bluuebunny/crossref_metadata_2025 huggingface dataset:
Hic sunt leones. User orientation as a design principle for emerging institutions on social media platforms
Authors: Marin Lavinia , Vică Constantin
Published: April 2024

The phenomenon of missed interactions between online users is a specific issue occurring when users of different language games interact on social media platforms. We use the lens of institutional theory to analyze this phenomenon and argue that current online institutions will necessarily fail to regulate user interactions in a way that creates common meanings because online institutions are not set up to deal with the multiplicity of language games and forms of life co-existing in the online social space. We argue for the need to enable and foster grassroots online institutions that can stabilize the norms of interaction by redesigning algorithms and user interfaces. Such online grassroots institutions would facilitate user orientation at three distinct levels: informational, normative, and semantic-pragmatic. We propose user orientation as a principle that would facilitate the formation of institutions aiming to regulate information exchanges between users inhabiting various forms of life. This principle of user orientation should guide design decisions, while designer teams would need to become aware of the institutional power unleashed when they set up interfaces and algorithms for user-generated content.
Development of polymer/carbon nanotubes incorporated sustainable materials for manufacturing of autobrake pad
Authors: Orji Uyor Uwa , Patricia Popoola Abimbola , Sunday Aigbodion Victor , Olawale Popoola
Published: April 2024

Although asbestos fiber is used for autobrake pad production due to its heat resistance capacity, it is associated with a challenge of health risk (cancerogenic in nature). This health risk associated with asbestos-based autobrake pads has presented polymeric materials as a better candidate for the application due to their eco-friendliness, lightweight, chemical inertness, easy of processing, etc. However, polymers are associated with low wear and low mechanical properties, which are vital properties for autobrake pads. Therefore, this study developed EP nanocomposites reinforced with a low content of carbon nanotubes (CNTs) and eggshell (ES) attached cow bone (CB) particles denoted as (ES@CB) as agro-waste/sustainable materials for the manufacturing of autobrake pads. The hybrid ternary nanocomposites were developed via solution mixing and casting. Scanning electron microscope (SEM) revealed the 1-D structure of the CNTs, and relatively spherical shapes of ES and CB particles, and microstructures of the developed nanocomposites. The nanocomposite showed a low coefficient of friction and a reduction in wear rate in the range of 1.14 × 10−4 mm3/Nm for pure EP to 5.45 × 10−6 mm3/Nm for EP/0.4wt%CNTs-10wt%ES@CB nanocomposite, while the elastic modulus and hardness increased from 1.84 GPa and 128.64 MPa for pure EP to 4.41 GPa and 252.88 MPa for EP/0.2wt%CNTs-20wt%ES@CB nanocomposite, respectively. The comparison of the wear response of the developed nanocomposites with the current asbestos-based brake pads show that the developed epoxy nanocomposites from agro-waste materials are potential option for the manufacturing of autobrake pads, which will ensure sustainability, health risk-free, and environmentally friendly.
Computing perfect stationary equilibria in stochastic games
Authors: Li Peixuan , Dang Chuangyin , Herings P. Jean-Jacques
Published: April 2024

The notion of stationary equilibrium is one of the most crucial solution concepts in stochastic games. However, a stochastic game can have multiple stationary equilibria, some of which may be unstable or counterintuitive. As a refinement of stationary equilibrium, we extend the concept of perfect equilibrium in strategic games to stochastic games and formulate the notion of perfect stationary equilibrium (PeSE). To further promote its applications, we develop a differentiable homotopy method to compute such an equilibrium. We incorporate vanishing logarithmic barrier terms into the payoff functions, thereby constituting a logarithmic-barrier stochastic game. As a result of this barrier game, we attain a continuously differentiable homotopy system. To reduce the number of variables in the homotopy system, we eliminate the Bellman equations through a replacement of variables and derive an equivalent system. We use the equivalent system to establish the existence of a smooth path, which starts from an arbitrary total mixed strategy profile and ends at a PeSE. Extensive numerical experiments, including relevant applications like dynamic oligopoly models and dynamic legislative voting, further affirm the effectiveness and efficiency of the method.
Determination of calcium, iron, and selenium in human serum by isotope dilution analysis using nitrogen microwave inductively coupled atmospheric pressure plasma mass spectrometry (MICAP-MS)
Authors: You Zengchao , Winckelmann Alexander , Vogl Jochen , Recknagel Sebastian , Abad Carlos
Published: April 2024

In this study, we demonstrate the applicability of nitrogen microwave inductively coupled atmospheric pressure mass spectrometry (MICAP-MS) for Ca, Fe, and Se quantification in human serum using isotope dilution (ID) analysis. The matrix tolerance of MICAP-MS in Na matrix was investigated, revealing that high Na levels can suppress the signal intensity. This suppression is likely due to the plasma loading and the space charge effect. Moreover, 40Ca and 44Ca isotopic fractionation was noted at elevated Na concentration. Nine certified serum samples were analyzed using both external calibration and ID analysis. Overestimation of Cr, Zn, As, and Se was found in the results of external calibration, which might result from C-induced polyatomic interference and signal enhancement, respectively. Further investigations performed with methanol showed a similar enhancement effect for Zn, As, and Se, potentially supporting this assumption. The mass concentrations determined with ID analysis show metrological compatibility with the reference values, indicating that MICAP-MS combined with ID analysis can be a promising method for precise Ca, Fe, and Se determination. Moreover, this combination reduces the influence of matrix effects, broadening the applicability of MICAP-MS for samples with complex matrixes.

