bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of Conventional Dynamic Myelography for Detection of High-Flow Cerebrospinal Fluid Leaks
Authors: Piechowiak Eike I. , Pospieszny Katarzyna , Haeni Levin , Jesse Christopher M. , Peschi Giovanni , Mosimann Pascal J. , Kaesmacher Johannes , Mordasini Pasquale , Raabe Andreas , Ulrich Christian T. , Beck Jürgen , Gralla Jan , Dobrocky Tomas 
Published: August 2020

Abstract
Background
Spinal imaging is essential to identify and localize cerebrospinal fluid (CSF) leaks in spontaneous intracranial hypotension (SIH) patients when targeted treatment is necessary.

Purpose
Provide an in-depth presentation of the conventional dynamic myelography (CDM) technique for localizing spinal CSF leaks in SIH patients.

Material and Methods
Consecutive SIH patients with a CSF leak confirmed on CDM and postmyelography computed tomography (CT) investigated at our institution between 2013 and 2019 were retrospectively analyzed. Intraoperative reports were reviewed to confirm the accuracy of CDM.

Results
In total, 62 patients (mean age 45 years) were included; 48 with a ventral dural tear, 12 with a meningeal diverticulum, and in 2 patients positive for spinal longitudinal extradural CSF collection the site remained unclear. The leak was identified during the first and the second CDM in 43 and 17 patients, respectively. The use of CDM correctly identified the site of the CSF leak in all but one patient undergoing surgical closure (45/46, 98%). The mean fluoroscopy time was 7.8 min (range 1.8–14.4 min) with a radiation dose for a single examination of 310 mGy (range 28–1237 mGy).

Conclusion
The CDM procedure has a high accuracy for spinal CSF leak localization including dural tears and spinal nerve diverticula. It is the technique with the highest temporal resolution, is robust to breathing artifacts, allows great flexibility regarding patient positioning, compares favorably to other dynamic examinations with respect to the radiation dose and does not require general anesthesia. For CSF venous fistulas, however, other dynamic examinations, such as digital subtraction myelography, seem more appropriate.
Expanding and validating the biomarkers for mitochondrial diseases
Authors: Maresca Alessandra , Del Dotto Valentina , Romagnoli Martina , La Morgia Chiara , Di Vito Lidia , Capristo Mariantonietta , Valentino Maria Lucia , Carelli Valerio ,   the ER-MITO Study Group
Published: August 2020

Abstract
Mitochondrial diseases are highly heterogeneous metabolic disorders caused by genetic alterations in the mitochondrial DNA (mtDNA) or in the nuclear genome. In this study, we investigated a panel of blood biomarkers in a cohort of 123 mitochondrial patients, with prominent neurological and muscular manifestations. These biomarkers included creatine, fibroblast growth factor 21 (FGF21) and growth/differentiation factor 15 (GDF-15), and the novel cell free circulating-mtDNA (ccf-mtDNA). All biomarkers were significantly increased in the patient group. After stratification by the specific phenotypes, ccf-mtDNA was significantly increased in the Mitochondrial Encephalomyopathy Lactic Acidosis Stroke-like episodes syndrome (MELAS) group, and FGF21 and GDF-15 were significantly elevated in patients with MELAS and Myoclonic Epilepsy Ragged Red Fibers syndrome. On the contrary, in our cohort, creatine was not associated to a specific clinical phenotype. Longitudinal assessment in four MELAS patients showed increased levels of ccf-mtDNA in relation to acute events (stroke-like episodes/status epilepticus) or progression of neurodegeneration. Our results confirm the association of FGF21 and GDF-15 with mitochondrial translation defects due to tRNA mutations. Most notably, the novel ccf-mtDNA was strongly associated with MELAS and may be used for monitoring the disease course or to evaluate the efficacy of therapies, especially in the acute phase.

