A series of three studies were conducted to generate, develop, and validate the Attitudes toward Transgender Men and Women (ATTMW) scale. In Study 1, 120 American adults responded to an open-ended ...questionnaire probing various dimensions of their perceptions of transgender individuals and identity. Qualitative thematic analysis generated 200 items based on their responses. In Study 2, 238 American adults completed a questionnaire consisting of the generated items. Exploratory factor analysis (EFA) revealed two non-identical 12-item subscales (ATTM and ATTW) of the full 24-item scale. In Study 3, 150 undergraduate students completed a survey containing the ATTMW and a number of validity-testing variables. Confirmatory factor analysis (CFA) verified the single-factor structures of the ATTM and ATTW subscales, and the convergent, discriminant, predictive, and concurrent validities of the ATTMW were also established. Together, our results demonstrate that the ATTMW is a reliable and valid measure of attitudes toward transgender individuals.
Among aging-induced impairments, those affecting cognitive functions certainly represent one the most major challenge to face to improve elderly quality of life. In last decades, our knowledge on ...changes in the morphology and function of neuronal networks associated with normal and pathological brain aging has rapidly progressed, initiating the development of different pharmacological and behavioural strategies to alleviate cognitive aging. In particular, experimental evidences have accumulated indicating that the communication between neurons and its plasticity gradually weakens with aging. Because of its pivotal role for brain functional plasticity, the N-Methyl‑d-Aspartate receptor subtype of glutamate receptors (NMDAr) has gathered much of the experimental interest. NMDAr activation is regulated by many mechanisms. Among is the mandatory binding of a co-agonist, such as the amino acid d-serine, in order to activate NMDAr. This mini-review presents the most recent information indicating how d-serine could contribute to mechanisms of physiological cognitive aging and also considers the divergent views relative of the role of the NMDAr co-agonist in Alzheimer's disease.
•d-serine levels decrease in physiological aging.•In Alzheimer's disease, changes in d-serine levels remain unclear.•The direction of changes may depend on the stage of the disease.
The learning and memory deficits associated with non‐pathological ageing mainly result from alterations to the plasticity of neuronal network dynamics within the hippocampus. In addition to the broad ...spectrum of changes that affect the morphology and function of hippocampal excitatory circuits in the ageing brain, the impaired activation of the N‐methyl‐d‐aspartate subtype of glutamate receptors (NMDA‐R) is a typical feature, altering the induction and maintenance of long‐term potentiation, a major form of synaptic plasticity. In addition to glutamate, the binding of a co‐agonist at the strychnine‐insensitive glycine‐binding site is required for NMDA‐R activation. This review presents recent evidence that: (i) the amino acid d‐serine is an endogenous co‐agonist of synaptic NMDA‐R and necessary for long‐term potentiation expression, (ii) reduced d‐serine levels in the hippocampus contribute to synaptic plasticity and memory deficits in normal ageing, and (iii) age‐related oxidative stress selectively targets hippocampal serine racemase to impact d‐serine availability in neuronal networks. These results emphasize the critical role of the hippocampal d‐serine‐dependent pathway in changes affecting neuronal network dynamics in physiological ageing that underlie memory deficits. In addition, the central role of serine racemase in these changes opens new perspectives in the search for relevant therapeutic strategies aimed at reducing age‐related memory defects.
The learning and memory deficits associated with non pathological aging mainly result from alterations to the plasticity of neuronal network dynamics within the hippocampus. Besides the broad spectrum of changes that affect the morphology and function of hippocampal excitatory circuits in the aging brain, the impaired activation of the N‐methyl‐d‐aspartate subtype of glutamate receptors (NMDA‐R) by D‐serine is a typical feature, altering the induction and maintenance of long‐term potentiation (LTP), a major form of synaptic plasticity.
A theoretical study outlines the best strategies for identifying weakly interacting massive particles (WIMPs) in dark matter detectors. Over the past decades, several ideas and technologies have been ...developed to directly detect weakly interacting massive particles (WIMP) from the galactic halo. All these detection strategies share the common goal of discriminating a WIMP signal from the residual backgrounds. By directly detecting WIMPs, one can measure some or all of the observables associated to each nuclear recoil candidates, such as their energy and direction. In this study, we compare and examine the discovery potentials of each readout strategies from counting only (bubble chambers) to directional detectors (Time Projection Chambers) with 1d-, 2d-, and 3d-sensitivity. Using a profile likelihood analysis, we show that, in the case of a large and irreducible background contamination characterized by an energy distribution similar to the expected WIMP signal, directional information can improve the sensitivity of the experiment by several orders of magnitude. We also found that 1d directional detection is only less effective than a full 3d directional sensitivity by about a factor of 3, or 10 if we assume no sense recognition, still improving by a factor of 2 or more if only the energy of the events is being measured.
