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1.
Arthroscopy ; 40(2): 438-445, 2024 02.
Article in English | MEDLINE | ID: mdl-37479150

ABSTRACT

PURPOSE: To compare clinical and patient-reported outcome measures (PROMs) in patients with recurrent patellar dislocation after medial patellofemoral ligament (MPFL) reconstruction using either a gracilis tendon (GT) or quadriceps tendon autograft (QT). METHODS: All MPFL reconstruction performed between 2017 and 2019 were reviewed retrospectively. Only patients with isolated MPFL reconstruction, without any major patellofemoral risk factors and a minimum follow-up of 24 months, were included in the study. Patients were matched with respect to sex, age, and body mass index. All patients were evaluated clinically and using PROMs. RESULTS: A total of 64 patients with an average follow up of 28.7 ± 7.5 months were included in this study. The mean Kujala score (GT: 84.8 ± 12.9, QT: 88.9 ± 10.1), Lysholm score (GT: 89.4 ± 10.2, QT: 88.4 ± 5.0), and visual analog scale score for pain (GT: 1.9 ± 1.8, QT: 1.1 ± 1.3) did not significantly differ between both groups. Tegner activity level was significantly greater (P = .027) in the QT group (5.5 ± 1.9) compared with the GT group (4.6 ± 1.8), but within the minimal clinically important differences. Occasional patellar instability events, but no recurrent dislocation, were reported in 12.5% in the GT group and 6.3% in the QT group (P = .39). Of all patients, 90.6% in the QT and 68.8% in the HT group exceeded the PASS for the Kujala score (P = .06). Significantly more patients (59.4%) treated with GT reported donor-site morbidity in the form of sensitivity deficit at the lower leg compared with those treated with QT (3.1%, P = .001). CONCLUSIONS: GT and QT MPFL reconstruction have comparable PROMs and patellar redislocation rates 2 years' postoperatively. Significantly more patients treated with GT reported lower-leg sensitivity deficit compared with those treated with QT. LEVEL OF EVIDENCE: Level III, retrospective case-control study.


Subject(s)
Joint Instability , Patellar Dislocation , Patellofemoral Joint , Humans , Retrospective Studies , Autografts , Joint Instability/surgery , Case-Control Studies , Patellofemoral Joint/surgery , Tendons/transplantation , Ligaments, Articular/surgery , Patient Reported Outcome Measures , Patellar Dislocation/surgery
2.
Zentralbl Chir ; 148(3): 284-292, 2023 Jun.
Article in German | MEDLINE | ID: mdl-36167311

ABSTRACT

In recent years, the use of mechanical support for patients with cardiac or circulatory failure has continuously increased, leading to 3,000 ECLS/ECMO (extracorporeal life support/extracorporeal membrane oxygenation) implantations annually in Germany. Due to the lack of guidelines, there is an urgent need for evidence-based recommendations addressing the central aspects of ECLS/ECMO therapy. In July 2015, the generation of a guideline level S3 according to the standards of the Association of the Scientific Medical Societies in Germany (AWMF) was announced by the German Society for Thoracic and Cardiovascular Surgery (GSTCVS). In a well-structured consensus process, involving experts from Germany, Austria and Switzerland, delegated by 16 scientific societies and the patients' representation, the guideline "Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure" was created under guidance of the GSTCVS, and published in February 2021. The guideline focuses on clinical aspects of initiation, continuation, weaning and aftercare, herein also addressing structural and economic issues. This article presents an overview on the methodology as well as the final recommendations.


