bluuebunny/crossref_metadata_2025 huggingface dataset:
Valve and fitting pressure losses in compressible flow systems
Authors: Hendrickson Greg
Published: May 2021

Compressible flow is commonplace in the chemical, energy and utilities sectors. The design and analysis of compressible flow systems is complicated by the relationships between the Mach number, gas density, and gas pressure. Consequently, shortcuts and rules of thumb are sometimes applied in order to simplify the calculations. One such practice is the use of head loss coefficients to estimate pressure losses through valves and fittings in the same manner for both incompressible and compressible flow calculations. The limitations of common practices involving use of head loss coefficients in compressible flow systems are explored using a direct integration method to estimate pressure losses. Several examples are provided to illustrate possible errors associated with some common practices.
Modeling the consequences of gas leakage and explosion fire in liquefied petroleum gas storage tank in Istanbul technical university, Maslak campus
Authors: Terzioglu Levent , Iskender Hikmet
Published: May 2021

One of the substances with high potential to cause damage that is used widely in chemical plants is liquefied petroleum gas (LPG). The aim of the present study is to model the consequences of leakage from a storage tank containing LPG using different scenarios. ALOHA software was used as one of the best modeling programs for identification of emergency responses required at the time of the gas leakage based on modeling results. According to ALOHA program modeling results, the area called TEEL‐3 was located within a distance of 187 m from the tank, and the threat to people in this area was determined. In case of LPG leakage from the storage tank, the concentration of LPG was about 2100 ppm which is equal to the lower explosive limit at the distance of 187 m. The consequences of combustion and explosion of LPG gas at a distance of 65 m from the storage tank were the most serious danger that threatens humans. This paper has an important role in modeling the harmful effects of the release of LPG and hazardous substances in different scenarios.
Targeting inflammation‐associated AMPK//Mfn‐2/MAPKs signaling pathways by baicalein exerts anti‐atherosclerotic action
Authors: Zhang Xinxin , Qin Yating , Ruan Weibin , Wan Xiaoning , lv Chao , He Lin , Lu Li , Guo Xiaomei
Published: May 2021

Inflammatory responses in macrophages, endothelial cells, and vascular smooth muscle cells play crucial roles in the development of atherosclerosis. Baicalein, a flavonoid phytochemical, possesses anti‐inflammatory properties, but the underlying mechanisms of its action are not fully understood. The aim of this study was to explore whether baicalein inhibited inflammatory activities in RAW264.7, HUVEC, and MOVAS cells and to analyze its underlying mechanisms. Our results showed that baicalein treatment effectively reduced the levels of IL‐6, TNF‐α, PAI‐1, and MMP‐9 released by these cells upon stimulation with Ang II or ox‐LDL. We discovered that the molecular mechanisms underlying baicalein suppression of the generation of proinflammatory cytokines were associated with the inhibition of MAPK/NF‐κB pathway activity. Moreover, Ang II and ox‐LDL intervention decreased the content of Mfn‐2 in the three types of cells, but incubation of baicalein alleviated the Ang II/ox‐LDL‐induced reduction of Mfn‐2 levels. Adv‐Mfn2 treatment not only increased the expression of Mfn‐2 but also reduced the levels of phosphorylated ERK1/2, p38, JNK, and NF‐κB, followed by a decrease in the concentrations of IL‐6, TNF‐α, PAI‐1, and MMP‐9 in the supernatant. Furthermore, our findings indicated that baicalein treatment markedly suppressed the decrease in AMPK activity induced with Ang II and ox‐LDL, and incubation with Compound C reversed the effects of baicalein on AMPK activation and Mfn‐2 expression. In conclusion, our data suggest that baicalein shows anti‐inflammatory properties, probably by activating the AMPK/Mfn‐2 axis, accompanied by inhibition of downstream MAPKs/NF‐κB signaling transduction.
An insect isoscape of UK and Ireland
Authors: Newton Jason
Published: May 2021

Rationale

The study of insect migration is problematic due to the small size of insects. Stable isotope analysis can be used to elucidate movement, either by geographic assignment of location of a species, or by simply distinguishing migrant from resident populations. There are few isoscapes of any kind in the UK/Ireland available for interrogation. Thus, I have measured stable isotope ratios (of H, C, N and S) of 299 individuals of the non‐migratory Brimstone moth (Opisthograptis luteolata) collected from 93 locations around the UK and Ireland by citizen scientists.

Methods

After removing lipids, stable isotope ratios were measured by continuous flow isotope ratio mass spectrometry, using either a conventional elemental analyser (C, N and S) or a high‐temperature, thermal conversion elemental analyser in reductive mode.

Results

Maps (isoscapes) were constructed that illustrate the stable isotope spatial distribution of this insect. These are the first isoscapes of H, C, N and S of biological samples covering both UK and Ireland.

Conclusions

The insect isoscape patterns can be explained from what we know of moth diet, climate and geology. Sulfur isotopes may be of particular use for distinguishing individuals from areas of unique geology. Isoscape patterns may (with care) predict isotope compositions of other, herbivorous, non‐aquatic, chitinous taxa. Such isoscapes, when extended beyond the UK and Ireland, would provide a useful tool to elucidate insect migration.
A hybrid learning‐based hysteresis compensation strategy for surgical robots
Authors: Gao Qian , Tan Ning , Sun Zhenglong
Published: May 2021

Background

The hysteretic forces arising from the electric cables that externally run along the robotic joints are the main disturbance to the precise parameter estimation of gravity compensation model, for the Master Tool Manipulator (MTM) of the da Vinci Research Kit (dVRK). Because such nonlinear disturbance forces and the gravitational forces are often hybrid and in the same magnitude.

