Post-traumatic stress disorder: review of DSM criteria and functional neuroanatomy

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for post-traumatic stress disorder (PTSD) consist of over twenty possible symptoms that can be divided into six broad categories. These categories correlate with specific brain networks that regulate emotions, behaviors, and autonomic function. Normal functioning of these networks depends on two key regions; the prefrontal cortex and the amygdala. The prefrontal cortex provides top-down executive control over amygdala, whereas the amygdala is critical for threat detection and activation of the ‘fight or flight’ response. Events that trigger extreme and/or prolonged fear can cause persisting dysregulation within the prefrontal-amygdala circuit; resulting in PTSD symptomatology. Studies indicate that effective treatment of PTSD, either psychotherapy or medications, reverses this prefrontal-amygdala dysregulation. This review article summarizes current knowledge and theories available in the medical literature from NCBI’s PubMed database regarding the underlying brain networks involved in PTSD

Post-traumatic stress disorder: review of DSM criteria and functional neuroanatomy

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for post-traumatic stress disorder (PTSD) consist of over twenty possible symptoms that can be divided into six broad categories. These categories correlate with specific brain networks that regulate emotions, behaviors, and autonomic function. Normal functioning of these networks depends on two key regions; the prefrontal cortex and the amygdala. The prefrontal cortex provides top-down executive control over amygdala, whereas the amygdala is critical for threat detection and activation of the ‘fight or flight’ response. Events that trigger extreme and/or prolonged fear can cause persisting dysregulation within the prefrontal-amygdala circuit; resulting in PTSD symptomatology. Studies indicate that effective treatment of PTSD, either psychotherapy or medications, reverses this prefrontal-amygdala dysregulation. This review article summarizes current knowledge and theories available in the medical literature from NCBI’s PubMed database regarding the underlying brain networks involved in PTSD

Topical administration of psychotropic medications in pluronic lecithin organogel to treat patients with dementia: A retrospective observational study

OBJECTIVE: Treatment of mood and behavioral symptoms in geriatric patients with advanced dementia may be impeded by poor compliance with oral medications. Pluronic lecithin organogel (PLO) is a compounding substrate that can be used for the topical administration of psychotropic medications. METHODS: Charts of patients treated with psychotropic medications compounded with PLO cream were reviewed for treatment outcomes. All patients were treated by a nursing home outreach service. RESULTS: Records from twenty-four patients, mean age 86.8 + 5.9, were reviewed. Common psychiatric symptoms included agitation, aggressive behavior, and depression. Medications most commonly administered as a PLO cream included quetiapine and venlafaxine. All patients had mild to marked improvement in psychiatric symptoms. CONCLUSIONS: Pluronic lecithin organogel (PLO) may be an effective option for the topical administration of psychiatric medications in geriatric patients with dementia who are not compliant with oral medications

Energetics, electronic structure and electric polarization of basal stacking faults in wurtzite GaN and ZnO

We investigate the effect of basal-plane stacking faults on the structural, electronic, and polarization properties of wurtzite GaN and ZnO. This theoretical study is performed within density-functional theory (DFT) using periodic hexagonal supercells. Both formation energies and band structures are obtained by means of total-energy calculations. The type-I stacking fault is observed to have the lowest formation energy, followed by type-II and finally the extrinsic stacking fault. In order to overcome the inherent shortcoming of DFT in reproducing band gaps, the generalized-gradient approximation is used in combination with the modified Becke-Johnson functional. It is shown that all stacking faults studied maintain a direct gap whose value is lower than that in the ideal defect-free crystals. The lowering in the band gap allows the creation of quantum-well regions at wurtzite/zincblende interfaces. In addition, we provide a consistent set of polarization parameters derived from the Berry-phase method. We find a trend of decreasing (increasing) spontaneous polarization and piezoelectric coefficient (polarization charge) in going from type-I to type-II to extrinsic stacking faults. We compare our results to experimental and theoretical data available from the literature and explain the observed trends in terms of the properties of the wurtzite and zincblende polytypes of both materials

Physiological Trade-Offs in Self-Maintenance: Plumage Molt and Stress Physiology in Birds

