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A novel approach toward electromagnetic launch is presented. In general, a railgun-type launcher is characterized by its unique ability to accelerate macroscopic masses (up to several kilograms) to speeds of 2 km/s. This is mostly done using capacitor banks in crowbar configuration resulting quasi-dc current profiles. The innovation of the work presented here is the use of multiphase current for driving railgun-type launchers. To this end, both the accelerator and the energy supply have to be redesigned. The use of ${n}$ multiple phases means that the accelerator has to have in principle n pairs of rails, meaning that also the armature differs strongly from classical solutions. One purpose of the project was to connect the launcher to the local power grid. Therefore, a corresponding generator had to be developed. A novel design characterized by the use of augmenting field coils is presented in that regard. In order to achieve high payload velocities with such a multiphase setup, several stages or modules are required. A system consisting of two modules is introduced here and experimental results are shown. The particular design using field coils allows for a mode of operation where a part of the current is fed from a subsequent module back to the muzzle of the preceding one leading to an increase of the propulsive force.

Zusammenfassung: Die vorliegende Kasuistik beschreibt eine Harnleiterkolik durch interventionsradiologisch eingebrachtes Embolisationsmaterial. Koliken durch Fremdkörper im Harntrakt sind sehr selten und überwiegend iatrogen bedingt. Aufgrund der breit etablierten Anwendung interventionsradiologischer Methoden zur Beherrschung von Blutungskomplikationen nach endourologischen Eingriffen ist der dargestellte Fall von besonderem praktischem Interesse. Bei einer 80-jährigen Patientin mit einer langen Anamnese einer rezidivierenden Nephrolithiasis beidseits kam es im Rahmen einer PCNL rechts zu einer protrahierten transfusionspflichtigen Blutung. Die Blutungsquelle wurde mittels Coiling embolisiert. Rund 2 Jahre später wurde bei persistierenden Flankenschmerzen sowie Harnstauung rechts die Dislokation eines Coils in den rechten Ureterabgang diagnostiziert. Nach primärer Harnleiterschienung wurde der Fremdkörper im entzündungsfreien Intervall durch eine Ureterotomie entfernt.

The article focuses on the controversies and effectiveness of brain training programs, examining claims that these exercises enhance cognitive abilities and prevent decline. Topics include the marketing of brain training tools, the nun study suggesting mental activity's potential role in staving off cognitive decline, and critical considerations in evaluating the efficacy of brain training interventions.

Poly-ether-ether-ketone (PEEK) composites present outstanding physical and chemical properties, including radiation tolerance and compatibility with vacuum and additive manufacturing processing. Applications of PEEK range from biomedical to aerospace. Controlled 3-D nanostructuring arises as a powerful approach to generate new phenomena suitable for technological applications. In this sense, we target to synthesize robust and shapeable magnetic nanocomposites (NCs) for sensing and electromagnetic shielding applications. For this aim, we synthesized and characterized Permalloy (Py, Ni80Fe20) nanostructured surfaces on PEEK/TiO2. These NCs were synthesized by scalable and high throughput compatible fabrication approaches: anodization (TiO2 nanotubes) and hot embossing (thermal nanoimprint). The resulting NCs are shapeable, stable below 300 °C, and vacuum compatible. Their surfaces compose TiO2 nanodomes filled by PEEK. Py layers (15 nm) were sputtered on NC and flat PEEK films. The characterization included SEM, AFM, ISO-2409 Adhesion Tests, hysteresis loops, and first-order reversal curves (FORCs). The results revealed that both types of films keep stable characteristics after bending cycles, and noticeable modifications of the magnetic global response and local interactions generated due to the 3-D nanostructure.

The effect of gaseous atmosphere during Laser Powder Bed Fusion (L-PBF) was analysed on an Inconel 625 alloy. The bead dimensions, the surface finish, the porosity rate and the resulting microstructure were analysed for three different gases (Argon, Nitrogen and Helium) in an industrial L-PBF machine, using rather high energy density promoting keyhole welding regime. No clear effect of gas nature on energy coupling was shown when considering fusion beads on L-PBF parts. However, this work shows that gas, and especially helium mostly modifies surface finish, due to a modification of heat dissipation at the interface between the built part and the powder bed. This effect is clearly beneficial for vertical builds but is balanced by a possible and detrimental reduction of surface tensions for inclined and overhanging surfaces. The data presented here indicates a moderate benefit of He and N2gases on porosity rates at high laser energy, but the as-built microstructures do not exhibit detectable differences, at the scale considered for the analyses (SEM + EBSD). Some physical aspects of the liquid/gas interface are discussed at the end of the paper to explain the observed results.

