Development of a Modular Biosensor System for Rapid Pathogen Detection

Progress in the field of pathogen detection relies on at least one of the following three qualities: selectivity, speed, and cost-effectiveness. Here, we demonstrate a proof of concept for an optical biosensing system for the detection of the opportunistic human pathogen Pseudomonas aeruginosa while addressing the abovementioned traits through a modular design. The biosensor detects pathogen-specific quorum sensing molecules and generates a fluorescence signal via an intracellular amplifier. Using a tailored measurement device built from low-cost components, the image analysis software detected the presence of P. aeruginosa in 42 min of incubation. Due to its modular design, individual components can be optimized or modified to specifically detect a variety of different pathogens. This biosensor system represents a successful integration of synthetic biology with software and hardware engineering

Robust Organizational Principles of Protrusive Biopolymer Networks in Migrating Living Cells

Cell migration is associated with the dynamic protrusion of a thin actin-based cytoskeletal extension at the cell front, which has been shown to consist of two different substructures, the leading lamellipodium and the subsequent lamellum. While the formation of the lamellipodium is increasingly well understood, organizational principles underlying the emergence of the lamellum are just beginning to be unraveled. We report here on a 1D mathematical model which describes the reaction-diffusion processes of a polarized actin network in steady state, and reproduces essential characteristics of the lamellipodium-lamellum system. We observe a steep gradient in filament lengths at the protruding edge, a local depolymerization maximum a few microns behind the edge, as well as a differential dominance of the network destabilizer ADF/cofilin and the stabilizer tropomyosin. We identify simple and robust organizational principles giving rise to the derived network characteristics, uncoupled from the specifics of any molecular implementation, and thus plausibly valid across cell types. An analysis of network length dependence on physico-chemical system parameters implies that to limit array treadmilling to cellular dimensions, network growth has to be truncated by mechanisms other than aging-induced depolymerization, e.g., by myosin-associated network dissociation at the transition to the cell body. Our work contributes to the analytical understanding of the cytoskeletal extension's bisection into lamellipodium and lamellum and sheds light on how cells organize their molecular machinery to achieve motility

Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Measurement of the ratios of branching fractions R(D∗)\mathcal{R}(D^{*}) and R(D0)\mathcal{R}(D^{0})

The ratios of branching fractions $\mathcal{R}(D^{*})\equiv\mathcal{B}(\bar{B}\to D^{*}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}\to D^{*}\mu^{-}\bar{\nu}_{\mu})$ and $\mathcal{R}(D^{0})\equiv\mathcal{B}(B^{-}\to D^{0}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(B^{-}\to D^{0}\mu^{-}\bar{\nu}_{\mu})$ are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb${ }^{-1}$ of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode $\tau^{-}\to\mu^{-}\nu_{\tau}\bar{\nu}_{\mu}$. The measured values are $\mathcal{R}(D^{*})=0.281\pm0.018\pm0.024$ and $\mathcal{R}(D^{0})=0.441\pm0.060\pm0.066$, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is $\rho=-0.43$. Results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb public pages

Gestion de la dotation des médecins correspondants du SAMU du réseau Nord-Alpin : difficultés et solutions