Key messages
• FGF21/GDF15 efficiently identifies mitochondrial diseases due to mutations in tRNA genes.
• The novel ccf-mtDNA is associated with MELAS and increases during acute events.
• Creatine only discriminates severe mitochondrial patients.
• FGF21, GDF-15, and ccf-mtDNA are possibly useful for monitoring therapy efficacy.
Estimation of autocovariance matrices for high dimensional linear processes
Authors: Furmańczyk Konrad 
Published: August 2020

AbstractIn this paper under some mild restrictions upper bounds on the rate of convergence for estimators of $$p\times p$$

p
×
p

autocovariance and precision matrices for high dimensional linear processes are given. We show that these estimators are consistent in the operator norm in the sub-Gaussian case when $$p={\mathcal {O}}\left( n^{\gamma /2}\right) $$

p
=
O

n

γ
/
2

for some $$\gamma >1$$

γ
>
1

, and in the general case when $$ p^{2/\beta }(n^{-1} \log p)^{1/2}\rightarrow 0$$

p

2
/
β

(

n

-
1

log
p
)

1
/
2

→
0

for some $$\beta >2$$

β
>
2

as $$ p=p(n)\rightarrow \infty $$

p
=
p
(
n
)
→
∞

and the sample size $$n\rightarrow \infty $$

n
→
∞

. In particular our results hold for multivariate AR processes. We compare our results with those previously obtained in the literature for independent and dependent data. We also present non-asymptotic bounds for the error probability of these estimators.
Tert-butyldimethylsilyl chitosan synthesis and characterization by analytical ultracentrifugation, for archaeological wood conservation
Authors: Wakefield Jennifer M. K. , Braovac Susan , Kutzke Hartmut , Stockman Robert A. , Harding Stephen E. 
Published: August 2020

AbstractThe Oseberg ship is one of the most important archaeological testimonies of the Vikings. After excavation in 1904, the wooden gravegoods were conserved using alum salts. This resulted in extreme degradation of a number of the objects a hundred years later through acid depolymerisation of cellulose and lignin. The fragile condition of the artefacts requires a reconsolidation which has to be done avoiding water as solvent. We synthesized tert-butyldimethylsilyl (TBDMS) chitosan which is soluble in a 50:50 solution of ethyl acetate and toluene. Measurement of its molecular weight, to anticipate its penetration, provided a challenge as the density difference of the polymer and solvent was too small to provide adequate solute redistribution under a centrifugal field, so a two-stage process was implemented (i) determination of the weight-average molar mass of the aqueous soluble activated precursor, chitosan mesylate, Mw,mc using sedimentation equilibrium with the SEDFIT-MSTAR algorithm, and determination of the degree of polymerisation DP; (ii) measurement of the average degree of substitution DSTBDMS of the TBDMS group on each chitosan monosaccharide monomer unit using NMR, to augment the Mw,mc value to give the molar mass of the TBDMS-chitosan. For the preparation, we find Mw = 9.8 kg·mol−1, which is within the acceptable limit for penetration and consolidation of degraded wood. Future work will test this on archaeological wood from different sources.
Differentiating rheumatoid and psoriatic arthritis: a systematic analysis of high-resolution magnetic resonance imaging features—preliminary findings
Authors: Abrar Daniel B. , Schleich Christoph , Brinks Ralph , Goertz Christine , Schneider Matthias , Nebelung Sven , Sewerin Philipp 
Published: August 2020

Abstract
Background
Because of overlapping phenotypical presentations, the diagnostic differentiation of rheumatoid arthritis (RA) and psoriatic arthritis (PsA) remains challenging. Thus, this study aimed to examine the diagnostic value of distinct imaging features obtained by high-resolution 3-T MRI for the diagnostic differentiation.

Materials and methods
Seventeen patients with PsA and 28 patients with RA were imaged at high resolution using 3-T MRI scanners and a dedicated 16-channel hand coil. All images were analyzed according to the outcome measures in rheumatology clinical trials’ (OMERACT) RAMRIS (Rheumatoid Arthritis Magnetic Resonance Imaging Score) and PsAMRIS (Psoriatic Arthritis Magnetic Resonance Imaging Score) for the presence and intensity of synovitis, flexor tenosynovitis, bone edema, bone erosion, periarticular inflammation, bone proliferation, and joint space narrowing. Next, odds ratios (OR) were calculated to determine the strength of the associations between these imaging features, demographic characteristics, and the outcome RA vs. PsA.