Subject(s)
Extracorporeal Membrane Oxygenation , Shock , Humans , Societies, Scientific , Extracorporeal Circulation , Societies, Medical , Germany
3.
iScience ; 25(12): 105551, 2022 Dec 22.
Article in English | MEDLINE | ID: mdl-36458255

ABSTRACT

Pathways to eradicate global hunger while bending the curve of biodiversity loss unanimously suggest changing to less energy-rich diets, closing yield gaps through agroecological principles, adopting modern breeding technologies to foster stress resilience and yields, as well as minimizing harvest losses and food waste. Against the background of a brief history of global agriculture, we review the available evidence on how the global food system might look given a global temperature increase by 3°. We show that a moderate gain in the area suitable for agriculture is confronted with substantial yield losses through strains on crop physiology, multitrophic interactions, and more frequent extreme events. Self-amplifying feedback are unresolved and might lead to further losses. In light of these uncertainties, we see that complexity is underestimated and more systemic research is needed. Efficiency gains in agriculture, albeit indispensable, will not be enough to achieve food security under severe climate change.

4.
J Asthma Allergy ; 15: 1217-1226, 2022.
Article in English | MEDLINE | ID: mdl-36071746

ABSTRACT

Purpose: Ailanthus altissima is one of the world's most invasive species with a globally problematic spread. Pollen is dispersed locally and partially airborne. We aimed at investigating if (i) A. altissima pollen can be detected in relevant quantity in the air and if (ii) sensitization to A. altissima can be detected in patients with seasonal exacerbation of atopic diseases. Patients and Methods: We recorded distribution of A. altissima in Leipzig, Germany. In 2019 and 2020, pollen was collected with a Hirst-type pollen trap placed on the roof of the University Hospital. Specific IgE investigations were performed in children and adults with history of atopic diseases with deterioration between May and July. We analysed specific IgE for A. altissima, Alternaria sp., birch, grasses, profilins, polcalcins and crossreacting carbohydrates. Results: We found abundant growth of A. altissima and pollen was detected from early June to mid-July with a maximum pollen concentration of 31 pollen/m3. Out of 138 patients (63 female, 69 children/adolescents), 95 (69%) had seasonal allergic rhinitis, 84 (61%) asthma, and 43 (31%) atopic dermatitis. Sensitization to A. altissima was shown in 59 (42%). There were no significant differences between age groups. In 59% of patients sensitized (35/59), there was no sensitization to possibly cross-reacting structures. Conclusion: Sensitization to A. altissima pollen could be detected in 42% of our patients with atopic diseases, suggesting allergenic potential of this neophyte. In the context of further spread with climate change, eradication strategies and population-based sensitization studies are needed.

5.
Proc Natl Acad Sci U S A ; 119(40): e2208717119, 2022 Oct 04.
Article in English | MEDLINE | ID: mdl-36161890

ABSTRACT

Ice polymorphs show extraordinary structural diversity depending on pressure and temperature. The behavior of hydrogen-bond disorder not only is a key ingredient for their structural diversity but also controls their physical properties. However, it has been a challenge to determine the details of the disordered structure in ice polymorphs under pressure, because of the limited observable reciprocal space and inaccuracies related to high-pressure techniques. Here, we present an elucidation of the disordered structure of ice VII, the dominant high-pressure form of water, at 2.2 GPa and 298 K, from both single-crystal and powder neutron-diffraction techniques. We reveal the three-dimensional atomic distributions from the maximum entropy method and unexpectedly find a ring-like distribution of hydrogen in contrast to the commonly accepted discrete sites. In addition, total scattering analysis at 274 K clarified the difference in the intermolecular structure from ice VIII, the ordered counterpart of ice VII, despite an identical molecular geometry. Our complementary structure analyses robustly demonstrate the unique disordered structure of ice VII. Furthermore, these findings are related to proton dynamics, which drastically vary with pressure, and will contribute to an understanding of the structural origin of anomalous physical properties of ice VII under pressures.