Graphical abstract
Atmospheric pressure field desorption-trapped ion mobility-mass spectrometry coupling
Authors: Gross Jürgen H.
Published: April 2024

While field ionization (FI) and field desorption (FD) are established soft vacuum ionization methods in mass spectrometry (MS), the technique of atmospheric pressure field desorption (APFD) has only recently been added to the repertoire. Similar to FI and FD, APFD can yield both positive even-electron ions of highly polar or ionic compounds and positive molecular ions, M+•, e.g., of polycyclic aromatic compounds. Thus, a dedicated APFD source assembly has been constructed and demonstrated to allow for robust APFD operation. This device also enabled observation of the emitter during operation and allowed for resistive emitter heating, thereby speeding up the desorption of the analytes and expanding the range of analytes accessible to APFD. While initial work was done using a Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometer, the new APFD source offered the flexibility to also be used on a trapped ion mobility-quadrupole-time-of-flight (TIMS-Q-TOF) instrument, and thus, it would be possible to be mounted to any Bruker mass spectrometer featuring an atmospheric pressure (AP) interface. Operating an APFD source at a TIMS-Q-TOF instrument called for the exploration of the combined use of APFD and TIMS. Here, operation, basic properties, and capabilities of this new atmospheric pressure field desorption-trapped ion mobility-mass spectrometry (APFD-TIMS-MS) coupling are described. APFD-TIMS-MS is employed for the separation of individual components of oligomers and for the accurate determination of their collision cross section (CCS). This work describes the application of APFD-TIMS-MS on poly(ethylene glycol) forming [M + Na]+ ions by cationization and on an amine-terminated poly(propylene glycol) yielding [M + H]+ ions. Some compounds forming molecular ions, M+•, by field ionization such as [60]fullerene and a mixture of four polycyclic aromatic hydrocarbons (PAHs) are examined. In APFD-TIMS-MS, the limits of detection (LODs) of fluoranthene and benzo[a]pyrene M+• ions are determined as ≈100 pg and <1 pg, respectively. Finally, [60]fullerene is analyzed by negative-ion APFD-TIMS-MS where it yields a molecular anion, M−•.

Graphical abstract
A note on the capacity estimate in metastability for generic configurations
Authors: Avelin Benny , Julin Vesa
Published: April 2024

In this paper we further develop the ideas from Geometric Function Theory initially introduced in Avelin et al. (Commun Math Phys 404:401–437, 2023), to derive capacity estimate in metastability for arbitrary configurations. The novelty of this paper is twofold. First, the graph theoretical connection enables us to exactly compute the pre-factor in the capacity. Second, we complete the method from Avelin et al. (Commun Math Phys 404:401–437, 2023) by providing an upper bound using Geometric Function Theory together with Thompson’s principle, avoiding explicit constructions of test functions.
Meta-analysis of the Microbial Diversity Cultured in Bioreactors Simulating the Gut Microbiome
Authors: Garcia Mendez David Felipe , Egan Siobhon , Wist Julien , Holmes Elaine , Sanabria Janeth
Published: April 2024

Understanding the intricate ecological interactions within the gut microbiome and unravelling its impact on human health is a challenging task. Bioreactors are valuable tools that have contributed to our understanding of gut microbial ecology. However, there is a lack of studies describing and comparing the microbial diversity cultivated in these models. This knowledge is crucial for refining current models to reflect the gastrointestinal microbiome accurately. In this study, we analysed the microbial diversity of 1512 samples from 18 studies available in public repositories that employed cultures performed in batches and various bioreactor models to cultivate faecal microbiota. Community structure comparison between samples using t-distributed stochastic neighbour embedding and the Hellinger distance revealed a high variation between projects. The main driver of these differences was the inter-individual variation between the donor faecal inocula. Moreover, there was no overlap in the structure of the microbial communities between studies using the same bioreactor platform. In addition, α-diversity analysis using Hill numbers showed that highly complex bioreactors did not exhibit higher diversities than simpler designs. However, analyses of five projects in which the samples from the faecal inoculum were also provided revealed an amplicon sequence variants enrichment in bioreactors compared to the inoculum. Finally, a comparative analysis of the taxonomy of the families detected in the projects and the GMRepo database revealed bacterial families exclusively found in the bioreactor models. These findings highlight the potential of bioreactors to enrich low-abundance microorganisms from faecal samples, contributing to uncovering the gut microbial “dark matter”.
Modeling Microbial Community Networks: Methods and Tools for Studying Microbial Interactions
Authors: Srinivasan Shanchana , Jnana Apoorva , Murali Thokur Sreepathy
Published: April 2024

