preserved extreme point then $$z=x_0\otimes y_0$$

z
=

x
0

⊗

y
0

for some preserved extreme points $$x_0\in C$$

x
0

∈
C

and $$y_0\in D$$

y
0

∈
D

, whenever $$K(X,Y^*)$$

K
(
X
,

Y
∗

)

separates points of $$X \widehat{\otimes }_\pi Y$$

X

⊗
^

π

Y

(in particular, whenever X or Y has the compact approximation property). Moreover, we prove that if $$x_0\in C$$

x
0

∈
C

and $$y_0\in D$$

y
0

∈
D

are weak-strongly exposed points then $$x_0\otimes y_0$$

x
0

⊗

y
0

is weak-strongly exposed in $${\overline{{{\,\textrm{co}\,}}}}(C\otimes D)$$

co

¯

(
C
⊗
D
)

whenever $$x_0\otimes y_0$$

x
0

⊗

y
0

has a neighbourhood system for the weak topology defined by compact operators. Furthermore, we find a Banach space X isomorphic to $$\ell _2$$

ℓ
2

with a weak-strongly exposed point $$x_0\in B_X$$

x
0

∈

B
X

such that $$x_0\otimes x_0$$

x
0

⊗

x
0

is not a weak-strongly exposed point of the unit ball of $$X\widehat{\otimes }_\pi X$$

X

⊗
^

π

X

.
Dynamic Crack Growth in Viscoelastic Materials with Memory
Authors: Cianci Federico
Published: July 2023

In this paper we introduce a model of dynamic crack growth in viscoelastic materials, where the damping term depends on the history of the deformation. The model is based on a dynamic energy dissipation balance and on a maximal dissipation condition. Our main result is an existence theorem in dimension two under some a priori regularity constraints on the cracks.
High degree of consensus on diagnosis and management of rotator cuff tears: a Delphi approach
Authors: Saccomanno Maristella F. , Lisai Andrea , Romano Alfonso Maria , Vitullo Andrea , Pannone Antonello , Spoliti Marco , Di Giunta Angelo C. C. , Castricini Roberto , Giordano Matthew C.
Published: July 2023

Purpose

To develop a consensus on diagnosis and treatment of rotator cuff tears. The study focused on selected areas: imaging, prognostic factors, treatment options, surgical techniques.

Methods

Panel was composed of all members of the shoulder committee of the Italian Society of Arthroscopy, Knee, Upper arm, Sport, Cartilage and Orthopedic techniques (SIAGASCOT). Four rounds were performed. The first round consisted of gathering questions which were then divided into seven blocks referring to: imaging, patient‐related prognostic factors, treatment options, surgical steps, reparative techniques, surgical predictive factors, advanced techniques. Subsequent rounds consisted of condensation by means of online questionnaire and debates. Consensus was defined as two‐thirds agreement on one answer. Descriptive statistic was used to summarize the data.

Results

Forty‐one shoulder experts were involved. Fifty‐six statements were finally formulated. A consensus could be achieved on 51. Experts agreed that preoperative magnetic resonance imaging is strongly recommended because it allows a careful evaluation of tear characteristics, while the role of US remains debatable. Controversial patient‐related factors such as age, comorbidities, smoking and stiffness do not contraindicate the repair. From a surgical standpoint, the experts highlighted that pseudo‐paralysis is not a contraindication to rotator cuff repair. Consensus on specific surgical steps was also achieved: capsular release should be performed only in stiff shoulders; footprint preparation is mandatory, while debridement of tendon edges is not essential. If necessary, a rotator interval release could be performed without interrupting the continuity between subscapularis and supraspinatus tendon; posterior delamination should be always included in the repair. Advanced techniques such as tendon transfers should be selected based on the main clinical deficit, while the superior capsule reconstruction plays a role only in combination with a functional repair.

Conclusion

A consensus was achieved almost on every topic of controversy explored. Particularly, MRI was deemed necessary to determine tear characteristics, while radiographs remain important for differential diagnosis; age should not be considered a contraindication to surgery; pseudo‐paralysis does not represent a contraindication to arthroscopic rotator cuff repair, but superior capsule reconstruction plays a role only in combination with a functional repair. Latissimus dorsi transfer plays a role when the main functional deficit is in elevation, while the lower trapezius transfer plays a role when the main functional deficit is the external‐rotation.