6.
J Phys Chem Lett ; 13(30): 6919-6926, 2022 Aug 04.
Article in English | MEDLINE | ID: mdl-35867700

ABSTRACT

While HgTe nanocrystals (NCs) in the mid-infrared region have reached a high level of maturity, their far-infrared counterparts remain far less studied, raising the need for an in-depth investigation of the material before efficient device integration can be considered. Here, we explore the effect of temperature and pressure on the structural, spectroscopic, and transport properties of HgTe NCs displaying an intraband absorption at 10 THz. The temperature leads to a very weak modulation of the spectrum as opposed to what was observed for strongly confined HgTe NCs. HgTe NC films present ambipolar conduction with a clear prevalence of electron conduction as confirmed by transistor and thermoelectric measurements. Under the application of pressure, the material undergoes phase transitions from the zinc blende to cinnabar phase and later to the rock salt phase which we reveal using joint X-ray diffraction and infrared spectroscopy measurements. We discuss how the pressure existence domain of each phase is affected by the particle size.

7.
ESC Heart Fail ; 9(1): 506-518, 2022 02.
Article in English | MEDLINE | ID: mdl-34811959

ABSTRACT

Aims Worldwide applications of extracorporeal circulation for mechanical support in cardiac and circulatory failure, which are referred to as extracorporeal life support (ECLS) or veno-arterial extracorporeal membrane oxygenation (va-ECMO), have dramatically increased over the past decade. In spite of the expanding use and the immense medical as well as socio-economic impact of this therapeutic approach, there has been a lack of interdisciplinary recommendations considering the best available evidence for ECLS treatment. Methods and Results In a multiprofessional, interdisciplinary scientific effort of all scientific societies involved in the treatment of patients with acute cardiac and circulatory failure, the first evidence- and expert consensus-based guideline (level S3) on ECLS/ECMO therapy was developed in a structured approach under regulations of the AWMF (Association of the Scientific Medical Societies in Germany) and under use of GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. This article presents all recommendations created by the expert panel, addressing a multitude of aspects for ECLS initiation, continuation, weaning and aftercare as well as structural and personnel requirements. Conclusions This first evidence- and expert consensus-based guideline (level S3) on ECLS/ECMO therapy should be used to apply the best available care nationwide. Beyond clinical practice advice, remaining important research aspects for future scientific efforts are formulated.


Subject(s)
Extracorporeal Membrane Oxygenation , Shock , Extracorporeal Circulation , Extracorporeal Membrane Oxygenation/methods , Germany , Humans , Practice Guidelines as Topic , Shock/etiology
8.
J Chem Phys ; 155(19): 194506, 2021 Nov 21.
Article in English | MEDLINE | ID: mdl-34800945

ABSTRACT

The structure of a concentrated solution of NaCl in D2O was investigated by in situ high-pressure neutron diffraction with chlorine isotope substitution to give site-specific information on the coordination environment of the chloride ion. A broad range of densities was explored by first increasing the temperature from 323 to 423 K at 0.1 kbar and then increasing the pressure from 0.1 to 33.8 kbar at 423 K, thus mapping a cyclic variation in the static dielectric constant of the pure solvent. The experimental work was complemented by molecular dynamics simulations using the TIP4P/2005 model for water, which were validated against the measured equation of state and diffraction results. Pressure-induced anion ordering is observed, which is accompanied by a dramatic increase in the Cl-O and O-O coordination numbers. With the aid of bond-distance resolved bond-angle maps, it is found that the increased coordination numbers do not originate from a sizable alteration to the number of either Cl⋯D-O or O⋯D-O hydrogen bonds but from the appearance of non-hydrogen-bonded configurations. Increased pressure leads to a marked decrease in the self-diffusion coefficients but has only a moderate effect on the ion-water residence times. Contact ion pairs are observed under all conditions, mostly in the form of charge-neutral NaCl0 units, and coexist with solvent-separated Na+-Na+ and Cl--Cl- ion pairs. The exchange of water molecules with Na+ adopts a concerted mechanism under ambient conditions but becomes non-concerted as the state conditions are changed. Our findings are important for understanding the role of extreme conditions in geochemical processes.