The round robin test investigated the reliability users can expect for AlSi10Mg additive manufactured specimens by laser powder bed fusion through examining powder quality, process parameter, microstructure defects, strength and fatigue. Besides for one outlier, expected static material properties could be found. Optical microstructure inspection was beneficial to determine true porosity and porosity types to explain the occurring scatter in properties. Fractographic analyses reveal that the fatigue crack propagation starts at the rough as-built surface for all specimens. Statistical analysis of the scatter in fatigue using statistical derived safety factors concludes that at a stress of 36.87 MPa the fatigue limit of 107cycles could be reached for all specimen with a survival probability of 99.999 %.

Wallach’s rule elucidates the phenomenon that racemic crystals are denser than their enantiopure form. The rule applies to most chiral molecular systems with the exception of some amino acids. However, it remains unclear whether Wallach’s rule applies to the special but important class of chiral systems where chirality is induced by the adsorption of prochiral molecules on substrates. In this work, we show that the exemplary system, Cobalt(II)-diphenylporphyrin (Co-DPP) on Cu (111), follows Wallach’s rule. Co-DPP assumes chiral isomers upon adsorption and shows a phase transition from an enantiopure linear chain structure to a racemic close-packed structure with increasing molecular density. Density functional theory (DFT) reveals that the chiral recognition, separation, and phase mixture of Co-DPP are due to the synergistic mechanism of substrate–molecule and molecule–molecule interactions.

À l'ère du changement climatique, les zones urbaines telles que Paris sont confrontées à des défis accrus en matière de santé publique, notamment lors des vagues de chaleur. Bien qu'une prise de conscience croissante existe, il existe un vide de recherche concernant les effets intersectionnels des vagues de chaleur, des variables environnementales et des facteurs démographiques dans des zones urbaines denses telles que Paris.

Obtaining a burning plasma is a critical step towards self-sustaining fusion energy1. A burning plasma is one in which the fusion reactions themselves are the primary source of heating in the plasma, which is necessary to sustain and propagate the burn, enabling high energy gain. After decades of fusion research, here we achieve a burning-plasma state in the laboratory. These experiments were conducted at the US National Ignition Facility, a laser facility delivering up to 1.9 megajoules of energy in pulses with peak powers up to 500 terawatts. We use the lasers to generate X-rays in a radiation cavity to indirectly drive a fuel-containing capsule via the X-ray ablation pressure, which results in the implosion process compressing and heating the fuel via mechanical work. The burning-plasma state was created using a strategy to increase the spatial scale of the capsule2,3through two different implosion concepts4–7. These experiments show fusion self-heating in excess of the mechanical work injected into the implosions, satisfying several burning-plasma metrics3,8. Additionally, we describe a subset of experiments that appear to have crossed the static self-heating boundary, where fusion heating surpasses the energy losses from radiation and conduction. These results provide an opportunity to study α-particle-dominated plasmas and burning-plasma physics in the laboratory.

Hintergrund: Die Ellenbogensteife stellt sowohl für den Operateur als auch für den postoperativen Nachsorger eine große Herausforderung dar. Hinsichtlich der sich anschließenden Rehabilitation und deren Inhalte besteht bis dato kein Konsens. Ziel: Das Ziel ist es, die wichtigsten Therapieinhalte nach Arthrolyse des Ellenbogens anhand einer umfassenden Literaturrecherche evidenzbasiert zu bewerten und mit Hilfe einer Umfrage unter ausgewiesenen DVSE-Ellenbogenexperten (D-A-CH Vereinigung für Schulter- und Ellenbogenchirurgie e. V.) einen möglichen bestehenden Konsens für oder gegen spezifische Therapieinhalte zu eruieren. Material und Methoden: Die Literatursuche erfolgte nach Leitlinien, den „health technology assessments“, systematischen Übersichtsarbeiten und klinischen Studien, die die postoperative Rehabilitation nach Arthrolyse des Ellenbogens untersuchten. Abgefragt wurden die Datenbanken des „Guidelines International Network“, diverse nationale Leitlinien, PubMed, das „Cochrane Central Register of Controlled Trials“, die „Cochrane Database of Systematic Reviews“ und die „Physiotherapy Evidence Database“, jeweils für den Zeitraum 01/1989 bis 12/2019. Im Rahmen einer Online-Umfrage wurden allen aktiven DVSE-Mitgliedern zu spezifischen Therapieinhalten der Rehabilitation nach Arthrolyse befragt. Ergebnisse: Im Zeitraum seit 1989 ließen sich aus 266 Artikeln 5 Reviews und 58 Originalarbeiten identifizieren, die als Grundlage zur Anfertigung einer evidenzbasierten Nachbehandlungsempfehlung dienten. In Zusammenschau aller Ergebnisse und unter Einschluss der DVSE-Mitgliedermeinungen konnte ein Grundkonzept ausgearbeitet werden.