Microbial interactions function as a fundamental unit in complex ecosystems. By characterizing the type of interaction (positive, negative, neutral) occurring in these dynamic systems, one can begin to unravel the role played by the microbial species. Towards this, various methods have been developed to decipher the function of the microbial communities. The current review focuses on the various qualitative and quantitative methods that currently exist to study microbial interactions. Qualitative methods such as co-culturing experiments are visualized using microscopy-based techniques and are combined with data obtained from multi-omics technologies (metagenomics, metabolomics, metatranscriptomics). Quantitative methods include the construction of networks and network inference, computational models, and development of synthetic microbial consortia. These methods provide a valuable clue on various roles played by interacting partners, as well as possible solutions to overcome pathogenic microbes that can cause life-threatening infections in susceptible hosts. Studying the microbial interactions will further our understanding of complex less-studied ecosystems and enable design of effective frameworks for treatment of infectious diseases.
Epiberberine: a potential rumen microbial urease inhibitor to reduce ammonia release screened by targeting UreG
Authors: Zhang Xiaoyin , Xiong Zhanbo , He Yue , Zheng Nan , Zhao Shengguo , Wang Jiaqi
Published: April 2024

Rumen microbial urease inhibitors have been proposed for regulating nitrogen emission and improving nitrogen utilization efficiency in ruminant livestock industry. However, studies on plant-derived natural inhibitors of rumen microbial urease are limited. Urease accessory protein UreG, plays a crucial role in facilitating urease maturation, is a new target for design of urease inhibitor. The objective of this study was to select the potential effective inhibitor of rumen microbial urease from major protoberberine alkaloids in Rhizoma Coptidis by targeting UreG. Our results showed that berberine chloride and epiberberine exerted superior inhibition potential than other alkaloids based on GTPase activity study of UreG. Berberine chloride inhibition of UreG was mixed type, while inhibition kinetics type of epiberberine was uncompetitive. Furthermore, epiberberine was found to be more effective than berberine chloride in inhibiting the combination of nickel towards UreG and inducing changes in the second structure of UreG. Molecular modeling provided the rational structural basis for the higher inhibition potential of epiberberine, amino acid residues in G1 motif and G3 motif of UreG formed interactions with D ring of berberine chloride, while interacted with A ring and D ring of epiberberine. We further demonstrated the efficacy of epiberberine in the ruminal microbial fermentation with low ammonia release and urea degradation. In conclusion, our study clearly indicates that epiberberine is a promising candidate as a safe and effective inhibitor of rumen microbial urease and provides an optimal strategy and suitable feed additive for regulating nitrogen excretion in ruminants in the future.

Key points

• Epiberberine is the most effective inhibitor of rumen urease from Rhizoma Coptidis.

• Urease accessory protein UreG is an effective target for design of urease inhibitor.

• Epiberberine may be used as natural feed additive to reducing NH3 release in ruminants.
Phylogenetic network classes through the lens of expanding covers
Authors: Francis Andrew , Marchei Daniele , Steel Mike
Published: April 2024

It was recently shown that a large class of phylogenetic networks, the ‘labellable’ networks, is in bijection with the set of ‘expanding’ covers of finite sets. In this paper, we show how several prominent classes of phylogenetic networks can be characterised purely in terms of properties of their associated covers. These classes include the tree-based, tree-child, orchard, tree-sibling, and normal networks. In the opposite direction, we give an example of how a restriction on the set of expanding covers can define a new class of networks, which we call ‘spinal’ phylogenetic networks.
Gastrointestinale Stromatumoren
Authors: Wardelmann Eva , Kuntze Anna , Voloshin Artem , Elges Sandra , Trautmann Marcel , Hartmann Wolfgang
Published: April 2024

Gastrointestinale Stromatumoren (GIST) stellen seit über 20 Jahren ein Paradigma für die zielgerichtete Therapie mit Tyrosinkinaseinhibitoren dar. Eine elementare Voraussetzung für eine mögliche neoadjuvante oder adjuvante Behandlung bei lokalisierten GIST bzw. eine additive Therapie bei metastasierten GIST ist die molekulare Typisierung der Tumoren, idealerweise bereits bei Erstdiagnose. Zudem ist auf die Möglichkeit einer hereditären oder syndromalen Prädisposition zu achten, da sich hieraus auch therapeutische Konsequenzen und eine andere Nachsorgestrategie ergeben.
Investigating the effects of Mn content on the morphology and dielectric properties of CdS nanoparticles
Authors: Azab A. A. , Ibrahim R. S. , Seoudi R.
Published: April 2024

CdS nanoparticles doped with Mn were synthesized by chemical precipitation using varying concentrations of Mn at Cd1-xMnxS, where (x) = 0.00, 0.03, 0.05, and 0.07. The samples were examined using scanning electron microscopy (SEM), energy dispersive X-ray techniques (EDX), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, dielectric properties, and AC conductivity measurements. SEM micrograph shows that pure CdS nanomaterial has agglomerates primarily composed of nanoparticles, whereas the sample with a concentration of 0.03 contains smaller particles. In response to the phonon confinement effect, The Raman spectra of CdS nanoparticles exhibited peaks at 303 cm−1and 603 cm−1. In contrast, the Raman spectra of Mn:CdS nanocomposites displayed a prominent fundamental mode at 301 cm−1and a less pronounced overtone mode at 601 cm−1. The dielectric properties and the AC conductivity of CdS have been investigated over a wide frequency range of 0.1 Hz to 10 MHz and at a variety of temperatures ranging from 298 to 423K. The real and imaginary parts of the complex dielectric constant (εʹ, εʹʹ), the electric modulus, and AC conductivity of CdS were found to depend on Mn content at different temperatures.
Multinomial Restricted Unfolding
Authors: Rooij Mark de , Busing Frank
Published: April 2024