9.
Ecol Evol ; 11(21): 15174-15190, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34765169

ABSTRACT

Across the globe, ecological communities are confronted with multiple global environmental change drivers, and they are responding in complex ways ranging from behavioral, physiological, and morphological changes within populations to changes in community composition and food web structure with consequences for ecosystem functioning. A better understanding of global change-induced alterations of multitrophic biodiversity and the ecosystem-level responses in terrestrial ecosystems requires holistic and integrative experimental approaches to manipulate and study complex communities and processes above and below the ground. We argue that mesocosm experiments fill a critical gap in this context, especially when based on ecological theory and coupled with microcosm experiments, field experiments, and observational studies of macroecological patterns. We describe the design and specifications of a novel terrestrial mesocosm facility, the iDiv Ecotron. It was developed to allow the setup and maintenance of complex communities and the manipulation of several abiotic factors in a near-natural way, while simultaneously measuring multiple ecosystem functions. To demonstrate the capabilities of the facility, we provide a case study. This study shows that changes in aboveground multitrophic interactions caused by decreased predator densities can have cascading effects on the composition of belowground communities. The iDiv Ecotrons technical features, which allow for the assembly of an endless spectrum of ecosystem components, create the opportunity for collaboration among researchers with an equally broad spectrum of expertise. In the last part, we outline some of such components that will be implemented in future ecological experiments to be realized in the iDiv Ecotron.

11.
Anaesthesist ; 70(11): 942-950, 2021 11.
Article in German | MEDLINE | ID: mdl-34665266

ABSTRACT

In Germany, a remarkable increase regarding the usage of extracorporeal membrane oxygenation (ECMO) and extracorporeal life support (ECLS) systems has been observed in recent years with approximately 3000 ECLS/ECMO implantations annually since 2015. Despite the widespread use of ECLS/ECMO, evidence-based recommendations or guidelines are still lacking regarding indications, contraindications, limitations and management of ECMO/ECLS patients. Therefore in 2015, the German Society of Thoracic and Cardiovascular Surgery (GSTCVS) registered the multidisciplinary S3 guideline "Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure" to develop evidence-based recommendations for ECMO/ECLS systems according to the requirements of the Association of the Scientific Medical Societies in Germany (AWMF). Although the clinical application of ECMO/ECLS represents the main focus, the presented guideline also addresses structural and economic issues. Experts from 17 German, Austrian and Swiss scientific societies and a patients' organization, guided by the GSTCVS, completed the project in February 2021. In this report, we present a summary of the methodological concept and tables displaying the recommendations for each chapter of the guideline.


Subject(s)
Extracorporeal Membrane Oxygenation , Shock , Extracorporeal Circulation , Germany , Humans , Life Support Systems
12.
Med Klin Intensivmed Notfmed ; 116(8): 678-686, 2021 Nov.
Article in German | MEDLINE | ID: mdl-34665281

ABSTRACT

In Germany, a remarkable increase regarding the usage of extracorporeal membrane oxygenation (ECMO) and extracorporeal life support (ECLS) systems has been observed in recent years with approximately 3000 ECLS/ECMO implantations annually since 2015. Despite the widespread use of ECLS/ECMO, evidence-based recommendations or guidelines are still lacking regarding indications, contraindications, limitations and management of ECMO/ECLS patients. Therefore in 2015, the German Society of Thoracic and Cardiovascular Surgery (GSTCVS) registered the multidisciplinary S3 guideline "Use of extracorporeal circulation (ECLS/ECMO) for cardiac and circulatory failure" to develop evidence-based recommendations for ECMO/ECLS systems according to the requirements of the Association of the Scientific Medical Societies in Germany (AWMF). Although the clinical application of ECMO/ECLS represents the main focus, the presented guideline also addresses structural and economic issues. Experts from 17 German, Austrian and Swiss scientific societies and a patients' organization, guided by the GSTCVS, completed the project in February 2021. In this report, we present a summary of the methodological concept and tables displaying the recommendations for each chapter of the guideline.