The future TESSERACT experiment will search for individual galactic DM particles below the proton mass through interactions with advanced, ultra-sensitive detectors. Currently TESSERACT is in a ...design phase aiming to produce fully defined detector technologies that will explore DM masses down to 10 MeV. It is designed to be sensitive to DM candidates interacting with the detector target material in producing both nuclear recoil DM (NRDM) and electron recoil (ERDM). To do so, multiple target materials will be used with varying detection strategies to ensure the capability to both actively reject the so-called low-energy excess and discriminate nuclear recoils against electron recoils. In addition to maximizing sensitivity to a variety of DM interactions, this provides an independent handle on instrumental backgrounds. Nowadays, the TESSERACT project encompasses two US-based technologies, namely HeRALD using superfluid helium as a target material, and SPICE using polar crystals (Al2O3 and SiO2) and scintillating crystals such as GaAs. In these proceedings, we discuss the recent proposal to host the future TESSERACT experiment at the Modane Underground Laboratory (LSM) and add a third French-based cryogenic semiconducting (Ge, Si) detector technology to the TESSERACT payload.
Abstract To gain insight into the contribution of d -serine to impaired cognitive aging, we compared the metabolic pathway and content of the amino acid as well as d -serine-dependent synaptic ...transmission and plasticity in the hippocampus of young and old rats of the Wistar and Lou/C/Jall strains. Wistar rats display cognitive impairments with aging that are not found in the latter strain, which is therefore considered a model of healthy aging. Both mRNA and protein levels of serine racemase, the d -serine synthesizing enzyme, were decreased in the hippocampus but not in the cerebral cortex or cerebellum of aged Wistar rats, whereas the expression of d -amino acid oxidase, which degrades the amino acid, was not affected. Consequently, hippocampal levels of endogenous d -serine were significantly lower. In contrast, serine racemase expression and d -serine levels were not altered in the hippocampus of aged Lou/C/Jall rats. Ex vivo electrophysiological recordings in hippocampal slices showed a marked reduction in N -methyl- d -aspartate-receptor (NMDA-R)-mediated synaptic potentials and theta-burst-induced long-term potentiation (LTP) in the CA1 area of aged Wistar rats, which were restored by exogenous d -serine. In contrast, NMDA-R activation, LTP induction and responses to d -serine were not altered in aged Lou/C/Jall rats. These results further strengthen the notion that the serine racemase-dependent pathway is a prime target of hippocampus-dependent cognitive deficits with aging. Understanding the processes that specifically affect serine racemase during aging could thus provide key insights into the treatment of memory deficits in the elderly.
Les nouvelles techniques génomiques révolutionnent le dépistage et le diagnostic anténatals, en permettant l’accès à des diagnostics d’affections foetales et/ou parentales dont la pénétrance n’est ...pas toujours complète. Ces techniques soulèvent de nombreuses questions, dans un contexte sensible, éthiquement différent du suivi postnatal. La création de groupes de réflexion multidisciplinaires nationaux et internationaux est fondamentale pour réfléchir aux diagnostics ou facteurs de susceptibilité importants à rapporter au couple en cours de grossesse.
There is a worldwide effort toward the development of a large time projection chamber devoted to directional dark matter detection. All current projects are being designed to fulfill a unique goal: ...identifying weakly interacting massive particle (WIMP) as such by taking advantage of the expected direction dependence of WIMP-induced events toward the constellation Cygnus. However, such proof of discovery requires a careful statistical data treatment. In this paper, the discovery potential of forthcoming directional detectors is addressed by using a frequentist approach based on the profile likelihood ratio test statistic. This allows us to estimate the expected significance of a dark matter detection taking into account astrophysical and experimental uncertainties. We show that the energy threshold and the background contamination are key experimental issues for directional detection, while angular resolution and sense recognition efficiency only mildly affect the sensitivity and the energy resolution is unimportant. This way, we found that a 30 kg.year CF sub(4) directional experiment could reach a 3sigma sensitivity at 90% C.L. down to 10 super(-5) pb and 3.10 super(-4) pb for the WIMP-proton axial cross section in the most optimistic and pessimistic detector performance case, respectively.
Cosmological observations indicate that most of the matter in the Universe is Dark Matter. Dark Matter in the form of Weakly Interacting Massive Particles (WIMPs) can be detected directly, via its ...elastic scattering off target nuclei. Most current direct detection experiments only measure the energy of the recoiling nuclei. However, directional detection experiments are sensitive to the direction of the nuclear recoil as well. Due to the Sun’s motion with respect to the Galactic rest frame, the directional recoil rate has a dipole feature, peaking around the direction of the Solar motion. This provides a powerful tool for demonstrating the Galactic origin of nuclear recoils and hence unambiguously detecting Dark Matter. Furthermore, the directional recoil distribution depends on the WIMP mass, scattering cross section and local velocity distribution. Therefore, with a large number of recoil events it will be possible to study the physics of Dark Matter in terms of particle and astrophysical properties. We review the potential of directional detectors for detecting and characterizing WIMPs.
The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting ...massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^{2}.
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