Level of evidence

V.
Computational study of the adamantane cation: simulations of spectroscopy, fragmentation dynamics, and internal conversion
Authors: Roy Bonasree , Titov Evgenii , Saalfrank Peter
Published: July 2023

Diamondoids, of which adamantane (C$$_{10}$$

10

H$$_{16}$$

16

) is the simplest representative, constitute an intriguing class of carbon based nanomaterials with interesting chemical, mechanical and opto-electronic properties. While neutral diamondoids have been extensively studied for decades, their cationic counterparts were a subject of recent experimental investigations motivated by their potential role in astrochemistry. Here, we perform a computational study of the adamantane cation (C$$_{10}$$

10

H$$_{16}^+$$

16

+

) complementing the recent experimental findings. Specifically, we extend earlier theoretical work on vibrationally resolved electronic spectroscopy by accounting for the higher lying electronically excited states of the cation in the absorption and photoelectron spectra. We also perform adiabatic and nonadiabatic (surface hopping) molecular dynamics simulations to study (fast) fragmentation processes and electronic relaxation of C$$_{10}$$

10

H$$_{16}^+$$

16

+

. Our simulations reveal that after excitation with near-infrared–ultraviolet photons, the adamantane cation undergoes an ultrafast internal conversion to the ground (doublet) state (on a time scale of 10–100 fs depending on initial excitation energy) which can be followed by a fast fragmentation, predominantly H loss. The yield of the ultrafast hydrogen dissociation as a function of excitation energy is reported.
Clinical outcome following magnetic resonance imaging as first-line imaging in low-impact pediatric spine trauma: a single-center retrospective observational study
Authors: Sirén Aapo , Nyman Mikko , Syvänen Johanna , Mattila Kimmo , Hirvonen Jussi
Published: July 2023

Background

Pediatric spinal trauma is rare, but the consequences of a missed injury can be devastating. Medical imaging is often needed in addition to physical examination. Conventional radiographs are widely recommended, but their negative predictive value is limited. Computed tomography (CT) is more sensitive but has a higher radiation dose. Magnetic resonance imaging (MRI) has superior soft tissue contrast and lacks ionizing radiation, but it is more expensive and time-consuming. Thus, the debate regarding the most suitable imaging method is still ongoing.

Objective

This study examined the ability of MRI to exclude injuries requiring surgical treatment as a first-line imaging method in low-impact pediatric spine trauma.

Materials and methods

We retrospectively reviewed the medical records and imaging data of children (under 18 years old) who had suspected spinal trauma and were scanned using MRI in our emergency radiology department over a period of 8 years. We assessed the ability of MRI to detect unstable injuries by searching for later occurrences of primarily missed injuries requiring surgery.

Results

Of 396 patients (median age 12 years, range 0–17), 114 (29%) had MRI findings suggesting an acute injury. Bony injuries were detected in 78 patients (20%) and ligamentous or other soft tissue injuries in 82 patients (21%). In the subgroup of 376 patients (median age 12 years, range 0–17) with at least 6 months of clinical follow-up, no missed injuries demanding surgical intervention or immobilization occurred after spinal MRI as  first-line imaging. No adverse events related to MRI or anesthesia occurred.

Conclusion

MRI can detect injuries requiring surgical treatment as a first-line imaging method in suspected low-impact pediatric spinal trauma and is safe to use in this selected population.

