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Quantum electrodynamics (QED), the quantum field theory that describes the interaction between light and matter, is commonly regarded as the best-tested quantum theory in modern physics. However, this claim is mostly based on extremely precise studies performed in the domain of relatively low field strengths and light atoms and ions1–6. In the realm of very strong electromagnetic fields such as in the heaviest highly charged ions (with nuclear charge Z≫ 1), QED calculations enter a qualitatively different, non-perturbative regime. Yet, the corresponding experimental studies are very challenging, and theoretical predictions are only partially tested. Here we present an experiment sensitive to higher-order QED effects and electron–electron interactions in the high-Zregime. This is achieved by using a multi-reference method based on Doppler-tuned X-ray emission from stored relativistic uranium ions with different charge states. The energy of the 1s1/22p3/2J= 2 → 1s1/22s1/2J= 1 intrashell transition in the heaviest two-electron ion (U90+) is obtained with an accuracy of 37 ppm. Furthermore, a comparison of uranium ions with different numbers of bound electrons enables us to disentangle and to test separately the one-electron higher-order QED effects and the bound electron–electron interaction terms without the uncertainty related to the nuclear radius. Moreover, our experimental result can discriminate between several state-of-the-art theoretical approaches and provides an important benchmark for calculations in the strong-field domain.

La pose d’une dérivation ventriculaire externe au bloc opératoire par le neurochirurgien est un acte régulièrement pratiqué chez les patients de réanimation neurochirurgicale. Elle a pour objectif de traiter en urgence une hydrocéphalie aiguë. La spécificité de la prise en charge des patients porteurs de ce drainage nécessite de la part de l’infirmier des connaissances et des compétences spécifiques afin de prévenir et de gérer la survenue de complications. Ces informations indispensables sont détaillées dans cet article. External ventricular drainage is frequently performed in operating rooms by a neurosurgeon to relieve acute hydrocephalus and improve the patient’s clinical status in intensive care units. The management of patients undergoing this drainage device is complex: nurses must have the knowledge to provide safe and effective care and ensure the ability to perform a response to complications. The purpose of this document is to describe the knowledge necessary.

The aim of this study (CTOTC-09) was to assess the impact of “preformed” (at transplant) donor-specific anti-HLA antibody (DSA) and first year newly detected DSA (ndDSA) on allograft function at 3 years after pediatric heart transplantation (PHTx). We enrolled children listed at 9 North American centers. The primary end point was pulmonary capillary wedge pressure (PCWP) at 3 years posttransplant. Of 407 enrolled subjects, 370 achieved PHTx (mean age, 7.7 years; 57% male). Pre-PHTx sensitization status was nonsensitized (n = 163, 44%), sensitized/no DSA (n = 115, 31%), sensitized/DSA (n = 87, 24%), and insufficient DSA data (n = 5, 1%); 131 (35%) subjects developed ndDSA. Subjects with any DSA had comparable PCWP at 3 years to those with no DSA. There were also no significant differences overall between the 2 groups for other invasive hemodynamic measurements, systolic graft function by echocardiography, and serum brain natriuretic peptide concentration. However, in the multivariable analysis, persistent first-year DSA was a risk factor for 3-year abnormal graft function. Graft and patient survival did not differ between groups. In summary, overall, DSA status was not associated with worse allograft function or inferior patient and graft survival at 3 years, but persistent first-year DSA was a risk factor for late graft dysfunction.

Les auteurs présentent ici le cas clinique d’un chien de race Berger Belge Malinois, appartenant au ministère des Armées, présentant une détresse respiratoire au travail. Après un examen clinique attentif et la réalisation d’examens complémentaires, notamment une radiographie du thorax et un examen visuel des voies respiratoires supérieures sous anesthésie générale, une élongation du voile du palais, sans hyperplasie, a été diagnostiquée comme étant responsable des troubles respiratoires observés. Cette pathologie, atypique chez un chien dolichocéphale, est une des composantes du syndrome obstructif respiratoire. Elle est détaillée ici dans sa prise en charge médicale et chirurgicale, cette dernière nécessitant la mise en œuvre d’une palatoplastie simple consistant, après une anesthésie générale, à raccourcir le voile du palais par résection de sa partie terminale. En discussion, les auteurs rapportent plusieurs cas relatifs à cette pathologie, détectés sur les chiens de travail de race berger belge malinois au sein des Armées. Cette anomalie est en général mise en évidence vers l’âge de quatre à cinq ans et est responsable de l’apparition d’une intolérance à l’effort pouvant aller jusqu’au coup de chaleur, voire des épisodes de syncope, rendant le chien inapte au travail en ambiance chaude. La récupération physique et opérationnelle après l’intervention chirurgicale est totale et permet d’envisager un pronostic très favorable pour ces chiens.