Subject(s)
Extracorporeal Membrane Oxygenation , Shock , Extracorporeal Circulation , Germany , Humans , Life Support Systems
13.
Neurol Res Pract ; 3(1): 50, 2021 Sep 20.
Article in English | MEDLINE | ID: mdl-34538282

ABSTRACT

BACKGROUND: Thrombus histology has become a potential diagnostic tool for the etiology assessment of patients with ischemic stroke caused by embolic proximal vessel occlusion. We validated a classification rule that differentiates between cardiac and arteriosclerotic emboli in individual stroke patients. We aim to describe in detail the development of this classification rule and disclose its reliability. METHODS: The classification rule is based on the hypothesis that cardiac emboli arise out of separation thrombi and arteriosclerotic emboli result from agglutinative thrombi. 125 emboli recovered by thrombectomy from stroke patients and 11 thrombi serving as references for cardiac (n = 5) and arteriosclerotic emboli (n = 6) were Hematoxylin and eosin, Elastica-van Gieson and CD61 stained and rated independently by two histopathologists blinded to the presumed etiology by several pre-defined criteria. Intra- and interobserver reliabilities of all criteria were determined. Out of the different criteria, three criteria with the most satisfactory reliability values were selected to compose the classification rule that was finally adjusted to the reference thrombi. Reliabilities of the classification rule were calculated by using the emboli of stroke patients. RESULTS: The classification rule reached intraobserver reliabilities for the two raters of 92.9% and 68.2%, respectively. Interobserver reliability was 69.9%. CONCLUSIONS: A new classification rule for emboli obtained from thrombectomy was established. Within the limitations of histological investigations, it is reliable and able to distinguish between cardioembolic and arteriosclerotic emboli.

15.
J Chem Phys ; 155(2): 024506, 2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34266244

ABSTRACT

New data on the variation of the thermal expansion of ice Ih with temperature at ambient pressure together with new evaluations of the bulk modulus and earlier data for the heat capacity provide the basis for a coherent thermodynamic modeling of the main thermophysical properties of ice Ih over its whole range of stability. The quasi-harmonic approximation with one Debye term and seven Einstein terms, together with explicit anharmonicity, represents the dominant contribution next to minor "anomalies" from hydrogen ordering and lattice defects. The model accurately fits the main features of all experimental data and provides a basis for the comparison with earlier determinations of the phonon density of states and the Grüneisen parameters.

16.
Nat Commun ; 12(1): 1958, 2021 Mar 30.
Article in English | MEDLINE | ID: mdl-33785748

ABSTRACT

Methane, the principal component of natural gas, is an important energy source and raw material for chemical reactions. It also plays a significant role in planetary physics, being one of the major constituents of giant planets. Here, we report measurements of the molecular self-diffusion coefficient of dense supercritical CH4 reaching the freezing pressure. We find that the high-pressure behaviour of the self-diffusion coefficient measured by quasi-elastic neutron scattering at 300 K departs from that expected for a dense fluid of hard spheres and suggests a density-dependent molecular diameter. Breakdown of the Stokes-Einstein-Sutherland relation is observed and the experimental results suggest the existence of another scaling between self-diffusion coefficient D and shear viscosity η, in such a way that Dη/ρ=constant at constant temperature, with ρ the density. These findings underpin the lack of a simple model for dense fluids including the pressure dependence of their transport properties.

17.
Proc Natl Acad Sci U S A ; 117(12): 6356-6361, 2020 Mar 24.
Article in English | MEDLINE | ID: mdl-32161135

ABSTRACT

Above 2 GPa the phase diagram of water simplifies considerably and exhibits only two solid phases up to 60 GPa, ice VII and ice VIII. The two phases are related to each other by hydrogen ordering, with the oxygen sublattice being essentially the same. Here we present neutron diffraction data to 15 GPa which reveal that the rate of hydrogen ordering at the ice VII-VIII transition decreases strongly with pressure to reach timescales of minutes at 10 GPa. Surprisingly, the ordering process becomes more rapid again upon further compression. We show that such an unusual change in transition rate can be explained by a slowing down of the rotational dynamics of water molecules with a simultaneous increase of translational motion of hydrogen under pressure, as previously suspected. The observed cross-over in the hydrogen dynamics in ice is likely the origin of various hitherto unexplained anomalies of ice VII in the 10-15 GPa range reported by Raman spectroscopy, X-ray diffraction, and proton conductivity.

