bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ossification of the acetabular rim: a highly prevalent finding in asymptomatic non-osteoarthritic hips of all ages
Authors: Valente Catarina , Haefliger Laura , Favre Julien , Omoumi Patrick 
Published: March 2021

Abstract
Objective
To estimate the prevalence of acetabular rim ossifications in the adult population with asymptomatic, morphologically normal hips at CT and to determine whether the presence of these ossifications is associated with patient- or hip-related parameters.

Methods
We prospectively included all patients undergoing thoracoabdominal CT over a 3-month period. After exclusion of patients with a clinical history of hip pathology and/or with signs of osteoarthritis on CT, we included a total of 150 hips from 75 patients. We analyzed the presence and the size of ossifications around the acetabular rim. The relationships between the size of acetabular rim ossifications and patient-related (sex, age, BMI) or hip-related parameters (joint space width, and cam- and pincer-type femoroacetabular impingement morphology) were tested using multiple regression analysis.

Results
The prevalence of acetabular rim ossifications in this population of asymptomatic, non-osteoarthritic hips was 96% (95% CI = [80.1; 100.0]). The presence of ossifications and their size were correlated between the right and left hips (Spearman coefficient = 0.64 (95% CI = [0.46;0.79]), p < 0.05)). The size of acetabular rim ossifications was significantly associated with age (p < 0.0001) but not with BMI (p = 0.35), gender (p = 0.05), joint space width (p ≥ 0.53 for all locations), or any of the qualitative or quantitative parameters associated with femoroacetabular morphology (p ≥ 0.34).

Conclusion
Acetabular rim ossifications are highly prevalent in asymptomatic, non-osteoarthritic adult hips at all ages. Their size is not correlated with any patient- or hip-related parameters except for age. These findings suggest that ossifications at the acetabular rim, when present in isolation, should not be considered a sign of osteoarthritis or femoroacetabular impingement morphology.

Key Points
• Acetabular rim ossifications are extremely common in asymptomatic, non-osteoarthritic adult hips.
• Acetabular rim ossifications are present independently from other signs of osteoarthritis in adult hips at all ages and should not be interpreted as a pathological finding.
• The diagnosis of osteoarthritis or femoroacetabular impingement morphology should not be made based on the sole presence of ossifications at the acetabular rim.
Threshold-dependent iodine imaging and spectral separation in a whole-body photon-counting CT system
Authors: Sawall S. , Klein L. , Wehrse E. , Rotkopf L. T. , Amato C. , Maier J. , Schlemmer H.-P. , Ziener C. H. , Heinze S. , Kachelrieß M. 
Published: March 2021

Abstract
Objective
To evaluate the dual-energy (DE) performance and spectral separation with respect to iodine imaging in a photon-counting CT (PCCT) and compare it to dual-source CT (DSCT) DE imaging.

Methods
A semi-anthropomorphic phantom extendable with fat rings equipped with iodine vials is measured in an experimental PCCT. The system comprises a PC detector with two energy bins (20 keV, T) and (T, eU) with threshold T and tube voltage U. Measurements using the PCCT are performed at all available tube voltages (80 to 140 kV) and threshold settings (50–90 keV). Further measurements are performed using a conventional energy-integrating DSCT. Spectral separation is quantified as the relative contrast media ratio R between the energy bins and low/high images. Image noise and dose-normalized contrast-to-noise ratio (CNRD) are evaluated in resulting iodine images. All results are validated in a post-mortem angiography study.

Results
R of the PC detector varies between 1.2 and 2.6 and increases with higher thresholds and higher tube voltage. Reference R of the EI DSCT is found as 2.20 on average overall phantoms. Maximum CNRD in iodine images is found for T = 60/65/70/70 keV for 80/100/120/140 kV. The highest CNRD of the PCCT is obtained using 140 kV and is decreasing with decreasing tube voltage. All results could be confirmed in the post-mortem angiography study.

Conclusion
Intrinsically acquired DE data are able to provide iodine images similar to conventional DSCT. However, PCCT thresholds should be chosen with respect to tube voltage to maximize image quality in retrospectively derived image sets.

