bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Gauge for Gravitational Perturbations of Kerr Spacetimes II: The Linear Stability of Schwarzschild Revisited
Authors: Benomio Gabriele
Published: September 2024

We present a new proof of linear stability of the Schwarzschild solution to gravitational perturbations. Our approach employs the system of linearised gravity in the new geometric gauge of Benomio (A new gauge for gravitational perturbations of Kerr spacetimes I: the linearised theory, 2022, https://arxiv.org/abs/2211.00602), specialised to the $$|a|=0$$

|
a
|
=
0

case. The proof fundamentally relies on the novel structure of the transport equations in the system. Indeed, while exploiting the well-known decoupling of two gauge invariant linearised quantities into spin $$\pm 2$$

±
2

Teukolsky equations, we make enhanced use of the red-shifted transport equations and their stabilising properties to control the gauge dependent part of the system. As a result, an initial-data gauge normalisation suffices to establish both orbital and asymptotic stability for all the linearised quantities in the system. The absence of future gauge normalisations is a novel element in the linear stability analysis of black hole spacetimes in geometric gauges governed by transport equations. In particular, our approach simplifies the proof of Dafermos et al. (Acta Math 222:1–214, 2019), which requires a future normalised (double-null) gauge to establish asymptotic stability for the full system.
Utility of pre-procedural [99mTc]TcMAA SPECT/CT Multicompartment Dosimetry for Treatment Planning of 90Y Glass microspheres in patients with Hepatocellular Carcinoma: comparison of anatomic versus [99mTc]TcMAA-based Segmentation
Authors: Lam Marnix , Garin Etienne , Haste Paul , Denys Alban , Geller Brian , Kappadath S. Cheenu , Turkmen Cuneyt , Sze Daniel Y. , Alsuhaibani Hamad Saleh , Herrmann Ken , Maccauro Marco , Cantasdemir Murat , Dreher Matthew , Fowers Kirk D. , Gates Vanessa , Salem Riad
Published: September 2024

Purpose

Pre-treatment [99mTc]TcMAA-based radioembolization treatment planning using multicompartment dosimetry involves the definition of the tumor and normal tissue compartments and calculation of the prescribed absorbed doses. The aim was to compare the real-world utility of anatomic and [99mTc]TcMAA-based segmentation of tumor and normal tissue compartments.

Materials and methods

Included patients had HCC treated by glass [90Y]yttrium microspheres, ≥ 1 tumor, ≥ 3 cm diameter and [99mTc]TcMAA SPECT/CT imaging before treatment. Segmentation was performed retrospectively using dedicated dosimetry software: (1) anatomic (diagnostic CT/MRI-based), and (2) [99mTc]TcMAA threshold-based (i.e., using an activity-isocontour threshold). CT/MRI was co-registered with [99mTc]TcMAA SPECT/CT. Logistic regression and Cox regression, respectively, were used to evaluate relationships between total perfused tumor absorbed dose (TAD) and objective response rate (ORR) and overall survival (OS). In a subset-analysis pre- and post-treatment dosimetry were compared using Bland-Altman analysis and Pearson’s correlation coefficient.

Results

A total of 209 patients were enrolled. Total perfused tumor and normal tissue volumes were larger when using anatomic versus [99mTc]TcMAA threshold segmentation, resulting in lower absorbed doses. mRECIST ORR was higher with increasing total perfused TAD (odds ratio per 100 Gy TAD increase was 1.22 (95% CI: 1.01–1.49; p = 0.044) for anatomic and 1.19 (95% CI: 1.04–1.37; p = 0.012) for [99mTc]TcMAA threshold segmentation. Higher total perfused TAD was associated with improved OS (hazard ratio per 100 Gy TAD increase was 0.826 (95% CI: 0.714–0.954; p = 0.009) and 0.847 (95% CI: 0.765–0.936; p = 0.001) for anatomic and [99mTc]TcMAA threshold segmentation, respectively). For pre- vs. post-treatment dosimetry comparison, the average bias for total perfused TAD was + 11.5 Gy (95% limits of agreement: -227.0 to 250.0) with a strong positive correlation (Pearson’s correlation coefficient = 0.80).

Conclusion

Real-world data support [99mTc]TcMAA imaging to estimate absorbed doses prior to treatment of HCC with glass [90Y]yttrium microspheres. Both anatomic and [99mTc]TcMAA threshold methods were suitable for treatment planning.

Trial registration number

NCT03295006.
Assessing the Implications of Deforestation and Climate Change on Rural Livelihood in Ghana: a Multidimensional Analysis and Solution-Based Approach
Authors: Adom Richard Kwame , Reid Memory , Afuye Gbenga Abayomi , Simatele Mulala Danny
Published: September 2024

