bluuebunny/crossref_metadata_2025 huggingface dataset:
Activity and participation in stroke survivors in a low‐income setting: A cross‐sectional study
Authors: Mwaka‐Rutare Claudel , Perreault Kadija , Abedi‐Mukutenga Pamphyle , Masuga‐Musafiri Willy , Batcho Charles Sèbiyo
Published: April 2020

Objectives

To describe patients' activity and participation levels and to compare these levels across different groups of stroke survivors according to their walking speed (WS).

Methods

In this cross‐sectional study, 67 stroke survivors (43 men, mean age: 58.4 ± 12.9 years old) were assessed using the stroke impairment assessment set (SIAS), ACTIVLIM‐Stroke, 10‐m walk test (10MWT), 6‐min walk test (6MWT) and Reintegration to Normal Living Index (RNLI). The sample was afterwards split into three WS sub‐groups (<0.4 m/s, 0.4–0.8 m/s and >0.8 m/s) based on 10MWT scores.

Results

ACTIVLIM‐Stroke, 10MWT and 6MWT mean scores (±SD) were, respectively, 69.4 ± 20.2%, 0.9 ± 0.6 m/s and 282.1 ± 182 m. RNLI median score (range) was 5 (0–20). Sub‐group analyses indicated that 26.9% (n = 18) obtained WS < 0.4 m/s, 13.4% (n = 9) WS between 0.4 and 0.8 m/s, and 59.7% (n = 40) WS > 0.8 m/s. Significant differences (p < .001) were found between WS sub‐groups for both activity and participation.

Conclusion

Stroke survivors in Kinshasa presented a good performance for basic‐activities of daily life (basic‐ADLs). However, some of them still had difficulties with some community activities. Differences in WS seemed to discriminate well stroke survivors in terms of activity and participation, since the higher WS, the more they performed in basic‐ADLs, walking distance and participation, and inversely.
Plant growth‐promoting rhizobacteria: a novel management strategy for Meloidogyne incognita on turfgrass
Authors: Groover Will , Held David , Lawrence Kathy , Carson Kendra
Published: April 2020

BACKGROUND

Meloidogyne spp., root‐knot nematodes, are among the most economically important plant‐parasitic nematodes in turfgrass in the United States. Only a few nematicides are available or efficacious for plant‐parasitic nematodes in turfgrass in the United States, and recent work has demonstrated the potential for microbial control of root‐knot nematodes in field crops. The objectives of this study were to evaluate the efficacy of 104 plant growth‐promoting rhizobacteria (PGPR) strains isolated from grasses in Alabama against M. incognita in vitro, and their ability to manage plant‐parasitic nematodes in the glasshouse and microplot settings.

RESULTS

In vitro mortality ranged from 0.9% to 94.6% by all PGPR strains screened. Ten individual PGPR strains and one three‐strain blend (a total of 13 PGPR strains) were advanced to glasshouse and microplot screening. In the glasshouse, six of the 11 PGPR treatments significantly reduced M. incognita population density, with a few strains also promoting some root growth. In the microplot, five of the 11 PGPR treatments significantly reduced M. incognita population density.

CONCLUSION

Of these strains, 11 were identified as Bacillus spp., one as Stenotrophomonas rhizophila and one as Paenibacillus sonchi. Eight of these strains also were found to have nitrogenase activity, and seven had the ability to produce siderophores, showing a potential mechanism for growth promotion. Overall, results indicate that multiple strains of Bacillus spp. and one strain of S. rhizophila have the potential to reduce M. incognita population density and enhance turfgrass root growth. © 2020 Society of Chemical Industry
Negative Differential Resistance and Hysteresis in Self‐Assembled Nanoscale Networks with Tunable Molecule‐to‐Nanoparticle Ratios
Authors: Venkataraman Anusha , Amadi Eberechukwu V. , Zaborniak Tristan S. M. , Zhang Po , Papadopoulos Chris
Published: April 2020

Electronic transport is investigated through self‐assembled benzenedithiol–gold nanoparticle networks with tunable molecule‐to‐particle ratios (1:5–50:1) deposited between planar electrodes. Two‐terminal current–voltage measurements of the networks display linear behavior at low bias, which is described using a circuit model that accounts for different network morphologies, tunable via molecule‐to‐nanoparticle ratio, and defects. At larger biases, nonlinear negative differential resistance and hysteresis behavior are observed for different molecular concentrations, which can be attributed to a combination of field‐assisted tunneling and charge trapping occurring in the nanoscale networks. The directed self‐assembly of benzenedithiol–metal nanoparticle molecular electronic networks is suggested for molecular integrated circuits in applications such as memory, switching, hardware security, and computing.
Therapeutic potentials of curcumin in the treatment of non‐small‐cell lung carcinoma
Authors: Salehi Mahsa , Movahedpour Ahmad , Tayarani Alireza , Shabaninejad Zahra , Pourhanifeh Mohammad H. , Mortezapour Erfan , Nickdasti Ali , Mottaghi Reza , Davoodabadi Abdolhossein , Khan Haroon , Savardashtaki Amir , Mirzaei Hamed
Published: April 2020

