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Structures in the Universe, ranging from globular clusters to entire galaxies, are not described by standard statistical mechanics at equilibrium. Instead, they are formed through a process of a very different nature, called violent relaxation that is now known to be possible also in other systems that exhibit long-range interactions. This mechanism was proposed theoretically and modelled numerically, but never directly observed in any physical system. Here, we develop a table-top experiment allowing us to directly observe violent relaxation in an optical setting. The resulting optical dynamics can also be likened to the formation of an analogue 2D-galaxy through the analogy of the underlying equations, where we can control a range of parameters, including the nonlocal interacting potential, allowing us to emulate the physics of gravitational quantum and classical dark matter models. Large structure in the Universe, such as galaxies, are believed to form by a process called violent relaxation, which occurs over millions of years. The authors present a nonlinear optics experiment which shows direct observation of violent relaxation, whose evolution can be related to the equations governing galaxy formation. [ABSTRACT FROM AUTHOR]

Background: Recently, the combination of venetoclax plus a hypomethylating agent (HMA; azacitidine ordecitabine) or low‐dose cytarabine (LDAC) showed promise in Phase III trials in previously untreated AML. In France at the time of this study, venetoclax was not yet approved for AML and there were therefore no formal usage recommendations. Here we report the first study in a French cohort that assessed venetoclax in combination with existing treatments for AML under real‐life conditions. Method: This retrospective, real‐life study collected data on venetoclax use and management in a French cohort with acute myeloid leukemia (AML) ineligible for intensive chemotherapy. Result: Of 118 patients, 81 were in second line/beyond (71.6% also hypomethylating agent [HMA]; 23.5% lowdose cytarabine [LDAC]) and 37 in first line. For venetoclax initiation, 57.3% underwent ramp up and 74.6% were hospitalized. Median venetoclax duration was 2.5 months (range 0.03‐16.2). With all treatment lines and regimens, most common grade 3/4 adverse events were hematologic (overall 96.4% of patients) and infections (57.1%). Dosage adjustments for drug interactions and safety varied between centers. In second‐line/beyond, median progression‐free survival was 4.0 months (95% confidence interval [CI] 2.7‐12.8) with venetoclax‐HMA and 3.4 months (1.3‐8.9) with venetoclax‐LDAC; overall response rate was 51.9% and 41.2%, respectively. Thus, we showed that venetoclax‐based treatment yields promising findings in patients with AML, but to address treatment complexity, practice harmonization is needed. [ABSTRACT FROM AUTHOR]

BACKGROUND: The relationship between birth mode, with the medical care it implies, and women's subjective experiences of childbirth is known to be complex and multifactorial. Considering these complexities, this study aimed to explore the relationship between birth mode and women's childbirth experiences. METHOD: A cross-sectional survey on the most recent childbirth was distributed in three French maternity wards between September and October 2019 as part of a mixed-method research design. All women over 18 years of age who had given birth in the wards in the previous 3 days were eligible to participate. To study these qualitative variables in a finite population, 258 women were recruited by use of a simple random sampling technique. They answered survey questions concerning both sociodemographic data and information about the childbirth experience. The correlation between the survey variables was studied using a Pearson chi-square test. RESULTS: Combined data indicated a positive correlation between childbirth experiences and birth mode. Furthermore, data showed that emergency cesarean births had the most negative impact on respondents' childbirth experiences. Compared to respondents who had an emergency cesarean, those who had a non-instrumental vaginal birth used the words "happiness" (p =.0095), "wonder" (p =.0005), and "power" (p =.0384) significantly more. Additionally, compared to respondents who had a vaginal birth, those who had an emergency cesarean described their childbirth significantly more with the words "fear" (p <.0001) and "powerlessness" (p <.0001). CONCLUSIONS: Although several studies have already highlighted the relationship between birth mode and women's negative childbirth experiences, our results show that this relationship can also be read through the lesser use of positive words to describe this subjective experience, thus refining our knowledge and understanding of this event. [ABSTRACT FROM AUTHOR]

A phase transition between disordered and quasi-ordered states, known as the Berezinskii–Kosterlitz–Thouless transition, has now been revealed in a two-dimensional photonic 'fluid'. The interplay between phase singularities and coherence may lead to new vortex-based optical applications. [ABSTRACT FROM AUTHOR]

The article announces video "Suspended" as winner of 2019 Ivan Juritz Prize for best visual arts.