Es wird über einen 39-jährigen Mann berichtet, der sich bei einem Sturz beim Kitesurfen eine primär traumatische Schulterluxation mit einer Läsion des Labrum glenoidale sowie eine Hill-Sachs-Impression zugezogen hat, welche konservativ therapiert wurde. Aufgrund einer posttraumatischen adhäsiven Kapsulitis wurde eine orale Glukokortikoidtherapie mittels Prednisolon empfohlen. Hierunter linderten sich die Schulterbeschwerden, jedoch entwickelte der Patient eine akute manische Episode und psychotische Symptome. Der Fallbericht soll Anwender von Glukokortikoiden für das Auftreten psychiatrischer Komplikationen sensibilisieren.

In a burning plasma state1–7, alpha particles from deuterium–tritium fusion reactions redeposit their energy and are the dominant source of heating. This state has recently been achieved at the US National Ignition Facility8using indirect-drive inertial-confinement fusion. Our experiments use a laser-generated radiation-filled cavity (a hohlraum) to spherically implode capsules containing deuterium and tritium fuel in a central hot spot where the fusion reactions occur. We have developed more efficient hohlraums to implode larger fusion targets compared with previous experiments9,10. This delivered more energy to the hot spot, whereas other parameters were optimized to maintain the high pressures required for inertial-confinement fusion. We also report improvements in implosion symmetry control by moving energy between the laser beams11–16and designing advanced hohlraum geometry17that allows for these larger implosions to be driven at the present laser energy and power capability of the National Ignition Facility. These design changes resulted in fusion powers of 1.5 petawatts, greater than the input power of the laser, and 170 kJ of fusion energy18,19. Radiation hydrodynamics simulations20,21show energy deposition by alpha particles as the dominant term in the hot-spot energy balance, indicative of a burning plasma state.

After decades of study, much remains unknown about the foraging practices of the earliest inhabitants of Puerto Rico. Here, we present an analysis of the malacological assemblages of two neighboring and (partially) contemporary early sites from the island's southwest, finding intriguing intersite differences in shellfish collection practices. We attribute this diversity to differences in site type, chronology, or changes in local coastal configuration. This work not only provides insights into prehistoric Puerto Rican foraging dynamics but also demonstrates the importance of considering factors including intra-age chronology, site type, and changes in paleoenvironmental conditions when considering ancient foraging practices.

La photo-vaporisation sélective de la prostate (PVP) par le laser Greenlight XPS®-180W (AMS, San José, USA) est une option dans le traitement chirurgical de l’hyperplasie bénigne de la prostate (HBP). L’objectif de notre travail était d’étudier les effets de la densité d’énergie délivrée pour la vaporisation prostatique sur les résultats postopératoires et le taux de PSA total sérique.

Durch körperliche Aktivität oder auch im Rahmen einer Ergometrie (Laufband oder Fahrrad) wird die Muskulatur derart belastet, dass sich die Herz-Kreislauf-Funktion verändert. Hierdurch ist ca. 2 h nach der Belastung der Anstieg der Kreatininkinase (CK) und der Laktatdehydrogenase (LDH) im Blut als Indikator für die Muskelbeanspruchung messbar. Auch der Wert des prostataspezifischen Antigens (PSA), insbesondere bei Männern, ist ein diagnostischer Parameter zur Beurteilung der Prostatafunktion, der bei Belastung der Prostataregion, wie z. B. Rennradfahren, beeinträchtigt werden kann. CK samt Isoenzyme, LDH und PSA können gezielt als Indikatoren für körperliche Belastung eingesetzt werden, insofern eine Aussage zur Vitalität des Patienten formuliert werden soll.

Dans le cancer de la prostate localisé, l’impact de l’hypogonadisme biochimique sur l’émergence et la progression du cancer est encore controversée. Notre objectif est de comparer les caractéristiques pathologiques et la récidive biologique (RB) à 5 ans après prostatectomie des patients atteints de cancer de la prostate (CaP) localisé en fonction du statut gonadique évalué par le total (TT) et la biodisponibilité (BT).

