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The article describes the commissioning and technical development of the Weak Interaction Studies with 32Ar Decay (WISArD) experiment, installed at the radioactive ion-beam facility ISOLDE/CERN. The experiment aims to extend the present limits on scalar and tensor currents in the weak interaction and hence search for physics beyond the Standard Model. The evaluation of these limits relies on measuring the proton energy in beta-delayed proton emission, sensitive to both the beta-neutrino angular correlation coefficient aβν and the Fierz interference term b. The method tries to improve previous studies by considering the positron-proton coincidences when determining the kinematic shift in the energy of the emitted protons. Using this coincidence technique, the aβν and b coefficients will be measured at the per mil level. Simulations were employed to optimize the ion beam transport efficiency and validate proof-of-principle results obtained in November 2018 (Nov2018). Upgrades are ongoing, and we are looking into improvements to the overall performance of the setup.

Neutron-induced reaction cross sections of unstable nuclei are essential for understanding the synthesis of heavy elements in stars and for applications in nuclear technology. However, their measurement is very complicated due to the radioactivity of the targets involved. We propose to circumvent this problem by using the surrogate reaction method in inverse kinematics, where the nucleus formed in the neutron- induced reaction of interest is produced by a reaction involving a radioactive heavy-ion beam and a stable, light target nucleus. The probabilities as a function of the compound-nucleus excitation energy for γ-ray emission, neutron emission and fission, which can be measured with the surrogate reaction, are particularly useful to constrain model parameters and to obtain more accurate predictions of the neutron-induced reaction cross sections of interest. Yet, the full development of the surrogate method is hampered by numerous long- standing target issues, which can be solved by combining surrogate reactions with the unique and largely unexplored possibilities at heavy-ion storage rings. In this contribution, we describe the developments we are carrying out to measure for the first time simultaneously γ-ray emission, neutron emission and fission probabilities at the storage rings of the GSI/FAIR facility. In particular, we will present the first results of the proof of principle experiment, which we performed in June 2022 at the Experimental Storage Ring (ESR) of GSI/FAIR.

International audience; An experiment was conducted at the GANIL/LISE3 facility to produce the 10+ isomer of 54Ni and measure its proton radioactivity decay branches. The proton detection was achieved with the ACTAR TPC device that enabled the separation of the small signal of the emitted proton from the large signal of the implanted ion, while the decay half-life is of the order of 150 ns. From the measured data, the emitted proton track length and the decay time of the ion can be extracted simultaneously. The full proton radioactivity pattern could be established, with two emission branches and their relative branching ratio. Data processing and analysis that allowed to identify and separate the ion and the proton signals in order to reconstruct the particles trajectories and decay time are detailed. The evaluation of the detection efficiency for the proton radioactivity branches based on a full simulation is described.

International audience; Proton-emission branches of the 10+ isomer in the Tz=−1 nucleus 54Ni have been imaged with the active target and time projection chamber (ACTAR TPC) in an experiment conducted at the Grand Accélérateur National d'Ions Lourds (GANIL). The completed decay scheme allows derivation of the reduced transition strengths, B(E2;10+→8+) and B(E4;10+→6+), for the two competing γ-ray transitions. By means of a comparison with their well-known ‘mirror transitions’ in Tz=+154Fe, and aided by a variety of shell-model calculations in the fp model space, effective charges for E4 transitions near N=Z56Ni can be deduced: επ≈1.40 and εν≈0.30. Mirror-energy differences are explored with various shell-model interactions and isospin-symmetry breaking terms.

We report here the results of a study of the $\beta$ decay of the proton-rich Ge isotopes, $^{60}$Ge and $^{62}$Ge, produced in an experiment at the RIKEN Nishina Center. We have improved our knowledge of the half-lives of $^{62}$Ge (73.5(1) ms), $^{60}$Ge (25.0(3) ms) and its daughter nucleus, $^{60}$Ga (69.4(2) ms). We measured individual $\beta$-delayed proton and $\gamma$ emissions and their related branching ratios. Decay schemes and absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. A total $\beta$-delayed proton-emission branching ratio of 67(3)% has been obtained for $^{60}$Ge. New information has been obtained on the energy levels populated in $^{60}$Ga and on the 1/2$^-$ excited state in the $\beta p$ daughter $^{59}$Zn. We extracted a ground state to ground state feeding of 85.3(3)% for the decay of $^{62}$Ge. Eight new $\gamma$ lines have been added to the de-excitation of levels populated in the $^{62}$Ga daughter.