Non‐small‐cell lung carcinoma (NSCLC) is one of the most lethal malignancies that include more than 80% of lung cancer cases worldwide. During the past decades, plants and plant‐derived products have attracted great interest in the treatment of various human diseases. Curcumin, the turmeric isolated natural phenolic compound, has shown a promising chemo‐preventive and anticancer agent. Numerous studies have shown that curcumin delays the initiation and progression of NSCLC by affecting a wide range of molecular targets and cell signalling pathways including NF‐kB, Akt, MAPKS, BCL‐2, ROS and microRNAs (miRNAs). However, the poor oral bioavailability and low chemical stability of curcumin remain as major challenges in the utilisation of this compound as a therapeutic agent. Different analogs of curcumin and new delivery systems (e.g., micelles, nanoparticles and liposomes) provided promising solutions to overcome these obstacles and improve curcumin pharmacokinetic profile. The present review focuses on current reported studies about anti‐NSCLC effects of curcumin. NSCLC involved miRNAs whose expression is regulated by curcumin has also been discussed. Furthermore, recent researches on the use of curcumin analogs and delivery systems to enhance the curcumin benefits in NSCLC are also described.
Strangely attractive: Collaboration and feedback in the field of molecular magnetism
Authors: Goodwin Conrad A. P. , Ortu Fabrizio , Reta Daniel
Published: April 2020

The fluid synergy between experimentalists and theoreticians has, for decades, led to a deeper understanding of the processes that govern single‐molecule magnets. This approach has allowed for the establishment of proven design criteria for the control of magnetic properties through molecular architecture and the development of new magnetic measurement techniques and innovative computational methodologies. Here, we give an account of the experimental and theoretical joint endeavor carried out as part of the synthesis group led by David Mills and the computational/theoretical team led by Nicholas Chilton, together with colleagues in synthetic f‐element chemistry and magnetism at the University of Manchester. In addition, we provide a personal perspective on collaborative work in molecular magnetism and how such collaborations are essential for advancing the field further.
Construction of Bimetallic Selenides Encapsulated in Nitrogen/Sulfur Co‐Doped Hollow Carbon Nanospheres for High‐Performance Sodium/Potassium‐Ion Half/Full Batteries
Authors: Sun Zhonghui , Wu Xing‐Long , Xu Jianan , Qu Dongyang , Zhao Bolin , Gu Zhenyi , Li Wenhao , Liang Haojie , Gao Lifang , Fan Yingying , Zhou Kai , Han Dongxue , Gan Shiyu , Zhang Yuwei , Niu Li
Published: April 2020

Metallic selenides have been widely investigated as promising electrode materials for metal‐ion batteries based on their relatively high theoretical capacity. However, rapid capacity decay and structural collapse resulting from the larger‐sized Na+/K+ greatly hamper their application. Herein, a bimetallic selenide (MoSe2/CoSe2) encapsulated in nitrogen, sulfur‐codoped hollow carbon nanospheres interconnected reduced graphene oxide nanosheets (rGO@MCSe) are successfully designed as advanced anode materials for Na/K‐ion batteries. As expected, the significant pseudocapacitive charge storage behavior substantially contributes to superior rate capability. Specifically, it achieves a high reversible specific capacity of 311 mAh g−1 at 10 A g−1 in NIBs and 310 mAh g−1 at 5 A g−1 in KIBs. A combination of ex situ X‐ray diffraction, Raman spectroscopy, and transmission electron microscopy tests reveals the phase transition of rGO@MCSe in NIBs/KIBs. Unexpectedly, they show quite different Na+/K+ insertion/extraction reaction mechanisms for both cells, maybe due to more sluggish K+ diffusion kinetics than that of Na+. More significantly, it shows excellent energy storage properties in Na/K‐ion full cells when coupled with Na3V2(PO4)2O2F and PTCDA@450 °C cathodes. This work offers an advanced electrode construction guidance for the development of high‐performance energy storage devices.
Hierarchical 3D Oxygenated Cobalt Molybdenum Selenide Nanosheets as Robust Trifunctional Catalyst for Water Splitting and Zinc–Air Batteries
Authors: Prabhakaran Sampath , Balamurugan Jayaraman , Kim Nam Hoon , Lee Joong Hee
Published: April 2020

The development of hierarchical nanostructures with highly active and durable multifunctional catalysts has a new significance in the context of new energy technologies of water splitting and metal–air batteries. Herein, a strategy is demonstrated to construct a 3D hierarchical oxygenated cobalt molybdenum selenide (O‐Co1−xMoxSe2) series with attractive nanoarchitectures, which are fabricated by a simple and cost‐effective hydrothermal process followed by an exclusive ion‐exchange process. Owing to its highly electroactive sites with numerous nanoporous networks and plentiful oxygen vacancies, the optimal O‐Co0.5Mo0.5Se2 could catalyze the hydrogen evolution reaction and oxygen evolution reaction effectively with a low overpotential of ≈102 and 189 mV, at a current density of 10 mA cm−2, respectively, and exceptional durability. Most importantly, the O‐Co0.5Mo0.5Se2||O‐Co0.5Mo0.5Se2 water splitting device only entails a voltage of ≈1.53 V at a current density of 10 mA cm−2, which is much better than benchmark Pt/C||RuO2 (≈1.56 V). Furthermore, O‐Co0.5Mo0.5Se2 air cathode‐based zinc–air batteries exhibit an excellent power density of 120.28 mW cm−2 and exceptional cycling stability for 60 h, superior to those of state‐of‐art Pt/C+RuO2 pair‐based zinc–air batteries. The present study provides a strategy to design hierarchical 3D oxygenated bimetallic selenide‐based multifunctional catalysts for energy conversion and storage systems.
Self‐Assembled Ruddlesden–Popper/Perovskite Hybrid with Lattice‐Oxygen Activation as a Superior Oxygen Evolution Electrocatalyst
Authors: Zhu Yinlong , Lin Qian , Hu Zhiwei , Chen Yubo , Yin Yichun , Tahini Hassan A. , Lin Hong‐Ji , Chen Chien‐Te , Zhang Xiwang , Shao Zongping , Wang Huanting
Published: April 2020