The Ashanti region in Ghana, abundant in natural resources such as forests and vegetation biomes, significantly supports the livelihoods of a significant portion of the population. The sustainable management of forest resources remains a significant challenge to achieving environmental and economic growth and poverty alleviation. The study aims to identify the drivers of deforestation and assess its impact on the livelihoods of the poor and vulnerable communities in the Ashanti region. The study utilized qualitative and space-based data to examine the patterns of vegetation cover and deforestation from 2000 to 2020. The results revealed moderate to sparse vegetation in Ashanti from 2002, 2005, 2011, 2015, 2017, and 2018, with no vegetation in the northcentral part, attributed to climate change, agricultural practices, government policies, and deforestation-related disasters. The study found a significant correlation (R² = 0.8197) between years and deforestation areas, especially in 2018 at around 16,000 Sqkm, indicating an exponential increase with severe implications for sustainable livelihoods. Much of these changes were reflected in 2020 with a high peak of deforestation towards the southeastern parts of the region. Additionally, the results show that the poor groups are not passive actors but are actively involved in identifying systems and processes through which to build their adaptive capacity and resilience to environmental and climate change-induced changes. The findings provide evidence-based and all-inclusive approaches that would encourage vulnerable and marginalized groups to participate in the co-production and co-creation of policies and strategies. This outcome is geared towards transformative and sustainable communities while ensuring efficient and effective response and recovery capacities of deforested lands.
Validation of the Swedish Dynamic Imaging Grade of Swallowing Toxicity for Flexible Endoscopic Evaluation of Swallowing (DIGEST-FEES)
Authors: Petersson Kerstin , Finizia Caterina , Pauli Nina , Tuomi Lisa
Published: September 2024

In the head and neck cancer (HNC) population around 45% suffer from chronic swallowing difficulties after cancer treatment. Previously a measure for flexible endoscopic evaluation of swallowing (FEES) where swallowing efficiency, safety and overall ability is evaluated within the same framework has been lacking. The Dynamic Imaging Grade of Swallowing Toxicity for FEES (DIGEST-FEES) was developed in 2021 and provides such a measure for patients with HNC. The aim of this study was to translate and validate the DIGEST-FEES into Swedish (Sw-DIGEST-FEES). A translation of the protocol to Swedish was done through forward-backward translation. Two raters rated eighty-nine FEES recordings according to the Sw-DIGEST-FEES and five reference measures of swallowing ability: Yale Pharyngeal Residue Severity Rating Scale, Swallowing Performance Scale, Murray Secretion Scale, MD Anderson Dysphagia Inventory and Penetration Aspiration Scale. Intra- and interrater reliability was analyzed. Construct validity was evaluated by correlating the Sw-DIGEST-FEES ratings to the reference measures. A priori hypothesis was that the correlations would correspond to those of the reference measures included in the original English version. The Sw-DIGEST-FEES demonstrated retained psychometric properties. Construct validity was good. 79% of correlations to the reference measures were equal to or stronger than those in the original development. Inter-rater agreement of the Sw-DIGEST-FEES ranged from substantial to almost perfect (0.76–0.81). Intra-rater reliability was in general almost perfect (0.8-1). The Sw-DIGEST-FEES can be considered a valid and reliable protocol for use in evaluation of swallowing function in HNC patients.
Genomic characterization of novel viruses associated with Olea europaea L. in South Africa
Authors: Read David A. , Pietersen Gerhard , Slippers Bernard , Steenkamp Emma
Published: September 2024

South Africa has a small but growing olive industry. Until now, no virological research has been carried out on this crop locally. Seventeen samples were collected from various olive cultivars from a single producer in the Stellenbosch growing area of South Africa. RNAseq was performed on total RNA, and the compositions of the metaviromes were determined. Olive leaf yellowing-associated virus was detected for the first time in South Africa, as well as four novel viruses from the family Closteroviridae and one each from the families Tymoviridae and Solemoviridae.
Mechanical and poroelastic behavior of porous tuff under drained and undrained conditions
Authors: Bauer Stephen J. , Broome Scott T. , Kibikas William M. , Wilson Jennifer E.
Published: September 2024

A series of drained and undrained water-saturated constant mean-stress tests were performed to investigate the strength, elasticity, and poroelastic response of a water-saturated high porosity nonwelded tuff. Drained strengths are found to increase with increasing effective confining pressures. Elastic moduli increase with increasing mean stress. Undrained strengths are small due to development of high pore pressures that generate low effective confining pressures. Skempton’s values are pressure dependent and appear to reflect the onset of inelastic deformation. Permeabilities decrease after deformation from ∼ 10–14 to ∼ 10–16 m2 and are a function of the applied confining pressure. Deformation is dominated by pore collapse, compaction, and intense microfracturing, with the undrained tests favoring microfracture-dominant deformation and the drained tests favoring compaction-dominant deformation. These property determinations and observations are used to develop/parameterize physics-based models for underground explosives testing.
Eddy-covariance measurements of turbulent fluxes across the oxygen-depleted benthic layer in a shallow stratified lake
Authors: Kawaguchi Yusuke , Masunaga Eiji , Ouchi Takao , Kitamura Tatsumi , Son Eun Yae
Published: September 2024