Proton radioactivity was discovered exactly 50 years ago. First, this nuclear decay mode sets the limit of existence on the nuclear landscape on the neutron-deficient side. Second, it comprises fundamental aspects of both quantum tunnelling as well as the coupling of (quasi)bound quantum states with the continuum in mesoscopic systems such as the atomic nucleus. Theoretical approaches can start either from bound-state nuclear shell-model theory or from resonance scattering. Thus, proton-radioactivity guides merging these types of theoretical approaches, which is of broader relevance for any few-body quantum system. Here, we report experimental measurements of proton-emission branches from an isomeric state in

We report first time measurements of the beta-neutrino angular correlation based on the kinetic energy shift of protons emitted in parallel or anti-parallel directions with respect to the positron in the beta decay of $^{32}$Ar. This proof of principle experiment provided simultaneous measurements for the superallowed 0$^+$~$\rightarrow$~0$^+$ transition followed by a 3356~keV proton emission and for a Gamow-Teller transition followed by a 2123~keV proton emission. The results, respectively ${\tilde a_{\beta\nu}}=1.01(3)_{(stat)}(2)_{(syst)}$ and ${\tilde a_{\beta\nu}}=-0.22(9)_{(stat)}(2)_{(syst)}$, are found in agreement with the Standard Model. A careful analysis of the data shows that future measurements can reach a precision level of 10$^{-3}$ for both pure Fermi and pure Gamow-Teller decay channels, providing new constraints on both scalar and tensor weak interactions.

Accurate mass measurements of neutron-rich iron and cobalt isotopes $^{67}\mathrm{Fe}$ and $^{69,70}\mathrm{Co}$ have been realized with the JYFLTRAP double Penning-trap mass spectrometer. With novel ion-manipulation techniques, the masses of the $^{69,70}\mathrm{Co}$ ground states and the $1/{2}^{\ensuremath{-}}$ isomer in $^{69}\mathrm{Co}$ have been extracted for the first time. The measurements remove ambiguities in the previous mass values and yield a smoother trend on the mass surface, extending it beyond $N=40$. The moderate $N=40$ subshell gap has been found to weaken below $^{68}\mathrm{Ni}$, a region known for shape coexistence and increased collectivity. The excitation energy for the $1/{2}^{\ensuremath{-}}$ intruder state in $^{69}\mathrm{Co}$ has been determined for the first time and is compared to large-scale shell-model calculations. The new mass values also reduce significantly mass-related uncertainties for the astrophysical rapid neutron-capture process calculations.

Traumatic abrasions on human extremities as a result of direct contact with sea, lake, river, or aquarium animals or from traumatic injuries sustained in seawater may develop into solitary or linear granulomatous lesions. One of the more common microbial etiologies for such infections is Mycobacterium marinum. An astute pediatrician, family physician, or nurse practitioner should have a high index of suspicion and obtain specific cultures to support the growth of Mycobacterium species. Mycobacterium marinum infections will not respond to antibiotics typically chosen to treat simple skin and soft tissue infections. Rather, M. marinum infections are best treated by prolonged antimicrobial treatment regimens for 3 to 6 months and, in some cases, may require polypharmacologic therapy. We present the case of a 6-year-old girl who suffered a traumatic abrasion on her right ankle in seawater. For 10 days, the skin infection morphed from cellulitis, papules, pustules, and eventually into sporotrichoid linear granuloma. After several failed antibiotic trials, M. marinum was eventually identified from the depth of her lesions. The patient improved after a 3-month course of clarithromycin. This case report is the first to include pictures demonstrating the clinical progression and resolution of M. marinum infection.

In "An Answer to the Question: What is Enlightenment?", the eighteenth-century German philosopher Immanuel Kant responded to a big question buried in a little footnote. But you wouldn't know it, because contemporary editions of Kant's famous essay no longer reproduce the parenthetical directive that Kant's original essay printed right under the essay's title in the December issue of the Berlinische Monatsschrift in 1784: "S. Decemb. 1783. S. 516." (See December 1783, p. 516). And, in fact, page 516 in the December volume of the Berlinische Monatsschrift 1783 has a footnote: "What is Enlightenment? This question is nearly as important as: what is truth? And should certainly be answered before one starts to enlighten! But I have yet to find it answered anywhere."