Methods

A strategy is proposed to separate these two hybrid forces, and model them by individual learning‐based algorithms. A specially designed Elastic Hysteresis Neural Network model is employed to capture the hysteresis nature of disturbance forces.

Results

The experimental results show that our proposed strategy has higher compensation accuracy (78.64%–93.32%), and fewer real samples are required for model estimation (100 samples for each joint).

Conclusions

Our proposed gravity compensation strategy for the MTM of the dVRK shows great improvement over existing state‐of‐the‐arts methods through conducted comparative experiments.
Dengue fever and dengue virus in the People's Republic of China
Authors: Wu Tiantian , Wu Zhongdao , Li Yi‐Ping
Published: May 2021

Infection with dengue virus (DENV) leads to symptoms variable from dengue fever to severe dengue, which has posed a huge socioeconomic and disease burden to the world population, particularly in tropical and subtropical regions. To date, four serotypes of DENV (DENV‐1 to DENV‐4) have been identified to sustain the transmission cycle in humans. In the past decades, dengue incidences have become more frequent, and four serotypes and various genotypes have been identified in PR China. Several large‐scale dengue outbreaks and frequent local endemics occurred in the southern and coastal provinces, and the imported dengue cases accounted primarily for the initiation of the epidemics. No antiviral drug exists for dengue, and no vaccine has been approved to use in PR China, however strategies including public awareness, national reporting system of infectious diseases and public health emergencies, vector mosquito control, personal protection, and improved environmental sanitation have greatly reduced dengue prevalence. Some new technologies in vector mosquito control are emerging and being applied for dengue control. China’s territory spans tropical, subtropical, and temperate climates, hence understanding the dengue status in China will be of beneficial for the global prevention and control of dengue. Here, we review the dengue status in PR China for the past decades and the strategies emerging for dengue control.
Weighted pivot coordinates for partial least squares‐based marker discovery in high‐throughput compositional data
Authors: Štefelová Nikola , Palarea‐Albaladejo Javier , Hron Karel
Published: May 2021

High‐throughput data representing large mixtures of chemical or biological signals are ordinarily produced in the molecular sciences. Given a number of samples, partial least squares (PLS) regression is a well‐established statistical method to investigate associations between them and any continuous response variables of interest. However, technical artifacts generally make the raw signals not directly comparable between samples. Thus, data normalization is required before any meaningful scientific information can be drawn. This often allows to characterize the processed signals as compositional data where the relevant information is contained in the pairwise log‐ratios between the components of the mixture. The (log‐ratio) pivot coordinate approach facilitates the aggregation into single variables of the pairwise log‐ratios of a component to all the remaining components. This simplifies interpretability and the investigation of their relative importance but, particularly in a high‐dimensional context, the aggregated log‐ratios can easily mix up information from different underlaying processes. In this context, we propose a weighting strategy for the construction of pivot coordinates for PLS regression which draws on the correlation between response variable and pairwise log‐ratios. Using real and simulated data sets, we demonstrate that this proposal enhances the discovery of biological markers in high‐throughput compositional data.
Advances in Mesenchymal Stem Cell Therapy for Immune and Inflammatory Diseases: Use of Cell-Free Products and Human pluripotent Stem Cell-Derived Mesenchymal Stem Cells
Authors: Wang Li-Tzu , Liu Ko-Jiunn , Sytwu Huey-Kang , Yen Men-Luh , Yen B. Linju
Published: May 2021

Mesenchymal stem cell therapy (MSCT) for immune and inflammatory diseases continues to be popular based on progressive accumulation of preclinical mechanistic evidence. This has led to further expansion in clinical indications from graft rejection, autoimmune diseases, and osteoarthritis, to inflammatory liver and pulmonary diseases including COVID-19. A clear trend is the shift from using autologous to allogeneic MSCs, which can be immediately available as off-the-shelf products. In addition, new products such as cell-free exosomes and human pluripotent stem cell (hPSC)-derived MSCs are exciting developments to further prevalent use. Increasing numbers of trials have now published results in which safety of MSCT has been largely demonstrated. While reports of therapeutic endpoints are still emerging, efficacy can be seen for specific indications—including graft-vs-host-disease, strongly Th17-mediated autoimmune diseases, and osteoarthritis—which are more robustly supported by mechanistic preclinical evidence. In this review, we update and discuss outcomes in current MSCT clinical trials for immune and inflammatory disease, as well as new innovation and emerging trends in the field.
Electrochemical Radiofluorination of Small Molecules: New Advances
Authors: Hernández‐Valdés Daniel , Sadeghi Saman
Published: May 2021

The development of new 18F‐based radiopharmaceuticals constantly demands innovations in the search for new radiofluorination methods. [18F]fluoride is the simplest and most convenient chemical form of the isotope for the synthesis of 18F‐based radiopharmaceuticals. The ease of production and handling, as well as the possibility of obtaining high molar activities, makes it the preferred choice for radiofluorination. However, the use of [18F]fluoride in late‐stage radiofluorination comes with challenges, especially for the radiolabeling of electron‐rich molecules where SN2 and SNAr reactions are not suitable. New developments in fluorination chemistry have been extensively studied to overcome these difficulties. Selective electrochemical oxidation of precursors, using a controlled potential, is one method to create reactive intermediates and overcome the activation energy required for nucleophilic fluorination of electron‐rich moieties. This method has been used for years in cold fluorination of organic molecules and more recently has been adapted as an alternative to traditional radiofluorination methods. Although relatively young, this field stands out as a promising route for the synthesis of new PET probes as well as fluorinated pharmaceuticals. This review focuses on recent advances in electrochemical radiofluorination as an alternative for the late‐stage radiolabeling of organic molecules.
Post‐mortem examination of fast‐growing broilers with different degrees of identifiable gait defects
Authors: Riber Anja B. , Herskin Mette S. , Foldager Leslie , Sandercock Dale A. , Murrell Jo , Tahamtani Fernanda M.
Published: May 2021

Background: The walking ability of many broilers is characterised by slight or definite defects categorised as gait scores (GS) 1 and 2. The present study aimed to examine potential relationships between GSs and indicators of body morphology, leg pathology, tibia strength and wooden breast in Ross 308 broilers assessed as GS ≤ 2.