Seasonal stratification hinders the ventilation of hypolimnion water, leading to the formation of an anaerobic benthic layer in shallow lakes. This study quantifies the processes of hypoxia formation and recovery in Lake Kasumigaura, Japan, under conditions of developing metalimnion during early summer, specifically from early May to mid-July 2022. We conducted direct observations of vertical turbulent fluxes of dissolved oxygen (DO), as well as heat and momentum fluxes using an eddy-covariance system (ECS), enabling simultaneous measurements of various variables near a sampling volume. Additionally, autonomous acquisition of vertical profiles for DO, temperature, and Chlorophyll a in the lake's vicinity was performed. Our observations revealed that thermal stratification temporarily developed, leading to hypoxia near the bottom when near-surface air temperature exceeded 25 °C. During the metalimnetic period under stable stratification, the ECS demonstrated downward transport of heat and DO, resulting in daily averages of approximately 30–40 W m−2 and 1–1.5 × 10−5 mg L−1 m s−1 (equivalent to 1.1–1.7 mmol m−2 h−1), respectively. Using ECS observations, we estimated a turbulent diffusivity of approximately 5 × 10−6 m2 s−1 during enhanced stratification, consistent with previous reports. Under weak stratification in mid-May, the ECS indicated enhanced vertical fluxes, with occasional upward DO flux. We propose the possibility that phytoplankton acted as oxygen suppliers through photosynthesis activity, promoting vertical DO transfer.
Strategic investment in power generation and transmission under a feed-in premium scheme: a game theoretic real options analysis
Authors: Ito Kazuya , Tanaka Makoto , Takashima Ryuta
Published: September 2024

The spread of renewable energy has been accelerated by investment in power generation and transmission systems under environmental policy support such as a feed-in premium (FIP) scheme. This study examines the decision-making of the transmission system operator (TSO) and the power generation company (GENCO), where the TSO maximizes social surplus by investing in transmission lines, and the GENCO maximizes its profit by investing in power generation facilities. Specifically, the TSO decides the investment timing, while the GENCO decides the capacity. We develop a real options model to analyze the equilibrium investment timing and capacity under uncertainties in a framework of game between TSO and GENCO. We consider several scenarios in which the GENCO invests in non-renewable energy (NRE); invests in renewable energy (RE) with FIP; and invests in RE with its installation cost reduction. Our results indicate that FIP and the installation cost reduction of RE affect the equilibrium decision in a different manner. We find that FIP tends to be more welfare-enhancing than the reduction of RE installation cost when the degree of uncertainty is larger. We also demonstrate that social surplus can be increased without FIP if the installation cost of RE is reduced sufficiently in the future.
Assessment of genetic diversity in a locally endangered tern species suggests population connection instead of isolation
Authors: Schnelle Anna , Rollins Robert E. , Cecere Jacopo G. , Serra Lorenzo , Gutiérrez Jorge S. , Masero Jose A. , Risch Markus , Bouwhuis Sandra , Liedvogel Miriam
Published: September 2024

Many bird populations are declining globally, with migratory sea- and waterbirds among the most threatened groups. Increased isolation between populations, due to habitat loss leading to limited connectivity and reduced gene flow, may accelerate population declines or even cause local extinctions. To address this threat and inform conservation efforts, assessment of the genetic diversity of endangered populations is required. In Central Europe, gull-billed terns (Gelochelidon nilotica) have experienced a severe population decline in the past century, with only one last population of c. 40 breeding pairs remaining. Here, we aimed to characterise the genetic diversity of this population, and to compare it to that of two separate Mediterranean colonies to assess potential population connectivity. To achieve this, we developed a PCR protocol to amplify and sequence the complete mitochondrial genome (mtDNA). We found high genetic diversity in all three populations, and no population structure based on breeding location, as well as moderate population differentiation between Germany and Italy, and low differentiation between Germany and Spain, and between Italy and Spain. The German population, however, showed signs of population restriction, while both Mediterranean colonies showed evidence for population expansion. These results indicate that the last population of gull-billed terns in Central Europe is not acutely threatened by loss of genetic diversity, but instead shows signs of connectivity with other European colonies, which in turn suggests that conservation efforts should best focus on habitat and predation management.
The Role of Political Ideology in Agreement with Prisoner Responsibility for Personal Safety and Well-Being
Authors: Hansen Michael A. , Navarro John C.
Published: September 2024

Although the United States leads the world in its imprisonment rate, an investigation of American public attitudes toward the safety and well-being of prisoners has not kept pace. In a survey distributed via Mechanical Turk (MTurk) (n = 979), the authors explore how respondents’ political ideology influences their views on seven specific aspects of prison conditions related to prisoners’ self-defense and responsibility for their safety, including physical and sexual assaults, as well as acceptance of poor prison conditions. Political ideology is a large and significant predictor of opinions on these seven aspects of prisoner safety and wellness. Conservatives are more likely than liberals to agree with statements supporting harsher prison conditions. While political ideological gaps are wide, these gaps narrow on statements regarding the expectations of prisoners to defend themselves from physical and sexual assault. These findings add insight into how ideological attitudes may influence justice-related decisions on prison life and punishment for prisoners.
Student approaches to generating mathematical examples: comparing e-assessment and paper-based tasks
Authors: Kinnear George , Iannone Paola , Davies Ben
Published: September 2024

Example-generation tasks have been suggested as an effective way to both promote students’ learning of mathematics and assess students’ understanding of concepts. E-assessment offers the potential to use example-generation tasks with large groups of students, but there has been little research on this approach so far. Across two studies, we investigate students’ responses to a particular sequence of example-generation tasks, posed either on paper or through e-assessment. We identify a striking difference in students’ example-generation strategies and success, for e-assessment and paper-based versions of the same tasks. This suggests the use of example-generation tasks in e-assessment may not be straightforward, and we conclude by discussing the implications for teaching and research.
Combining Probabilities with Full Beliefs
Authors: Hansson Sven Ove
Published: September 2024