Results
PsA could be differentiated from RA by extracapsular inflammatory changes (PsAMRIS sub-score “periarticular inflammation”), with low odds for the presence of RA (OR of 0.06, p < 0.01) at all metacarpophalangeal (MCP) joints. A prediction model informed by the items that were strongest associated with the presence of RA or PsA demonstrated excellent differentiating capability with an area under the curve of 98.1%.

Conclusion
High-resolution imaging is beneficial for the identification of relevant imaging features that may assist the clinical differentiation of inflammatory conditions of the hand. At the MCP level, extracapsular inflammatory changes were strongly associated with PsA and may consequently allow the imaging differentiation of PsA and RA.
Prediction of tumour grade and survival outcome using pre-treatment PET- and MRI-derived imaging features in patients with resectable pancreatic ductal adenocarcinoma
Authors: Dunet Vincent , Halkic Nermin , Sempoux Christine , Demartines Nicolas , Montemurro Michael , Prior John O. , Schmidt Sabine 
Published: August 2020

Abstract
Objectives
To perform a correlation analysis between histopathology and imaging in patients with previously untreated pancreatic ductal adenocarcinoma (PDAC) and to determine the prognostic values of clinical, histological, and imaging parameters regarding overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS).

Methods
This single-centre study prospectively included 61 patients (32 males; median age, 68.0 years [IQR, 63.0–75.0 years]) with histologically confirmed PDAC and following surgical resection who preoperatively underwent 18F-FDG PET/CT and DW-MRI. On whole lesions, we measured, using a 42% SUVmax threshold volume of interest (VOI), the following quantitative parameters: mean and maximum standardised uptake values (SUVmean and SUVmax), total lesion glycolysis (TLG), metabolic tumour volume (MTV), mean and minimum apparent diffusion coefficient (ADCmean and ADCmin), diffusion total volume (DTV), and MTV/ADCmin ratio. Spearman’s correlation analysis was performed to assess relationships between these markers and histopathological findings from surgical specimens (stage; grade; resection quality; and vascular, perineural, and lymphatic invasion). Kaplan-Meier and Cox hazard ratio methods were used to evaluate the impacts of imaging parameters on OS (n = 41), DSS (n = 36), and PFS (n = 41).

Results
Inverse correlations between ADCmin and SUVmax (rho = − 0.34; p = 0.0071), and between SUVmean and ADCmean (rho = − 0.29; p = 0.026) were identified. ADCmin was inversely correlated with tumour grade (rho = − 0.40; p = 0.0015). MTV was an independent predictive factor for OS and DSS, while DTV was an independent predictive factor for PFS.

Conclusion
In previously untreated PDAC, ADC and SUV values are correlated. Combining PET-MRI metrics may help predict PDAC grade and patients’ survival.

Key Points
• Minimum apparent diffusion coefficient derived from DW-MRI inversely correlates with tumour grade in pancreatic ductal adenocarcinoma.
• In pancreatic ductal adenocarcinoma, metabolic tumour volume has been confirmed as a predictive factor for patients’ overall survival and disease-specific survival.
• Combining PET and MRI metrics may help predict grade and patients’ survival in pancreatic ductal adenocarcinoma.
Reiseimpfungen bei rheumatischen Erkrankungen
Authors: Welzel T. , Wörner A. , Heininger U. 
Published: August 2020