Methods: At 38 days of age, GS and live body weight of 179 birds was recorded. Each bird was examined post‐mortem for signs of wooden breast, contact dermatitis and a range of leg pathologies. Weights of different body parts and tibia strength were quantified.

Results: Within sex, GS increased with increasing live body weight (p = 0.020). There was a tendency for an effect of GS on prevalence of footpad dermatitis (p = 0.086) and dislocated femoral joint cartilage (p = 0.059) where both pathologies increased in frequency with increasing GS. Greater load was required to fracture tibia from GS2 than GS0 birds (p = 0.040).

Conclusions: Within this relatively small data set, no strong relationships between GS ≤ 2 and indicators of body morphology, leg pathology, tibia strength and wooden breast in Ross 308 broilers were found, except for the live terminal body weight. Further studies, involving larger data sets are required for full clarification.
Search for solutions, learning, simulation, and choice processes in suicidal behavior
Authors: Dombrovski Alexandre Y. , Hallquist Michael N.
Published: May 2021

Suicide may be viewed as an unfortunate outcome of failures in decision processes. Such failures occur when the demands of a crisis exceed a person's capacity to (i) search for options, (ii) learn and simulate possible futures, and (iii) make advantageous value‐based choices. Can individual‐level decision deficits and biases drive the progression of the suicidal crisis? Our overview of the evidence on this question is informed by clinical theory and grounded in reinforcement learning and behavioral economics. Cohort and case–control studies provide strong evidence that limited cognitive capacity and particularly impaired cognitive control are associated with suicidal behavior, imposing cognitive constraints on decision‐making. We conceptualize suicidal ideation as an element of impoverished consideration sets resulting from a search for solutions under cognitive constraints and mood‐congruent Pavlovian influences, a view supported by mostly indirect evidence. More compelling is the evidence of impaired learning in people with a history of suicidal behavior. We speculate that an inability to simulate alternative futures using one's model of the world may undermine alternative solutions in a suicidal crisis. The hypothesis supported by the strongest evidence is that the selection of suicide over alternatives is facilitated by a choice process undermined by randomness. Case–control studies using gambling tasks, armed bandits, and delay discounting support this claim. Future experimental studies will need to uncover real‐time dynamics of choice processes in suicidal people. In summary, the decision process framework sheds light on neurocognitive mechanisms that facilitate the progression of the suicidal crisis.

This article is categorized under:

Economics > Individual Decision‐Making

Psychology > Emotion and Motivation

Psychology > Learning

Neuroscience > Behavior
Functionalizing DNA nanostructures for therapeutic applications
Authors: Henry Skylar J. W. , Stephanopoulos Nicholas
Published: May 2021

Recent advances in nanotechnology have enabled rapid progress in many areas of biomedical research, including drug delivery, targeted therapies, imaging, and sensing. The emerging field of DNA nanotechnology, in which oligonucleotides are designed to self‐assemble into programmable 2D and 3D nanostructures, offers great promise for further advancements in biomedicine. DNA nanostructures present highly addressable and functionally diverse platforms for biological applications due to their ease of construction, controllable architecture and size/shape, and multiple avenues for chemical modification. Both supramolecular and covalent modification with small molecules and polymers have been shown to expand or enhance the functions of DNA nanostructures in biological contexts. These alterations include the addition of small molecule, protein, or nucleic acid moieties that enable structural stability under physiological conditions, more efficient cellular uptake and targeting, delivery of various molecular cargos, stimulus‐responsive behaviors, or modulation of a host immune response. Herein, various types of DNA nanostructure modifications and their functional consequences are examined, followed by a brief discussion of the future opportunities for functionalized DNA nanostructures as well as the barriers that must be overcome before their translational use.

This article is categorized under:

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology

Therapeutic Approaches and Drug Discovery > Emerging Technologies

Biology‐Inspired Nanomaterials > Nucleic Acid‐Based Structures
Comparing Management Programs to Reduce Red–tailed Hawk Collisions with Aircraft
Authors: Washburn Brian E. , Pullins Craig K. , Guerrant Travis L. , Martinelli Gregory J. , Beckerman Scott F.
Published: May 2021