One of the major problems in formal epistemology is the difficulty of combining probabilistic and dichotomous (all-or-nothing) beliefs in one and the same formal framework. Based on the properties of actual human belief systems, a set of ten desiderata is proposed for belief system models that contain both probabilistic and full beliefs. Previously proposed combined belief systems are shown to fall short of these desiderata. A proof of concept is provided to show that they can be satisfied in a formal model. In the proposed model, the amnesia problem of probabilistic updating is solved by introducing infinitesimal probabilities as carriers of memories of beliefs that have been given up. In the resulting system of probability revision, contingent propositions can be transferred in both directions between full beliefs and beliefs held to a lower degree, in a way that mirrors real-life acquisitions and losses of full beliefs. The subsystem consisting of full beliefs has a pattern of change that constitutes a credible system of dichotomous belief change.
The value of laws in chemistry
Authors: Seifert Vanessa A.
Published: September 2024

In philosophy, the empirical success of a science is often explained by the fact that it has managed to discover some law(s) of nature. This line of thought has not been thoroughly explored with respect to chemistry. The aim of this paper is to fill this gap by showing how we could think about laws in chemistry. Specifically, it briefly presents how laws of nature are understood in philosophy of science. It then discusses two case studies from chemistry—the periodic table and chemical reactions—and explains how general ideas about law-hood can be applied to these cases. Lastly, it presents research questions and philosophical problems that arise by considering chemistry from the perspective of laws. This analysis illustrates that there is value in thinking about laws in chemistry.
Gestures as Archives: Truth, Loss, and Resistance
Authors: Popa Delia
Published: September 2024

In this paper, I develop a phenomenological investigation of gestures that focuses on their temporal formation and their historical sedimentation. My approach combines a genetic phenomenological analysis with psychoanalytic investigations, to elaborate on the idea of an archeology of gestures that explores the hidden historicity of their fugitive expression and the consistent patterns of their bodily manifestation. The paper examines four aspects of gestures—hovering, exhibition, mimesis, and resistance—in order to question their relationship to truth. In the last part of the paper, I explore the role of gestures in difficult processes of mourning and melancholia, focusing on the somatic incorporation of a lost other in oneself. In the light of these analyses, I propose to consider gestures as bodily archives that speak for cryptic inscriptions of past experiences, whose role is to keep alive a past that we cannot let go but also for emancipatory transitions toward new horizons, where the sense of our experience can finally be conquered as our own.
Assessing Organizations as Responsible Entities Adequately. A Practice-Based Approach to Organizational Agency
Authors: Jungmann Robert
Published: September 2024

In complex settings, organizations overlap with other collective entities in time and space even as they struggle for visibility or invisibility as relevant entities. Moreover, they do not act as legal persons or complete organizational actors all the time. Such settings give rise to a question that bears on the fundamental question of adequately identifying and assessing causal forces in social processes, namely: Who or what is responsible here? Where personal experiences, organizational and network dynamics, and large-scale societal forces seem to work together efficiently and without friction, the task of analyzing an organization as a singular collective instance with causal power driving a series of events is met with formidable challenges. I propose a practice-based framework on organizational agency to address such analytical issues and distinguish between three forms, namely organizational interventions, stable organizations, and competent organizational actors. Each of these three types differs in how to assess organizational agency and its constitution. To conclude, I call for a distinct sociological stance for answering questions of collective causation and responsibility in debates over legal liability in digitalized spheres and corporate or political responsibilities for large-scale social challenges, like sustainable transitions. This stance differs from Weberian roots, in that it neither preconditions formal procedures nor a collective actor. A case study of a scientific project network discovering catalytic mechanisms in producing hydrogen to drive a sustainable energy transition illustrates the analytical value of this framework.
Augmented Reality to Assist in the Diagnosis of Temporomandibular Joint Alterations
Authors: Cercenelli Laura , Emiliani Nicolas , Gulotta Chiara , Bevini Mirko , Badiali Giovanni , Marcelli Emanuela
Published: September 2024

Augmented Reality (AR) is an increasingly prominent technology with diverse applications across various surgical disciplines. This study aims to develop and assess the feasibility of a novel AR application intended to aid surgeons in the clinical assessment of temporomandibular joint (TMJ) alterations necessitating surgical intervention. The application employs a multi-modality tracking approach, combining both marker-less and marker-based tracking techniques to concurrently track the fixed portion of the joint and the movable mandible involved in TMJ. For the marker-based tracking both a planar marker with a binary QR-code pattern and a cuboid marker that contains a unique QR-code pattern on each face were tested and compared. The AR application was implemented for the HoloLens 2 head-mounted display and validated on a healthy volunteer performing the TMJ task, i.e. the opening and closing of the mouth. During the task, video recordings from the HoloLens cameras captured the horizontal and vertical excursions of the jaw movements (TMJ movements) using virtual markers anchored to the AR-displayed virtual anatomies. For validation, the video-recorded TMJ movements during AR viewing were compared with standard kinesiographic acquisitions. The findings demonstrated the consistency between the AR-derived trajectories and the kinesiography curves, especially when using the cubic Multi Target tracker to follow the moving mandible. Finally, the AR application was experienced on a patient and it was extremely useful for the surgeon to diagnose alterations in the normal kinematics of the TMJ. Future efforts should be addressed to minimize the bulkiness of the tracker and provide additional visual cues for surgeons.
A Longitudinal Study of Aggression in People with Autism and Other Neurodevelopmental Disabilities
Authors: Gohari Dena , Schiltz Hillary , Lord Catherine
Published: September 2024