In the final analysis, whatever disabling and unjust external intentions and actions, the desired socio-economic change will be done by Africans themselves, or it will not be done. Considering the [...]

Industry 4.0 is leading to rethink how operational decisions are made within companies. In particular, it raises the question of the evolution of employee involvement and autonomy in operational decision-making in a Lean 4.0 context. Dealing with such issues within companies presents high stakes but also involves many risks and difficulties. Therefore, it is necessary to test these new Industry 4.0 autonomy models within our Evolutive Learning Factories by developing a suitable experimental protocol. This article proposes a typology of scenarios and case studies that will serve as a basis for future experiments to study these issues in a standardized work context. This first study framework confirmed that the decisions induced by all the problems and opportunities encountered at the operational level are numerous and varied. This research work is a first step and opens up much broader research perspectives on the contribution of Industry 4.0 technologies in implementing new models of autonomy at work.

We report a 1.5-GHz Kerr-lens mode-locked (KLM) Yb:Y_2O_3 ring laser constructed by directly bonding the cavity components onto an aluminum baseplate. Stable unidirectional operation with an output power ≥10mW was obtained for pump-diode currents of 300–500 mA, corresponding to a total electrical power consumption of 1.5 W. After repetition rate stabilization, a comparison with a conventionally constructed identical laser showed a 50% reduction in phase noise. In free-running operation the bonded laser showed superior passive repetition rate stability. The bonding process follows an already proven integration approach in space-borne instrumentation, mapping a development pathway for KLM lasers in aerospace applications.

Volcanic hazards pose a potential threat to 8% of the world’s population, yet the economic literature on their short- and long-term consequences on household behavior and economic development is still in its infancy. In this article, we present the state of the literature and highlight knowledge gaps and methodological challenges inherent to the economic analysis of volcanic hazards and disasters. We first present the physical aspects of volcanic activity and describe available physical data. We then examine the concepts related to cost assessment of volcanic disasters. Finally, we discuss key micro and macroeconomic research questions economists should investigate and identify relevant methodological and data challenges. By highlighting research gaps in the “economics of volcanoes”, we provide future avenues of research that will address policy-relevant debates in the context of greater focus on risk mitigation, adaptation, and resilience policies aimed at mitigating natural hazards and disasters.

Pulsed laser ablation in liquid (PLAL) is a powerful method for producing nanoparticle colloids with a long-term stability despite the absence of stabilizing organic agents. The colloid stability involves different reactivities and chemical equilibria with complex ionic-specific effects at the nanoparticle/solvent interface which must be strongly influenced by their chemical composition. In this work, the surface composition of PLAL-produced gold nanoparticles in alkaline and saline (NaBr) water is investigated by X-ray photoelectron spectroscopy on free-flying nanoparticles, exempt from any substrate or radiation damage artifact. The Au 4f photoelectron spectra with a depth profiling investigation are used to evaluate the degree of nanoparticle surface oxidation. In alkaline water, the results preclude any surface oxidation contrary to the case of nanoparticles produced in NaBr solution. In addition, the analysis of Br 3d core-level photoelectron spectra agrees with a clear signature of Br on the nanoparticle surface, which is confirmed by a specific valence band feature. This experimental study is supported by DFT calculations, evaluating the energy balance of halide adsorption on different configurations of gold surfaces including oxidation or adsorbed salts.