Quantum fluids of light merge many-body physics and nonlinear optics, revealing quantum hydrodynamic features of light when it propagates in nonlinear media. One of the most outstanding evidence of light behaving as an interacting fluid is its ability to carry itself as a superfluid. Here, we report a direct experimental detection of the transition to superfluidity in the flow of a fluid of light past an obstacle in a bulk nonlinear crystal. In this cavityless all-optical system, we extract a direct optical analog of the drag force exerted by the fluid of light and measure the associated displacement of the obstacle. Both quantities drop to zero in the superfluid regime characterized by a suppression of long-range radiation from the obstacle. The experimental capability to shape both the flow and the potential landscape paves the way for simulation of quantum transport in complex systems. [ABSTRACT FROM AUTHOR]

Alpha-synuclein is known to bind to small unilamellar vesicles (SUVs) via its N terminus, which forms an amphipathic alpha-helix upon membrane interaction. Here we show that calcium binds to the C terminus of alpha-synuclein, therewith increasing its lipid-binding capacity. Using CEST-NMR, we reveal that alpha-synuclein interacts with isolated synaptic vesicles with two regions, the N terminus, already known from studies on SUVs, and additionally via its C terminus, which is regulated by the binding of calcium. Indeed, dSTORM on synaptosomes shows that calcium mediates the localization of alpha-synuclein at the pre-synaptic terminal, and an imbalance in calcium or alpha-synuclein can cause synaptic vesicle clustering, as seen ex vivo and in vitro. This study provides a new view on the binding of alpha-synuclein to synaptic vesicles, which might also affect our understanding of synucleinopathies. [ABSTRACT FROM AUTHOR]

ABSTRACT Alzheimer's disease (AD) is the main cause of dementia in the elderly population. Over 30 million people worldwide are living with dementia and AD prevalence is projected to increase dramatically in the next two decades. In terms of neuropathology, AD is characterized by two major cerebral hallmarks: extracellular β-amyloid (Aβ) plaques and intracellular Tau inclusions, which start accumulating in the brain 15-20 years before the onset of symptoms. Within this context, the scientific community worldwide is undertaking a wide research effort to detect AD pathology at its earliest, before symptoms appear. Neuroimaging of Aβ by positron emission tomography (PET) is clinically available and is a promising modality for early detection of Aβ pathology and AD diagnosis. Substantive efforts are ongoing to develop advanced imaging techniques for early detection of Tau pathology. Here, we will briefly describe the key features of Tau pathology and its heterogeneity across various neurodegenerative diseases bearing cerebral Tau inclusions (i.e., tauopathies). We will outline the current status of research on Tau-specific PET tracers and their clinical development. Finally, we will discuss the potential application of novel super-resolution and label-free techniques for investigating Tau pathology at the experimental level and their potential application for AD diagnosis. Microsc. Res. Tech. 79:677-683, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

New strategies for visualizing self-assembly processes at the nanoscale give deep insights into the molecular origins of disease. An example is the self-assembly of misfolded proteins into amyloid fibrils, which is related to a range of neurodegenerative disorders, such as Parkinson's and Alzheimer's diseases. Here, we probe the links between the mechanism of α-synuclein (AS) aggregation and its associated toxicity by using optical nanoscopy directly in a neuronal cell culture model of Parkinson's disease. Using superresolution microscopy, we show that protein fibrils are taken up by neuronal cells and act as prion-like seeds for elongation reactions that both consume endogenous AS and suppress its de novo aggregation. When AS is internalized in its monomeric form, however, it nucleates and triggers the aggregation of endogenous AS, leading to apoptosis, although there are no detectable cross-reactions between externally added and endogenous protein species. Monomer-induced apoptosis can be reduced by pretreatment with seed fibrils, suggesting that partial consumption of the externally added or excess soluble AS can be significantly neuroprotective. [ABSTRACT FROM AUTHOR]