Aggression is common in autism and neurodevelopmental disorders, but longitudinal research on aggression is lacking. We longitudinally tracked aggression in 254 individuals from toddlerhood to emerging adulthood. Our sample included participants with a range of cognitive abilities, with 39.9% classified as more-cognitively-abled (MCA; IQ ≥ 70) and 60.1% as less-cognitively-abled (LCA; IQ < 70). Aggression Composite scores were derived from data from the autism diagnostic observation schedule, autism diagnostic interview-revised, and child behavior checklist at ages 2, 9, and 18. Fifty-four percent, 69%, and 42% of the sample showed aggression in toddlerhood, school age, and emerging adulthood, respectively. LCA individuals had higher rates of aggression in school age (80%) and emerging adulthood (58%) compared to MCA individuals (48 and 22%, respectively). Longitudinal aggression profiles revealed distinct patterns of change over time: 31% displayed persistent aggression, 25% increased, 23% decreased, and 13% never displayed aggression. Higher autism symptoms, lower VIQ, NVIQ, and less-developed adaptive skills correlated with more aggression cross-sectionally. Nonverbal IQ and repetitive behaviors related to aggression longitudinally: people in decreasing or absent profiles had higher NVIQ and fewer RRBs than those with persistent or increasing profiles. Participants with aggression at 9 were four times likelier to exhibit aggression at 18. Aggression is common in autism and NDDs, peaking around age 9, and declining in emerging adulthood. Patterns of change varied widely, with evidence that higher NVIQ and fewer RRBs may be protective. Findings have implications for clinical practices, highlighting important developmental periods and high-risk subgroups.
Error Estimates for First- and Second-Order Lagrange–Galerkin Moving Mesh Schemes for the One-Dimensional Convection–Diffusion Equation
Authors: Putri Kharisma Surya , Mizuochi Tatsuki , Kolbe Niklas , Notsu Hirofumi
Published: September 2024

A new moving mesh scheme based on the Lagrange–Galerkin method for the approximation of the one-dimensional convection–diffusion equation is studied. The mesh movement is prescribed by a discretized dynamical system for the nodal points. This system is related to the velocity and diffusion coefficient in the convection–diffusion equation such that the nodal points follow the convective flow of the model. It is shown that under a restriction of the time step size the mesh movement cannot lead to an overlap of the elements and therefore an invalid mesh. Using a piecewise linear approximation, optimal error estimates in the $$\ell ^\infty (L^2) \cap \ell ^2(H_0^1)$$

ℓ
∞

(

L
2

)

∩

ℓ
2

(

H
0
1

)

norm are proved in case of both, a first-order backward Euler method and a second-order two-step method in time. These results are based on new estimates of the time dependent interpolation operator derived in this work. Preservation of the total mass is verified for both choices of the time discretization. Numerical experiments are presented that confirm the error estimates and demonstrate that the proposed moving mesh scheme can circumvent limitations that the Lagrange–Galerkin method on a fixed mesh exhibits.
Linguistic reconciliation in contexts of conflict: Tamil language learning in Sri Lanka
Authors: Perera Nirukshi , Khodos Iryna
Published: September 2024

This article explores how language learning is an integral component of progressing linguistic reconciliation in contexts of war and conflict. Sri Lanka is a case where ethnolinguistic division and the devaluation of Tamil as a co-official language has led to linguistic injustice for Tamil people and users of Tamil. In the post-war landscape, government commitment towards addressing this injustice, and reconciliation for that matter, has been weak. We interviewed 12 adult students and teachers in a small, non-profit, Tamil language course to understand what motivates people to learn Tamil in this context. The language course was a space where both second language and heritage language learners came together. Thematic analysis of the interview data showed that language learning motivations extended beyond the norm of the instrumental/integrative dichotomy and revealed the role of social, historical, and political factors, and a shared vision for societal multilingualism in shaping learners’ motivations. The results help to form a preliminary conceptualisation of linguistic reconciliation and to promote language learning “of the enemy” as an integral and impactful component.
Disuse atrophy of articular cartilage can be restored by mechanical reloading in mice
Authors: Nomura Masato , Moriyama Hideki , Wakimoto Yoshio , Miura Yasushi
Published: September 2024

Background

Moderate mechanical stress generated by normal joint loading and movements helps maintain the health of articular cartilage. Despite growing interest in the pathogenesis of cartilage degeneration caused by reduced mechanical stress, its reversibility by mechanical reloading is less understood. This study aimed to investigate the response of articular cartilage exposed to mechanical reloading after unloading in vivo and in vitro.

Methods and results

Disuse atrophy was induced in the knee joint cartilage of adult mice through hindlimb unloading by tail suspension. For in vivo experiments, mice were subjected to reloading with or without daily exercise intervention or surgical destabilization of the knee joint. Microcomputed tomography and histomorphometric analyses were performed on the harvested knee joints. Matrix loss and thinning of articular cartilage due to unloading were fully or partially restored by reloading, and exercise intervention enhanced the restoration. Subchondral bone density decreased by unloading and increased to above-normal levels by reloading. The severity of cartilage damage caused by joint instability was not different even with prior non-weight bearing. For in vitro experiments, articular chondrocytes isolated from the healthy or unloaded joints of the mice were embedded in agarose gel. After dynamic compression loading, the expression levels of anabolic (Sox9, Col2a1, and Acan) and catabolic (Mmp13 and Adamts5) factors of cartilage were analyzed. In chondrocytes isolated from the unloaded joints, similar to those from healthy joints, dynamic compression increased the expression of anabolic factors but suppressed the expression of catabolic factors.