The oxygen evolution reaction (OER) is pivotal in multiple gas‐involved energy conversion technologies, such as water splitting, rechargeable metal–air batteries, and CO2/N2electrolysis. Emerging anion‐redox chemistry provides exciting opportunities for boosting catalytic activity, and thus mastering lattice‐oxygen activation of metal oxides and identifying the origins are crucial for the development of advanced catalysts. Here, a strategy to activate surface lattice‐oxygen sites for OER catalysis via constructing a Ruddlesden–Popper/perovskite hybrid, which is prepared by a facile one‐pot self‐assembly method, is developed. As a proof‐of‐concept, the unique hybrid catalyst (RP/P‐LSCF) consists of a dominated Ruddlesden–Popper phase LaSr3Co1.5Fe1.5O10‐δ(RP‐LSCF) and second perovskite phase La0.25Sr0.75Co0.5Fe0.5O3‐δ(P‐LSCF), displaying exceptional OER activity. The RP/P‐LSCF achieves 10 mA cm−2at a low overpotential of only 324 mV in 0.1mKOH, surpassing the benchmark RuO2and various state‐of‐the‐art metal oxides ever reported for OER, while showing significantly higher activity and stability than single RP‐LSCF oxide. The high catalytic performance for RP/P‐LSCF is attributed to the strong metal–oxygen covalency and high oxygen‐ion diffusion rate resulting from the phase mixture, which likely triggers the surface lattice‐oxygen activation to participate in OER. The success of Ruddlesden–Popper/perovskite hybrid construction creates a new direction to design advanced catalysts for various energy applications.
Boosting O2•− Photogeneration via Promoting Intersystem‐Crossing and Electron‐Donating Efficiency of Aza‐BODIPY‐Based Nanoplatforms for Hypoxic‐Tumor Photodynamic Therapy
Authors: Chen Dapeng , Wang Zhichao , Dai Hanming , Lv Xinyi , Ma Qianli , Yang Da‐Peng , Shao Jinjun , Xu Zhigang , Dong Xiaochen
Published: April 2020

Tumor hypoxia severely impedes the therapeutic efficacy of type II photodynamic therapy (PDT) depending on singlet oxygen (1O2) generation. To combat hypoxic tumors, herein, a new approach is devised to boost superoxide radical (O2•−) photogeneration for type I PDT. Heavy atoms are introduced onto aza‐BODIPY molecules (iodine substituted butoxy‐aza‐BODIPY, IBAB) to promote their intersystem‐crossing (ISC) ability. Meanwhile, methoxy‐poly(ethylene glycol)‐b‐poly(2‐(diisopropylamino) ethyl methacrylate) (mPEG‐PPDA) with enhanced electron‐donating efficiency is employed as a coating matrix to encapsulate IBAB, thereby obtaining amphiphilic aza‐BODIPY nanoplatforms (PPIAB NPs). Under irradiation, triplet‐state IBAB in PPIAB NPs is efficiently generated from singlet state favored by the elevated ISC ability. The electron‐rich environment provided by mPEG‐PPDA can donate triplet‐state IBAB with one electron to form charge‐separated‐state IBAB, which in turn transfers electron to O2 for O2•− production. Significantly, owing to recyclable O2 generated by disproportionation or Harber–Weiss/Fenton reaction, prominent O2•− is generated by PPIAB NPs even in a severe hypoxic environment (2% O2), enabling superior therapeutic efficacy (96.2% tumor‐inhibition rate) over NPs not following this strategy. Thus, the proof‐of‐concept design of ISC‐enhanced and electron‐rich polymer encapsulating PPIAB NPs illuminates the path to preparing O2•− photogenerator for hypoxic cancer treatment.
Conodont faunas across the Kasimovian–Gzhelian boundary (Late Pennsylvanian) in South China and implications for the selection of the stratotype for the base of the global Gzhelian Stage
Authors: Qi Yuping , Barrick James E. , Hogancamp Nicholas J. , Chen Jitao , Hu Keyi , Wang Qiulai , Wang Xiangdong
Published: April 2020

The upper Pennsylvanian Naqing and Narao carbonate successions were deposited in intra‐platform slope‐to‐basinal settings across the Kasimovian–Gzhelian boundary in Guizhou, South China. Conodont faunas consist of a mixture of the endemic taxa of theIdiognathodus luodianensisgroup and cosmopolitan species of theI. simulatorgroup. TheI. luodianensisgroup includes the new speciesI. fengtingensis,I. luodianensis,I. naqingensisandI. naraoensis. On platform landmark analysis the species of theI. luodianensisgroup differ in morphological features from co‐occurring species of theI. simulatorgroup. Both groups display similar increasing asymmetry in P1element pairs across the Kasimovian–Gzhelian boundary, as recognized on the basis of the first occurrence ofI. simulator. Many KasimovianIdiognathodusspecies disappear and several Gzhelian species first appear withI. simulator, including two new species ofStreptognathodus:S. nemyrovskaeandS. zhihaoi. Just below the base of the Gzhelian, carbonate δ13C falls from 4‰ to 2‰ in both sections. The combination of an abrupt faunal turnover immediately above the prominent negative δ13C excursion might represent an oceanic event in South China, perhaps recognizable on a global scale. One of these two South China sections may be the best location to place theGSSPfor the base of the Gzhelian Stage.
On a system–environment relationship in scientific inquiry: A response to ‘Definition of System’ by A. D. Hall and R. E. Fagen
Authors: Kasianiuk Krzysztof
Published: April 2020

In one of early accounts of system–environment relationship, A. D. Hall and R. E. Fagen presented a thesis that specification of environment could be as difficult as specification of system. However, since that moment, many researchers have not put similar emphasis on specification of environment as they have put on specification of system. In this article, it is argued that system and environment should be understood either as ‘parts’ or ‘aspects’ of nature, which translates into two qualities of their relationship—‘interactivity’ and ‘transactivity’. Moreover, the quality of system–environment relationship influences modelling and explanatory strategies within scientific inquiry.
Platinum nanoparticles induced genotoxicity and apoptotic activity in human normal and cancer hepatic cells via oxidative stress‐mediated Bax/Bcl‐2 and caspase‐3 expression
Authors: Almarzoug Mohammed H. A. , Ali Daoud , Alarifi Saud , Alkahtani Saad , Alhadheq Abdullah M.
Published: April 2020