Mass measurements of $^{49}$Sc, $^{50}$Sc, $^{70}$As, $^{73}$Br and stable $^{196}$Hg nuclides produced at CERN's radioactive-ion beam facility ISOLDE are presented. The measurements were performed at the ISOLTRAP mass spectrometer by use of the multi-reflection time-of-flight and the Penning-trap mass spectrometry techniques. The new results agree well with previously known literature values. The mass accuracy for all cases has been improved. Mass measurements of $^{49,50}$Sc, $^{70}$As, $^{73}$Br and $^{196}$Hg nuclides produced at CERN's radioactive-ion beam facility ISOLDE are presented. The measurements were performed at the ISOLTRAP mass spectrometer by use of the multi-reflection time-of-flight and the Penning-trap mass spectrometry techniques. The new results agree well with previously known literature values. The mass accuracy for all cases has been improved.

International audience; We report on the observation of 67Kr that has been produced in an experiment performed at the RIKEN/BigRIPS facility. The two-proton decay of 67Kr has been evidenced and this nucleus is thus the fourth observed long lived ground-state two-proton emitter, after 45Fe, 48Ni and 54Zn. In addition, the decay of several isotopes in the mass region has been investigated. While for previous cases of two-proton radioactivity, the theoretical models could reproduce the measured data, this is not the case anymore for 67Kr. Two interpretations have been proposed to explain this discrepancy: a transition between real two-proton and sequential decay or the influence of deformation. These hypotheses will be tested in future experiments by measuring the angular and energy correlations of the emitted protons.

Expérience GANIL; International audience; A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and gamma-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived on-line sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed beta decays for tests of the weak-interaction standard model.

D-Bifunctional protein deficiency, caused by recessive mutations in HSD17B4, is a severe disorder of peroxisomal fatty acid oxidation. Nonspecific clinical features may contribute to diagnostic challenges. We describe a newborn female with infantile-onset seizures and nonspecific mild dysmorphisms who underwent extensive genetic workup that resulted in the detection of a novel homozygous mutation (c.302+1_4delGTGA) in the HSD17B4 gene, consistent with a diagnosis of D-bifunctional protein deficiency. By comparing the standard clinical workup to diagnostic analysis performed through research-based whole-genome sequencing (WGS), which independently identified the causative mutation, we demonstrated the ability of genomic sequencing to serve as a timely and cost-effective diagnostic tool for the molecular diagnosis of apparent and occult newborn diseases. As genomic sequencing becomes more available and affordable, we anticipate that WGS and related omics technologies will eventually replace the traditional tiered approach to newborn diagnostic workup.

The $\beta$ decay of the odd-odd nucleus $^{70}$Br has been investigated with the BigRIPS and EURICA setups at the Radioactive Ion Beam Factory (RIBF) of the RIKEN Nishina Center. The $T=0$ ($J^{\pi}=9^+$) and $T=1$ ($J^{\pi}=0^+$) isomers have both been produced in in-flight fragmentation of $^{78}$Kr with ratios of 41.6(8)\% and 58.4(8)\%, respectively. A half-life of $t_{1/2}=2157^{+53}_{-49}$ ms has been measured for the $J^{\pi}=9^+$ isomer from $\gamma$-ray time decay analysis. Based on this result, we provide a new value of the half-life for the $J^{\pi}=0^+$ ground state of $^{70}$Br, $t_{1/2}=78.42\pm0.51$ ms, which is slightly more precise, and in excellent agreement, with the best measurement reported hitherto in the literature. For this decay, we provide the first estimate of the total branching fraction decaying through the $2^+_1$ state in the daughter nucleus $^{70}$Se, $R(2^+_1)=1.3\pm1.1\%$. We also report four new low-intensity $\gamma$-ray transitions at 661, 1103, 1561, and 1749 keV following the $\beta$ decay of the $J^{\pi}=9^+$ isomer. Based on their coincidence relationships, we tentatively propose two new excited states at 3945 and 4752 keV in $^{70}$Se with most probable spins and parities of $J^{\pi}=(6^+)$ and $(8^+)$, respectively. The observed structure is interpreted with the help of shell-model calculations, which predict a complex interplay between oblate and prolate configurations at low excitation energies.