Atmospheric acidity is increasingly determined by carbon dioxide and organic acids1–3. Among the latter, formic acid facilitates the nucleation of cloud droplets4and contributes to the acidity of clouds and rainwater1,5. At present, chemistry–climate models greatly underestimate the atmospheric burden of formic acid, because key processes related to its sources and sinks remain poorly understood2,6–9. Here we present atmospheric chamber experiments that show that formaldehyde is efficiently converted to gaseous formic acid via a multiphase pathway that involves its hydrated form, methanediol. In warm cloud droplets, methanediol undergoes fast outgassing but slow dehydration. Using a chemistry–climate model, we estimate that the gas-phase oxidation of methanediol produces up to four times more formic acid than all other known chemical sources combined. Our findings reconcile model predictions and measurements of formic acid abundance. The additional formic acid burden increases atmospheric acidity by reducing the pH of clouds and rainwater by up to 0.3. The diol mechanism presented here probably applies to other aldehydes and may help to explain the high atmospheric levels of other organic acids that affect aerosol growth and cloud evolution.

AbstractLaser plasma accelerators (LPAs) enable the generation of intense and short proton bunches on a micrometre scale, thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material analysis. Being spectrally broadband, laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample properties. The rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm ${}^3$ for single proton bunches to allow for fast online feedback. Here we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm ${}^3$ . The detector achieves a spatial resolution below 500 $\unicode{x3bc}$ m and a sensitivity of 100 mGy. The detector performance is tested at a proton therapy cyclotron and an LPA proton source. The experiments’ primary focus is the characterization of the scintillator’s ionization quenching behaviour.

Currently great effort is made to find materials and technologies for the recycling of phosphate from wastewater. Herein, we present an in-depth study of the phosphate adsorption mechanism of a promising adsorber material, a Zn–Fe–Zr oxyhydroxide-based nanostructured precipitate. The behavior of the multicomponent nanomaterial, consisting of both crystalline and amorphous parts, is investigated via X-ray absorption fine structure spectroscopy and Mössbauer spectroscopy, revealing the importance of the nanostructured composition for the phosphate adsorption. We found evidence that adsorption takes place especially in the vicinity of iron sites in the amorphous part of the material.

The present work investigates PMMA colloids in a polymer matrix of linear chains as a simple and suitable system for complex nanocomposites. The investigation was based on SANS experiments, which were enabled by the use of deuterated colloids immersed in a matrix of linear hydrogenated chains. Cross-linked deuterated PMMA-colloids were synthesized with two different sizes (70 and 140 nm) by means of the surfactant-free emulsion polymerization method and the swelling behavior adjusted by varying the amount of added cross-linker (1.5 and 15.0 mol-%) at each size respectively. Colloid–polymer blends were prepared from colloid–polymer solutions. SANS experiments on these blends consistently revealed that colloids with a low cross-linking density could be homogeneously distributed throughout the matrix of linear chains. Fits with model form factors indicated the structure of fuzzy spheres for these molecularly dispersed microgels, which are slightly swollen with respect to their size and shape in H2O. Contrary to this, colloids with a high cross-linking density form aggregates in the blends. Despite this aggregation, we succeeded to unravel the shape and the size of single colloids by preparation of colloid–polymer blends where the colloid component is a binary mixture of deuterated and hydrogenated colloids both with a high cross-linking density. SANS on the latter blends suggested a core–shell particle in a lattice cell of an aggregate.

Reliable characterization of surficial marine sediments is essential to ensure the safe and economical design of subsea infrastructure for offshore energy facilities (e.g., seabed cables, pipelines, and shallow foundations). Conventional in situ testing methods (e.g., cone penetrometer test or T-bar) require careful interpretation to account for the effects of shallow embedment, whereas laboratory tests are affected by sampling-induced disturbances, the impact of which can be significant at the low stress levels relevant to the design of subsea infrastructure. This article describes two novel box-core–sized shallow penetrometers—the hemiball and toroid—which mimic the shape of subsea pipelines and have been designed to reliably measure the strength, consolidation, and frictional properties of surficial offshore sediments. The development and specification of the actuator used to operate these probes is also described. Another major benefit of these penetrometers, which are intended to be used offshore for on-deck testing aboard a survey vessel, is their capability to generate effective stress interpretations of the soil behavior, and this is made possible because pore pressure transducers are installed and monitored throughout testing. The results of a first laboratory proof test are presented to illustrate the potential of this novel sensor concept.