Wildlife‐aircraft collisions (wildlife strikes) pose a serious safety risk to aircraft. Raptors (i.e., hawks and owls) are one of the most frequently struck guilds of birds within North America. Although raptors (most notably red‐tailed hawks [Buteo jamaicensis]) are commonly managed at most airports and military bases, there is no scientific information available regarding comparisons of the efficacy of raptor management programs for reducing raptor‐aircraft collisions. Therefore, we conducted a study to examine the efficacy of 2 raptor hazard management programs implemented at Chicago's O'Hare International Airport (ORD). The first raptor management program (Phase I) occurred during January 2010–June 2013 and was characterized by intensive and sustained live‐trapping and translocation efforts. The second raptor management program (Phase II) occurred during July 2013–December 2016 and involved live‐trapping and translocation of specific age classes and increased lethal removal of problematic individual hawks. Compared with Phase I, there were 47% fewer red‐tailed hawk strikes (52 in Phase I and 28 in Phase II) and 67% fewer damaging red‐tailed hawk strikes (6 in Phase I and 2 in Phase II) during Phase II of the management programs. Our findings demonstrate that airport wildlife management decisions based on scientific data and biological information can aid in reducing wildlife strikes, financial losses, and ultimately airport liability while increasing human safety. The decision matrix regarding the components of an airport raptor hazard management program involves a variety of biological, geographic, logistical, economic, and socio‐political variables. Our study provides a scientific foundation for informing such management decisions. Published 2021. This article is a U.S. Government work and is in the public domain in the USA.
A Co‐Precipitated α‐Alumina (Al2O3) used as a TL‐Micro Dosimeter
Authors: Said Fouad , Tantawy Hesham , El‐Faramawy Nabil , Abdel‐Rahman Mohamed A. E.
Published: May 2021

This study describes the preparation method of alumina (Al2O3) as a type of thermoluminescence dosimeter (TLD) to monitor gamma photons (γ‐rays) in abroad band of radioactive doses (0.5 : 2000 Gy). Alumina is selected in this study because it has a relatively low cost TL material and can be easily prepared. Aluminum oxide (Al2O3) was chemically prepared using two different methods which are the Sol‐Gel and Co‐precipitation methods. For each method, the produced alumina (Al2O3) was divided into 4 groups which was thermally treated at (400, 600, 800, 1100 °C) respectively for 6 hours for each group. The crystalline features, morphology and sample composition of the prepared samples were chemically characterized by X‐ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X‐ray (EDX). Al2O3 prepared by the Co‐precipitation method which was treated at 1100 °C (P4) was found to exhibit the highest gamma ray response compared to other samples. The deconvolution analysis showed that the main TL glow curve consisted of (5) overlapped peaks corresponding to number of traps. The linearity of the gamma response for this sample appeared in doses ranging from 1 Gy up to 200 Gy. The minimum detectable dose that can be detected by precipitated‐alumina sample (P1) was calculated mathematically to be 3.653 mGy. The fading was found to be 45.6 % after being stored for 45 days at room temperature and approximately 65 % after 90 days. This sample was reproducible according to the repeated TL results for the same sample for 5 times as their values were very close from one other with standard deviation (±σ) 0.96 %. Henceforth, Co‐precipitated α‐alumina can be used as a TL‐Micro dosimeter.
3D hybrid model of foundation‐soil‐foundation dynamic interaction
Authors: Aji Hendrawan D. B. , Wuttke Frank , Dineva Petia
Published: May 2021

3D dynamic interaction of two adjacent elastic foundations embedded in a finite layered soil region rested in a homogeneous elastic isotropic half‐space with a transient dynamic source is studied. The hybrid computational model, the corresponding numerical scheme and the accompanied software are developed, verified and inserted in detail parametric study. The hybrid approach is based on (a) finite element method (FEM) describing the scattered wave field in a finite layered soil profile with two foundations; (b) boundary element method (BEM) considering waves radiating from a dynamic transient source in elastic semi‐infinite range. The aim is to propose an efficient hybrid methodology for evaluation of the dynamic response of a foundation‐soil‐foundation system, taking into account (a) the whole wave path from the dynamic source, through the layered soil region, till the underground structures; (b) the damage state of the geological material. The BEM model is based on the 3D elastodynamic fundamental solution in Fourier domain and it is applied in order to obtain frequency‐dependent stiffness matrix and load vector of the dynamically active semi‐infinite geological zone. Once the BEM model is formulated, it is inserted as a macro‐finite element in the FEM software package ABAQUS. The frequency‐dependent FEM model describing the wave field in finite layered soil profile with two elastic foundations is realized by ABAQUS. Solutions in time domain are obtained through application of the inverse fast Fourier transform. As a final result an efficient hybrid model comprising all in one: dynamic (seismic or other type) source‐homogeneous elastic half‐space‐finite heterogeneous by layers and foundations soil profile, is presented. Parametric study illustrating the sensitivity of the dynamic field to key factors such as the type and properties of the load, the soil layering, the material properties of the far‐ and near‐field soil regions, the damaged state of the geological material and the foundation‐soil‐foundation interaction is shown and discussed.
Hardware eingebetteter Systeme
Authors: Marwedel Peter
Published: May 2021

In diesem Kapitel werden das Interface zwischen der physischen Umgebung und der Informationsverarbeitung (das Cyphy-Interface) sowie Hardware für die Verarbeitung, die Speicherung und die Kommunikation von Informationen vorgestellt. Die Notwendigkeit der Betrachtung des CyPhy-Interfaces ergibt sich dabei durch die Einbettung in ein CPS.
Systemsoftware
Authors: Marwedel Peter
Published: May 2021

Zur Bewältigung der Komplexität des Entwurfes von Anwendungen eingebetteter Systeme ist die Wiederverwendung von Komponenten ein wichtiges Hilfsmittel.
Abbildung von Anwendungen
Authors: Marwedel Peter
Published: May 2021

Ein sehr wichtiger Schritt im Entwurfsprozess ist die Abbildung von Anwendungen auf verfügbare Hardware-Plattformen. Dazu müssen wir entscheiden, auf welchem Prozessor Anwendungen (oder Teile davon) ausgeführt werden und wie sie zeitlich eingeplantwerden.
Treatment options in extra-articular distal radius fractures: a systematic review and meta-analysis
Authors: Van Oijen Guido W. , Van Lieshout Esther M. M. , Reijnders Maarten R. L. , Appalsamy Anand , Hagenaars Tjebbe , Verhofstad Michael H. J.
Published: May 2021

Purpose

This systematic literature review aimed to make a detailed overview on the clinical and functional outcomes and to get insight into the possible superiority of a treatment method for extra-articular distal radius fractures.