Rheumatoid arthritis (RA) is an autoimmune disorder in which the immune system and its components attack the body's own tissues and factors. This disorder is characterized by inflammation of the joints, stiffness, swelling, overgrowth of the joint cartilage, and pain. The development of the disease has been closely associated with the presence of certain genetic elements called HLA alleles. However, only a few patients show a family-based trend in the incidence of RA, and the basis for susceptibility to RA is not clear. Studies have shown that a specific type of immune cell, the CD5+ B lymphocyte, is increased in patients with RA and is important in the production of rheumatoid factor and abnormal immune proteins called autoantibodies. The relationship between expression of CD5+ B lymphocytes and autoantibodies was assessed in 12 patients with rheumatoid arthritis and 52 healthy first-degree relatives. RA patients had more CD5+ B cells than their healthy relatives and unrelated healthy subjects. However, the levels of CD5+ B cells were high in RA patients and their relatives in five of the families studied. RA patients and their relatives frequently had increased total levels of the immune proteins known as immunoglobulins, and increased levels of autoantibodies (these elevated levels were found in 20 to 40 percent of patients and 10 to 20 percent of relatives). Also, it was found that the levels of IgM-type rheumatoid factor were correlated with the proportion of B cells that expressed the CD5 molecule. (Consumer Summary produced by Reliance Medical Information, Inc.)

Children and adolescents are highly vulnerable to the impact of sustained stressors during developmentally sensitive times. We investigated how demographic characteristics intersect with socioeconomic dimensions to shape the social patterning of quality of life and mental health in children and adolescents, two years into the COVID-19 pandemic.

Self-assembly of small amphiphilic molecules in water can lead to nanostructures of varying geometries with pristine internal molecular organization. Here we introduce a photoswitchable aramid amphiphile (AA), designed to exhibit extensive hydrogen bonding and robust mechanical properties upon self-assembly, while containing a vinylnitrile group for photoinduced cis–transisomerization. We demonstrate spontaneous self-assembly of the vinylnitrile-containing AA in water to form nanoribbons. Upon UV irradiation, trans-to-cisisomerizations occur concomitantly with a morphological transition from nanoribbons to nanotubes. The nanotube structure persists in water for over six months, stabilized by strong and collective intermolecular interactions. We demonstrate that the nanoribbon-to-nanotube transition is reversible upon heating and that switching between states can be achieved repeatedly. Finally, we use electron microscopy to capture the transition and propose mechanisms for nanoribbon-to-nanotube rearrangement and vice versa. The stability and switchability of photoresponsive AA nanostructures make them viable for a range of future applications.

Small-molecule self-assembly is an established route for producing high-surface-area nanostructures with readily customizable chemistries and precise molecular organization. However, these structures are fragile, exhibiting molecular exchange, migration and rearrangement—among other dynamic instabilities—and are prone to dissociation upon drying. Here we show a small-molecule platform, the aramid amphiphile, that overcomes these dynamic instabilities by incorporating a Kevlar-inspired domain into the molecular structure. Strong, anisotropic interactions between aramid amphiphiles suppress molecular exchange and elicit spontaneous self-assembly in water to form nanoribbons with lengths of up to 20 micrometres. Individual nanoribbons have a Young’s modulus of 1.7 GPa and tensile strength of 1.9 GPa. We exploit this stability to extend small-molecule self-assembly to hierarchically ordered macroscopic materials outside of solvated environments. Through an aqueous shear alignment process, we organize aramid amphiphile nanoribbons into arbitrarily long, flexible threads that support 200 times their weight when dried. Tensile tests of the dry threads provide a benchmark for Young’s moduli (between ~400 and 600 MPa) and extensibilities (between ~0.6 and 1.1%) that depend on the counterion chemistry. This bottom-up approach to macroscopic materials could benefit solid-state applications historically inaccessible by self-assembled nanomaterials.

Abstract:This text mobilizes the theoretical frameworks of intersectionality and coloniality to analyze the figure of the Haitian poto-mitan woman—she who acts as a “central pillar”—a figure that was constructed during the history of colonialism. Colonial and postslavery relations initiated a process of coformation and coproduction and determined power relations that still traverse Haiti. They connect individual, national, and global dynamics that intertwine, frequently characterizing the poto-mitan women’s workforce as deviant. This article historicizes the poto-mitan woman and unveils how common conceptualizations appropriate the body and time of women assigned the duties of support and protection.

ABSTRACTEurope and now the United States are characterized by the growing presence of populist parties and leaders able to attract a significant share of the electorate. The successful strategy of right-wing populist politicians consists in proposing a series of discourses based on a differentiation between an endangered “Us” and a threatening “Them.” The protection of the “Us” community from the evil “Them” is often expressed through the necessity of closing the national border. This measure is a key discursive resource incorporated in their speeches. However, is the border only presented by right-wing populist leaders as a boundary which has to be controlled, securitized, and sealed? Based on the analysis of discourses produced by Viktor Orbán, the only long-standing European populist leader in power, the research shows that right-wing populist discourses can be based on opposed and complementary conceptions of the state border to entrench the opposition between “Us” and “Them.”