For supervised classification we propose to use restricted multidimensional unfolding in a multinomial logistic framework. Where previous research proposed similar models based on squared distances, we propose to use usual (i.e., not squared) Euclidean distances. This change in functional form results in several interpretational advantages of the resulting biplot, a graphical representation of the classification model. First, the conditional probability of any class peaks at the location of the class in the Euclidean space. Second, the interpretation of the biplot is in terms of distances towards the class points, whereas in the squared distance model the interpretation is in terms of the distance towards the decision boundary. Third, the distance between two class points represents an upper bound for the estimated log-odds of choosing one of these classes over the other. For our multinomial restricted unfolding, we develop and test a Majorization Minimization algorithm that monotonically decreases the negative log-likelihood. With two empirical applications we point out the advantages of the distance model and show how to apply multinomial restricted unfolding in practice, including model selection.
On the Existence of Small Strictly Neumaier Graphs
Authors: Abiad Aida , De Boeck Maarten , Zeijlemaker Sjanne
Published: April 2024

A Neumaier graph is a non-complete edge-regular graph containing a regular clique. In this work, we prove several results on the existence of small strictly Neumaier graphs. In particular, we present a theoretical proof of the uniqueness of the smallest strictly Neumaier graph with parameters (16, 9, 4; 2, 4), we establish the existence of a strictly Neumaier graph with parameters (25, 12, 5; 2, 5), and we disprove the existence of strictly Neumaier graphs with parameters (25, 16, 9; 3, 5), (28, 18, 11; 4, 7), (33, 24, 17; 6, 9), (35, 2212; 3, 5), (40, 30, 22; 7, 10) and (55, 34, 18; 3, 5). Our proofs use combinatorial techniques and a novel application of integer programming methods.
En-bloc spondylectomy in the lumbar spine: indications, results and complications in a series of 47 patients affected by primary malignant bone tumors
Authors: Luzzati Alessandro , Conti Stefano , Sperduti Isabella , Scotto Di Uccio Alessandra , Mazzoli Simone , Cannavò Luca , Scotto Gennaro , Zoccali Carmine
Published: April 2024

Introduction

Wide Surgery is the reference treatment for malignant and aggressive benign primary bone tumors in the spine. When located in the lumbar spine, En-Bloc Spondylectomy (EBS) remains a complex challenge. Moreover, surgery is complicated by the presence of the diaphragm in the thoracolumbar junction and the hinderance of the iliac wings at the lumbosacral levels. Therefore, EBS in the lumbar spine frequently requires combined approaches.

The purpose of this study is to describe clinical presentation, tumor characteristics and results of a series of 47 consecutive patients affected by malignant primary bone tumors of the lumbar spine who underwent EBS.

Materials and methods

47 patients were reviewed. Complications were distinguished in early and late whether they occurred before or after 30 days from surgery.

Overall survival (OS), disease-free survival (DFS) and local recurrence-free survival (LRFS) were calculated by the Kaplan–Meier product-limit method from surgery until relapse or death.

Results

27 patients presented to observation after a first intralesional approach in a non-specialized center. Chordoma was the most represented histotype. Vertebrectomies were: 23 one-level, 10 two-level, 12 three-level and 2 four-level. Reconstructions were always carried out with screws and rods. The main postoperative complication was blood loss, while hardware failure was the main long-term complication.

The 5-year LRFS was 75.5%, the 5-year DFS was 54.3%, and 5-year OS was 63.6%.

Conclusions

The surgical margin obtained during the index surgery was statistically associated with Local Recurrence, DFS and OS, underlining the importance of treating patients in reference centers.
Postradiation trismus in head and neck cancer survivors: a qualitative study of effects on life, rehabilitation, used coping strategies and support from the healthcare system
Authors: Aghajanzadeh Susan , Karlsson Therese , Tuomi Lisa , Engström My , Finizia Caterina
Published: April 2024

Purpose

This study aimed to explore the experiences of head and neck cancer (HNC) survivors with postradiation trismus, specifically how oncological treatment affected their lives, rehabilitation, use of coping strategies, and healthcare experiences. Methods: A qualitative descriptive approach was used and semi-structured interviews of 10 HNC survivors with postradiation trismus were conducted 6–30 months after completing oncological treatment. The interviews were transcribed verbatim and analyzed by qualitative content analysis.

Results

The analysis of interviews yielded four main categories: Bodily symptoms, Effects on life, Support from the healthcare system, and Strategies to handle life and symptoms. Participants reported ongoing problems with xerostomia, dysgeusia, eating, and limited physical fitness. Pain related to trismus was not a major issue in this cohort. Participants expressed limitations in their social lives due to their eating difficulties, yet a sense of thankfulness for life and overall satisfaction with the healthcare they received. Psychological and practical coping strategies developed by the participants were also revealed.