We have measured the $ \beta$ -decay half-lives of 16 neutron-deficient nuclei with $ T_{z} = -1/2$ and -1 , ranging from chromium to germanium. They were produced in an experiment carried out at GANIL and optimized for the production of$^{58}$Zn , for which in addition we present the decay scheme and absolute Fermi and Gamow-Teller transition strengths. Since all of these nuclei lie on the rp -process pathway, the $ T_{1/2}$ values are important ingredients for the rp -process reaction flow calculations and for models of X-ray bursters.

This paper concerns the experimental study of the β decay properties of few proton-rich fp -shell nuclei. The nuclei were produced at GANIL in fragmentation reactions, separated with the LISE spectrometer and stopped in an implantation detector surrounded by Ge detectors. The β -delayed gammas, β -delayed protons and the exotic β -delayed gamma-proton emission have been studied. Preliminary results are presented. The decay of the T z = − 2 nucleus 56 Zn has been studied in detail. Information from the β -delayed protons and β -delayed gammas has been used to deduce the decay scheme. The exotic beta-delayed gamma-proton decay has been observed for the first time in the fp -shell. The interpretation of the data was made possible thanks to the detailed knowledge of the mirror Charge Exchange (CE) process and the gamma de-excitation of the states in 56 Co, the mirror nucleus of 56 Cu.

We report the first observation of the ${2}^{+}$ isomer in $^{52}\mathrm{Co}$, produced in the $\ensuremath{\beta}$ decay of the ${0}^{+}$, $^{52}\mathrm{Ni}$ ground state. We have observed three $\ensuremath{\gamma}$ rays at 849, 1910, and 5185 keV characterizing the $\ensuremath{\beta}$ de-excitation of the isomer. We have measured a half-life of 102(6) ms for the isomeric state. The Fermi and Gamow-Teller transition strengths for the $\ensuremath{\beta}$ decay of $^{52m}\mathrm{Co}$ to $^{52}\mathrm{Fe}$ have been determined. We also add new information on the $\ensuremath{\beta}$ decay of the ${6}^{+}$, $^{52}\mathrm{Co}$ ground state, for which we have measured a half-life of 112(3) ms.

In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from 67Kr. At the same time, no evidence for 2p emission of 59Ge and 63Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to 67Kr as being the best new candidate among the three for two-proton radioactivity. 67Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of 67Kr is 7.4(30) ms.

The results of a study of the $\ensuremath{\beta}$ decays of three proton-rich nuclei with ${T}_{z}=\ensuremath{-}2$, namely $^{48}\mathrm{Fe},^{52}\mathrm{Ni}$, and $^{56}\mathrm{Zn}$, produced in an experiment carried out at GANIL, are reported. In all three cases we have extracted the half-lives and the total $\ensuremath{\beta}$-delayed proton emission branching ratios. We have measured the individual $\ensuremath{\beta}$-delayed protons and $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$ rays and the branching ratios of the corresponding levels. Decay schemes have been determined for the three nuclei, and new energy levels are identified in the daughter nuclei. Competition between $\ensuremath{\beta}$-delayed protons and $\ensuremath{\gamma}$ rays is observed in the de-excitation of the $T=2$ isobaric analog states in all three cases. Absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. In addition, we discuss in detail the data analysis taking as a test case $^{56}\mathrm{Zn}$, where the exotic $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-proton decay has been observed.

Inhaled corticosteroids (ICS) are drugs of choice for persistent asthma. Less than 500 µg/d of fluticasone are believed to be safe. We found 92 cases of adrenal suppression in PubMed; among these cases there were 13 children who took 500 µg/d or less of fluticasone. Adrenal insufficiency was diagnosed in a 7-year-old boy on 460 µg ICS for 16 months, with a diagnosis of chronic persistent asthma. A random cortisol was nondetectable as was an early morning cortisol. ICS have greatly improved the day-to-day lives of children with chronic persistent asthma. Parents of children younger than 12 years, who use at least 400 µg of inhaled fluticasone (or bioequivalent), must be given oral and written instructions about warning symptoms of hypocortisolism. Major stress such as surgery, gastrointestinal, bronchopulmonary, or other systemic infections, and heat stress may mandate a written plan of action for use by hospital physicians.