Graphical abstract
Left fourth and sixth costovertebral dislocation abutting the aorta
Authors: Gorelik Natalia , Croteau Dany , Gorelik Valérie , Casullo Joseph
Published: July 2023

While rib fractures are common in blunt thoracic trauma, dislocations of the costovertebral joints (CVJs) are extremely rare and typically involve the first, eleventh, or twelfth rib. We report a rare case of dislocation of the left fourth and sixth CVJs in a 36-year-old man who was run over by a car. The rib heads were displaced anteriorly, abutting the aorta. Additional injuries included bilateral hemopneumothoraces, pneumomediastinum, pulmonary contusions, grade 3 splenic injury, left adrenal hematoma, retroperitoneal hematoma, Morel-Lavallée lesions at bilateral hips, and multiple fractures, including at the ribs and pelvis. There was also a fracture of the fourth thoracic vertebral body, which was occult on initial CT, but seen on subsequent CTs. The CVJ dislocations were managed conservatively, without short-term complications. Prompt surgical intervention has been recommended in cases where sharp rib fracture fragments are displaced close to the aorta to prevent fatal aortic injuries. However, there is a literature gap on the management of rib heads that are dislocated against the aorta. Our experience suggests that conservative management may be acceptable in some of these cases. This case report aims to increase radiologists’ awareness of CVJ injuries, which are important for thoracic spine stability, and highlights the association between CVJ dislocations and spinal injuries.
Melanoma-derived soluble mediators modulate neutrophil biological properties and the release of neutrophil extracellular traps
Authors: Modestino Luca , Cristinziano Leonardo , Trocchia Marialuisa , Ventrici Annagioia , Capone Mariaelena , Madonna Gabriele , Loffredo Stefania , Ferrara Anne Lise , Romanelli Marilena , Simeone Ester , Varricchi Gilda , Rossi Francesca Wanda , de Paulis Amato , Marone Gianni , Ascierto Paolo Antonio , Galdiero Maria Rosaria
Published: July 2023

Polymorphonuclear neutrophils (PMNs) are the main effector cells in the inflammatory response. The significance of PMN infiltration in the tumor microenvironment remains unclear. Metastatic melanoma is the most lethal skin cancer with an increasing incidence over the last few decades. This study aimed to investigate the role of PMNs and their related mediators in human melanoma. Highly purified human PMNs from healthy donors were stimulated in vitro with conditioned media (CM) derived from the melanoma cell lines SKMEL28 and A375 (melanoma CM), and primary melanocytes as controls. PMN biological properties (chemotaxis, survival, activation, cell tracking, morphology and NET release) were evaluated. We found that the A375 cell line produced soluble factors that promoted PMN chemotaxis, survival, activation and modification of morphological changes and kinetic properties. Furthermore, in both melanoma cell lines CM induced chemotaxis, activation and release of neutrophil extracellular traps (NETs) from PMNs. In contrast, the primary melanocyte CM did not modify the biological behavior of PMNs. In addition, serum levels of myeloperoxidase, matrix metalloprotease-9, CXCL8/IL-8, granulocyte and monocyte colony-stimulating factor and NETs were significantly increased in patients with advanced melanoma compared to healthy controls. Melanoma cell lines produce soluble factors able to “educate” PMNs toward an activated functional state. Patients with metastatic melanoma display increased circulating levels of neutrophil-related mediators and NETs. Further investigations are needed to better understand the role of these “tumor-educated neutrophils” in modifying melanoma cell behavior.
Neurosurgical management of non-spastic movement disorders
Authors: McEvoy Sean D. , Limbrick David D. , Raskin Jeffrey Steven
Published: July 2023

Background

Non-spastic movement disorders in children are common, although true epidemiologic data is difficult to ascertain. Children are more likely than adults to have hyperkinetic movement disorders defined as tics, dystonia, chorea/athetosis, or tremor. These conditions manifest from acquired or heredodegenerative etiologies and often severely limit function despite medical and surgical management paradigms. Neurosurgical management for these conditions is highlighted.

Methods

We performed a focused review of the literature by searching PubMed on 16 May 2023 using key terms related to our review. No temporal filter was applied, but only English articles were considered. We searched for the terms ((“Pallidotomy”[Mesh]) OR “Rhizotomy”[Mesh]) OR “Deep Brain Stimulation”[Mesh], dystonia, children, adolescent, pediatric, globus pallidus, in combination. All articles were reviewed for inclusion in the final reference list.

Results

Our search terms returned 37 articles from 2004 to 2023. Articles covering deep brain stimulation were the most common (n = 34) followed by pallidotomy (n = 3); there were no articles on rhizotomy.