Methods

Embase, Medline, Cochrane Library, Web of Science, and Google Scholar were searched for studies describing treatment results. Five treatment modalities were compared: plaster cast immobilization, K-wire fixation, volar plating, external fixation, and intramedullary fixation.

Results

Out of 7,054 screened studies, 109 were included in the analysis. Overall complication rate ranged from 9% after plaster cast treatment to 18.5% after K-wire fixation. For radiographic outcomes, only volar tilt in the plaster cast group was lower than in the other groups. Apart from better grip strength after volar plating, no clear functional differences were found across treatment groups.

Conclusion

Current literature does not provide uniform evidence to prove superiority of a particular treatment method when looking at complications, re-interventions, and long-term functional outcomes.
Auswirkungen der ersten COVID‑19-Welle auf die Viszeralchirurgie
Authors: Steffani Marcella , Merz Constanze , Stöß Christian , Landau Lars , Hüser Norbert , Hartmann Daniel , Friess Helmut , Theisen Jörg , Novotny Alexander
Published: May 2021

Hintergrund

Während der ersten COVID-19-Pandemiewelle führte die Aussetzung aller elektiven Eingriffe im Zeitraum vom 15.03. bis 15.05.2020 in Deutschland zu einem Rückgang an Operationen. Die Auswirkungen auf die Zahl spezifischer Operationen in der Viszeralchirurgie sind bislang nicht bekannt.

Methoden

In diese retrospektive Studie wurden 301 Patienten eingeschlossen, die eine Cholezystektomie bzw. Appendektomie an einem Universitätsklinikum oder Krankenhaus der Grund- und Regelversorgung zwischen dem 15.03.2020 und 05.05.2020 (vs. 2018 und 2019) erhielten. Analysiert wurden die Fallzahlen und der klinische Verlauf.

Ergebnisse

Die Aussetzung des Elektivprogramms führte zu einer signifikanten Reduktion elektiver Cholezystektomien und notfallmäßiger Appendektomien. Am Universitätsklinikum reduzierte sich die Anzahl der Appendektomien von 24 im Jahr 2018 um 33 % auf 16 im Jahr 2020, die Zahl der Cholezystektomien sank von 30 um 57 % auf 13. Am Grundversorger reduzierte sich die Zahl der Appendektomiepatienten von 23 im Jahr 2018 um 48 % auf 12 im Jahr 2020, die Zahl der Cholezystektomien stieg im Jahr 2018 auf 2019 an und sank anschließend um 30 % im Jahr 2020. Die Operationsdauer, Krankenhausverweildauer und der klinische Verlauf der Patienten unterschied sich nicht signifikant zu den Vorjahreszeiträumen.

Diskussion

Der Lockdown während der ersten COVID-19-Pandemiewelle führte zu einer deutlichen Reduktion häufiger viszeralchirurgischer Eingriffe. Um die medizinische Versorgung der gesamten Bevölkerung während einer Pandemie möglichst auf hohem Niveau zu erhalten, müssen aktuelle Möglichkeiten der operativen und konservativen Therapie, unter anderem abhängig von lokalen Infektionszahlen und den individuellen Komorbiditäten der Patienten, gegeneinander abgewogen werden.
Neither critical shoulder angle nor acromion index were related with specific pathology 20 years later!
Authors: Björnsson Hallgren Hanna C. , Adolfsson Lars
Published: May 2021

Purpose

The critical shoulder angle (CSA) and the acromion index (AI) are measurements of acromial shape reported as predictors of degenerative rotator cuff tears (RCT) and glenohumeral osteoarthritis (GH OA). Whether they are the cause or effect of shoulder pathologies is uncertain since pre-morbid radiographs most often are lacking. The main aim of this study was to investigate if CSA or AI were related to the development of RCT or GH OA after 20 years. A secondary aim was to investigate if the CSA and AI had changed over time.

Methods

In the hospital archive, 273 preoperative plain shoulder radiographs were found of patients scheduled for elective surgery other than cuff repair and arthroplasty. Forty-five images fulfilled the strict criteria published by Suter and Henninger (2015) and were used to measure CSA and AI with two independent assessors. No patient had any sign of OA in the index radiographs or any information in the medical records indicating RCT. After a median of 20 (16–22) years, 30 of these patients were radiologically re-examined with bilateral true frontal views and ultrasound of the rotator cuff. There were 19 men (20 study shoulders) and 11 females (12 study shoulders).

Results

Mean age at follow-up was 56 (32–78) years. There was no correlation between CSA (r = 0.02) (n.s) or AI (r = − 0.13) (n.s) in the primary radiographs and OA at follow-up. Nor was any correlation found between index CSA (r = 0.12) (n.s) or AI (r = − 0.13) (n.s) and RCT at follow-up. Mean difference in CSA was − 1.7 (− 10–3) degrees and mean AI difference was − 0.04 (− 0.13–0.09) between the first and the second radiographs, 20 years later. Bilaterally, mean CSA was 32 and AI 0.61 at follow-up.