Developing collection-level surveys to expose hidden collections in special collections and archives departments within ARL libraries has received a great deal of scholarly attention in the recent years. Numerous standards have been explored, and each has its strengths and weaknesses. This paper summarizes some of the major initiatives in collection-level surveys, descriptions, and preliminary records. A comparison of metadata structures is used to build a preliminary record model that provides a standard description that is easily adapted to various institutions and all formats. This preliminary record model is applied to special collections materials at the University of Colorado at Boulder as a test case, and further areas of research are discussed.

Masses adjacent to the classical waiting-point nuclide ^{130}Cd have been measured by using the Penning-trap spectrometer ISOLTRAP at ISOLDE/CERN. We find a significant deviation of over 400 keV from earlier values evaluated by using nuclear beta-decay data. The new measurements show the reduction of the N=82 shell gap below the doubly magic ^{132}Sn. The nucleosynthesis associated with the ejected wind from type-II supernovae as well as from compact object binary mergers is studied, by using state-of-the-art hydrodynamic simulations. We find a consistent and direct impact of the newly measured masses on the calculated abundances in the A=128-132 region and a reduction of the uncertainties from the precision mass input data.

Much of traditional book cataloging is influenced by a touch-it-once mentality, where work is completed in as few steps as possible. By avoiding unnecessary revision, libraries can process materials quickly and benefit from economies of scale. Valuable staff time is preserved to process additional materials. However, the touch-it-once mentality is problematic when dealing with special collections materials, since they often differ between manifestations and are primary sources for research that informs their description. This paper discusses the idea of “progressive bibliography,” or proceeding from minimal to fuller descriptions, as an intellectually valid and pragmatically essential methodology. It examines some already . . .

D-Bifunctional protein deficiency, caused by recessive mutations in HSD17B4, is a severe disorder of peroxisomal fatty acid oxidation. Nonspecific clinical features may contribute to diagnostic challenges. We describe a newborn female with infantile-onset seizures and nonspecific mild dysmorphisms who underwent extensive genetic workup that resulted in the detection of a novel homozygous mutation (c.302+1_4delGTGA) in the HSD17B4 gene, consistent with a diagnosis of D-bifunctional protein deficiency. By comparing the standard clinical workup to diagnostic analysis performed through research-based whole-genome sequencing (WGS), which independently identified the causative mutation, we demonstrated the ability of genomic sequencing to serve as a timely and cost-effective diagnostic tool for the molecular diagnosis of apparent and occult newborn diseases. As genomic sequencing becomes more available and affordable, we anticipate that WGS and related omics technologies will eventually replace the traditional tiered approach to newborn diagnostic workup.

The recently confirmed neutron-shell closure at $N=32$ has been investigated for the first time below the magic proton number $Z=20$ with mass measurements of the exotic isotopes $^{52,53}\mathrm{K}$, the latter being the shortest-lived nuclide investigated at the online mass spectrometer ISOLTRAP. The resulting two-neutron separation energies reveal a 3 MeV shell gap at $N=32$, slightly lower than for $^{52}\mathrm{Ca}$, highlighting the doubly magic nature of this nuclide. Skyrme-Hartree-Fock-Bogoliubov and ab initio Gorkov-Green function calculations are challenged by the new measurements but reproduce qualitatively the observed shell effect.

The recently confirmed neutron-shell closure at N=32 has been investigated for the first time below the magic proton number Z=20 with mass measurements of the exotic isotopes (52,53)K, the latter being the shortest-lived nuclide investigated at the online mass spectrometer ISOLTRAP. The resulting two-neutron separation energies reveal a 3 MeV shell gap at N=32, slightly lower than for 52Ca, highlighting the doubly magic nature of this nuclide. Skyrme-Hartree-Fock-Bogoliubov and ab initio Gorkov-Green function calculations are challenged by the new measurements but reproduce qualitatively the observed shell effect.