Conclusion

The results highlight areas of unmet need among HNC survivors that healthcare providers can target by establishing multi-professional teams dedicated to individualizing post-cancer rehabilitation care.
The extent of androgen receptor and HER2 expression allows for targeted therapy in most cases of salivary duct carcinoma: analysis of clinical and histopathological data in a tertiary care center
Authors: Mayer Marcel , Wolber Philipp , Prinz Johanna , Jansen Louis , Esser Julia , Shabli Sami , Quaas Alexander , Klußmann Jens Peter , Sharma Shachi Jenny , Nachtsheim Lisa , Arolt Christoph
Published: April 2024

Purpose

The incidence of salivary duct carcinoma (SDC) seems to be underestimated due to inaccurate classification. Further, the frequency of SDC patients with targeted therapy options according to current guidelines is unclear. Therefore, this study aimed at (a) describing the proportion of SDC among salivary gland carcinoma (SGC) before and after reclassification of cases initially classified as adenocarcinoma, not otherwise specified (ANOS); and (b) quantifying the frequency of SDC patients with targeted therapy options.

Methods

All patients with SDC or ANOS treated in a tertiary care center between 1996 and 2023 were identified. Histopathological diagnosis was verified for patients primarily diagnosed with SDC and reviewed for patients initially diagnosed with ANOS. Clinical data for SDC patients were retrieved from clinical charts. Immunohistochemical (IHC) androgen receptor (AR) and HER2 staining was performed.

Results

Among 46 SDC, 34 were primarily diagnosed as SDC and 12 had initially been classified as ANOS. The proportion of SDC among SGC was 12.1% and was rising when comparing the time periods 2000–2015 (7.1–11.5%) versus 2016–2023 (15.4–18.1%). Nuclear AR staining in > 70% of tumor cells was found in 56.8% and HER2 positivity (IHC 3 +) in 36.4% of cases. 70.5% of patients showed AR staining in > 70% of tumor cells and/or HER2 positivity and therefore at least one molecular target. 5-year overall and disease-free survival (DFS) were 62.8% and 41.0%. Multivariate Cox regression revealed positive resection margins (HR = 4.0, p = 0.03) as independent negative predictor for DFS.

Conclusions

The results suggest a rising SDC incidence and show that the extent of the AR and HER2 expression allows for targeted therapy in most SDC cases.
Metasomatic ijolite, glimmerite, silicocarbonatite, and antiskarn formation: carbonatite and silicate phase equilibria in the system Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O–O2–CO2
Authors: Anenburg Michael , Walters Jesse B.
Published: April 2024

Silicocarbonatites are carbonatite rocks containing > 20% silicate minerals. Their formation is not well understood due to low silica solubility in carbonatite melts and negligible amounts of silicate minerals on carbonatite melt cotectics at upper crustal conditions. We explore whether silicocarbonatites can be thought of as antiskarns: rocks formed by leaching of SiO2from siliceous wall rocks by carbonatite melts, and its deposition as solid silicate minerals by reaction with chemical components already present in the carbonatite melt. Solid state thermodynamic modelling at 1–5 kbar and 500–800 °C predicts that calcite–dolomite–magnetite assemblages will transform to dolomite-free silicocarbonatites with an increase in silica contents. In sodic systems, the formation of aegirine and alkali amphiboles suppresses silica activity despite elevated silica contents. Therefore, dolomite remains stable, but Fe3+is consumed, firstly from magnetite breakdown, and secondly by coupled Fe oxidation and reduction of CO2to CO, CH4, and graphite, particularly at higher pressures. Despite a net increase in Fe3+/Fe2+, the system evolves to increasingly lower oxygen fugacity. In aluminous systems, nepheline indicates high temperatures whereas alkali feldspars form at lower temperatures. Modelling of potassic systems demonstrates stability of mostly phlogopite-rich biotites, leading to Fe2+increase in all other carbonate and silicate phases. We find that perthites are expected in high pressures whereas two feldspars are more likely in lower pressures.

Aspects of the clinopyroxene natural compositional trend (diopside to hedenbergite to aegirine) of carbonatite systems can be explained by silica contamination. Ferrous clinopyroxenes typically require low alumina and are predicted in potassic or low temperature sodic systems, primarily at mid to high pressures. Silica contamination permits the formation of silicocarbonatite-like assemblages in a way that is not limited by SiO2solubility in carbonatite melts. Glimmerites and clinopyroxene-rich rocks (such as the ijolite series) that often occur around carbonatite rocks at the contact with silica-oversaturated wall rocks can be explained as the extreme end of silica contamination of carbonatite melts. Therefore, these clinopyroxenites and glimmerites can form solely via metasomatic processes without the presence of a silicate melt.
Prediction model for anabolic androgenic steroid positivity in forensic autopsy cases – a new tool to the autopsy room
Authors: Vauhkonen Paula , Oura Petteri , Kriikku Pirkko , Lindroos Katarina , Mäyränpää Mikko Ilari
Published: April 2024