Discussion

Non-spastic movement disorders are common in children and difficult to treat. Most of these patients are referred to neurosurgery for the management of dystonia, with modern neurosurgical management including pallidotomy, rhizotomy, and deep brain stimulation. Historically, pallidotomy has been effective and may still be preferred in subpopulations presenting either in status dystonicus or with high risk for hardware complications. Superiority of DBS over pallidotomy for secondary dystonia has not been determined. Rhizotomy is an underutilized surgical tool and more study characterizing efficacy and risk profile is indicated.
Optical coherence tomography-guided versus angiography-guided percutaneous coronary intervention in acute coronary syndrome: a meta-analysis
Authors: Macherey-Meyer S. , Meertens M. M. , Heyne S. , Braumann S. , Tichelbäcker T. , Wienemann H. , Mauri V. , Baldus S. , Adler C. , Lee S.
Published: July 2023

Background

Percutaneous coronary intervention (PCI) is standard of care in patients with acute coronary syndrome (ACS) suitable for interventional revascularization. Intracoronary imaging by optical coherence tomography (OCT) expanded treatment approaches adding diagnostic information and contributing to stent optimization.

Objectives

This meta-analysis aimed to assess the effects of OCT-guided vs. angiography-guided PCI in treatment of ACS.

Methods

A structured literature search was performed. All controlled trials evaluating OCT-guided vs. angiography-guided PCI in patients with ACS were eligible. The primary end point was major adverse cardiac events (MACE).

Results

Eight studies enrolling 2612 patients with ACS were eligible. 1263 patients underwent OCT-guided and 1,349 patients angiography-guided PCI. OCT guidance was associated with a 30% lower likelihood of MACE (OR 0.70, 95% CI 0.53–0.93, p = 0.01, I2 = 1%). OCT-guided PCI was also associated with significantly decreased cardiac mortality (OR 0.49, 95% CI 0.25–0.96, p = 0.04, I2 = 0%). There was no detectable difference in all-cause mortality (OR 1.08, 95% CI 0.51–2.31, p = 0.83, I2 = 0). Patients in OCT-guided group less frequently required target lesion revascularization (OR 0.26, 95% CI 0.07–0.95, p = 0.04, I2 = 0%). Analysis of myocardial infarction did not result in significant treatment differences. In subgroup or sensitivity analysis the observed advantages of OCT-guided PCI were not replicable.

Conclusion

The evidence suggests that PCI guidance with OCT in ACS decreases MACE, cardiac death and target lesion revascularization compared to angiography. On individual study level, in subgroup or sensitivity analyses these advantages were not thoroughly replicable.
Feasibility and outcome of third-generation transcatheter aortic valve implantation in patients with extra-large aortic annulus
Authors: Hof Alexander , Wienemann Hendrik , Veulemans Verena , Ludwig Sebastian , Rudolph Tanja Katharina , Geißen Simon , Kuhn Elmar , Eghbalzadeh Kaveh , Bleiziffer Sabine , Zeus Tobias , Sedaghat Alexander , Schofer Niklas , Baldus Stephan , Adam Matti , Mauri Victor
Published: July 2023

Background

Many patients in need for transcatheter aortic valve implantation (TAVI) present with an aortic annulus size larger than recommended by the manufacturer’s instructions for use (IFU).

Aims

To investigate procedural and short-term safety and efficacy of TAVI in patients with extra-large annuli (ELA).

Methods

30-day clinical outcome and valve performance as defined by VARC 3 of 144 patients with an aortic annulus size exceeding the permitted range were compared to a propensity-score matched control cohort of patients with an aortic annulus size consistent with the IFU.

Results

Area and perimeter was 730.4 ± 53.9 mm2 and 96.7 ± 6.5 mm in the ELA group. Technical (96.5% vs. 94.4%) and device success (82.3% vs. 84.5%) were comparable in patients with ELA (annulus area 730.4 ± 53.9 mm2) and matched controls (annulus area 586.0 ± 48.2 mm2). There was no significant difference in 30-day mortality rate, major intraprocedural complications, type 3 or 4 bleedings, major vascular complications, or stroke. Moderate paravalvular leakage (PVL) occurred more frequent in the ELA group (8.9% vs 2.2%; p = 0.02). The rate of new pacemaker implantation was 7.0% in the ELA cohort and 15.0% in the control cohort, respectively (p = 0.05).