Key Points
• Photon-counting CT allows for the computation of iodine images with similar quality compared to conventional dual-source dual-energy CT.
• Thresholds should be chosen as a function of the tube voltage to maximize iodine contrast-to-noise ratio in derived image sets.
• Image quality of retrospectively computed image sets can be maximized using optimized threshold settings.
A novel knockout mouse for the small EDRK-rich factor 2 (Serf2) showing developmental and other deficits
Authors: Cleverley Karen , Lee Weaverly Colleen , Mumford Paige , Collins Toby , Rickman Matthew , Cunningham Thomas J. , Cleak James , Mianne Joffrey , Szoke-Kovacs Zsombor , Stewart Michelle , Teboul Lydia , Maduro Cheryl , Wells Sara , Wiseman Frances K. , Fisher Elizabeth M. C. 
Published: March 2021

AbstractThe small EDRK-rich factor 2 (SERF2) is a highly conserved protein that modifies amyloid fibre assembly in vitro and promotes protein misfolding. However, the role of SERF2 in regulating age-related proteotoxicity remains largely unexplored due to a lack of in vivo models. Here, we report the generation of Serf2 knockout mice using an ES cell targeting approach, with Serf2 knockout alleles being bred onto different defined genetic backgrounds. We highlight phenotyping data from heterozygous Serf2+/− mice, including unexpected male-specific phenotypes in startle response and pre-pulse inhibition. We report embryonic lethality in Serf2−/− null animals when bred onto a C57BL/6 N background. However, homozygous null animals were viable on a mixed genetic background and, remarkably, developed without obvious abnormalities. The Serf2 knockout mice provide a powerful tool to further investigate the role of SERF2 protein in previously unexplored pathophysiological pathways in the context of a whole organism.
Independent Domination Subdivision in Graphs
Authors: Babikir Ammar , Dettlaff Magda , Henning Michael A. , Lemańska Magdalena 
Published: March 2021

AbstractA set S of vertices in a graph G is a dominating set if every vertex not in S is ad jacent to a vertex in S. If, in addition, S is an independent set, then S is an independent dominating set. The independent domination number i(G) of G is the minimum cardinality of an independent dominating set in G. The independent domination subdivision number $$ \hbox {sd}_{\mathrm{i}}(G)$$

sd
i

(
G
)

is the minimum number of edges that must be subdivided (each edge in G can be subdivided at most once) in order to increase the independent domination number. We show that for every connected graph G on at least three vertices, the parameter $$ \hbox {sd}_{\mathrm{i}}(G)$$

sd
i

(
G
)

is well defined and differs significantly from the well-studied domination subdivision number $$\mathrm{sd_\gamma }(G)$$

sd
γ

(
G
)

. For example, if G is a block graph, then $$\mathrm{sd_\gamma }(G) \le 3$$

sd
γ

(
G
)

≤
3

, while $$ \hbox {sd}_{\mathrm{i}}(G)$$

sd
i

(
G
)

can be arbitrary large. Further we show that there exist connected graph G with arbitrarily large maximum degree $$\Delta (G)$$

Δ
(
G
)

such that $$ \hbox {sd}_{\mathrm{i}}(G) \ge 3 \Delta (G) - 2$$

sd
i

(
G
)

≥
3
Δ

(
G
)

-
2

, in contrast to the known result that $$\mathrm{sd_\gamma }(G) \le 2 \Delta (G) - 1$$

sd
γ

(
G
)

≤
2
Δ

(
G
)

-
1

always holds. Among other results, we present a simple characterization of trees T with $$ \hbox {sd}_{\mathrm{i}}(T) = 1$$

sd
i

(
T
)

=
1

.
Sympathetic and sensory nerve fiber function in multiple system atrophy and idiopathic Parkinson’s disease
Authors: Krämer Heidrun H. , Rebhorn Cora , Geber Christian , Birklein Frank 
Published: March 2021

Abstract
Objective
To explore small fiber somatosensory and sympathetic function in PD and MSA.

Methods
We recruited 20 PD patients (7 women, median age 65.5 years; IQR 54.75–70.0), 10 MSA patients (4 women; median age 68 years; IQR 66.25–74.0), and 10 healthy subjects (HC; 4 women, median age 68; IQR 59.0–71.0 years). Autonomic testing included forehead cooling, intradermal microdialysis of norepinephrine (NE; 10–5; 10–6; 10–7; and 10–8), and orthostatic hypotension (OH); somatosensory testing included quantitative sensory testing (QST) according to the protocol of the German Research Network on Neuropathic Pain (DFNS).