Conclusion

In this study, no correlation between the CSA, AI and development of OA or RCT could be found. The mean CSA and AI decreased over a 20-year period but the difference was very small. No difference was found between the study shoulders and the contralaterals. These findings question previously reported etiological associations between scapular anatomy and the development of OA or RCT and thereby the use of these calculations as the basis of treatment.

Level of evidence

III.
Quantitative Evaluation of Osteocyte Morphology and Bone Anisotropic Extracellular Matrix in Rat Femur
Authors: Ishimoto Takuya , Kawahara Keita , Matsugaki Aira , Kamioka Hiroshi , Nakano Takayoshi
Published: May 2021

Osteocytes are believed to play a crucial role in mechanosensation and mechanotransduction which are important for maintenance of mechanical integrity of bone. Recent investigations have revealed that the preferential orientation of bone extracellular matrix (ECM) mainly composed of collagen fibers and apatite crystallites is one of the important determinants of bone mechanical integrity. However, the relationship between osteocytes and ECM orientation remains unclear. In this study, the association between ECM orientation and anisotropy in the osteocyte lacuno-canalicular system, which is thought to be optimized along with the mechanical stimuli, was investigated using male rat femur. The degree of ECM orientation along the femur longitudinal axis was significantly and positively correlated with the anisotropic features of the osteocyte lacunae and canaliculi. At the femur middiaphysis, there are the osteocytes with lacunae that highly aligned along the bone long axis (principal stress direction) and canaliculi that preferentially extended perpendicular to the bone long axis, and the highest degree of apatite c-axis orientation along the bone long axis was shown. Based on these data, we propose a model in which osteocytes can change their lacuno-canalicular architecture depending on the mechanical environment so that they can become more susceptible to mechanical stimuli via fluid flow in the canalicular channel.
On subsonic near-wake flows of a space launcher configuration with various base geometries
Authors: Saile Dominik , Kühl Viktor , Gülhan Ali
Published: May 2021

Buffet/buffeting as load imposing mechanism on the base structures of space launcher has been of strong interest ever since it was found as partially responsible for the failed flight 157 of Ariane 5. Several studies suggested that the base region is most excited at Mach 0.8. A preceding study of the current series on base flow effects revealed a differing excitation in comparison to the other subsonic Mach number cases. It featured an especially pronounced excitation in the recirculation region. Thus, the current work attempts to answer the question why this case appears to be distinct. This is done by decreasing the relative nozzle length and focusing on the Reynolds stress distribution. The research question is approached by experiments in the ‘Vertical Test Section Cologne’ (VMK) on a base model with supersonic, over-expanded exhaust jet exposed to an ambient flow at Mach 0.8 and a Reynolds number of $$1.4\cdot 10^6$$

1.4
·

10
6

. Data are acquired by means of particle image velocimetry (PIV) and high-speed schlieren imaging. The results reveal that a most unfavorable configuration appears to exist, which is if the mean shear layer reattachment takes place just on the tip of the nozzle.

Graphic abstract
Reliable ligamentous stability and high return-to-sport rates after arthroscopic reduction and internal fixation of tibial eminence fractures
Authors: Lutz Patricia M. , Geyer Stephanie , Winkler Philipp W. , Irger Markus , Berthold Daniel P. , Feucht Matthias J. , Imhoff Andreas B. , Forkel Philipp
Published: May 2021

Purpose

To investigate functional and clinical outcomes, and physical activity after arthroscopic suture fixation of tibial eminence fractures with regard to postoperative stability, range of motion (ROM), complications, and return to sports.

Methods

Patients undergoing arthroscopic reduction and internal fixation (ARIF) of tibial eminence fractures using a suture fixation technique were included. Outcome was evaluated retrospectively after a minimum follow-up of 24 months using KT-1000 arthrometer measurements, clinical examination, outcome scores (Lysholm score, Tegner Activity Scale), and a questionnaire about sport activities.

Results

A total of 23 patients (44% male, 57% female) with a mean age of 25 ± 15 years were included. Mean follow-up was 57 ± 25 months. KT-1000 arthrometer measurements of anterior tibial translation revealed a mean side-to-side difference of 0.9 ± 1.0 mm. Clinical examination showed 100% normal or nearly normal anterior translation of the tibia. Two patients (9%) received an ACL reconstruction due to traumatic ACL re-instability and were, therefore, considered as failures. An extension deficit concerning hyperextension occurred in 29% of patients postoperatively. Further postoperative complications occurred in 14% of patients and included postoperative stiffness with ROM limitations and secondary dislocation of a fragment. Mean postoperative Lysholm score was 89 ± 14. Comparing pre- and postoperative values, no significant change of the Tegner Activity Scale was observed. All patients (failures excluded) returned to high impact sports activities after ARIF.

Conclusion

Excellent reliable ligamentous stability and high rates of return to high impact sports can be expected after ARIF using a suture fixation technique for type II–IV tibial eminence fractures. Complications, such as limitations in ROM, commonly occur in up to 30% after ARIF. Therefore, regular follow-up examinations remain important in this usually young patient cohort.