Platinum nanoparticles (PtNPs) attract much attention due to their excellent biocompatibility and catalytic properties, but their toxic effects on normal (CHANG) and cancerous (HuH‐7) human liver cells are meagre. The cytotoxic and apoptotic effects of PtNPs (average size, 3 nm) were determined in CHANG and HuH‐7 cells. After treating these cells were with PtNPs (10, 50, 100, 200, and 300 μg/mL) for 24 and 48 hours, we observed dose‐ and time‐dependent cytotoxicity, as evaluated by using (3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5‐diphenyltetrazolium bromide, a tetrazole) (MTT) and neutral red uptake (NRU) assays. The production of reactive oxygen species (ROS) was increased in both cells after treatment with the above dose of PtNPs for 24 and 48 hours. Determination of morphological changes of cells, chromosome condensation, mitochondrial membrane potential, and caspase‐3 assays showed that PtNPs induce cytotoxicity and apoptosis in CHANG and HuH‐7 cells by altering the cell morphology and density, increasing cell population in apoptosis, and causing chromosome condensation. Furthermore, we have studied fragmentation of DNA using alkaline single cell gel electrophoresis and expression of apoptotic genes by real‐time PCR (RT‐PCR). The percentage of DNA fragmentation was more at 300 μg/mL for 48 hours in both cells, but slightly more fragmentation was found in HuH‐7 relative to CHANG cells. Considering all of the above parameters, PtNPs elicited cytotoxicity on CHANG and HuH‐7 cells by blocking cell proliferation and inducing apoptosis. Thus this study may be useful in in vitro laboratory studies using cell lines for screening the genotoxic and apoptotic potential of nanoparticles.
The Coupled Model Intercomparison Project: History, uses, and structural effects on climate research
Authors: Touzé‐Peiffer Ludovic , Barberousse Anouk , Le Treut Hervé
Published: April 2020

The results of the sixth phase of the coupled model intercomparison project (CMIP) are currently being analyzed and will form the basis of the IPCC Sixth Assessment Report. Since its creation in the mid‐1990s, CMIP has had an increasing influence on climate research. While the principle behind it has always remained the same—comparing different climate models under similar conditions—its design and motivations have evolved significantly over the phases of the project. This evolution is closely linked to that of the IPCC since, historically as well as today, the results of CMIP have played a major role in the Panel's reports. This role increased the visibility of CMIP. Over time, more and more people started to be interested in CMIP and to analyze its results. Despite this success, the way CMIP is used today raises methodological issues. In fact, CMIP has promoted a particular way of doing climate research, centered on a single tool–Global Coupled Models (GCMs)–and creating a gap between model developers and model users. Due to the debates regarding the interpretation of multi‐model ensembles and the validation of GCMs, whether the emphasis on this particular way of studying climate is serving the progress of climate science is questionable.

This article is categorized under:

Climate Models and Modeling > Knowledge Generation with Models
Embedding Alkyldiamine into Layered α‐Titanium Phosphate via Direct‐Ion Exchange and its Application in EuIII Removal from Water
Authors: Peng Wen‐Jing , Wang Xin‐Guo , Wang Ming‐Ming , Wang Yan‐Ji , Cheng Qing‐Yan
Published: April 2020

Diamine‐pillared α‐titanium phosphate (α‐TiP) was prepared via direct ion exchange method. Moreover, 1,3‐propanediamine, as the pillaring agent, was used to investigate the effect of pH, content and temperature on the interlayer distance of α‐TiP. The structure and properties of the samples were characterized by X‐ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT‐IR), Field Emission Scanning Electron Microscopy (SEM), and Differential Thermal Analysis (TG). The results show that the interlayer distance of α‐TiP was enlarged from 7.6 Å to 16.18 Å as the carbon chain of the intercalating diamine increased from (NH2(CH2)nNH2) (n = 2 to 7). The layer space structure consists of monomolecular alkyl chains with an average tilt angle of 75.6°. The uptake values for these five alkyldiamine cations were 3.780, 3.261, 2.443, 2.175, and 1.954 mmol, per gram of TiP, respectively. Also, we found that the direct ion exchange method is more effective in a weak acidic environment. The variation of interlayer distance was a consecutive process, and unaffected by temperature. The 1,3‐propanediamine intercalation product (α‐TiPPda) showed excellent performance towards EuIII adsorption in water with removal efficiencies ≥ 99 %.
Co-location of Space Geodetic Techniques: Studies on Intra-Technique Short Baselines
Authors: Pinzón Iván Herrera , Rothacher Markus
Published: April 2020

The goal of the project “Co-location of Space Geodetic Techniques on Ground and in Space”, in the DFG funded research unit on reference systems and founded by the Swiss National Foundation (SNF), is the improvement of existing and the establishment of new ties between the space geodetic techniques, together with the assessment and reduction of technique-specific biases. To achieve this, the wealth of co-located instruments at the Geodetic Observatory Wettzell (Germany) are used, where systematic errors in the space geodetic techniques can be detected, assessed and removed on very short, well-known baselines. Within this paper we summarise results for three intra-technique co-location experiments in Wettzell. Firstly, an assessment of the GNSS to GNSS baselines in relation to the surveyed local ties shows discrepancies of up to 9 mm, for solutions based on the ionosphere-free linear combination. Secondly, an analysis of the short VLBI baseline shows that the use of a clock tie achieves a sub-mm agreement with respect to the local tie. And finally, initial results on the usage of differencing approaches on the short SLR baseline show that double-difference residuals are within ±4 mm. The results of this work show the potential of intra-technique studies on short baselines for the understanding of technique-specific biases and errors and for the monitoring of local ties.
The cosmological bootstrap: inflationary correlators from symmetries and singularities
Authors: Arkani-Hamed Nima , Baumann Daniel , Lee Hayden , Pimentel Guilherme L.
Published: April 2020