The excitatory postsynaptic currents (EPSCs) evoked in Purkinje cells (PCs) by stimulating parallel fibres (PFs) usually show a single peak, but EPSCs with multiple peaks (polyphasic EPSCs) can be observed in slices from animals older than 15 days. The EPSCs remain polyphasic when the postsynaptic current is reduced (either by reducing the intensity of the PF stimulation or by adding AMPA receptor antagonists) and when the PC membrane potential is made positive. Thus the late peaks are not due to postsynaptic active currents generated in the imperfectly clamped PC, and must arise from repetitive action potentials in the PF. Extracellular recordings from granule cell (GC) somata showed that a single PF stimulation can elicit a doublet or a train of action potentials. Both the late action potentials recorded in the GCs and the late peaks of the polyphasic EPSCs recorded in the PCs were reduced or abolished by paired-pulse stimulation of the PF or by bath application of the GABA(A) agonist muscimol. The late action potentials in the GCs were also suppressed by local application of muscimol around the cell body. We propose that after a single stimulation of a PF, the antidromic invasion of the ascending axon and the granule cell can trigger a doublet or a burst of action potentials which back-propagate into the PF (except for the first, which finds the PF still in its refractory period). The repetitive activation of the PF by a single stimulation could play a role in the induction of long-term depression.

Eikenella corrodens is a part of normal human oral flora and a rare cause of intrauterine and neonatal infections. We describe a case of congenital E. corrodens sepsis with positive blood cultures at birth in the setting of low maternal risk factors for infection. Our case is one of two reported cases of congenital E. corrodens sepsis resulting in newborn survival.

At the cerebellar synapses between parallel fibers (PFs) and Purkinje cells (PCs), long-term depression (LTD) of the excitatory synaptic current has been assumed to be independent of the N-methyl-D-aspartate (NMDA) receptor activation because PCs lack NMDA receptors. However, we now report that LTD is suppressed by NMDA receptor antagonists that act on presynaptic NMDA receptors of the PFs. This effect is still observed when the input is restricted to a single fiber. Therefore, LTD does not require the spatial integration of multiple inputs. In contrast, it involves a temporal integration, since reliable LTD induction requires the PFs to fire two action potentials in close succession. This implies that LTD will selectively depress the response to a burst of presynaptic action potentials.

We report the observation of a very exotic decay mode at the proton drip line, the $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-proton decay, clearly seen in the $\ensuremath{\beta}$ decay of the ${T}_{z}=\ensuremath{-}2$ nucleus $^{56}\mathrm{Zn}$. Three $\ensuremath{\gamma}$-proton sequences have been observed after the $\ensuremath{\beta}$ decay. Here this decay mode, already observed in the $sd$ shell, is seen for the first time in the $fp$ shell. Both $\ensuremath{\gamma}$ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.

We report the observation of a very exotic decay mode at the proton drip line, the β-delayed γ-proton decay, clearly seen in the β decay of the T_{z}=-2 nucleus ^{56}Zn. Three γ-proton sequences have been observed after the β decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the fp shell. Both γ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.

Presynaptic receptors were discovered sixty years ago. Their main function is to modulate transmitter release. They can be separated into ionotropic and metabotropic receptors. Presynaptic ionotropic receptors open ion channels in the presynaptic terminals. Presynaptic metabotropic receptors modulate ion channels, and can also modulate transmitter release by acting on the release machinery. The molecules that activate presynaptic receptors on a given terminal can originate from the same presynaptic terminal, from neighbouring ones, but also from the postsynaptic target, from neighbouring glial cells and from distant sources.

Previous studies of the accuracy of rapid in-office tests for group A Streptococcus had disparate results, ranging from sensitivity of 70% to more than 90%. The sensitivity and specificity of 3 commercially available Strep A tests were determined in 2 private pediatric office settings. Acceava Strep A, Genzyme OSOM Strep A, and the Quidel QuickVue Strep A tests were the representative rapid tests for detection of Streptococcus pyogenes. Overnight culture on standard 5% sheep blood agar was the reference standard for this study. All 3 CLIA (Clinical Laboratory Improvement Amendments)-waived tests had sensitivities and specificities that exceeded 95%.