Level of Evidence

Level IV.
Regulation and function of CX3CR1 and its ligand CX3CL1 in kidney disease
Authors: von Vietinghoff Sibylle , Kurts Christian
Published: May 2021

Attraction, retention, and differentiation of leukocytes to and within the kidney are governed by chemokines. The chemokine CX3CL1 (fractalkine) and its receptor CX3CR1 are exemplary in this regard as they are highly expressed and further upregulated in a range of kidney diseases. CX3CL1 is chiefly produced by renal endothelium and tubular epithelium, where it promotes leukocyte attraction. Recent data suggest that in addition to established soluble mediators, cellular interactions may enhance CX3CL1 expression. The receptor CX3CR1 is essential in myeloid phagocyte homing to the kidney at homeostasis, after acute cell depletion and in inflammation. CX3CR1 and its ligand are highly regulated in human kidney diseases such as IgA nephritis, systemic lupus erythematosus, and inflammatory conditions such as transplant rejection. A mechanistic role of CX3CR1 has been established in experimental models of nephrotoxic nephritis and renal candidiasis. It is debated in fibrosis. Recent publications demonstrate a role for CX3CR1+ myeloid cells in radio-contrast-agent and sepsis-induced kidney damage. Systemically, circulating CX3CR1+ monocytes reversibly increase in individuals with renal impairment and correlate with their cardiovascular risk. In this review, we discuss role and regulatory mechanisms of the CX3CL1-CX3CR1 axis in both localized and systemic effects of renal inflammation.
LamaH | Large-Sample Data for Hydrology: Big data für die Hydrologie und Umweltwissenschaften
Authors: Klingler Christoph , Schulz Karsten , Herrnegger Mathew
Published: May 2021

„Big data“ ist zwar ein inflationär verwendetes Modewort, aber sehr umfangreiche Datensätze finden auch im Bereich der Hydrologie zunehmend Verwendung. Anhand „large-sample“ (große Stichprobe)-Untersuchungen können Einblicke in hydrologische Prozesse und den hydrologischen Kreislauf gewonnen werden, welche bei kleinräumigen Studien eventuell verwehrt bleiben würden. LamaH (Large-Sample Data for Hydrology) ist ein neuer Datensatz für „large-sample“ Untersuchungen im Zentrum von Europa. Er deckt das gesamte orographische Einzugsgebiet der oberen Donau bis zur Staatsgrenze Österreich/Slowakei sowie alle anderen Einzugsgebiete in Österreich inkl. deren Oberlieger in benachbarten Ländern ab. LamaH umfasst somit eine Fläche von rund 170.000 km2 in 9 verschiedenen Ländern und erstreckt sich dabei von Flachlandregionen mit kontinental geprägtem Klima bis hin zu hochalpinen Zonen mit ganzjähriger Schnee- und Eisbedeckung. Folglich ist eine große Diversität an verschiedenen Eigenschaften in den 859 beobachteten Einzugsgebieten vorhanden, welche anhand von über 60 verschiedenen statischen Attributen in den Kategorien Topographie, Klimatologie, Hydrologie, Landbedeckung, Vegetation, Boden sowie Geologie erfasst wird. LamaH umfasst zudem eine Sammlung an Abflusszeitreihen sowie verschiedenste meteorologische Zeitreihen. Alle Zeitreihen liegen in täglicher und stündlicher Auflösung vor, während alle meteorologischen sowie ein Großteil der Abflusszeitreihen eine Spanne von über 35 Jahren aufweisen. Die Abflusspegel sind ferner mit über 20 verschiedenen Attributen klassifiziert, wobei auch anthropogene Pegelbeeinflussungen sowie Indikatoren für Datenqualität und -vollständigkeit beschrieben werden. Die Struktur von LamaH ist grundsätzlich an jene der CAMELS-Datensätze angelehnt. Im Gegensatz dazu werden bei LamaH Daten jedoch nicht nur für unabhängige und damit teilweise sehr große Einzugsgebiete bereitgestellt, sondern auch für kleinere Zwischeneinzugsgebiete. Erstmals kann dadurch bei hydrologischen „large-sample“-Datensätzen ein großes zusammenhängendes hydrologisches Netzwerk zur Verfügung gestellt werden. Neben den Datengrundlagen, der Methodik der Datenaufbereitung und der räumlichen Verteilung ausgewählter Einzugsgebietseigenschaften werden auch etwaige Unsicherheiten bzw. Limitierungen diskutiert. Des Weiteren sind auch mögliche Anwendungsmöglichkeiten angeführt, schließlich sollte LamaH vor allem als Grundlage für weiterführende Untersuchungen dienen. LamaH kann kosten- und barrierefrei unter 10.5281/zenodo.4525244 bezogen werden.
Deep-MEG: spatiotemporal CNN features and multiband ensemble classification for predicting the early signs of Alzheimer’s disease with magnetoencephalography
Authors: Giovannetti Antonio , Susi Gianluca , Casti Paola , Mencattini Arianna , Pusil Sandra , López María Eugenia , Di Natale Corrado , Martinelli Eugenio
Published: May 2021

In this paper, we present the novel Deep-MEG approach in which image-based representations of magnetoencephalography (MEG) data are combined with ensemble classifiers based on deep convolutional neural networks. For the scope of predicting the early signs of Alzheimer’s disease (AD), functional connectivity (FC) measures between the brain bio-magnetic signals originated from spatially separated brain regions are used as MEG data representations for the analysis. After stacking the FC indicators relative to different frequency bands into multiple images, a deep transfer learning model is used to extract different sets of deep features and to derive improved classification ensembles. The proposed Deep-MEG architectures were tested on a set of resting-state MEG recordings and their corresponding magnetic resonance imaging scans, from a longitudinal study involving 87 subjects. Accuracy values of 89% and 87% were obtained, respectively, for the early prediction of AD conversion in a sample of 54 mild cognitive impairment subjects and in a sample of 87 subjects, including 33 healthy controls. These results indicate that the proposed Deep-MEG approach is a powerful tool for detecting early alterations in the spectral–temporal connectivity profiles and in their spatial relationships.
Distributed temporal graph analytics with GRADOOP
Authors: Rost Christopher , Gomez Kevin , Täschner Matthias , Fritzsche Philip , Schons Lucas , Christ Lukas , Adameit Timo , Junghanns Martin , Rahm Erhard
Published: May 2021