Purpose:To determine if three lumbopelvic-hip endurance tests can identify basketball players at risk for lower extremity injury.Methods:High school basketball players (n = 150) volunteered. The unilateral wall sit hold, trunk flexion hold, and horizontal trunk hold tests were administered prior to the season. Non-contact lower extremity injuries were tracked.Results:Players with wall sit hold times of 35 seconds or less had 2.6 times greater odds for occurrence of a lower extremity injury than those with hold times of longer than 35 seconds (90% confidence interval [CI]: 1.05 to 7.98). Females with wall sit times of 35 seconds or less were 2.75 times more likely to suffer a lower extremity injury than females with times of longer than 35 seconds (90% CI: 0.78 to 9.72). Males with wall sit hold times of 32 seconds or less had 2.38 times greater odds to sustain an injury compared to males with longer hold times (90% CI: 0.56 to 10.14). The horizontal trunk flexion hold and trunk flexion hold tests did not identify players at risk for injury.Conclusions:The wall sit hold identified participants with elevated risk for lower extremity injury during a basketball season. Participants at higher risk had shorter wall sit hold times.[[Athletic Training & Sports Health Care. 2020;12(3):127–134.]

Das Verbundvorhaben „Stärken oder schützen? Über Inhalte, Methoden und kollektive Orientierungen sexualpädagogischer und gewaltpräventiver Praxis – ein Professionalisierungsbeitrag“ der Universität Münster und des Universitätsklinikums Hamburg-Eppendorf untersucht die pädagogischen Praxen der Sexualpädagogik und der Prävention sexualisierter Gewalt. Es zielt auf eine empirisch fundierte Wissenserweiterung sowie eine konzeptionelle Weiterentwicklung der jeweiligen pädagogisch-professionellen Praxis ab. Damit wird die Frage nach dem Verhältnis des Schutzes vor Risiken, der Stärkung des Selbstschutzes von Kindern und Jugendlichen und der Bildung zur sexuellen Selbstbestimmung aufgegriffen. Durch die Zusammenschau von sexualpädagogischer und gewaltpräventiver Praxis soll ein verbesserter Umgang mit Antinomien und Paradoxien in der Verhinderung sexualisierter Gewalt erreicht werden.

Cell migration profoundly influences cellular function, often resulting in adverse effects in various pathologies including cancer metastasis. Directly assessing and quantifying the nanoscale dynamics of living cell structure and mechanics has remained a challenge. At the forefront of cell movement, the flat actin modules─the lamellipodium and the lamellum─interact to propel cell migration. The lamellipodium extends from the lamellum and undergoes rapid changes within seconds, making measurement of its stiffness a persistent hurdle. In this study, we introduce the fast-quantitative imaging (fast-QI) mode, demonstrating its capability to simultaneously map both the lamellipodium and the lamellum with enhanced spatiotemporal resolution compared with the classic quantitative imaging (QI) mode. Specifically, our findings reveal nanoscale stiffness gradients in the lamellipodium at the leading edge, where it appears to be slightly thinner and significantly softer than the lamellum. Additionally, we illustrate the fast-QI mode’s accuracy in generating maps of height and effective stiffness through a streamlined and efficient processing of force–distance curves. These results underscore the potential of the fast-QI mode for investigating the role of motile cell structures in mechanosensing.

The article discusses about the risk management in the metaverse, a new way of talking about cyberspace. It further discusses about the pivotal role of the insurance in metaverse; the risks associated with the metaverse materialize and metaverse users more claims under their traditional insurance policies; existing policies insuring risk in the real world and the risks associated with digital assets.