Conclusion

Treatment of ELA patients with third-generation TAVI prostheses is feasible and safe, providing similar device success and complication rates as in matched controls with regular-sized aortic annulus. Post-interventional pacemaker implantation rates were low compared to the control group, yet incidence of moderate PVL remains problematic in ELA patients.
Spina bifida, the normal, the pathological and the in-between: first evidence from a forensic osteological collection
Authors: Manso Maria Torres , Matos Vitor M. J.
Published: July 2023

Spina bifida (SB), a rare congenital disorder, is often mentioned as an individualizing factor in Forensic Anthropology. A lack of empirical data regarding SB is noticed in the scientific literature. Moreover, within the scope of anthropological research on SB disparities in terminology, classification systems, and methodological approaches result in incomparable results. The wide range (1,2%-50%) of “spina bifida occulta” reported prevalences is a good example. This research aims to analyze and debate the standard diagnostic criteria of SB on human skeletal remains, and attempts to elaborate on an universal system, premised on the distinction between SB as a pathology, and cleft neural arch (CNA) as an anatomical variant, according to Barnes (1994, p. 360 [1). A study-base of 209 individuals (88 males; 121 females; 44–99 years old) from the 21st Century Identified Skeletal Collection from the University of Coimbra (CEI/XXI) was macroscopically analyzed, focusing on the sacrum and remaining vertebrae. Four individuals presented complete posterior opening of the sacral canal (2,6%[4/156]). The observed bone changes, combined with the analysis of the entire skeleton, indicate that CNA, rather than SB linked to a neural tube defect, is the most reliable explanation for these cases. Overall, CNA was observed on 11 skeletons (7.05% of 156). The viability and applicability of the developed methodology for the identification of SB/CNA in forensic and/or osteological contexts are discussed, as well as the possibility of a lower prevalence of SB occulta, in the general population, than speculated before.

Highlights

• Spina bifida has been studied so far under different methodologies, classification systems and nomenclature, leading to unstandardized and incomparable data.

• Spina bifida as a pathological manifestation of a neural tube defect, as opposed to cleft neural arch as a simple form of skeletal variation.

• Both spina bifida and complete sacral cleft fit the criteria of an individualizing trait in Forensic Anthropology.
Acquired bilateral facial palsy: a systematic review on aetiologies and management
Authors: Molinari Giulia , Lucidi Daniela , Fernandez Ignacio Javier , Barbazza Alice , Vanelli Elena , Lami Federico , Federici Gaia , Botti Cecilia , Presutti Livio , D’Angelo Roberto , Rinaldi Rita , Alicandri-Ciufelli Matteo
Published: July 2023

Objective

To systematically review the published cases of bilateral facial palsy (BFP) to gather evidence on the clinical assessment and management of this pathology.

Methods

Following PRISMA statement recommendations, 338 abstracts were screened independently by two authors. Inclusion criteria were research articles of human patients affected by BFP, either central or peripheral; English, Italian, French or Spanish language; availability of the abstract, while exclusion criteria were topics unrelated to FP, and mention of unilateral or congenital FP. Only full-text articles reporting the diagnostic work-up, the management, and the prognosis of the BFP considered for further specific data analysis.

Results

A total of 143 articles were included, resulting a total of 326 patients with a mean age of 36 years. The most common type of the paralysis was peripheral (91.7%), and the autoimmune disease was the most frequent aetiology (31.3%). The mean time of onset after first symptoms was 12 days and most patients presented with a grade higher than III. Associated symptoms in idiopathic BFP were mostly non-specific. The most frequently positive laboratory exams were cerebrospinal fluid analysis, autoimmune screening and peripheral blood smear, and the most performed imaging was MRI. Most patients (74%) underwent exclusive medical treatment, while a minority were selected for a surgical or combined approach. Finally, in more than half of cases a complete bilateral recovery (60.3%) was achieved.

Conclusions

BFP is a disabling condition. If a correct diagnosis is formulated, possibilities to recover are elevated and directly correlated to the administration of an adequate treatment.