Abstract

Scattering amplitudes at weak coupling are highly constrained by Lorentz invariance, locality and unitarity, and depend on model details only through coupling constants and the particle content of the theory. For example, four-particle amplitudes are analytic for contact interactions and have simple poles with appropriately positive residues for tree-level exchange. In this paper, we develop an understanding of inflationary correlators which parallels that of flat-space scattering amplitudes. Specifically, we study slow-roll inflation with weak couplings to extra massive particles, for which all correlation functions are controlled by an approximate conformal symmetry on the boundary of the spacetime. After systematically classifying all possible contact terms in de Sitter space, we derive an analytic expression for the four-point function of conformally coupled scalars mediated by the tree-level exchange of massive scalars. Conformal symmetry implies that the correlator satisfies a pair of differential equations with respect to spatial momenta, encoding bulk time evolution in purely boundary terms. The absence of unphysical singularities (and the correct normalization of physical ones) completely fixes this correlator. Moreover, a “spin-raising” operator relates it to the correlators associated with the exchange of particles with spin, while “weight-shifting” operators map it to the four-point function of massless scalars. We explain how these de Sitter four-point functions can be perturbed to obtain inflationary three-point functions. Using our formalism, we reproduce many classic results in the literature, such as the three-point function of slow-roll inflation, and provide a complete classification of all inflationary three- and four-point functions arising from weakly broken conformal symmetry. Remarkably, the inflationary bispectrum associated with the exchange of particles with arbitrary spin is completely characterized by the soft limit of the simplest scalar-exchange four-point function of conformally coupled scalars and a series of contact terms. Finally, we demonstrate that the inflationary correlators contain flat-space scattering amplitudes via a suitable analytic continuation of the external momenta, which can also be directly connected with the signals for particle production seen in the squeezed limit.
Weiterhin keine Evidenz für Drainagen in der Bariatrie
Authors: Seyfried Steffen
Published: April 2020

Hintergrund

Registerdaten zeigen, dass eine Drainageneinlage im Rahmen bariatrischer Operationen immer noch gängige Praxis in vielen chirurgischen Abteilungen ist. Retrospektive Studien und eine Übersichtsarbeit konnten zeigen, dass die routinemäßige Einlage einer Drainage im Rahmen bariatrischer Operationen nutzlos und potenziell auch gefährdend ist. In der Literatur konnte aufgrund fehlender randomisierter kontrollierter Studien keine ausreichende Evidenz zu diesem Thema geschaffen werden.

Ziel

Um den Nutzen von Drainagen bei bariatrischen Eingriffen weiter zu hinterfragen, haben wir unsere prospektiv erhobene Datenbank von Patienten, die zwischen Januar 2010 und Juni 2016 eine Schlauchmagenanlage (SG) oder einen Roux-en-Y-Magenbypass (RYGB) erhielten, retrospektiv ausgewertet.

Setting

Deutsches Universitätsklinikum

Methoden

Während des Untersuchungszeitraums wurden insgesamt 361 Operationen (219 Magenbypass- und 142 Schlauchmagenoperationen) durchgeführt. Eine Änderung unseres internen Behandlungspfades in Bezug auf die Platzierung von Drainagen im Jahr 2013 führte dabei zu zwei Gruppen: eine, bei der routinemäßig Drainagen bei Operationen platziert wurden (166), und eine bei denen keine Drainage angelegt wurde (195). Die demografischen Daten wurden mithilfe multipler Regressionsanalyse statistisch zwischen den beiden Gruppen adjustiert. Wir verglichen die Operationsergebnisse und die 30-Tage-Morbidität. Komplikationen wurden nach der Clavien-Dindo-Klassifikation bewertet.

Ergebnisse

In der Gruppe ohne Drainage hatten 7 Patienten Komplikationen. In der Drainagegruppe traten 6 Komplikationen auf. Die Insuffizienzraten und Reoperationsraten zwischen den Gruppen waren statistisch nicht unterschiedlich. Im Durchschnitt wurde der postoperative Aufenthalt bei Patienten mit Drainage um 1,3 Tage verlängert. Die multivariate Analyse zeigte, dass die Platzierung von Drainagen der höchste Risikofaktor für einen längeren Krankenhausaufenthalt ist.

Schlussfolgerung

Drainagenanlagen im Rahmen bariatrischer Eingriffe sollten eine individuelle Überlegung sein. Von der routinemäßigen Verwendung sollte abgeraten werden.
Signaling lipids as diagnostic biomarkers for ocular surface cicatrizing conjunctivitis
Authors: Di Zazzo Antonio , Yang Wei , Coassin Marco , Micera Alessandra , Antonini Marco , Piccinni Fabrizio , De Piano Maria , Kohler Isabelle , Harms Amy C. , Hankemeier Thomas , Boinini Stefano , Mashaghi Alireza
Published: April 2020

Metabolomics has been applied to diagnose diseases, predict disease progression, and design therapeutic strategies in various areas of medicine. However, it remains to be applied to the ocular surface diseases, where biological samples are often of limited quantities. We successfully performed proof-of-concept metabolomics assessment of volume-limited cytology samples from a clinical form of chronic inflammatory cicatrizing conjunctivitis, i.e., ocular MMP and discovered metabolic changes of signaling lipid mediators upon disease onset and progression. The metabolomics assessment revealed active oxylipins, lysophospholipids, fatty acids, and endocannabinoids alterations, from which potential biomarkers linked to inflammatory processes were identified. Possible underlying mechanisms such as dysregulated enzyme activities (e.g., lipoxygenases, cytochrome P450, and phospholipases) were suggested which may be considered as potential therapeutic targets in future studies.