Conclusion

The results of this study indicate that the morphological changes in articular cartilage exposed to mechanical unloading may be restored in response to mechanical reloading by shifting extracellular matrix metabolism in chondrocytes to anabolism.
Spatial patterns and effects of invasive plants on soil microbial activity and diversity along river corridors
Authors: Gömöryová Erika , Hrivnák Richard , Galvánek Dobromil , Kochjarová Judita , Skokanová Katarína , Slezák Michal , Svitková Ivana , Šingliarová Barbora , Španiel Stanislav , Gömöry Dušan
Published: September 2024

Background and aims

Invasive species represent a threat to the conservation of biological systems. Riparian ecosystems are vulnerable to plant invasions, as waterflow facilitates the dispersal of plant propagules, while invasive species may subsequently impact soil, including soil microbial communities. Downstream connectivity among disparate riverine segments is expected to cause spatial continuity of abiotic and biotic components of riparian ecosystems.

Methods

We studied diversity of microbial communities in three headwater streams in Central Europe. Plant diversity, soil properties and soil microbiota were assessed on 20 sample plots per river. Soil microbial activity and community-level physiological profiling were used to study the soil microbial community.

Results

While the α-diversity of plants and soil microbiota was similar among rivers, plant communities were substantially more differentiated than microbial communities. Richness in alien and invasive plants significantly differed among rivers, which was reflected in different spatial patterns of microbial activity and diversity. A high level of spatial continuity was observed in the Kysuca river with straightened riverbed and artificial surfaces in the adjacent areas. The cover of invasive plants affects the composition of microbial functional groups of riverbed soils.

Conclusion

The expectation of spatial continuity of riverbed soil properties including those of soil microbiota caused by connectivity between different river segments was only partially fulfilled. Spatial continuity strongly depends on the environmental setting and stream characteristics of a particular river. The presence of invasive herbs affected the functional composition of soil microbiota but had no effect on microbial activity and diversity.
Political Normativity… All-Things-Considered
Authors: Testini Francesco
Published: September 2024

The idea of a distinctively political normativity came under sustained fire lately. Here I formulate, test, and reject a moderate and promising way of conceiving it. According to this conception, political normativity is akin to the kind of normativity at play in all-things-considered judgments, i.e., those judgments that weight together all the relevant reasons to determine what practical rationality as such requires to do. I argue that even when we try to conceive political normativity in this all-things-considered way, and even when we do not concede from the get-go that moral reasons necessarily trump or override normative reasons of a different kind, political normativity is still reducible to morality, because the peculiar content of all-things-considered political oughts can be explained by the interplay of general moral principles and contextual facts that do not obtain exclusively in political scenarios. If my arguments are correct, I provide political realists with one more reason to withdraw from the metaethical battle over the idea of a distinctively political normativity and show that the moralist approach is defensible against a prima facie promising, but ultimately untenable, alternative.
Immunohistochemical Evaluation of Cathepsin B, L, and S Expression in Breast Cancer Patients
Authors: Linders Daan G. J. , Bijlstra Okker D. , Fallert Laura C. , Dekker-Ensink N. Geeske , March Taryn L. , Pool Martin , Walker Ethan , Straight Brian , Basilion James P. , Bogyo Matthew , Burggraaf Jacobus , Hilling Denise E. , Vahrmeijer Alexander L. , Kuppen Peter J. K. , Crobach A. Stijn L. P.
Published: September 2024

Purpose

Cysteine cathepsins are proteases that play a role in normal cellular physiology and neoplastic transformation. Elevated expression and enzymatic activity of cathepsins in breast cancer (BCa) indicates their potential as a target for tumor imaging. In particular cathepsin B (CTSB), L (CTSL), and S (CTSS) are used as targets for near-infrared (NIR) fluorescence imaging (FI), a technique that allows real-time intraoperative tumor visualization and resection margin assessment. Therefore, this immunohistochemical study explores CTSB, CTSL, and CTSS expression levels in a large breast cancer patient cohort, to investigate in which BCa patients the use of cathepsin-targeted NIR FI may have added value.

Procedures

Protein expression was analyzed in tumor tissue microarrays (TMA) of BCa patients using immunohistochemistry and quantified as a total immunostaining score (TIS), ranging from 0–12. In total, the tissues of 557 BCa patients were included in the TMA.

Results

CTSB, CTSL, and CTSS were successfully scored in respectively 340, 373 and 252 tumors. All tumors showed CTSB, CTSL, and/or CTSS expression to some extent (TIS > 0). CTSB, CTSL, and CTSS expression was scored as high (TIS > 6) in respectively 28%, 80%, and 18% of tumors. In 89% of the tumors scored for all three cathepsins, the expression level of one or more of these proteases was scored as high (TIS > 6). Tumors showed significantly higher cathepsin expression levels with advancing Bloom-Richardson grade (p < 0.05). Cathepsin expression was highest in estrogen receptor (ER)-negative, human epidermal growth factor receptor 2(HER2)-positive and triple-negative (TN) tumors. There was no significant difference in cathepsin expression between tumors that were treated with neoadjuvant systemic therapy and tumors that were not.