The surface chemistry of gold nanoparticles produced by the pulsed laser ablation in liquids method is investigated by X-ray photoelectron spectroscopy (XPS). The presence of surface oxide expected on these systems is investigated using synchrotron radiation in conditions close to their original state in solvent but free from substrate or solvent effects which could affect the interpretation of spectroscopic observations. For that purpose we performed the experiment on a controlled free-standing nanoparticle beam produced by combination of an atomizer and an aerodynamic lens system. These results are compared with those obtained by the standard situation of deposited nanoparticles on silicon substrate. An accurate analysis based on Bayesian statistics concludes that the existence of oxide in the free-standing conditions cannot be solely confirmed by the recorded core-level 4f spectra. If present, our data indicate an upper limit of 2.15 ± 0.68% of oxide. However, a higher credence to the hypothesis of its existence is brought by the structureless valence profile of the free-standing beam. Moreover, the cross-comparison with the deposited nanoparticles case clearly evidences an important misleading substrate effect. Experiment with free-standing nanoparticles is then demonstrated to be the right way to further investigate oxidation states on Au nanoparticles.

•Safety is an important attribute of public open spaces for pedestrians.•Land use diversity positively influences walkability at the micro-scale.•In Belenzinho, the design of public open spaces is not safe for pedestrians.•Public space, presently dedicated to cars, can be allocated to improve walkability.•Comprehensive TOD policies must promote pedestrian-oriented public open spaces.

ABSTRACTMuseums are central places for participating in the territorial building of the nation-state. They can also play a key role in proposing a spatial structure of the European Union. Certain museums sponsored by member states of the EU have organized exhibitions that refer to the Schengen Treaty and its geographical implications in Europe. However, are these exhibitions promoting a territoriality based on the cross-border mobility of EU citizens favored by this Treaty? Based on a comparative analysis, the research shows that the representation of European integration in these museums can be above all the intensification of state-managed territoriality, meaning the expression of a public power that filters access in space through border controls. This representation can be explained by the specific context within which curators define their contents.

Coumermycin A1 is a natural aminocoumarin that inhibits bacterial DNA gyrase, a member of the GHKL proteins superfamily. We report here the first cocrystal structures of gyrase B bound to coumermycin A1, revealing that one coumermycin A1 molecule traps simultaneously two ATP-binding sites. The inhibited dimers from different species adopt distinct sequence-dependent conformations, alternative to the ATP-bound form. These structures provide a basis for the rational development of coumermycin A1 derivatives for antibiotherapy and biotechnology applications.

ABSTRACTA new phase of print capitalism was launched at the transition from the twentieth to the twenty-first century with the appearance of free dailies circulated in the large cities of the Western world. The market performance of this form of press depends strongly on the non-price quality of its news, which is produced for and used by a public that accepts its reading will be interrupted by adverts. However, what are the socio-cultural frames within which this non-price quality is defined? The current article explores the value of “banal cosmopolitanism” as a driving force of this non-price quality. The investigation is based on a case study of the newspaper L’essentielin Luxembourg.

We reveal that the axial stiffness of amyloid fibrils is inversely correlated with their cross-sectional area. Because amyloid fibrils’ stiffness is determined by hydrogen bond (H-bond) density with a linear correlation, our finding implies that amyloid fibrils with larger radial sizes are generally softer and have lower density H-bond networks. In silico calculations show that the stiffness–size relationship of amyloid fibrils is, indeed, driven by the packing densities of residues and H-bonds. Our results suggest that polypeptide chains which form amyloid fibrils with narrow cross sections can optimize packing densities in the fibrillar core structure, in contrast to those forming wide amyloid fibrils. Consequently, the density of residues and H-bonds that contribute to mechanical stability is higher in amyloid fibrils with narrow cross sections. This size dependence of nanomechanics appears to be a global property of amyloid fibrils, just like the well-known cross-β sheet topology.

Data on the clinical importance of newly detected donor‐specific anti‐HLA antibodies (ndDSAs) after pediatric heart transplantation are lacking despite mounting evidence of the detrimental effect of de novo DSAs in solid organ transplantation. We prospectively tested 237 pediatric heart transplant recipients for ndDSAs in the first year posttransplantation to determine their incidence, pattern, and clinical impact. One‐third of patients developed ndDSAs; when present, these were mostly detected within the first 6 weeks after transplantation, suggesting that memory responses may predominate over true de novo DSA production in this population. In the absence of preexisting DSAs, patients with ndDSAs had significantly more acute cellular rejection but not antibody‐mediated rejection, and there was no impact on graft and patient survival in the first year posttransplantation. Risk factors for ndDSAs included common sensitizing events. Given the early detection of the antibody response, memory responses may be more important in the first year after pediatric heart transplantation and patients with a history of a sensitizing event may be at risk even with a negative pretransplantation antibody screen. The impact on late graft and patient outcomes of first‐year ndDSAs is being assessed in an extended cohort of patients. The authors use a large multi‐institutional cohort to establish the incidence, pattern, and early clinical impact of newly detected donor‐specific antibodies after pediatric heart transplantation. Also see an editorial from Pajaro et al on page 2107, and related CTOTC articles on pages 2135and 2148.