ZusammenfassungKinder und Erwachsene mit rheumatischen Erkrankungen (RE) haben nicht nur durch ihre Grunderkrankung, sondern auch durch die vielfach notwendige immunsuppressive Therapie (IT) ein erhöhtes Risiko, an bestimmten Infektionen zu erkranken. Durch die IT hat sich die Lebensqualität bei vielen Patienten mit RE verbessert, sodass ihr internationales Reiseverhalten dem gesunder Reisenden ähnelt. Eine Untersuchung deutet an, dass Patienten mit Immunsuppression oftmals unzureichend auf Reisen vorbereitet sind und ihr Impfschutz schlechter als bei Immungesunden ist. Da auch während und nach Reisen das Erkrankungsrisiko für allgemeine und reisespezifische Infektionen bei Patienten mit Immunsuppression erhöht ist, sind reisemedizinische Beratungen bei Patienten mit RE wichtig. Hier können ein Reiserücktritt oder Reisemodifikationen und spezifischer Schutz inklusive Reiseimpfungen besprochen werden. Zu den gängigen Indikationsimpfungen bei Reisen zählen Impfungen gegen Hepatitis A, Typhus, Tollwut, Meningokokken, FSME (Frühsommer-Meningoenzephalitis), saisonale Influenza, Japanische Enzephalitis, Cholera, Poliomyelitis und Gelbfieber. Bei Patienten mit RE ergibt sich die Impfindikation dabei aus der möglichen Exposition gegenüber impfpräventablen Infektionen, dem individuellen Reiseverhalten, der Schwere der möglichen Infektion unter Abwägung der Risiken, die mit der Reiseimpfung assoziiert sind. Dafür müssen auch der allgemeine Gesundheitszustand, die Aktivität und Schwere der RE und der Grad der IT beachtet werden. Allgemein gilt für Patienten mit RE und IT, dass auch bei Reiseimpfungen Lebendimpfstoffe kontraindiziert sind, während Totimpfstoffe verabreicht werden können. Da eine reduzierte Impfantwort möglich ist, können Antikörpermessungen nach der Impfserie und spezifische Impfschemata oder zusätzliche Booster bei Patienten mit RE indiziert sein.
SARS-CoV-2 & Rheuma
Authors: Leipe J. , Hoyer B. F. , Iking-Konert C. , Schulze-Koops H. , Specker C. , Krüger K. 
Published: August 2020

ZusammenfassungDie Empfehlungen des Deutschen Gesellschaft für Rheumatologie(DGRh)-Updates – welches die zu Beginn der COVID-19-Pandemie erstellte Hilfestellung zum Management von Patienten mit entzündlich rheumatischen Erkrankungen angesichts der Bedrohung durch SARS-CoV‑2 aktualisiert und erweitert – stimmen in vielen Punkten mit den Handlungsempfehlungen der amerikanischen (ACR) und europäischen Fachgesellschaften (EULAR) überein, unterscheiden sich aber auch in einigen Punkten. In diesem Artikel sollen daher Kernempfehlungen des DGRh-Updates zu den Themen Prävention von SARS-CoV-2/COVID-19, Risikoeinschätzung bei ERE sowie der Umgang mit antirheumatischen Therapien im Kontext bzw. im Vergleich zu den ACR- und EULAR-Empfehlungen diskutiert und eine Übersicht zur Risikobeurteilung einzelner antirheumatischer Medikamente gegeben werden.
Stationary distribution and cover time of sparse directed configuration models
Authors: Caputo Pietro , Quattropani Matteo 
Published: August 2020

AbstractWe consider sparse digraphs generated by the configuration model with given in-degree and out-degree sequences. We establish that with high probability the cover time is linear up to a poly-logarithmic correction. For a large class of degree sequences we determine the exponent $$\gamma \ge 1$$

γ
≥
1

of the logarithm and show that the cover time grows as $$n\log ^{\gamma }(n)$$

n

log
γ

(
n
)

, where n is the number of vertices. The results are obtained by analysing the extremal values of the stationary distribution of the digraph. In particular, we show that the stationary distribution $$\pi $$
π
is uniform up to a poly-logarithmic factor, and that for a large class of degree sequences the minimal values of $$\pi $$
π
have the form $$\frac{1}{n}\log ^{1-\gamma }(n)$$

1
n

log

1
-
γ

(
n
)