Conclusions

The expression of at least one of the cysteine cathepsins B, L and S in all breast tumor tissues tested suggests that cathepsin-activatable imaging agents with broad reactivity for these three proteases will likely be effective in the vast majority of breast cancer patients, regardless of molecular subtype and treatment status. Patients with high grade ER-negative, HER2-positive, or TN tumors might show higher imaging signals.
Curriculare Implementierung der Profillinie Patientensicherheit in den Studiengang Humanmedizin – formative und summative Evaluationsergebnisse für den ersten und zweiten Studienabschnitt
Authors: Petzina Rainer , Heese Oliver , Marung Hartwig , Wehkamp Kai , Wulfhorst Britta , Lichtenauer Urs , Brünahl Christian
Published: September 2024

Hintergrund und Zielstellung

Der Masterplan Medizinstudium 2020 hat grundlegende Veränderungen in der medizinischen Ausbildung angestoßen. Nachdem das Themenfeld Patientensicherheit verstärkt in dem Nationalen Kompetenzbasierten Lernzielkatalog Medizin (NKLM) 2.0 verankert wurde und deutlich an Relevanz gewonnen hat, stellen wir den aktuellen Stand der curricularen Implementierung der Profillinie Patientensicherheit im Studiengang Humanmedizin an der MSH Medical School Hamburg (MSH) vor. Ziel ist es, zum einen darzustellen, wie die Profillinie Patientensicherheit in den Studiengang Humanmedizin an der MSH als integriertes longitudinales Curriculum implementiert wird sowie zum anderen die formativen und summativen Evaluationsergebnisse zu präsentieren.

Methode

Zunächst erfolgte eine Recherche der aktuellen Literatur, ein Screening der Homepages der medizinischen Fakultäten und darauf aufbauend ein interdisziplinärer Expert:innenaustausch. Auf dieser Grundlage wurde konsentiert die Profillinie Patientensicherheit in allen drei Studienabschnitten zu implementieren. Dies wird kontinuierlich durch die routinemäßigen Semesterbewertungen der Studierenden zur Qualitätssicherung und durch summative Prüfungen evaluiert. Zusätzlich erfolgen formative Evaluationen der Lehr‑/Lernveranstaltungen während des Semesters.

Ergebnisse

Die Ergebnisse der Literaturrecherche, des Screenings der Homepages der medizinischen Fakultäten und der Expert:innenaustausche bestätigen den zunehmenden Stellenwert von Patientensicherheit in der medizinischen Ausbildung. Daraufhin wurden die im NKLM 2.0 verankerten Kompetenzen und Lernziele zur Patientensicherheit longitudinal in den Studiengang Humanmedizin an der MSH curricular implementiert. Seit dem Sommersemester 2023 finden in den ersten beiden Studienabschnitten entsprechende Vorlesungen inklusive MC-Prüfungen, Seminare, Wahlmodule und OSCE-Prüfungen (Objective Structured Clinical Examination) zum Thema Patientensicherheit statt. Die ersten formativen und summativen Evaluationsergebnisse der Studierenden sind sehr vielversprechend und ab dem Wintersemester 2024 werden die ersten MSH-Studierenden im dritten Studienabschnitt ein Patientensicherheitssimulationstraining absolvieren.

Schlussfolgerung

Die Implementierung der Profillinie Patientensicherheit als integriertes longitudinales Curriculum in den Studiengang Humanmedizin in allen drei Studienabschnitten stellt eine große Herausforderung und dringende Erfordernis dar. Durch die Implementierung wird das für alle Querschnittsbereiche relevante Thema Patientensicherheit umfassend und nachhaltig abgebildet.
The Effect of Platelet Dose on Outcomes after Platelet Rich Plasma Injections for Musculoskeletal Conditions: A Systematic Review and Meta-Analysis
Authors: Berrigan William , Tao Frances , Kopcow Joel , Park Anna L. , Allen Isabel , Tahir Peggy , Reddy Aakash , Bailowitz Zachary
Published: September 2024

Purpose of Review

This study aims to systematically review platelet dosage in platelet rich plasma (PRP) injections for common musculoskeletal conditions.

Recent Findings

Notable heterogeneity exists in the literature regarding platelet dosage. Clinical studies indicate that a higher dosage may lead to improved outcomes concerning pain relief, functional improvement, and chondroprotection in knee osteoarthritis (OA). However, the impact of dosing on other musculoskeletal pathologies remains uncertain. Our investigation identifies a potential dose-response relationship between platelet dose and PRP effectiveness for knee OA treatment, pinpointing an optimal threshold of greater than 10 billion platelets for favorable clinical outcomes. Notably, this effect appears more pronounced for functional outcomes than for pain relief. For other conditions, a lower dosage may suffice, although the existing literature lacks clarity on this matter.