Key messages

Metabolic profile of the ocular surface can be measured using impression cytology samples.

Metabolomics analysis of ocular pemphigoid is presented for the first time.

The metabolomics assessment of OCP patients revealed active oxylipins, lysophospholipids, fatty acids, and endocannabinoids alterations.

Several oxylipins are identified as diagnostic biomarkers for OCP.
Deep venous thrombosis after Achilles tendon rupture is associated with poor patient-reported outcome
Authors: Svedman Simon , Edman Gunnar , Ackermann Paul W.
Published: April 2020

Purpose

The aim of this study was to investigate whether patient subjective and functional outcomes after Achilles tendon rupture (ATR) are related to deep venous thrombosis (DVT) during leg immobilization.

Methods

A cohort study with prospectively collected randomized data was conducted between 2010 and 2017. Two-hundred and fifty-one Patients with an Achilles tendon rupture (mean age = 41 ± 8), treated with uniform surgical techniques, were retrospectively analyzed. DVT incidence at 2 and 6 weeks was assessed using compression duplex ultrasound. At 12 months patient-reported outcomes were assessed using the Achilles tendon Total Rupture Score (ATRS), Foot- and Ankle Outcome Score (FAOS), Physical Activity Scale (PAS) and functional outcome with the calf-muscle endurance test. ANOVA analyses were used and adjusted for assumed confounding factors (patient age, sex, BMI and rehabilitation).

Results

The total DVT incidence was 122 out of 251 (49%). Patients suffering a DVT exhibited significantly lower ATRS at 1 year compared to patients without DVT (mean 76 vs 83, 95% CI 71–79 vs 80–87; p < 0.01). Sixty-seven percent (95% CI 57–77%) of the patients devoid of DVT reported a good outcome (ATRS > 80) compared to 51% (95% CI 41–61%) of the patients sustaining a DVT (p < 0.05). Quality of life displayed significantly better outcome in the non-DVT versus DVT patients (mean = 75 (95% CI 71–79) vs. mean = 68 (95% CI 64–72); p < 0.05). A significant difference in total concentric work was observed between non-DVT and DVT patients (median = 1.9 kJ (IQR = 0.9 kJ) vs. median = 1.6 kJ (IQR = 1.0 kJ); p < 0.01).

Conclusion

Sustaining a DVT during leg immobilization significantly impairs patient-reported outcome at 1 year after surgical repair of ATR.

Level of evidence

III.
A novel three-in-one silicone model for basic microsurgery training
Authors: Alser Osaid , Youssef Gehad , Myers Simon , Ghanem Ali M.
Published: April 2020

Background

Microsurgery simulation is an important aspect of surgical training. Animal models have been widely used in simulation training, but they have some limitations including ethical restrictions, cost and availability. This has led to the use of synthetic models that can reduce reliance on animals in line with the 3R (refinement, reduction and replacement) principles. The aim of this paper was to evaluate the face validity of Surgitate™ three-in-one (artery, vein and nerve) silicone model.

Methods

Fourteen candidates performed one end-to-end anastomosis on artery, vein and nerve. The face validity of the vessel was assessed via questionnaires detailing their previous microsurgical experience and their feedback of using this model using the Likert scale. Data management and analysis were performed using IBM SPSS software (25.0).

Results

Participants tended to value this model in the earlier stages of microsurgical training particularly in the acquisition of basic microsurgical skills. It could be particularly useful in enhancing suturing skills as a replacement or reduction in the use of chicken models. The model has some drawbacks preluding its utilization into more advanced stages of surgical training. Further studies are needed to validate the model using more objective measures.

Conclusion

We present a novel synthetic model that can be potentially introduced to early stages of microsurgery training. The model would be ideal to meet the 3R principles of the use of animal models and as an alternative to the commonly used synthetic models.

Level of evidence: Not ratable.
Epstein–Barr virus (EBV) and polyomaviruses are detectable in oropharyngeal cancer and EBV may have prognostic impact
Authors: Carpén Timo , Syrjänen Stina , Jouhi Lauri , Randen-Brady Reija , Haglund Caj , Mäkitie Antti , Mattila Petri S. , Hagström Jaana
Published: April 2020

Background

The etiological role of human papillomavirus (HPV) in oropharyngeal squamous cell carcinoma (OPSCC) is confirmed. However, the role of other oncoviruses in OPSCC is unknown.

Materials and methods

A total of 158 consecutive OPSCC patients treated with curative intent were included. DNA extracted from tumor sections was used to detect Epstein–Barr virus (EBV), HPV, and the following polyomaviruses: John Cunningham virus (JCV), Simian virus 40 (SV40), and BK virus (BKV) with PCR. In addition, p16 expression was studied by immunohistochemistry, and EBV-encoded small RNA (EBER) transcripts were localized by in situ hybridization. The effect of viral status on overall survival (OS) and disease-free survival (DFS) was analyzed.

Results

A total of 94/158 samples (59.5%) were HPV-positive, 29.1% contained BKV DNA, 20.3% EBV DNA, 13.9% JCV DNA, and 0.6% SV40 DNA. EBER was expressed only in stromal lymphocytes adjacent to the tumor and correlated with HPV positivity (p = 0.026). p16 expression associated only with HPV. None of the three polyomaviruses had an impact on survival. Patients with EBER-positive but HPV-negative OPSCC had significantly poorer OS and DFS than those with HPV-positive OPSCC and slightly worse prognosis compared with the patients with EBER-negative and HPV-negative OPSCC.