1 Two classes of amphiphilic compounds, lysophospholipids and arachidonic acid, have been suggested to produce opposite deformations of the lipid bilayer. We have found that their effects on N-methyl-D-aspartate (NMDA) responses are opposite, and resemble those of mechanical deformations of the plasma membrane. 2 Lysophospholipids inhibited NMDA responses both in nucleated patches taken from cultured neurons and in cells expressing recombinant NMDA receptors. This inhibition was reversible, voltage independent and stronger at non-saturating doses of agonist. It was not linked to the charge of the polar head, and was not mimicked by lysophosphatidic acid or phosphatidylcholine. In outside-out patches, lysophospholipids reduced the open probability of NMDA-activated channels without changing their single-channel conductance. 3 The inhibition produced by lysophospholipids occluded that produced by a mechanical compression induced by changes in osmotic or hydrostatic pressure. 4 The potentiation of NMDA responses by arachidonic acid was observed both in native and recombinant receptors, including those in which the putative ‘fatty acid binding domain’ had been deleted. This suggests that, like lysophospholipids, arachidonic acid alters the NMDA receptor by insertion into the lipid bilayer. 5 Recombinant receptors in which the cytoplasmic tails had been modified or deleted were still sensitive to mechanical deformation. A linkage to the cytoskeleton is therefore not required for NMDA receptor mechanosensitivity. 6 The fact that the NMDA responses are depressed similarly by compression and lysophospholipids, and potentiated similarly by stretch and arachidonic acid supports the notion that the modulation of NMDA receptor activity by asymmetrical amphiphilic compounds involves pressure changes transmitted through the lipid bilayer. Compounds with a large hydrophilic head mimic the effects of a compression, and compounds with a small hydrophilic head mimic the effects of stretch.

Micromolar concentrations of extracellular Zn2+are known to antagonize native NMDA receptors via a dual mechanism involving both a voltage-independent and a voltage-dependent inhibition. We have tried to evaluate the relative importance of these two effects and their subunit specificity on recombinant NMDA receptors expressed in HEK 293 cells andXenopusoocytes. The comparison of NR1a–NR2A and NR1a–NR2B receptors shows that the voltage-dependent inhibition is similar in both types of receptors but that the voltage-independent inhibition occurs at much lower Zn2+concentrations in NR1a–NR2A receptors (IC50in the nanomolar range) than in NR1a–NR2B receptors (IC50in the micromolar range). The high affinity of the effect observed with NR1a–NR2A receptors was found to be attributable mostly to the slow dissociation of Zn2+from its binding site. By analyzing the effects of Zn2+on varied combinations of NR1 (NR1a or NR1b) and NR2 (NR2A, NR2B, NR2C), we show that both the NR1 and the NR2 subunits contribute to the voltage-independent Zn2+inhibition. We have observed further that under control conditions, i.e., in zero nominal Zn2+solutions, the addition of low concentrations of heavy metal chelators markedly potentiates the responses of NR1a–NR2A receptors, but not of NR1a–NR2B receptors. This result suggests that traces of a heavy metal (probably Zn2+) contaminate standard solutions and tonically inhibit NR1a–NR2A receptors. Chelation of a contaminant metal also could account for the rapid NR2A subunit-specific potentiations produced by reducing compounds like DTT or glutathione.

We report a strong coupling between permeation and gating in a mutant NMDA channel (NR1 N598Q-NR2A). The channel opens to two states that differ by their conductance and, surprisingly, by their selectivity for two permeant monovalent cations, Na+ and Cs+. The two open states are linked to the closed state via a cyclic gating reaction that proceeds preferentially in one direction under biionic conditions, indicating that the gating mechanism is not at equilibrium. The direction and the magnitude of this gating asymmetry can be accounted for by assuming that ions bound to a site in the permeation pathway influence the gating of this mutant channel, and that in the closed state, the channel site is accessible to internal cations.

Mg2+ ions block N-methyl-D-aspartate (NMDA) channels by entering the pore from either the extracellular or the cytoplasmic side of the membrane in a voltage-dependent manner. We have used these two different block phenomena to probe the structure of the subunits forming NMDA channels. We have made several amino acid substitutions downstream of the Q/R/N site in the TMII region of both NR1 and NR2A subunits. Mutant NR1 subunits were coexpressed with wild-type NR2A subunits and vice versa in Xenopus oocytes. We found that individually mutating the first two amino acid residues downstream to the Q/R/N site affects mostly the block by external Mg2+. Mutations of residues five to seven positions downstream of the Q/R/N site do not influence the external Mg2+ block, but clearly influence the block by internal Mg2+. These data add support to the hypothesis that there are two separate binding sites for external and internal Mg2+ block. They also indicate that the C-terminal end of TMII contributes to the inner vestibule of the pore of NMDA channels and thus provide additional evidence that TMII forms a loop that reemerges toward the cytoplasmic side of the membrane.