Results
OH occurred more frequently in PD (p = 0.018) and MSA (p = 0.002) compared to HC. Vasoconstriction responses were stronger in PD compared to MSA during forehead cooling (p = 0.044) and microdialysis of physiologically concentrated NE solutions (10–7; 10–8; p = 0.017). PD and MSA had impaired cold (PD: p < 0.01; MSA: p < 0.05) and warm detection thresholds (PD and MSA, both p < 0.05). The mechanical detection threshold was higher in PD (p < 0.01). Conversely, mechanical pain thresholds were decreased in PD and MSA (both p < 0.001), indicating mechanical hyperalgesia.

Conclusion
In contrast to MSA, we found evidence of peripheral adrenoreceptor hypersensitivity in PD, probably caused by peripheral sympathetic denervation. Sensory testing revealed peripheral neuropathy and central pain sensitization in PD and MSA. Jointly, our data demonstrate autonomic and somatosensory dysfunction in PD and MSA.
An exploratory study to investigate the association between age, physical activity, femoral trochlear cartilage thickness and biomarkers of tissue metabolism in adult males
Authors: Roberts Harry M. , Griffith-McGeever Claire L. , Owen Julian A. , Angell Lewis , Moore Jonathan P. , Thom Jeanette M. 
Published: March 2021

Abstract
Purpose
To investigate the association between age, physical activity, femoral trochlear cartilage thickness and biomarkers of tissue metabolism in a cross-sectional sample of adult males. This study utilizes several emerging biomarkers that have been associated with early joint degenerative changes; serum COMP (cartilage oligomeric matrix protein), HA (hyaluronan) and lubricin.

Methods
Eighty-one males (age: mean (range): 43(18–70) years; body mass index: 25.2 (21.0–30.6) kg/m2) volunteered. Resting serum COMP, HA and lubricin concentrations were determined via commercially available enzyme-linked immunosorbent assay (ELISA) and femoral trochlear cartilage thickness via supra-patellar ultrasound imaging. Physical activity levels were assessed using questionnaires. Statistical analyses were performed using correlation and regression analyses.

Results
Age was correlated with lateral trochlear cartilage thickness (r = − 0.372; p < 0.01) and serum COMP (r = 0.342; p < 0.01). 7-day physical activity was correlated with serum COMP (r = 0.357, p < 0.01), and 12-month physical activity with both lateral trochlear cartilage thickness (r = 0.340, p = 0.01) and serum HA (r = 0.296, p < 0.05). Regression analyses revealed that age significantly accounted for the variability in lateral cartilage thickness and serum COMP, following the adjustment for potential cofounders. However, the association between age and lateral trochlear cartilage thickness was not moderated by physical activity levels (all p > 0.05).

Conclusion
This study indicates that older age may be associated with thinner lateral trochlear cartilage and higher cartilage turnover. Being physically active may also be positive for lateral trochlear cartilage thickness. However, overall, both age and physical activity level only account for a small amount of the variability in cartilage thickness and serum biomarkers.
Decreased exercise capacity in young athletes using self-adapted mouthguards
Authors: Lässing Johannes , Falz Roberto , Schulze Antina , Pökel Christoph , Vondran Maximilian , Schröter Thomas , Borger Michael A. , Busse Martin 
Published: March 2021

AbstractPurposeThere is evidence of both the preventive effects and poor acceptance of mouthguards. There are various effects on performance depending on the type of mouthguard model. Hemodynamic responses to wearing a mouthguard have not been described. The aim of this study was to investigate the effects of self-adapted mouthguards with breathing channels (SAMGvent).MethodsIn this randomized crossover study, 17 healthy, active subjects (age 25.12 ± 2.19 years) underwent body plethysmography and performed two incremental exertion tests wearing a (SAMGvent) and not wearing (CON) a mouthguard. Blood lactate, spirometrics, and thoracic impedance were measured during these maximum exercise tests.ResultsThe mean values using a SAMGventrevealed significantly greater airway resistance compared to CON (0.53 ± 0.16 kPa·L−1vs. 0.35 ± 0.10 kPa·L−1, respectively;p = < 0.01). At maximum load, ventilation with SAMGventwas less than CON (118.4 ± 28.17 L min−1vs. 128.2 ± 32.16 L min−1, respectively;p = < 0.01). At submaximal loads, blood lactate responses with SAMGventwere higher than CON (8.68 ± 2.20 mmol·L−1vs. 7.89 ± 1.65 mmol·L−1, respectively;p < 0.01). Maximum performance with a SAMGventwas 265.9 ± 59.9 W, and without a mouthguard was 272.9 ± 60.8 W (p < 0.01). Maximum stroke volume was higher using a SAMGventthan without using a mouthguard (138.4 ± 29.9 mL vs. 130.2 ± 21.2 mL, respectively;p < 0.01).ConclusionUse of a self-adapted mouthguard led to increased metabolic effort and a significant reduction in ventilation parameters. Unchanged oxygen uptake may be the result of cardiopulmonary compensation and increased breathing efforts, which slightly affects performance. These results and the obvious preventive effects of mouthguards support their use in sports.
Brachial and central blood pressure and arterial stiffness in adult elite athletes
Authors: Tomschi Fabian , Ottmann Hannah , Bloch Wilhelm , Grau Marijke , Predel Hans-Georg 
Published: March 2021