Conclusion

Polyomaviruses are detectable in OPSCC but seem to have no impact on survival, whereas HPV was the strongest viral prognostic factor. EBER expression, as a sign of latent EBV infection, may have prognostic impact among patients with HPV-negative OPSCC. EBER analysis may identify a new subgroup of OPSCCs unrelated to HPV.
Intravenous 5-fluoro-2′-deoxycytidine administered with tetrahydrouridine increases the proportion of p16-expressing circulating tumor cells in patients with advanced solid tumors
Authors: Coyne Geraldine O.’Sullivan , Wang Lihua , Zlott Jennifer , Juwara Lamin , Covey Joseph M. , Beumer Jan H. , Cristea Mihaela C. , Newman Edward M. , Koehler Stephen , Nieva Jorge J. , Garcia Agustin A. , Gandara David R. , Miller Brandon , Khin Sonny , Miller Sarah B. , Steinberg Seth M. , Rubinstein Larry , Parchment Ralph E. , Kinders Robert J. , Piekarz Richard L. , Kummar Shivaani , Chen Alice P. , Doroshow James H.
Published: April 2020

Purpose

Following promising responses to the DNA methyltransferase (DNMT) inhibitor 5-fluoro-2′-deoxycytidine (FdCyd) combined with tetrahydrouridine (THU) in phase 1 testing, we initiated a non-randomized phase 2 study to assess response to this combination in patients with advanced solid tumor types for which tumor suppressor gene methylation is potentially prognostic. To obtain pharmacodynamic evidence for DNMT inhibition by FdCyd, we developed a novel method for detecting expression of tumor suppressor protein p16/INK4A in circulating tumor cells (CTCs).

Methods

Patients in histology-specific strata (breast, head and neck [H&N], or non-small cell lung cancers [NSCLC] or urothelial transitional cell carcinoma) were administered FdCyd (100 mg/m2) and THU (350 mg/m2) intravenously 5 days/week for 2 weeks, in 28-day cycles, and progression-free survival (PFS) rate and objective response rate (ORR) were evaluated. Blood specimens were collected for CTC analysis.

Results

Ninety-three eligible patients were enrolled (29 breast, 21 H&N, 25 NSCLC, and 18 urothelial). There were three partial responses. All strata were terminated early due to insufficient responses (H&N, NSCLC) or slow accrual (breast, urothelial). However, the preliminary 4-month PFS rate (42%) in the urothelial stratum exceeded the predefined goal—though the ORR (5.6%) did not. An increase in the proportion of p16-expressing cytokeratin-positive CTCs was detected in 69% of patients evaluable for clinical and CTC response, but was not significantly associated with clinical response.

Conclusion

Further study of FdCyd + THU is potentially warranted in urothelial carcinoma but not NSCLC or breast or H&N cancer. Increase in the proportion of p16-expressing cytokeratin-positive CTCs is a pharmacodynamic marker of FdCyd target engagement.
The effect of time between procedures upon the proficiency gain period for minimally invasive esophagectomy
Authors: Markar Sheraz R. , Ni Melody , Mackenzie Hugh , Penna Marta , Faiz Omar , Hanna George B.
Published: April 2020

Background

Complex surgical procedures including minimally invasive esophagectomy (MIE) are commonly associated with a period of proficiency gain. We aim to study the effect of reduced procedural interval upon the number of cases required to gain proficiency and adverse patient outcomes during this period from MIE.

Methods

All adult patients undergoing MIE for esophageal cancer in England from 2002 to 2012 were identified from Hospital Episode Statistics database. Outcomes evaluated included conversion rate from MIE to open esophagectomy, 30-day re-intervention, 30-day and 90-day mortality. Regression models investigated relationships between procedural interval and the number of cases and clinical outcomes during proficiency gain period.

Results

The MIE dataset comprised of 1696 patents in total, with procedures carried out by 148 surgeons. Thresholds for procedural interval extracted from change-point modeling were found to be 60 days for conversion, 80 days for 30-day re-intervention, 80 days for 30-day mortality and 110 days for 90-day mortality. Procedural interval of MIEs did not influence the number of cases required for proficiency gain. However, reduced MIE procedural interval was associated with significant reductions in conversions (0.16 vs. 0.07; P < 0.001), re-interventions (0.15 vs. 0.09; P < 0.01), 30-day (0.12 vs. 0.05; P < 0.01) and 90-day (0.14 vs. 0.06; P < 0.01) mortality during the period of proficiency gain.

Conclusions

This national study has demonstrated that the introduction of MIE is associated with a period of proficiency gain and adverse patient outcomes. The absolute effect of this period of proficiency gain upon patient morbidity and mortality may be reduced by reduced procedural interval of MIE practice within specialized esophageal cancer centers.
Unlocking the PACS DICOM Domain for its Use in Clinical Research Data Warehouses
Authors: Kaspar Mathias , Liman Leon , Ertl Maximilian , Fette Georg , Seidlmayer Lea Katharina , Schreiber Laura , Puppe Frank , Störk Stefan
Published: April 2020