PRP dosage may significantly influence treatmentoutcomes, particularly in knee OA. Further research is warranted to elucidate optimal dosages for varying conditions.
Relationship between hemoglobinopathies and male infertility: a scoping review
Authors: Al-Jubouri Abdullah M. , Eliwa Ahmed , Haithm Yunes , Al-Qahtani Noof , Jolo Lolwa , Yassin Mohamed
Published: September 2024

Infertility is a common issue that threatens couples worldwide. Infertility can result from the male or female partner alone, or both partners. It can be due to multiple factors related to the patient’s overall health or lifestyle. Causes related to patient health can be systemic or related to gonadal dysfunction. One of the systematic causes can be hematological. The two most common hemoglobinopathies that are thought to cause infertility, especially male infertility, are sickle cell disease (SCD) and thalassemia major (TM). These two hemoglobinopathies cause male infertility through pathophysiological alterations. Specifically, they alter the oxygen carrying ability of red blood cells (RBCs), causing tissue hypoxia that affects the normal physiological process of spermatogenesis, eventually inducing infertility. Semen analyses and other systemic blood testing can be used to investigate male infertility. Both hemoglobinopathies can be helped by blood transfusions, which can then alleviate male infertility. This paper aims to explore the relationship between hemoglobinopathies (SCD and TM) and their role in contributing to male infertility, in addition to the role of blood transfusions in addressing male infertility by correcting the root cause.
An User-Centered Evaluation of Two Socially Assistive Robots Integrated in a Retirement Home
Authors: Jerez Antonio , Iglesias Ana , Pérez-Lorenzo José Manuel , Tudela Alberto , Cruces Alejandro , Bandera Juan Pedro
Published: September 2024

Socially assistive robots are receiving a growing interest in the health and social care sectors. They are considered a promising technology to add value to the work of caregivers, and relieve them of simple and repetitive tasks. However, these robots currently face significant difficulties when deployed in everyday scenarios due to a number of factors. Most of these factors are related to insufficient consideration of the user perspective and incorrect evaluation procedures. This paper aims to address these issues. Its objective is to analyze the long-term accessibility, usability, social acceptance and user experience for two different socially assistive robots performing the same tasks in a retirement home. The evaluation procedure is based on a framework specifically designed to consider these criteria. Collected results show that both robots received an overall positive feedback. Although the number of users participating in the evaluation was not very high, due to the chosen recruitment criteria and the period of activity of this research project, during the COVID19 pandemic, these results allow to extract relevant insights towards a meaningful use of social robots in shared social care contexts.
Stuck in the middle with you: Conceptualizing data intermediaries and data intermediation services
Authors: Schweihoff Julia , Lipovetskaja Anzelika , Jussen-Lengersdorf Ilka , Möller Frederik
Published: September 2024

Data intermediation services are a novel class of services mitigating various aspects of inter-organizational data sharing. Facilitating data intermediation services is a pivotal activity that leverages the benefits of the data economy. These services are usually provided by so-called data intermediaries, who organize data sharing between one or multiple data provider(s) and data consumer(s). Against the background of prominent legislation, these data intermediaries (e.g., data marketplaces or data trusts) receive increasing attention in research, practice, and politics. For instance, the Data Governance Act regulates data intermediation services, prompting organizations sharing data to comply with various regulations, including registration with government bodies or acquiring a trusted label. However, to date, little research has been done about the nature of data intermediation services, motivating us to tackle this issue in a two-fold strategy. First, we derive a visualization of a data intermediary and concept subsuming its potential functions. Second, we explore archetypical configurations of co-existing services of data intermediaries. With this, we contribute to understanding the data intermediaries as a concept and enrich this understanding with more detailed service configurations.
Wie entwickelt sich mathematikspezifische diagnostische Kompetenz von Studierenden des Grundschullehramts?
Authors: Dingemans Steffen
Published: September 2024

Der Erfolg eines individualisierten Mathematikunterrichts hängt wesentlich davon ab, dass Lehrerinnen und Lehrer den individuellen Lernstand und die Lösungswege von Kindern im Unterricht schnell und sicher diagnostizieren und daraus gezielte Hilfen und Förderansätze entwickeln können. Allerdings deuten Studien darauf hin, dass die diagnostische Kompetenz von Mathematiklehrkräften nicht ausreichend ausgebildet ist. Im Rahmen des Praxissemesters als Teil der praxisorientierten Ausbildung von angehenden Lehrkräften sollte es daher auch Ziel sein, ihre diagnostische Kompetenz fachspezifisch zu entwickeln.

Konkret wird in der zugrundeliegenden Studie untersucht, inwieweit sich die mathematikspezifische diagnostischen Kompetenz von Grundschullehramtsstudierenden im Praxissemester entwickelt. Dies beinhaltet den Vergleich der Vorbereitungsphase an der Universität mit der anschließenden Praxisphase in den Schulen. Den Kern der als mixed-method angelegten längsschnittlichen Evaluation stellen vier Videovignetten dar. Die Studierenden (N = 53) wurden in einer Online-Umfrage mit offenen Antwortformaten aufgefordert, die Lösungswege von Kindern zur Addition und Subtraktion im Zahlenraum bis 100 fachlich angemessen zu analysieren.

Die quantitative Auswertung zeigt eine signifikante Verbesserung der diagnostischen Kompetenz innerhalb der universitären Vorbereitungsphase. In der Praxisphase selbst ist allerdings eine leicht negative Entwicklung zu verzeichnen. Insgesamt kann im einjährigen Praxissemester daher lediglich eine positive Entwicklungstendenz festgestellt werden. Zudem wird die Bedeutsamkeit eines spezifischen fachdidaktischen Wissens für das Gelingen handlungsleitender Diagnostik im Fach Mathematik von den vorliegenden Ergebnissen gestützt.