AbstractPurposeMeasures of arterial stiffness (AS) and central blood pressure (BP) are indicators for cardiovascular health and possess a high prognostic value in the prediction of cardiovascular events. The effects of physical training are widely unexplored in the context of competitive, high-performance sports. Therefore, we aimed to present possible reference values of brachial and central BP and of AS of adult elite athletes compared to a control group.MethodsA total of 189 subjects participated in this cross-sectional study. Of these were 139 adult elite athletes (70 male, 69 female) performing on top-national and international level, and 50 control subjects (26 male, 24 female). Resting brachial and central BP and aortic pulse wave velocity (PWV) were measured and were compared in terms of sex, sport category, and age of the athletes.ResultsResults show no difference between athletes and controls in any parameter. Women exhibit lower brachial and central BP and AS values compared to men. PWV is positively correlated with age. Evaluation of the parameters according to the different sport categories showed that endurance athletes exhibit lower BP and PWV compared to other athletes.ConclusionsThis study presents brachial and central BP and PWV values of athletes, suggesting that high-performance sport does not negatively impact AS. The proposed reference values might support a more detailed evaluation of elite athlete’s cardiovascular and hemodynamic system and a better assignment to possible risk groups.
The bead process for beta ensembles
Authors: Najnudel Joseph , Virág Bálint 
Published: March 2021

AbstractThe bead process introduced by Boutillier is a countable interlacing of the $${\text {Sine}}_2$$

Sine
2

point processes. We construct the bead process for general $${\text {Sine}}_{\beta }$$

Sine
β

processes as an infinite dimensional Markov chain whose transition mechanism is explicitly described. We show that this process is the microscopic scaling limit in the bulk of the Hermite $$\beta $$
β
corner process introduced by Gorin and Shkolnikov, generalizing the process of the minors of the Gaussian Unitary and Orthogonal Ensembles. In order to prove our results, we use bounds on the variance of the point counting of the circular and the Gaussian beta ensembles, proven in a companion paper (Najnudel and Virág in Some estimates on the point counting of the Circular and the Gaussian Beta Ensemble, 2019).
Hardware implementation of radial-basis neural networks with Gaussian activation functions on FPGA
Authors: Shymkovych Volodymyr , Telenyk Sergii , Kravets Petro 
Published: March 2021

AbstractThis article introduces a method for realizing the Gaussian activation function of radial-basis (RBF) neural networks with their hardware implementation on field-programmable gaits area (FPGAs). The results of modeling of the Gaussian function on FPGA chips of different families have been presented. RBF neural networks of various topologies have been synthesized and investigated. The hardware component implemented by this algorithm is an RBF neural network with four neurons of the latent layer and one neuron with a sigmoid activation function on an FPGA using 16-bit numbers with a fixed point, which took 1193 logic matrix gate (LUTs—LookUpTable). Each hidden layer neuron of the RBF network is designed on an FPGA as a separate computing unit. The speed as a total delay of the combination scheme of the block RBF network was 101.579 ns. The implementation of the Gaussian activation functions of the hidden layer of the RBF network occupies 106 LUTs, and the speed of the Gaussian activation functions is 29.33 ns. The absolute error is ± 0.005. The Spartan 3 family of chips for modeling has been used to get these results. Modeling on chips of other series has been also introduced in the article. RBF neural networks of various topologies have been synthesized and investigated. Hardware implementation of RBF neural networks with such speed allows them to be used in real-time control systems for high-speed objects.
Origin of andradite in the Quaternary volcanic Andahua Group, Central Volcanic Zone, Peruvian Andes
Authors: Gałaś Andrzej , Majka Jarosław , Włodek Adam 
Published: March 2021