Temporal property graphs are graphs whose structure and properties change over time. Temporal graph datasets tend to be large due to stored historical information, asking for scalable analysis capabilities. We give a complete overview of Gradoop, a graph dataflow system for scalable, distributed analytics of temporal property graphs which has been continuously developed since 2005. Its graph model TPGM allows bitemporal modeling not only of vertices and edges but also of graph collections. A declarative analytical language called GrALa allows analysts to flexibly define analytical graph workflows by composing different operators that support temporal graph analysis. Built on a distributed dataflow system, large temporal graphs can be processed on a shared-nothing cluster. We present the system architecture of Gradoop, its data model TPGM with composable temporal graph operators, like snapshot, difference, pattern matching, graph grouping and several implementation details. We evaluate the performance and scalability of selected operators and a composed workflow for synthetic and real-world temporal graphs with up to 283 M vertices and 1.8 B edges, and a graph lifetime of about 8 years with up to 20 M new edges per year. We also reflect on lessons learned from the Gradoop effort.
Learning-free pattern detection for manuscript research:
Authors: Mohammed Hussein , Märgner Volker , Ciotti Giovanni
Published: May 2021

Automatic pattern detection has become increasingly important for scholars in the humanities as the number of manuscripts that have been digitised has grown. Most of the state-of-the-art methods used for pattern detection depend on the availability of a large number of training samples, which are typically not available in the humanities as they involve tedious manual annotation by researchers (e.g. marking the location and size of words, drawings, seals and so on). This makes the applicability of such methods very limited within the field of manuscript research. We propose a learning-free approach based on a state-of-the-art Naïve Bayes Nearest-Neighbour classifier for the task of pattern detection in manuscript images. The method has already been successfully applied to an actual research question from South Asian studies about palm-leaf manuscripts. Furthermore, state-of-the-art results have been achieved on two extremely challenging datasets, namely the AMADI_LontarSet dataset of handwriting on palm leaves for word-spotting and the DocExplore dataset of medieval manuscripts for pattern detection. A performance analysis is provided as well in order to facilitate later comparisons by other researchers. Finally, an easy-to-use implementation of the proposed method is developed as a software tool and made freely available.
Validation of tissue factor pathway inhibitor 2 as a specific biomarker for preoperative prediction of clear cell carcinoma of the ovary
Authors: Miyagi Etsuko , Arakawa Noriaki , Sakamaki Kentaro , Yokota Naho Ruiz , Yamanaka Takeharu , Yamada Yuki , Yamaguchi Satoshi , Nagao Shoji , Hirashima Yasuyuki , Kasamatsu Yuka , Kato Hisamori , Mogami Tae , Miyagi Yohei , Kobayashi Hiroshi
Published: May 2021

Background

Tissue factor pathway inhibitor 2 (TFPI2) is a novel serum biomarker that discriminates ovarian clear cell carcinoma (CCC) from borderline ovarian tumors (BOTs) and non-clear cell epithelial ovarian cancers (EOCs). Here, we examined the performance of TFPI2 for preoperative diagnosis of CCC.

Methods

Serum samples were obtained preoperatively from patients with ovarian masses, who needed surgical treatment at five hospitals in Japan. The diagnostic powers of TFPI2 and cancer antigen 125 (CA125) serum levels to discriminate CCC from BOTs, other EOCs, and benign lesions were compared.

Results

A total of 351 patients including 69 CCCs were analyzed. Serum TFPI2 levels were significantly higher in CCC patients (mean ± SD, 508.2 ± 812.0 pg/mL) than in patients with benign lesions (154.7 ± 46.5), BOTs (181 ± 95.5) and other EOCs (265.4 ± 289.1). TFPI2 had a high diagnostic specificity for CCC (79.5%). In patients with benign ovarian endometriosis, no patient was positive for TFPI2, but 71.4% (15/21) were CA125 positive. TFPI2 showed good performance in discriminating stage II–IV CCC from BOTs and other EOCs (AUC 0.815 for TFPI2 versus 0.505 for CA125) or endometriosis (AUC 0.957 for TFPI2 versus 0.748 for CA125). The diagnostic sensitivity of TFPI2 to discriminate CCC from BOTs and other EOCs was improved from 43.5 to 71.0% when combined with CA125.

Conclusions

High specificity of TFPI2 for preoperative detection of CCC was verified with the defined cutoff level of TFPI2 in clinical practice. TFPI2 and CA125 may contribute substantially to precise prediction of intractable CCC.
A New Technique for Preserving Conservation Laws
Authors: Frasca-Caccia Gianluca , Hydon Peter E.
Published: May 2021

This paper introduces a new symbolic-numeric strategy for finding semidiscretizations of a given PDE that preserve multiple local conservation laws. We prove that for one spatial dimension, various one-step time integrators from the literature preserve fully discrete local conservation laws whose densities are either quadratic or a Hamiltonian. The approach generalizes to time integrators with more steps and conservation laws of other kinds; higher-dimensional PDEs can be treated by iterating the new strategy. We use the Boussinesq equation as a benchmark and introduce new families of schemes of order two and four that preserve three conservation laws. We show that the new technique is practicable for PDEs with three dependent variables, introducing as an example new families of second-order schemes for the potential Kadomtsev–Petviashvili equation.