Non-prescription use of anabolic androgenic steroids (AAS) is associated with an increased risk of premature death. However, these substances are seldom screened in connection with forensic cause-of-death investigation, unless the forensic pathologist specifically suspects use, often based on a positive AAS use history. Since AAS use is often concealed from others, this practice may lead to mistargeting of these analyses and significant underestimation of the true number of AAS positive cases undergoing forensic autopsy. Thus, more accurate diagnostic tools are needed to identify these cases. The main objective of this study was to determine, whether a multivariable model could predict AAS urine assay positivity in forensic autopsies. We analyzed retrospectively the autopsy reports of all cases that had been screened for AAS during forensic cause-of-death investigation between 2016–2019 at the Finnish Institute for Health and Welfare forensic units (n = 46). Binary logistic regression with penalized maximum likelihood estimation was used to generate a nine-variable model combining circumferential and macroscopic autopsy-derived variables. The multivariable model predicted AAS assay positivity significantly better than a “conventional” model with anamnestic information about AAS use only (area under the receiver operating characteristic curve [AUC] = 0.968 vs. 0.802, p = 0.005). Temporal validation was conducted in an independent sample of AAS screened cases between 2020–2022 (n = 31), where the superiority of the multivariable model was replicated (AUC = 0.856 vs. 0.644, p = 0.004). Based on the model, a calculator predicting AAS assay positivity is released as a decision-aiding tool for forensic pathologists working in the autopsy room.
Giardia telomeres and telomerase
Authors: Lagunas-Rangel Francisco Alejandro
Published: April 2024

Giardia duodenalis, the protozoan responsible for giardiasis, is a significant contributor to millions of diarrheal diseases worldwide. Despite the availability of treatments for this parasitic infection, therapeutic failures are alarmingly frequent. Thus, there is a clear need to identify new therapeutic targets. Giardia telomeres were previously identified, but our understanding of these structures and the critical role played by Giardia telomerase in maintaining genomic stability and its influence on cellular processes remains limited. In this regard, it is known that all Giardia chromosomes are capped by small telomeres, organized and protected by specific proteins that regulate their functions. To counteract natural telomere shortening and maintain high proliferation, Giardia exhibits constant telomerase activity and employs additional mechanisms, such as the formation of G-quadruplex structures and the involvement of transposable elements linked to telomeric repeats. Thus, this study aims to address the existing knowledge gap by compiling the available information (until 2023) about Giardia telomeres and telomerase, focusing on highlighting the distinctive features within this parasite. Furthermore, the potential feasibility of targeting Giardia telomeres and/or telomerase as an innovative therapeutic strategy is discussed.
The structure of the local time of Markov processes indexed by Lévy trees
Authors: Riera Armand , Rosales-Ortiz Alejandro
Published: April 2024

We construct an additive functional playing the role of the local time—at a fixed point x—for Markov processes indexed by Lévy trees. We start by proving that Markov processes indexed by Lévy trees satisfy a special Markov property which can be thought as a spatial version of the classical Markov property. Then, we construct our additive functional by an approximation procedure and we characterize the support of its Lebesgue-Stieltjes measure. We also give an equivalent construction in terms of a special family of exit local times. Finally, combining these results, we show that the points at which the Markov process takes the value x encode a new Lévy tree and we construct explicitly its height process. In particular, we recover a recent result of Le Gall concerning the subordinate tree of the Brownian tree where the subordination function is given by the past maximum process of Brownian motion indexed by the Brownian tree.
A Ray–Knight theorem for $$\nabla \phi $$ interface models and scaling limits
Authors: Deuschel Jean-Dominique , Rodriguez Pierre-François
Published: April 2024

We introduce a natural measure on bi-infinite random walk trajectories evolving in a time-dependent environment driven by the Langevin dynamics associated to a gradient Gibbs measure with convex potential. We derive an identity relating the occupation times of the Poissonian cloud induced by this measure to the square of the corresponding gradient field, which—generically—isnotGaussian. In the quadratic case, we recover a well-known generalization of the second Ray–Knight theorem. We further determine the scaling limits of the various objects involved in dimension 3, which are seen to exhibit homogenization. In particular, we prove that the renormalized square of the gradient field converges under appropriate rescaling to the Wick-ordered square of a Gaussian free field on$$\mathbb R^3$$R3with suitable diffusion matrix, thus extending a celebrated result of Naddaf and Spencer regarding the scaling limit of the field itself.
Investigation and comparison of permanent magnet rotors produced by different additive manufacturing methods
Authors: Wu Tong , Schwarzer David , Neuwald Tobias , Wüst Paul , Maczionsek Daniel , Seibicke Frank , Rauch Hartmut , Schäfer Uwe
Published: April 2024

The advancements in technology have led to a growing interest in additive manufacturing owing to its numerous benefits such as increased degree of freedom, high flexibility, and material conservation. It has gained particular attention in the production of electrical machines and their active components such as windings, electrical insulation, magnetic core packs, and permanent magnets. This paper investigates the use of two methods, namely fused deposition modeling and cold spray, in the production of hard magnetic components for rotors with surface-mounted magnets. A comparative study was conducted through a combination of finite element simulations and experimental tests.
Impact of age on the transmission of SARS-CoV-2 in healthcare workers
Authors: Corral-Gudino Luis , Del-Amo-Merino María Piedad , Abadía-Otero Jésica , Merino-Velasco Irene , Lorenzo-Fernández Yolanda , García-Cruces-Méndez Jesús , Eiros-Bouza José María , Domínguez-Gil González Marta
Published: April 2024

Background

The incidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV‑2) infection was highest among older adults early in the COVID-19 pandemic; however, this pattern was later reversed with young adults showing the highest incidence. The aim of this study was to identify risk factors in healthcare workers (HCWs) associated with this evolution.