, while the maximal values of $$\pi $$
π
behave as $$\frac{1}{n}\log ^{1-\kappa }(n)$$

1
n

log

1
-
κ

(
n
)

for some other exponent $$\kappa \in [0,1]$$

κ
∈
[
0
,
1
]

. In passing, we prove tight bounds on the diameter of the digraphs and show that the latter coincides with the typical distance between two vertices.
Evaluation of a remote-controlled laparoscopic camera holder for basic laparoscopic skills acquisition: a randomized controlled trial
Authors: Amin Mohammad S. A. , Aydin Abdullatif , Abbud Nurhan , Van Cleynenbreugel Ben , Veneziano Domenico , Somani Bhaskar , Gözen Ali Serdar , Redorta Juan Palou , Khan M. Shamim , Dasgupta Prokar , Makanjuoala Jonathan , Ahmed Kamran 
Published: August 2020

Abstract
Background
Unsteady camera movement and poor visualization contribute to a difficult learning curve for laparoscopic surgery. Remote-controlled camera holders (RCHs) aim to mitigate these factors and may be used to overcome barriers to learning. Our aim was to evaluate performance benefits to laparoscopic skill acquisition in novices using a RCH.

Methods
Novices were randomized into groups using a human camera assistant (HCA) or the FreeHand v1.0 RCH and trained in the (E-BLUS) curriculum. After completing training, a surgical workload questionnaire (SURG-TLX) was issued to participants.

Results
Forty volunteers naïve in laparoscopic skill were randomized into control and intervention groups (n = 20) with intention-to-treat analysis. Each participant received up to 10 training sessions using the E-BLUS curriculum. Competency was reached in the peg transfer task in 5.5 and 7.6 sessions for the ACH and HCA groups, respectively (P = 0.015), and 3.6 and 6.8 sessions for the laparoscopic suturing task (P = 0.0004). No significance differences were achieved in the circle cutting (P = 0.18) or needle guidance tasks (P = 0.32). The RCH group experienced significantly lower workload (P = 0.014) due to lower levels of distraction (P = 0.047).

Conclusions
Remote-controlled camera holders have demonstrated the potential to significantly benefit intra-operative performance and surgical experience where camera movement is minimal. Future high-quality studies are needed to evaluate RCHs in clinical practice.

Trial registration
ISRCTN 83733979
Ein Kupfergusskuchen mit hohem Antimongehalt aus Velem/Westungarn
Authors: Haubner Roland , Strobl Susanne , Thurner Manuela , Herdits Hannes 
Published: August 2020

ZusammenfassungIn der archäologischen Sammlung des Burgenländischen Landesmuseums befindet sich ein urnenfelderzeitlicher Gusskuchen aus der Burg von Velem, einer prähistorischen befestigten Höhensiedlung auf einer Rückfallkuppe des Bernstein-Rechnitzer Fensters (BLM Inv. Nr. A154201). Velem liegt heute in Ungarn und ist seit Beginn des vorigen Jahrhunderts für seine zahlreichen metallurgischen Funde bekannt. Aufgrund des Fundortes bestand bereits die Vermutung, dass er Antimon enthalten könnte. Mittels RFA Analyse wurde ein Sb-Gehalt von 10 Gew.% nachgewiesen. Zusätzlich sind 4,5 Gew.% As, je 1,2 Gew.% S und Ag im Gusskuchen enthalten.Die Verteilung unterschiedlicher Gefüge im Gusskuchen ist sehr inhomogen. In großen Bereichen liegt dendritisch erstarrtes Cu vor. In den interdendritischen Bereichen findet man unterschiedliche Phasengemische der Elemente Cu-Sb-As‑S. Ein auffälliger Streifen aus Cu2S, der sich quer durch den Gusskuchen zieht, legt die Vermutung nahe, dass dieser Gusskuchen aus geschmolzener Arsenbronze durch Zumischen von Antimonit (Sb2S3) entstanden ist. In der geologischen Formation „Rechnitzer Fenster“ sind mehrere Fundstellen von Antimonit bekannt, die Quelle der verwendeten Arsenbronze ist jedoch unbekannt.
Physical activity and low back pain in children and adolescents: a systematic review
Authors: Kędra Agnieszka , Plandowska Magdalena , Kędra Przemysław , Czaprowski Dariusz 
Published: August 2020