Introduction : « Médecins correspondants du SAMU » (MCSs) are links of the emergency chain in zones in more than 30 minutes of a SMUR. Theyhave a endowment of biomedical material and products of health. If the circuits of supply of this endowment are defined, the modalities of management by the practitioners are not specified. The objective is to estimate the difficulties of management met by the practitioners and to propose solutions of improvement.Data and method : Descriptive study by questionnaire with 130 MCSs of the network the Alpine North, to identify their organizations of management of their endowment, indicate the difficulties and evoke tracks of improvements.Results : 70 MCS answered, distributed in 46 offices. 35,7 % of the MCSs missed certain products of health during an intervention. The ketamine and the morphine are the most mentioned. 57,1 % of the MCSs report difficulties. The main reported difficulties are the resupplying of the endowment with reference hospitals, follow-up of the quantities and the lapsings of the products of health, as well as an insufficient endowment ketamine. The proposed solutions are the delegation to the staff not doctor, in particular the pharmacy ; the use of a software of management of the products of health and a quantity of ketamine more important.Conclusion: Difficulties exist in the management of the endowment MCSs by the practitioners, but improvements were already brought, others again are to be promoted to secure the therapeutic care on the ground and consolidate the membership of the doctors to the network MCSs.Introduction : Les Médecins Correspondants SAMU (MCS) sont des maillons de la chaîne d’urgence dans les zones à plus de 30 minutes d’un SMUR. Ils disposent d’une dotation de matériel biomédical et de produits de santé. Si les circuits d’approvisionnement de cette dotation sont définis, les modalités de gestion par les praticiens ne sont pas précisées. L'objectif est d’évaluer les difficultés de gestion rencontrées par les praticiens et de proposer des solutions d’amélioration.Matériels et méthode : Étude descriptive par questionnaire auprès des 130 MCS du réseau Nord-Alpin, pour identifier leurs organisations de gestion de leur dotation, indiquer les difficultés et évoquer des pistes d’améliorations.Résultats : 70 MCS ont répondu, répartis dans 46 cabinets. 35,7% des MCS ont manqué de certains produits de santé pendant une intervention. La kétamine et la morphine sont les plus mentionnés. 57,1% des MCS rapportent des difficultés. Les principales difficultés rapportées sont le réapprovisionnement de la dotation auprès des hôpitaux de référence, le suivi des quantités et des péremptions des produits de santé, ainsi qu’une dotation insuffisante en kétamine. Les solutions proposées sont la délégation à du personnel non médecin, notamment la pharmacie d’officine ; l'utilisation d'un logiciel de gestion des produits de santé et une quantité de kétamine plus importante.Conclusion : . Des difficultés existent dans la gestion de la dotation MCS par les praticiens, mais des améliorations ont déjà été apportées, d’autres sont encore à promouvoir pour sécuriser la prise en charge thérapeutique sur le terrain et conforter l’adhésion des médecins au réseau MCS

A new method for the calculation of continuous relaxation spectra from dynamic-mechanical data

We present a new method for the determination of highly precise continuous relaxation spectra. The method is based on the use of piecewise cubic Hermite splines, which are fairly easy to tabulate by using their knots. The Hermite splines method allows a continuous description of the spectrum by a series of polynomial functions. The numerical instabilities of the spectrum calculation are minimized by limiting the slope of the spectrum to physically meaningful values. The reproducibility of the spectrum calculation is within an error margin of about +/- 10% in the physically relevant relaxation time range. This method is able to retrieve the spectrum based on data calculated from a benchmark with high accuracy and precision

Pain assessment in rheumatology – How can we do better? A literature review

International audiencePatients’ symptoms have a place of prominence in the rheumatology landscape, and among them pain is the most conspicuous. Several pain assessment tools have been validated. One-dimensional pain scales such as visual analog scales (VASs) and numeric rating scales (NRSs) are fast to administer but have limitations that must be acknowledged. Some clinical situations require the use of multidimensional scales such as the McGill Pain Questionnaire or the Multidimensional Pain Inventory (MPI). These tools allow the assessment and management of the diverse components of pain. Here, we review the main patient-reported outcomes that can serve to evaluate pain and the psychometric properties of pain assessment tools. We also discuss the selection of the tool most appropriate for each situation (e.g., everyday practice and research)

Évaluer la douleur en rhumatologie – comment faire mieux ? Revue de la littérature

International audienceLa rhumatologie est une spécialité où l’on est confronté aux symptômes des patients, au premier rang desquels figure la douleur. Il existe plusieurs scores validés pour évaluer la douleur. Les échelles unidimensionnelles de la douleur, telles que l’échelle visuelle analogique ou l’échelle numérique simple sont rapides à réaliser mais présentent certaines limitations importantes à connaître. Certaines situations cliniques nécessitent l’emploi de questionnaires multidimensionnels, telles que le Questionnaire Saint-Antoine ou l’inventaire multidimensionnel de la douleur par exemple. L’ensemble des composantes de la douleur peut ainsi être évalué et prise en charge. Dans cet article, nous verrons les principaux critères rapportés par le patient permettant d’évaluer la douleur, et les propriétés psychométriques de ces questionnaires. Nous discuterons aussi du choix d’un questionnaire pour évaluer la douleur selon le cadre (pratique quotidienne, recherche)