18.
Glob Ecol Biogeogr ; 29(2): 281-294, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32063745

ABSTRACT

AIM: Alien plant species can cause severe ecological and economic problems, and therefore attract a lot of research interest in biogeography and related fields. To identify potential future invasive species, we need to better understand the mechanisms underlying the abundances of invasive tree species in their new ranges, and whether these mechanisms differ between their native and alien ranges. Here, we test two hypotheses: that greater relative abundance is promoted by (a) functional difference from locally co-occurring trees, and (b) higher values than locally co-occurring trees for traits linked to competitive ability. LOCATION: Global. TIME PERIOD: Recent. MAJOR TAXA STUDIED: Trees. METHODS: We combined three global plant databases: sPlot vegetation-plot database, TRY plant trait database and Global Naturalized Alien Flora (GloNAF) database. We used a hierarchical Bayesian linear regression model to assess the factors associated with variation in local abundance, and how these relationships vary between native and alien ranges and depend on species' traits. RESULTS: In both ranges, species reach highest abundance if they are functionally similar to co-occurring species, yet are taller and have higher seed mass and wood density than co-occurring species. MAIN CONCLUSIONS: Our results suggest that light limitation leads to strong environmental and biotic filtering, and that it is advantageous to be taller and have denser wood. The striking similarities in abundance between native and alien ranges imply that information from tree species' native ranges can be used to predict in which habitats introduced species may become dominant.

19.
Proc Natl Acad Sci U S A ; 116(41): 20280-20285, 2019 10 08.
Article in English | MEDLINE | ID: mdl-31548383

ABSTRACT

Using X-ray emission spectroscopy, we find appreciable local magnetic moments until 30 GPa to 40 GPa in the high-pressure phase of iron; however, no magnetic order is detected with neutron powder diffraction down to 1.8 K, contrary to previous predictions. Our first-principles calculations reveal a "spin-smectic" state lower in energy than previous results. This state forms antiferromagnetic bilayers separated by null spin bilayers, which allows a complete relaxation of the inherent frustration of antiferromagnetism on a hexagonal close-packed lattice. The magnetic bilayers are likely orientationally disordered, owing to the soft interlayer excitations and the near-degeneracy with other smectic phases. This possible lack of long-range correlation agrees with the null results from neutron powder diffraction. An orientationally disordered, spin-smectic state resolves previously perceived contradictions in high-pressure iron and could be integral to explaining its puzzling superconductivity.

20.
J Environ Manage ; 250: 109479, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31499467

ABSTRACT

Distributed environmental research infrastructures are important to support assessments of the effects of global change on landscapes, ecosystems and society. These infrastructures need to provide continuity to address long-term change, yet be flexible enough to respond to rapid societal and technological developments that modify research priorities. We used a horizon scanning exercise to identify and prioritize emerging research questions for the future development of ecosystem and socio-ecological research infrastructures in Europe. Twenty research questions covered topics related to (i) ecosystem structures and processes, (ii) the impacts of anthropogenic drivers on ecosystems, (iii) ecosystem services and socio-ecological systems and (iv), methods and research infrastructures. Several key priorities for the development of research infrastructures emerged. Addressing complex environmental issues requires the adoption of a whole-system approach, achieved through integration of biotic, abiotic and socio-economic measurements. Interoperability among different research infrastructures needs to be improved by developing standard measurements, harmonizing methods, and establishing capacities and tools for data integration, processing, storage and analysis. Future research infrastructures should support a range of methodological approaches including observation, experiments and modelling. They should also have flexibility to respond to new requirements, for example by adjusting the spatio-temporal design of measurements. When new methods are introduced, compatibility with important long-term data series must be ensured. Finally, indicators, tools, and transdisciplinary approaches to identify, quantify and value ecosystem services across spatial scales and domains need to be advanced.


Subject(s)
Ecology , Ecosystem , Europe
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