The chemical and geometrical structure of free-standing carbon dots (Cdots) prepared from the pyrolysis of N-hydroxysuccinimide (NHS) have been characterized using X-ray photoelectron spectroscopy (XPS). An aerodynamic lens system was used to generate a sufficient particle density of monodispersed Cdots for XPS studies at the PLEIADES beamline at the SOLEIL synchrotron facility. Varying the X-ray excitation energy between 315 and 755 eV allows probing of the Cdots from the surface toward their core, owing to the kinetic energy dependence of the photoelectron inelastic mean free path. The C 1s, O 1s, and N 1s core-levels were recorded with high-spectral resolution to identify their main chemical components and branching ratios. While high-resolution transmission electron microscopy (HRTEM) reveals a defective graphitic core, the C 1s spectrum evidence two main peaks similar to those measured from the solid NHS. Their relative abundance as a function of the probing depth is strongly related to the chemical composition of the ligand shell that does not vary substantially over the first 3.4 nm. Combining the depth-resolved XPS and HRTEM studies, it was concluded that the Cdots possess a graphitic core surrounded by a relatively homogeneous shell of at least 3.4 nm thickness with a composition similar to that of the solid NHS.

This study sought to determine outcomes of adult recipients of early adolescent (EA) (10 to 14 years) donor hearts.

Precision agriculture for banana crops has been little investigated so far. The main difficulty to implement precision agriculture methods lies in the asynchronicity of this crop: after a few cycles, each plant has its own development stage in the field. Indeed, maps of agronomical interest are difficult to produce from plant responses without implementing new methods. The present study explores the feasibility to derive a spatially relevant indicator from the date of flowering and the date of maturity (time to harvest). The time between these dates (TFM) may give insight in spatial distribution of vigor. The study was carried out using production data from 2015 acquired in a farm from Cameroon. Data from individual plants that flowered at different weeks were gathered so as to increase the density of TFM sampling. The temporal variability of TFM, which is induced by weather and operational constraints, was compensated by centering TFM data on their medians (TFMc). The mapping of TFMc was obtained using a classical kriging method. Spatial structures highlighted by TFMc either at the farm level or at the plot level, suggest that such maps could be used to support agronomic decisions.

Amyloids are fibrillar nanostructures of proteins that are assembled in several physiological processes in human cells (e.g., hormone storage) but also during the course of infectious (prion) and noninfectious (nonprion) diseases such as Creutzfeldt-Jakob and Alzheimer’s diseases, respectively. How the amyloid state, a state accessible to all proteins and peptides, can be exploited for functional purposes but also have detrimental effects remains to be determined. Here, we measure the nanomechanical properties of different amyloids and link them to features found in their structure models. Specifically, we use shape fluctuation analysis and sonication-induced scission in combination with full-atom molecular dynamics simulations to reveal that the amyloid fibrils of the mammalian prion protein PrP are mechanically unstable, most likely due to a very low hydrogen bond density in the fibril structure. Interestingly, amyloid fibrils formed by HET-s, a fungal protein that can confer functional prion behavior, have a much higher Young’s modulus and tensile strength than those of PrP, i.e., they are much stiffer and stronger due to a tighter packing in the fibril structure. By contrast, amyloids of the proteins RIP1/RIP3 that have been shown to be of functional use in human cells are significantly stiffer than PrP fibrils but have comparable tensile strength. Our study demonstrates that amyloids are biomaterials with a broad range of nanomechanical properties, and we provide further support for the strong link between nanomechanics and β-sheet characteristics in the amyloid core.

La pose d’une dérivation ventriculaire externe au bloc opératoire par le neurochirurgien est un acte régulièrement pratiqué chez les patients de réanimation neurochirurgicale. Elle a pour objectif de traiter en urgence une hydrocéphalie aiguë. La spécificité de la prise en charge des patients porteurs de ce drainage nécessite de la part de l’infirmier des connaissances et des compétences spécifiques afin de prévenir et de gérer la survenue de complications. Ces informations indispensables sont détaillées dans cet article. External ventricular drainage is frequently performed in operating rooms by a neurosurgeon to relieve acute hydrocephalus and improve the patient’s clinical status in intensive care units. The management of patients undergoing this drainage device is complex: nurses must have the knowledge to provide safe and effective care and ensure the ability to perform a response to complications. The purpose of this document is to describe the knowledge necessary.