Methods

We conducted a survey nested within a prospective cohort study of 680 HCWs from a tertiary referral public hospital who received 2 doses of SARS-CoV‑2 vaccine in January and February 2021 (VACCICO-VAO cohort). In October 2022 all participants were invited to participate in a survey. Risk factors were tested for association with COVID-19 ever, the number of COVID-19 episodes, and the time to the first episode.

Results

Among 350 respondents (51% response rate, 90% female, mean age 48.1 years), 323 COVID-19 episodes were diagnosed during the study period. Multivariable analysis revealed that age < 35 years vs. > 50 years (odds ratio, OR 2.12, 95% confidence interval, CI 1.27–3.51; P = 0.004) and not maintaining social distance at social events (OR: 1.82, 95% CI: 1.16–3.19; P = 0.011) were associated with a higher risk of COVID-19. Age < 35 years (hazard ratio, HR 1.70, 95% CI 1.14–2.54; P = 0.010), and not maintaining social distance (HR 1.34, 95% CI 1.05–1.72; P = 0.020) were also associated with the time to the first episode.

Conclusions

The youngest HCWs had the highest incidence rate of COVID-19, which was not explained by occupational risk factors or health conditions. The increase in nonoccupational exposure since the end of the lockdowns in summer 2020 could by a key factor.

Graphic abstract
Primary care usage at the end of life: a retrospective cohort study of cancer patients using linked primary and hospital care data
Authors: Grant M. , McCarthy D. , Kearney C. , Collins A. , Sundararajan V. , Rhee J. , Philip J. , Emery J.
Published: April 2024

Purpose

Health service use is most intensive in the final year of a person’s life, with 80% of this expenditure occurring in hospital. Close involvement of primary care services has been promoted to enhance quality end-of-life care that is appropriate to the needs of patients. However, the relationship between primary care involvement and patients’ use of hospital care is not well described. This study aims to examine primary care use in the last year of life for cancer patients and its relationship to hospital usage.

Methods

Retrospective cohort study in Victoria, Australia, using linked routine care data from primary care, hospital and death certificates. Patients were included who died related to cancer between 2008 and 2017.

Results

A total of 758 patients were included, of whom 88% (n = 667) visited primary care during the last 6 months (median 9.1 consultations). In the last month of life, 45% of patients were prescribed opioids, and 3% had imaging requested. Patients who received home visits (13%) or anticipatory medications (15%) had less than half the median bed days in the last 3 months (4 vs 9 days, p < 0.001, 5 vs 10 days, p = 0.001) and 1 month of life (0 vs 2 days, p = 0.002, 0 vs 3 days, p < 0.001), and reduced emergency department presentations (32% vs 46%, p = 0.006, 31% vs 47% p < 0.001) in the final month.

Conclusion

This study identifies two important primary care processes—home visits and anticipatory medication—associated with reduced hospital usage and intervention at the end of life.
Analysis of the Internal Structure of Brenna Sandstone Samples with Respect to the Differences in Measured Quasi-elastic Moduli
Authors: Janeček Ivan , Mishra Deepak Amban , Vishnu Chitralekha Satheesan , Souček Kamil , Hlaváček Petr , Klichová Dagmar , Martinec Petr
Published: April 2024

The Young’s modulus and Poisson’s ratio determined for the rocks under uniaxial or triaxial loading conditions represent necessary input parameters for solving many geotechnical tasks. However, these effective stiffness moduli, particularly the Poisson’s ratios, measured on different samples sometimes substantially differ, even for visually compact and macroscopically homogeneous rock. This has been observed for Brenna sandstone, especially under conditions of conventional triaxial extensions. The aim of this study was, thus, to reveal differences in rock structure that could cause such behavior. Several complementary methods were used to investigate the structure of this sandstone: X-ray computed tomography (CT), visual analysis using optical scanning and stereo-microscopy, and a new method combining water jet erosion with these visualization techniques. Analyses of this structure revealed mechanically more resistant compact thick and adjacent thin weak layers. In rock samples, these layers have different patterns and orientations. To demonstrate the influence of layer orientation on effective stiffness moduli measured under different loading conditions, FEM calculations were performed for idealized structural models. The outcomes of this numerical analysis are in qualitative agreement with the results of the loading experiments and the layered structure revealed in the samples. The ability of the proposed method using water erosion to analyze the rock structure in detail was verified. The method offers an interesting alternative to standard visual and X-ray CT techniques. The numerical calculations indicate the importance of latent layered defects in sedimentary rocks for fine measurements of stiffness moduli (especially the Poisson’s ratios) used as inputs for geotechnical applications.
On the notion of the parabolic and the cuspidal support of smooth-automorphic forms and smooth-automorphic representations
Authors: Grobner Harald , Žunar Sonja
Published: April 2024

In this paper we describe several new aspects of the foundations of the representation theory of the space of smooth-automorphic forms (i.e., not necessarily $$K_\infty $$