The assessment of BRCA1 and BRCA2 coding sequences to identify pathogenic mutations associated with inherited breast/ovarian cancer syndrome has provided a method to identify high-risk individuals, allowing them to seek preventative treatments and strategies. However, the current test is expensive, and cannot differentiate between pathogenic variants and those that may be benign. Focusing only on one of the two BRCA partners, we have developed a biological assay for haploinsufficiency of BRCA1. Using a series of EBV-transformed cell lines, we explored gene expression patterns in cells that were BRCA1 wildtype compared to those that carried (heterozygous) BRCA1 pathogenic mutations. We identified a subset of 43 genes whose combined expression pattern is a sensitive predictor of BRCA1 status. The gene set was disproportionately made up of genes involved in cellular differentiation, lending credence to the hypothesis that single copy loss of BRCA1 function may impact differentiation, rendering cells more susceptible to undergoing malignant processes. [ABSTRACT FROM AUTHOR]

Rafflesia is a genus of holoparasitic plants endemic to Southeast Asia that has lost the ability to undertake photosynthesis. With short-read sequencing technology, we assembled a draft sequence of the mitochondrial genome of Rafflesia lagascae Blanco, a species endemic to the Philippine island of Luzon, with ∼350× sequencing depth coverage. Using multiple approaches, however, we were only able to identify small fragments of plastid sequences at low coverage depth (<2×) and could not recover any substantial portion of a chloroplast genome. The gene fragments we identified included photosynthesis and energy production genes (atp, ndh, pet, psa, psb, rbcL), ribosomal RNA genes (rrn16, rrn23), ribosomal protein genes (rps7, rps11, rps16), transfer RNA genes, as well as matK, accD, ycf2, and multiple nongenic regions from the inverted repeats. None of the identified plastid gene sequences had intact reading frames. Phylogenetic analysis suggests that ∼33% of these remnant plastid genes may have been horizontally transferred from the host plant genus Tetrastigma with the rest having ambiguous phylogenetic positions (<50% bootstrap support), except for psaB that was strongly allied with the plastid homolog in Nicotiana. Our inability to identify substantial plastid genome sequences from R. lagascae using multiple approaches—despite success in identifying and developing a draft assembly of the much larger mitochondrial genome—suggests that the parasitic plant genus Rafflesia may be the first plant group for which there is no recognizable plastid genome, or if present is found in cryptic form at very low levels. [ABSTRACT FROM PUBLISHER]