The mechanical properties of living cells reflect their physiological and pathological state. In particular, cancer cells undergo cytoskeletal modifications that typically make them softer than healthy cells, a property that could be used as a diagnostic tool. However, this is challenging because cells are complex structures displaying a broad range of morphologies when cultured in standard 2D culture dishes. Here, we use adhesive micropatterns to impose the cell geometry and thus standardize the mechanics and morphologies of cancer cells, which we measure by atomic force microscopy (AFM), mechanical nanomapping, and membrane nanotube pulling. We show that micropatterning cancer cells leads to distinct morphological and mechanical changes for different cell lines. Micropatterns did not systematically lower the variability in cell elastic modulus distribution. These effects emerge from a variable cell spreading rate associated with differences in the organization of the cytoskeleton, thus providing detailed insights into the structure–mechanics relationship of cancer cells cultured on micropatterns. Combining AFM with micropatterns reveals new mechanical and morphological observables applicable to cancer cells and possibly other cell types.

Introduction:A positive crossmatch (+ XM) has traditionally been associated with adverse outcomes following pediatric heart transplantation. However, more recent studies suggest that favorable intermediate-term outcomes may be achieved despite a + XM.Hypothesis:Children with a + XM have similar long-term survival but higher rate of complications, such as rejection, coronary vasculopathy (CAV), and infection, compared to patients with a negative XM.Methods:The Pediatric Heart Transplant Society Registry database was queried from 2010-2021 for all patients <18 years of age with a known XM. Baseline demographics were compared between + XM and negative XM groups using appropriate parametric and non-parametric group comparisons. Multiphase survival analysis curves were constructed for each outcome to describe both short- and long-term hazard. Similar correlations were performed for different types of + XM (cytotoxic vs Flow).Results:Of 4599 transplants during the study period, XM results were available for 3914, with + XM in 373 (9.5%). There were 70 cases with CDC + XM (39 B-cell, 31 T-cell) and an additional 149 (90 B-cell, 59 T-cell) with flow + XM where CDC XM was either negative, unknown, or not performed. 5-year survival was significantly different in the 2 groups (HR=1.3, p=0.04). Patients with a +XM had shorter time to first rejection (p=.0001) and detection of CAV (p=0.01), while the risk of infection was similar (p=0.11) [Figure]. When comparing CDC+ to Flow+/CDC- patients, there was no difference in 5-year survival or time to first rejection, however CDC+ patients had shorter time to CAV detection (p= 0.01).Conclusions:Pediatric patients transplanted across a + XM experience earlier rejection, earlier development of CAV, and increased graft loss compared to patients with a negative crossmatch. The risk of heart transplantation against a + XM must be balanced with the ongoing risk of waitlist mortality.

Introduction:Ventriculo-arterial coupling (VAC) ratio (normal value: 0.6 - 1.2) is worse in children with dilated cardiomyopathy compared to controls and is associated with poor heart failure (HF) outcomes. It has not been studied in patients on oral HF medications. Our aim was to study VAC ratio as a measure of response to therapy and its ability to predict worse outcomes in this population.Methods:A retrospective study of DCM patients < 21 years on oral heart failure medications was conducted between 2010 and 2022 at the Children's Hospital At Montefiore. Medication data, NYHA functional class, and outcomes (mechanical circulatory support, transplantation, or death) were collected. A single observer analyzed the initial and the last echocardiograms on optimal HF therapy to calculate arterial elastance (EA), ventricular elastance (EES), and VAC ratio. Patients with and without outcomes were compared using chi-square & Mann Whitney tests, as appropriate.Results:Thirty-one patients (median age at diagnosis 1.25 (IQR 7.7) years) were followed for a median of 4.92 (IQR 11) years. There was a significant improvement in the VAC ratio (mean 1.85 vs 1.46, SEM 0.17, P=0.02) from diagnosis to the last follow-up with a median change of -13.5%. There was a statistically significant association between the percent change in VAC and change in the NYHA class (P=0.0001). Outcome events occurred in 7 patients; one required mechanical circulatory support, two died, and four underwent transplants. Patients with an outcome event had a worse VAC ratio both at diagnosis (P=0.03) and at the last follow-up (P=0.0001) and a worse NYHA class (P=0.001) at the last follow-up (Table).Conclusion:VAC is a potential biomarker for response to therapy and is associated with poor outcomes in pediatric DCM. It provides mechanistic insights into HF in this population.