Trade-offs between self-maintenance processes can affect life-history evolution. Integument replacement and the stress response both promote self-maintenance and affect survival in vertebrates. Relationships between the two processes have been studied most extensively in birds, where hormonal stress suppression is down regulated during molt in seasonal species, suggesting a resource-based trade-off between the two processes. The only species found to differ are the rock dove and Eurasian tree sparrow, at least one of which performs a very slow molt that may reduce resource demands during feather growth, permitting investment in the stress response. To test for the presence of a molt–stress response trade-off, we measured hormonal stress responsiveness during and outside molt in two additional species with extended molts, red crossbills (Loxia curvirostra) and zebra finches (Taeniopygia guttata). We found that both species maintain hormonal stress responsiveness during molt. Further, a comparative analysis of all available species revealed a strong relationship between molt duration and degree of hormonal suppression. Though our results support trade-off hypotheses, these data can also be explained by alternative hypotheses that have not been formally addressed in the literature. We found a strong relationship between stress suppression and seasonality of breeding and evidence suggesting that the degree of suppression may be either locally adaptable or plastic and responsive to local environmental conditions. We hypothesize that environmental unpredictability favors extended molt duration, which in turn allows for maintenance of the hormonal stress response, and discuss implications of a possible trade-off for the evolution of molt schedules

Spatiotemporal Imaging of the Acoustic Field Emitted by a Single Copper Nanowire

International audienceThe monochromatic and geometrically anisotropic acoustic field generated by 400 nm and 120 nm diameter copper nanowires simply dropped on a 10 µm silicon membrane is investigated in transmission using three-dimensional time-resolved femtosecond pump-probe experiments. Two pump-probe time-resolved experiments are carried out at the same time on both side of the silicon substrate. In reflection, the first radial breathing mode of the nanowire is excited and detected. In transmission, the longitudinal and shear waves are observed. The longitudinal signal is followed by a monochromatic component associated with the relaxation of the nanowire's first radial breathing mode. Finite Difference Time Domain (FDTD) simulations are performed and accurately reproduce the diffracted field. A shape anisotropy resulting from the large aspect ratio of the nanowire is detected in the acoustic field. The orientation of the underlying nanowires is thus acoustically deduced

NIHTS: the near-infrared high throughput spectrograph for the Discovery Channel Telescope

NIHTS is a first-generation instrument now in use on Lowell Observatory’s Discovery Channel Telescope. It is a nearinfrared prism spectrograph of the BASS design featuring high throughput and low dispersion that is intended for observations of faint solar system and astrophysical objects over the YJHK spectral range. An unusual feature is its ability to observe simultaneously with the Large Monolithic Imager, an optical CCD camera, by means of a dichroic fold mirror. This is particularly valuable for time-variable targets such as Kuiper Belt Objects, asteroids, exoplanet transits, and brown dwarfs. We describe its design details and performance both in the lab and on the telescope

In situ bending of an Au nanowire monitored by micro Laue diffraction

International audienceThis article reports on the first successful combination of micro Laue (µLaue) diffraction with an atomic force microscope for in situ nanomechanical tests of individual nanostructures. In situ three-point bending on self-suspended gold nanowires was performed on the BM32 beamline at the ESRF using a specially designed atomic force microscope. During the bending process of the self-suspended wire, the evolution of µLaue diffraction patterns was monitored, allowing for extraction of the bending angle of the nanowire. This bending compares well with finite element analysis taking into account elastic constant bulk values and geometric nonlinearities. This novel experimental setup opens promising perspectives for studying mechanical properties at the nanoscale

Combined coherent x-ray micro-diffraction and local mechanical loading on copper nanocrystals

Coherent x-ray micro-diffraction and local mechanical loading can be combined to investigate the mechanical deformation in crystalline nanostructures. Here we present measurements of plastic deformation in a copper crystal of sub-micron size obtained by loading the sample with an Atomic Force Microscopy tip. The appearance of sharp features in the diffraction pattern, while conserving its global shape, is attributed to crystal defects induced by the tip