This article is composed of two parts. The first part is aimed at providing an overview on the kinetic description of random nonlinear waves considering the one-dimensional nonlinear Schrödinger (NLS) equation as a representative model of optical wave propagation. We expose, in particular, the key problem of achieving a closure of the infinite hierarchy of moment equations for the random field. The hierarchy is closed at the first order when the statistics of the random wave is non-stationary or when the response time of the nonlinearity is non-instantaneous, which, respectively, leads to the Vlasov kinetic equation and the weak-Langmuir turbulence equation. When the amount of non-stationary statistics is comparable to the amount of non-instantaneous nonlinearity, we derive a generalized Vlasov-Langmuir equation that provides a unified formulation of the Vlasov and Langmuir approaches. On the other hand, when the statistics of the random wave is stationary and the nonlinear response instantaneous, the closure of the hierarchy of moment equations requires a second-order perturbation expansion procedure, which leads to the Hasselmann (or wave turbulence) kinetic equation. Contrarily to the Vlasov and Langmuir equations, the Hasselmann equation is irreversible, a feature which is expressed by a H-theorem of entropy growth that describes wave thermalization toward the thermodynamic equilibrium distribution, i.e. the Rayleigh-Jeans (RJ) spectrum. In the second part of the paper, we discuss a process of anomalous thermalization by considering the example of the scalar NLS equation whose integrability is broken by the presence of third-order dispersion. The anomalous thermalization is characterized by an irreversible evolution of the wave toward an equilibrium state of a fundamental different nature than the conventional RJ equilibrium state. The wave turbulence kinetic equation reveals that the anomalous thermalization is due to the existence of a local invariant in frequency space J, which originates in degenerate resonances of the system. In contrast to integral invariants that lead to a generalized RJ distribution, here, it is the local nature of the invariant J that makes the new equilibrium states fundamentally different than the usual RJ equilibrium states. We study in detail the anomalous thermalization by means of numerical simulations of the NLS equation and of the wave turbulence equation by using an improved criterion of applicability of the kinetic theory. The spectrum of the field is shown to exhibit an intriguing asymmetric deformation, which is characterized by the unexpected emergence of a constant spectral pedestal in the long-term evolution of the field. It turns out that the local invariant J explains all the essential properties of the anomalous thermalization of the wave. [ABSTRACT FROM AUTHOR]

We retrospectively analyzed 13 episodes of candidemia observed between July 1990 and July 1995 in human immunodeficiency virus (HIV)-infected adults. Candidemia was nosocomially acquired by 11 patients, among whom nine had a central venous catheter (CVC). Twelve cases were of stage C2/C3 according to the 1993 classification of the Centers for Disease Control and Prevention. The median CD4+ cell count was 10/mm3 (range, 3–400/mm3). Causative species were Candida albicans in nine episodes and Candida glabrata and Candida krusei in two episodes each. Eleven episodes occurred in 11 patients who had previously received fluconazole (mean total dose, 7.4 g), including the four episodes caused by non-albicans species. Outcome did not differ according to the administered antifungal therapy. CVCs were removed from seven patients (78%). The overall mortality was 38%. Candidemia is a potentially lethal nosocomial complication during late-stage AIDS and can be due to C. albicans and non-albicans strains. [ABSTRACT FROM PUBLISHER]

We report a case of aspergillus pericarditis with tamponade complicating invasive pulmonary aspergillosis in a patient treated for acute lymphocytic leukemia. Prolonged antifungal therapy and aggressive surgical treatment cured the pericarditis, without relapse, despite the fact that the patient underwent autologous bone marrow transplantation. In a review of 28 other cases of aspergillus pericarditis, we found that this condition usually had occurred in severely immunocompromised patients and was always the result of contiguous dissemination of Aspergillus from the lung or myocardium. Tamponade was present in eight of 29 patients. Aspergillus antigen was detected in the pericardial fluid of all three patients whose fluid specimens were tested. Aspergillus pericarditis was diagnosed before death in 10 of 29 patients, all of whom had established premortem diagnoses of invasive aspergillosis at other sites and had received antifungal therapy. Three of the four survivors received combined medical and aggressive surgical therapies. The performance of echocardiography early during the course of invasive pulmonary aspergillosis, together with intensive combined therapies, might lower the high mortality associated with aspergillus pericarditis. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented about scedosporium apiospermum lung infection with fatal subsequent postoperative outcome in an immunocompetent host.

The article presents a survey of pneumocystosis and dihydropteroate synthase genotype (DHPS) analysis in Parisian hospitals in France in 2003 and 2004. From January 1, 2003 to December 31, 2004, 313 Pneumocystis pneumonia cases were reported, 150 in 2003 and 163 in 2004. Sixty-five percent of the patients were HIV positive, where men represented 66% of the total patients. In addition, there was evidence that the prevalence of DHPS mutations depends on geographic locations.

An abstract of the article " In situ studies of protein aggregation kinetics with multiparametric and superresolution imaging" by Gabriele Kaminski Schierle and colleagues is presented.