Clinical Data Warehouses (DWHs) are used to provide researchers with simplified access to pseudonymized and homogenized clinical routine data from multiple primary systems. Experience with the integration of imaging and metadata from picture archiving and communication systems (PACS), however, is rare. Our goal was therefore to analyze the viability of integrating a production PACS with a research DWH to enable DWH queries combining clinical and medical imaging metadata and to enable the DWH to display and download images ad hoc. We developed an application interface that enables to query the production PACS of a large hospital from a clinical research DWH containing pseudonymized data. We evaluated the performance of bulk extracting metadata from the PACS to the DWH and the performance of retrieving images ad hoc from the PACS for display and download within the DWH. We integrated the system into the query interface of our DWH and used it successfully in four use cases. The bulk extraction of imaging metadata required a median (quartiles) time of 0.09 (0.03–2.25) to 12.52 (4.11–37.30) seconds for a median (quartiles) number of 10 (3–29) to 103 (8–693) images per patient, depending on the extraction approach. The ad hoc image retrieval from the PACS required a median (quartiles) of 2.57 (2.57–2.79) seconds per image for the download, but 5.55 (4.91–6.06) seconds to display the first and 40.77 (38.60–41.63) seconds to display all images using the pure web-based viewer. A full integration of a production PACS with a research DWH is viable and enables various use cases in research. While the extraction of basic metadata from all images can be done with reasonable effort, the extraction of all metadata seems to be more appropriate for subgroups.
A comparison of penalty shootout designs in soccer
Authors: Csató László
Published: April 2020

Penalty shootout in soccer is recognized to be unfair because the team kicking first in all rounds enjoys a significant advantage. The so-called Catch-Up Rule has been suggested recently to solve this problem but is shown here not to be fairer than the simpler deterministic Alternating (ABBA) Rule that has already been tried. We introduce the Adjusted Catch-Up Rule by guaranteeing the first penalty of the possible sudden death stage to the team disadvantaged in the first round. It outperforms the Catch-Up and Alternating Rules, while remains straightforward to implement. A general measure of complexity for penalty shootout mechanisms is also provided as the minimal number of binary questions required to decide the first-mover in a given round without knowing the history of the penalty shootout. This quantification permits a two-dimensional evaluation of any mechanism proposed in the future.
Perspectives on Bioengineering Clinical Immersion: History, Innovation, and Impact
Authors: Kotche Miiri , Felder Anthony E. , Wilkens Kimberlee , Stirling Susan
Published: April 2020

Opportunities to provide clinical immersion experiences to bioengineering undergraduate students have expanded over the last several years. These programs allow students to observe the clinical environment in order to better understand workflow processes, the context in which medical equipment is used, and identify unmet needs firsthand. While each program focuses on identifying unmet needs, these experiences vary in content and implementation. Here we discuss features of clinical immersion programs, share details of our program after six years, and present data regarding post-graduation employment of our participants. Students who participated in the University of Illinois at Chicago Clinical Immersion Program are not more likely to pursue careers in industry as compared to non-participants, nor do they demonstrate an ability to find a job more quickly than non-participants. However, participants who did enter into industry self-reported that the program was impactful to both their career interests and ability to find their first employment position.
Root xylem in three woody angiosperm species is not more vulnerable to embolism than stem xylem
Authors: Wu Min , Zhang Ya , Oya Thais , Marcati Carmen Regina , Pereira Luciano , Jansen Steven
Published: April 2020

Aims

Since plants are compartmentalised organisms, failure of their hydraulic transport system could differ between organs. We test here whether xylem tissue of stems and roots differ in their drought-induced embolism resistance, and whether intact roots are equally resistant to embolism than root segments.

Methods

Embolism resistance of stem and root xylem was measured based on the pneumatic technique for Acer campestre, A. pseudoplatanus and Corylus avellana, comparing also intact roots and root segments of C. avellana. Moreover, we compared anatomical features such as interconduit pit membrane between roots and stems.

Results

We found a higher embolism resistance for roots than stems, although a significant difference was only found for A. pseudoplatanus. Interconduit pit membrane thickness was similar for both organs of the two Acer species, but pit membranes were thicker in roots than stems of C. avellana. Also, embolism resistance of an intact root network was similar to thick root segments for C. avellana.

Conclusion

Our observations show that root xylem is not more vulnerable to embolism than stem xylem, although more species need to be studied to test if this finding can be generalised. We also demonstrated that the pneumatic method can be applied to non-terminal plant samples.
Lying, Misleading, and the Argument from Cultural Slopes
Authors: Herzog Lisa
Published: April 2020

This paper discusses a novel kind of argument for assessing the moral significance of acts of lying and misleading. It is based on considerations about valuable social norms that might be eroded by these actions, because these actions function as signals. Given that social norms can play an important role in supporting morality, individuals have a responsibility to preserve such norms and to prevent ‘cultural slopes’ that erode them. Depending on whether there are norms against lying, misleading, or both, and how likely it is that they might be eroded, these actions can thus have different moral significance. In cases in which the rule ‘do not lie’, as a relatively simple rule, functions as a ‘focal point’, acts of misleading are often morally preferable. In other words, in such cases the possibility of ‘cultural slopes’ can ground a context-dependent slippery slope argument for a moral difference between lying and misleading.
ARoCuS Web application promotes standardized treatment and documentation of rotator cuff tears
Authors: Walter S. G. , Cucchi D. , Thomas W. , Friedrich M. J. , Jansen T.
Published: April 2020

Purpose

To program a Web application for simplified calculation of the Advanced Rotator Cuff tear Score (ARoCuS), which is a 5-part, 18-item treatment-oriented intraoperative scoring system for intraoperative evaluation of rotator cuff tears.

Methods

ARoCuS characteristics (torn tendon, tear size, tissue quality and tear pattern) were assessed intraoperatively on 40 consecutive patients with rotator cuff tears for calculation of defect category ΔV. Video recordings were used to re-calculate the ARoCuS after surgery and to assess inter-observer reliability.

Results

The Web application “ARoCuS App” was built using Angular and transformed to a native iOS application. The intraoperative use of the app proved to be simple and intuitive. There were inter-/intra-observer differences neither in ARoCuS defect categories ΔV nor in ARoCuS characteristics (p > 0.05).

Conclusion

The ARoCuS app is a supportive tool for integration of standardized treatment procedures and documentation of rotator cuff tears in clinical routine.