AbstractEuhedral andradite crystals were found in trachyandesitic (latitic) lavas of the volcanic Andahua Group (AG) in the Central Andes. The AG comprises around 150 volcanic centers, most of wich are monogenetic. The studied andradite is complexly zoned (enriched in Ca and Al in its core and mantle, and in Fe in this compositionally homogenous rim). The core-mantle regions contain inclusions of anhydrite, halite, S- and Cl-bearing silicate glass, quartz, anorthite, wollastonite magnetite and clinopyroxene. The chemical compositions of the garnet and its inclusions suggest their contact metamorphic to pyrometamorphic origin. The observed zoning pattern and changes in the type and abundance of inclusions are indicative of an abrupt change in temperature and subsequent devolatilization of sulfates and halides during the garnet growth. This process is interpreted to have taken place entirely within a captured xenolith of evaporite-bearing wall rock in the host trachyandesitic magma. The devolitilization of sediments, especially sulfur-bearing phases, may have resulted in occasional but voluminous emissions of gases and may be regarded as a potential hazard associated with the AG volcanism.
Critical evaluation of a crystal structure of nitrogenase with bound N2 ligands
Authors: Bergmann Justin , Oksanen Esko , Ryde Ulf 
Published: March 2021

AbstractRecently, a 1.83 Å crystallographic structure of nitrogenase was suggested to show N2-derived ligands at three sites in the catalytic FeMo cluster, replacing the three $$\mu_{2}$$

μ
2

bridging sulfide ligands (two in one subunit and the third in the other subunit) (Kang et al. in Science 368: 1381–1385, 2020). Naturally, such a structure is sensational, having strong bearings on the reaction mechanism of the enzyme. Therefore, it is highly important to ensure that the interpretation of the structure is correct. Here, we use standard crystallographic refinement and quantum refinement to evaluate the structure. We show that the original crystallographic raw data are strongly anisotropic, with a much lower resolution in certain directions than others. This, together with the questionable use of anisotropic B factors, give atoms an elongated shape, which may look like diatomic atoms. In terms of standard electron-density maps and real-space Z scores, a resting-state structure with no dissociated sulfide ligands fits the raw data better than the interpretation suggested by the crystallographers. The anomalous electron density at 7100 eV is weaker for the putative N2 ligands, but not lower than for several of the $${\mu }_{3}$$

μ
3

bridging sulfide ions and not lower than what can be expected from a statistical analysis of the densities. Therefore, we find no convincing evidence for any N2 binding to the FeMo cluster. Instead, a standard resting state without any dissociated ligands seems to be the most likely interpretation of the structure. Likewise, we find no support that the homocitrate ligand should show monodentate binding.
Graphic abstract
Evaluation of the Ventral Hernia Working Group classification for long-term outcome using English Hospital Episode Statistics: a population study
Authors: Hodgkinson J. D. , Worley G. , Warusavitarne J. , Hanna G. B. , Vaizey C. J. , Faiz O. D. 
Published: March 2021

Abstract
Purpose
The Ventral Hernia Working Group (VHWG) classification of ventral/incisional hernia (IH) was developed by expert consensus in 2010. Subsequently, Kanters et al. have demonstrated the validity of a modified version of the system for predicting short-term outcomes. This study aims to evaluate the modified system for predicting hernia recurrence.

Methods
Patients undergoing IH surgery (defined by OPCS codes) in the England Hospital Episode Statistics (HES) database, from 1997 to 2012, were identified. Baseline demographics at index hernia operation and episodes of further hernia surgery (FHS) were recorded. Risk factors for FHS were identified using cox regression and evaluated against the modified-VHWG grade using receiver-operating characteristics (ROC).

Results
The final analysis included 214,082 index IH operations. Of these, 52.6% were female and mean age was 56.59 (SD15.9). An admission for FHS was found in 8.3% cases (17,714 patients).
Multi-variate cox regression revealed contaminated hernia (p < 0.0001), pre-existing IBD (p < 0.0001) and hernia comorbidity (p = 0.05) to be significantly related to long-term FHS. Classifying patients using these factors, according to the modified-VHWG classification, revealed that compared to Grade 1, the hazard ratio (HR) of FHS increased in Grade 2 (HR 1.19; p < 0.0001) and further increased in Grade 3 (HR 1.79; p < 0.0001). ROC analysis revealed the area under the curve to be 0.73 (95% CI 0.73–0.74).

Conclusion
This analysis demonstrates the broad validity of the modified-VHWG classification in discriminating risk for FHS. Inclusion of pre-existing IBD as a factor defining Grade 2 patients would be recommended. This analysis is limited by the absence of certain factors within the HES database, such as BMI.