K
∞

-finite automorphic forms) for general connected reductive groups over number fields. Our role model for this space of smooth-automorphic forms is a “smooth version” of the space of automorphic forms, whose internal structure was the topic of Franke’s famous paper (Ann Sci de l’ENS 2:181–279, 1998). We prove that the important decomposition along the parabolic support, and the even finer—and structurally more important—decomposition along the cuspidal support of automorphic forms transfer in a topologized version to the larger setting of smooth-automorphic forms. In this way, we establish smooth-automorphic versions of the main results of Franke and Schwermer (Math Ann 311:765–790, 1998) and of Mœglin and Waldspurger (Spectral Decomposition and Eisenstein Series, Cambridge University Press, 1995), III.2.6.
Identification of a novel HIV-1 third-generation circulating recombinant form (CRF126_0755) in Guangdong, China
Authors: Lan Yun , Xin Ruolei , He Ruiying , Li Feng , Ling Xuemei , Li Linghua , Hu Fengyu
Published: April 2024

The genetic recombination patterns and genetic distribution of HIV-1 are valuable for elucidating the epidemic and genetic diversity of HIV. Numerous HIV-1 circulating recombinant forms (CRFs) have recently emerged and disseminated rapidly. In China, at least 32 CRFs have been reported to account for more than 80% of all HIV infections. However, CRFs derived from the CRF07_BC and CRF55_01B lineages have never been recorded. Here, a novel third-generation CRF involving HIV-1 was identified in four HIV-1-infected patients in Guangdong, China, who had no epidemiological association with each other. Phylogenetic and recombinant analyses confirmed that these strains shared highly similar recombination patterns, with the CRF07_BC backbone substituted by a CRF55_01B segment; therefore, these strains were classified as CRF126_0755. This is the first study of a CRF derived from CRF07_BC and CRF55_01B. Bayesian phylogenetic inference suggested that CRF126_0755 originated in approximately 2005-2007. The present findings reveal that the genotype composition of HIV-1 has become more complex than that of other viruses and highlight the urgent need for continuous molecular screening and epidemic surveillance within HIV-1-infected populations to advance our understanding of viral transmission mechanisms.
Development and validation of a predictive model for poor prognosis of communication disorders in children with cerebral palsy after cervical perivascular sympathectomy
Authors: Wu Junjie , Bai Chao , Yan Baofeng , Mutalifu Nurehemaiti , Guan Qi , Li Jianglong , Luan Xinping
Published: April 2024

Cervical perivascular sympathectomy (CPVS) can improve communication disorders in children with cerebral palsy (CP); however, there are no research reports on the factors affecting surgical efficacy. This study aimed to establish a nomogram for poor prognosis after CPVS. We collected data from 313 CP patients who underwent CPVS at the Neurosurgery Cerebral Palsy Center of the Second Affiliated Hospital of Xinjiang Medical University from January 2019 to January 2023. Among them, 70% (n = 216) formed the training cohort and 30% (n = 97) the validation cohort. The general data and laboratory examination data of both groups were analyzed. In training cohort, 82 (37.96%) showed improved postoperative communication function. Logistic analysis identified motor function, serum alkaline phosphatase, serum albumin, and prothrombin activity as the prognostic factors. Using these four factors, a prediction model was constructed with an area under the curve (AUC) of 0.807 (95% confidence interval [CI], 0.743–0.870), indicating its ability to predict adverse outcomes after CPVS. The validation cohort results showed an AUC of 0.76 (95% CI, 0.650–0.869). The consistency curve and Hosmer–Lemeshow test (χ2 = 10.988 and p = 0.202, respectively) demonstrated good consistency between the model-predicted incidence and the actual incidence of poor prognosis. Motor function, serum alkaline phosphatase, serum albumin, and prothrombin activity are independent risk factors associated with the prognosis of communication disorders after CPVS. The combined prediction model has a good clinical prediction effect and has promising potential to be used for early prediction of prognosis of CPVS.
Cold Hardiness in ‘Alphonse Lavallee’ (Vitis vinifera L. cv) Grape Dormant Buds and Phloem Tissue: Seasonal Insights and Some Treatment Impacts
Authors: Kose Bulent , Uray Yahya , Bayram Kevser , Yilmaz Turhan , Kaya Ozkan
Published: April 2024

Grapes are highly susceptible to cold damage during critical developmental stages, impacting viticulture. Understanding the intricate dynamics of cold hardiness in grape dormant buds and phloem tissue is crucial for developing effective mitigation strategies. In this study, we investigated the LT50 values, representing the temperature at which 50% of buds are damaged, under different treatments and sampling times. In our research, we evaluated the effects of four treatments—potassium oxide (K2O), calcium chloride (CaCl2), seaweed (SW), and a control—on the cold hardiness of grapevine buds and phloem tissue. Primary bud LT50 values varied across seasons, with January at −22.46 °C, February at −22.35 °C, and March at −20.45 °C. K2O treatment showed a trend toward improvement, although the difference from the control (−21.99 °C) was not statistically significant. Regarding LT50 values, CaCl2 and SW applications did not significantly differ from the control. Tertiary buds, however, exhibited a substantial enhancement in cold hardiness with K2O application, displaying significantly lower LT50 values compared to the control (−23.55 °C). Phloem tissue LT50 values did not significantly differ among treatments, showing less variability. Bud water content significantly increased with K2O application in all sampling periods (January: 35.41% vs. 35.61%; February: 34.03% vs. 39.16%; March: 42.40% vs. 37.82%), while shoot water content remained stable. In conclusion, K2O emerges as a key influencer, particularly in enhancing the cold hardiness of tertiary buds. These insights contribute to the knowledge base for targeted frost mitigation strategies in viticulture.