We investigate the efficient heating of quasi-free electrons during the interaction of short infrared laser pulses with large rare-gas clusters. In the framework of our mean-field classical transport simulation we are able to explain the emission of characteristic x-rays at moderate laser intensities (${\rm I}\sim 10^{15}$Wcm$^{ - 2})$where the ponderomotive energy of the electrons is by far to low to allow for the creation of inner-shell vacancies. We identify large-angle elastic electron-ion scattering as an important heating mechanism at moderate laser intensities.

Les expériences que nous avons réalisées sur le Laser Ultra Court Accordable du CEA Saclay permettent d'observer l'émission de photons X dans la gamme 1-5 keV lors de l'irradiation d'agrégats de gaz rare (Ar, Kr et Xe comprenant entre 103et 106atomes par agrégat) avec un laser femtoseconde de puissance (Ipicjusqu'à 1017W/cm$^{2})$. En plus de la distribution des états de charge des ions responsables de l'émission X, la technique de spectroscopie X que nous utilisons permet de mesurer les taux absolus de photons émis dans 4$\pi $par impulsion laser en fonction des paramètres gouvernant l'interaction dans des conditions contrôlées. Nous avons déterminé la sensibilité des paramètres physiques régissant la production du rayonnement X pendant l'interaction, ce qui permet d'accéder à l'optimisation de cette source. Cet article est plus particulièrement dédié aux résultas relatifs à l'évolution du taux d'X avec l'éclairement laser, d'une part, et avec la durée de l'impulsion laser, d'autre part.

Lors de campagnes d'expériences réalisées sur le Laser Ultra Court Accordable du CEA/Saclay, nous avons étudié le rayonnement X, tant qualitativement (spectroscopie et énergie moyenne des photons) que quantitativement (taux absolus et lois d'évolution), émis lors de l'interaction d'un jet effusif d'agrégats de gaz rare (Ar, Kr, Xe comprenant entre 104et 106atome/agrégat) avec un laser femtoseconde de puissance (éclairement jusqu'à quelques 1017W/cm2). Les résultats présentés dans ce manuscrit sont uniquement dédiés aux agrégats d'Ar pour lesquels nous avons observé un rayonnement X issu d'ions fortement multichargés (jusqu'à l'Ar16+) présentant des lacunes en couches K. La technique de spectroscopie X utilisée a permis de déterminer pour la première fois des taux absolus ainsi que les lois d'évolution de l'émission X en fonction de l'ensemble des paramètres gouvernant l'interaction (intensité, polarisation, longueur d'onde et durée du pulse laser aussi bien que taille, densité et numéro atomique des agrégats).

Nous avons étudié le rayonnement X provenant d'ions fortement multichargés (≥24+) présentant des lacunes en couche L produits lors de l'irradiation d'agrégats de xénon par des impulsions lumineuses issues d'un laser femtoseconde de puissance. Les résultats obtenus lors de la toute dernière campagne d'expériences réalisée auprès du serveur LUCA du SPAM/DRECAM au CEA/Saclay mettent en cause certains travaux antérieurs [4-6]. Des divergences marquées apparaissent tant au niveau de l'interprétation des spectres X que sur la variation du taux d'émission en fonction de l'éclairement et de la longueur d'onde.

Posttransplant lymphoproliferative disorder (PTLD) is a diversely manifesting group of lymphoid or plasmacytic proliferations found in solid organ and bone marrow transplant recipients. PTLD occurs as a result of immunosuppression and is often driven by the Epstein Barr virus. Although most commonly of B-cell origin, similar to B-cell lymphomas, PTLD can rarely present as a plasmacytic process, resembling multiple myeloma. Although more common in adults, 8 cases of plasmacytoma-like PTLD have been reported in pediatric renal and combined small bowel-liver transplant recipients. Here, we present a rare report of a plasmacytoma-like PTLD case in a pediatric heart transplant recipient.