OBJECTIVE: To evaluate whether pediatric patients infected with human immunodeficiency virus (HIV) can mount appropriate delayed–type hypersensitivity (DTH) skin responses to recall antigens and whether these responses can be correlated with clinical or immunologic parameters. DESIGN: Prospective evaluation of DTH responses in HIV-infected children. Uninfected children born to HIV-infected mothers served as control subjects. Antigens used for yearly DTH testing included Candida albicans (1:100, 1:10); mumps virus; Trichophyton; purified protein derivative of tuberculin; and tetanus toxoid (1:100, 1:10). At the time of each DTH test, patients were staged according to two Centers for Disease Control and Prevention pediatric HIV classification systems, and T-cell subsets were obtained. RESULTS: Twenty-seven HIV-infected patients with a median age at entry of 74.1 (range, 12 to 156) months were followed. Forty-four DTH skin tests in 21 symptom-free HIV-infected patients (P1) and 18 tests in 10 HIV-infected patients with symptoms (P2), as well as 43 DTH skin tests in 18 patients who had either mild or moderate clinical symptoms or immunosuppression and 19 tests in 13 patients with severe symptoms or immunosuppression, were evaluated. Sixteen DTH skin tests were performed in 14 uninfected patients. HIV-infected patients tended to have fewer DTH responses to antigens and of smaller size than did uninfected patients. When controlled for age, few differences in DTH responsiveness were seen between HIV-infected and uninfected patients. Anergy was associated with symptomatic disease, evidence of advanced clinical or immunologic disease, and low CD4 + percentages ( p CONCLUSIONS: HIV-infected children are able to mount antigen-specific cell-mediated immune responses that are qualitatively similar to those of age-matched control subjects. Loss of DTH responsiveness correlates with both clinical and immunologic evidence of HIV disease progression. (J P EDIATR 1996;129:245-50)

Extracellular Mg2+, which blocks NMDA channels in a voltage-dependent manner and increases the receptor's affinity for glycine, is shown here to potentiate NMDA responses at saturating glycine concentrations. This potentiation, induced by millimolar concentrations of Mg2+, is not mimicked by Ca2+ and Ba2+ and is voltage independent. The potentiation is variable in native receptors of cultured mouse central neurons; in recombinant receptors, it is “permitted” by the NR2B subunit and prevented by the NR1 splice variant containing an N-terminal insert. Mg2+ also induces a shift of the pH sensitivity of NMDA receptors. The similarity and nonadditivity of the effects of Mg2+ and spermine suggest that Mg2+ may be the physiological agonist acting at the subunit-specific spermine site.

The half-lives of the Tz = -2, 56Zn and Tz = -1, 58Zn isotopes and other nuclei were measured in a {\beta}-decay experiment at GANIL. The energy levels populated by the 56Zn {\beta} decay were determined. The 56Zn results are compared with the results of the mirror process, the charge exchange reaction 56Fe(3He,t)56Co.

Changes in osmotic and hydrostatic pressure were found to modulate NMDA responses of cultured embryonic mouse neurons recorded in various patch-clamp configurations. In nucleated patches, NMDA currents were potentiated by reductions in external osmolarity and were reduced in hyper-osmotic solutions. These changes, which were greater for low concentrations of NMDA, were not observed for responses to kainate, glycine, or GABA. They could be mimicked by directly changing the pipette pressure in nucleated, outside-out, inside-out, and cell-attached patches. Osmosensitivity of NMDA responses was also observed in the whole-cell mode, but only after prolonged dialysis. Mechanosensitivity of NMDA receptors could have an important role in neuronal regions experiencing changes in membrane tension, such as spines or growth cones.

International audience; Studies of -delayed emission of protons for 43Cr and 51Ni were performed with a Time Projection Chamber. This detection setup allows to reconstruct in the three-dimensional space the tracks of the protons emitted. For the first time, -delayed emission of two protons is directly observed for 43Cr and 51Ni. The question about correlations between protons can be accessed. Finally, we show that 43Cr can emit up to three delayed protons.