Abstract
Introduction
Due to a high prevalence of low back pain (LBP) among children and adolescents, it is significant to seek effective prevention and therapeutic procedures. One idea for the programmes is a potential relation between the occurrence of LBP and the level of physical activity. The aim of this review was to analyse the current knowledge regarding the association between physical activity and LBP among children and adolescents.

Methods
Publications were retrieved by searching the following databases: PubMed, The Cochrane library, Web of Science, Medline and SportDiscus with Full Text (EBSCO). The search strategy included keywords related to physical activity and LBP. The studies included were assessed for methodological quality. PRISMA guidelines were followed for the systematic review.

Results
The total sample size of the nine included studies consisted of 75,233 subjects, with an age range of 9–19 years. All the studies were assessed to be of high quality. One cohort study and five cross-sectional studies found the association between physical activity and LBP in children and adolescents. The remaining studies found no relationship between physical activity and LBP. These findings showed that both extremes of activity levels (i.e. being very low and very high physically active) are associated with LBP.

Conclusion
There is moderate evidence for the association between physical activity and LBP in children and adolescents. The results highlight the need for continued research. It seems that for clear evaluation of the analysed association the prospective cohort studies should be conducted.
Detection of endogenous lipids in chicken feathers distinct from preen gland constituents
Authors: Zeisler-Diehl Viktoria , Al-Khutabi Eshrak Ali Ali , Kirfel Gregor , Schreiber Lukas , van Echten-Deckert Gerhild , Herzog Volker 
Published: August 2020

AbstractBird feather lipids are usually attributed to the oily secretion product of the uropygial (preen) gland. We have observed, however, that feathers exhibit a strong reaction with osmium tetroxide (OsO4), even after treatment with detergents. This leads us to postulate the existence of endogenous feather lipids distinct from preen gland lipids. In order to substantiate our hypothesis, we investigated down feathers from a 1-day-old chicken as their uropgygial gland is not functionally active. The results confirmed the osmiophilic reaction, which was concentrated in the center of barbs and strongly reduced after lipid extraction. In these lipid extracts, we identified using thin layer chromatography, cholesterol, various ceramides, glycolipids, phospholipids, and fatty acids, which closely resembled the lipid composition of the water barrier in the chicken-cornified epidermal envelope. This composition is clearly distinct from chicken uropygeal gland secretion (UGS) known to consist of fatty alcohols as part of aliphatic monoester waxes and of free, predominantly saturated, fatty acids. A filter assay showed a strong reactivity between OsO4 and the fatty acids C18:1 and C18:2 and with feather lipid extracts, but not with UGS. These observations were confirmed by gas chromatography detecting unsaturated fatty acids including C18:1 and C18:2 as well as cholesterol exclusively in chicken feathers. Our results indicate that (1) endogenous lipids are detectable in chicken feathers and distinct from UGS and (2) in analogy to the morphogenesis of the cornified envelope of chicken feather lipids that may have derived from cellular feather-precursors, apparently enduring the specific cell death during developmental feather cornification.
A characterization of supersmoothness of multivariate splines
Authors: Floater Michael S. , Hu Kaibo 
Published: August 2020

AbstractWe consider spline functions over simplicial meshes in$\mathbb {R}^{n}$ℝn. We assume that the spline pieces join together with some finite order of smoothness but the pieces themselves are infinitely smooth. Such splines can have extra orders of smoothness at a vertex, a property known assupersmoothness, which plays a role in the construction of multivariate splines and in the finite element method. In this paper, we characterize supersmoothness in terms of the degeneracy of spaces of polynomial splines over the cell of simplices sharing the vertex, and use it to determine the maximal order of supersmoothness of various cell configurations.