The genomics of neonatal abstinence syndrome

Significant variability has been observed in the development and severity of neonatal abstinence syndrome (NAS) among neonates exposed to prenatal opioids. Since maternal opioid dose does not appear to correlate directly with neonatal outcome, maternal, placental, and fetal genomic variants may play important roles in NAS. Previous studies in small cohorts have demonstrated associations of variants in maternal and infant genes that encode the μ-opioid receptor (OPRM1), catechol-O-methyltransferase (COMT), and prepronociceptin (PNOC) with a shorter length of hospital stay and less need for treatment in neonates exposed to opioids in utero. Consistently falling genomic sequencing costs and computational approaches to predict variant function will permit unbiased discovery of genomic variants and gene pathways associated with differences in maternal and fetal opioid pharmacokinetics and pharmacodynamics and with placental opioid transport and metabolism. Discovery of pathogenic variants should permit better delineation of the risk of developing more severe forms of NAS. This review provides a summary of the current role of genomic factors in the development of NAS and suggests strategies for further genomic discovery

Sensitive detection of methane at 3.3 μm using an integrating sphere and interband cascade laser

Detection of methane at 3.3μm using a DFB Interband Cascade Laser and gold coated integrating sphere is performed. A 10cm diameter sphere with effective path length of 54.5cm was adapted for use as a gas cell. A comparison between this system and one using a 25cm path length single-pass gas cell is made using direct TDLS and methane concentrations between 0 and 1000 ppm. Initial investigations suggest a limit of detection of 1.0ppm for the integrating sphere and 2.2ppm for the single pass gas cell. The system has potential applications in challenging or industrial environments subject to high levels of vibration

Blade tip rubbing stress prediction

A linear analysis was performed to determine the dynamic response of a turbine blade to intermittent rubbing against a tip seal. The response analysis consisted of a parametric study where the rubbing friction force was assumed to vary as a half sine wave over a preselected contact arc. The length of the contact arc, as well as the pump speed, was varied to determine the effects of each. Results show that for a given contact arc there are distinct critical speeds at which the blade response becomes a maximum

The costs of conflict

A new study by researchers from The University of Queensland and Shift (an independent, non-profit center for business and human rights practice)/Harvard Kennedy School has uncovered the true scale of the costs companies incur when they come into conflict with local communities

Vertical Orientation in a New Gobioid Fish from New Britain

While visiting Rabaul, New Britain, during Cruise 6 of the Stanford University vessel "Te Vega" we observed and collected specimens of a small gobioid fish that swam and hovered vertically, with its head up, in midwater close to pockets in the wall of an underwater cliff at depths below 30 feet. Many kinds of fishes, for example scorpaenids and cottoids, are known to orient vertically in contact with a substrate. There are fewer examples of vertically oriented fishes in midwater; among the best known are the seahorses and centriscids. Observations have also been made on vertically oriented mesopelagic fishes. Barham (1966) has seen myctophids hovering vertically, as well as swimming upward and downward. Paralepidids are also known to be vertical swimmers (Peres, 1958; Bernard, 1958; Cohen, personal observations). We have found, however, no previous record of this habit in gobioid fishes and our observations are presented herewith. We have been unable to identify the fish with any known form, and we describe it as a ne

Dynamics of Natural Killer cell receptor revealed by quantitative analysis of photoswitchable protein

Natural Killer (NK) cell activation is dynamically regulated by numerous activating and inhibitory surface receptors that accumulate at the immune synapse. Quantitative analysis of receptor dynamics has been limited by methodologies which rely on indirect measurements such as fluorescence recovery after photobleaching. Here, we report a novel approach to study how proteins traffic to and from the immune synapse using NK cell receptors tagged with the photoswitchable fluorescent protein tdEosFP, which can be irreversibly photoswitched from a green to red fluorescent state by ultraviolet light. Thus, following a localized switching event, the movement of the photoswitched molecules can be temporally and spatially resolved by monitoring fluorescence in two regions of interest. By comparing images with mathematical models, we evaluated the diffusion coefficient of the receptor KIR2DL1 (0.23 +- 0.06 micron^2/s) and assessed how synapse formation affects receptor dynamics. Our data conclude that the inhibitory NK cell receptor KIR2DL1 is continually trafficked into the synapse and remains surprisingly stable there. Unexpectedly however, in NK cells forming synapses with multiple target cells simultaneously, KIR2DL1 at one synapse can relocate to another synapse. Thus, our results reveal a previously undetected inter-synaptic exchange of protein.Comment: 25 pages, 5 figure

Hidden variable interpretation of spontaneous localization theory

The spontaneous localization theory of Ghirardi, Rimini, and Weber (GRW) is a theory in which wavepacket reduction is treated as a genuine physical process. Here it is shown that the mathematical formalism of GRW can be given an interpretation in terms of an evolving distribution of particles on configuration space similar to Bohmian mechanics (BM). The GRW wavefunction acts as a pilot wave for the set of particles. In addition, a continuous stream of noisy information concerning the precise whereabouts of the particles must be specified. Nonlinear filtering techniques are used to determine the dynamics of the distribution of particles conditional on this noisy information and consistency with the GRW wavefunction dynamics is demonstrated. Viewing this development as a hybrid BM-GRW theory, it is argued that, besides helping to clarify the relationship between the GRW theory and BM, its merits make it worth considering in its own right.Comment: 13 page

Predicting spatial spread of rabies in skunk populations using surveillance data reported by the public

Background: Prevention and control of wildlife disease invasions relies on the ability to predict spatio-temporal dynamics and understand the role of factors driving spread rates, such as seasonality and transmission distance. Passive disease surveillance (i.e., case reports by public) is a common method of monitoring emergence of wildlife diseases, but can be challenging to interpret due to spatial biases and limitations in data quantity and quality. Methodology/Principal findings: We obtained passive rabies surveillance data from dead striped skunks (Mephitis mephitis) in an epizootic in northern Colorado, USA. We developed a dynamic patch-occupancy model which predicts spatio-temporal spreading while accounting for heterogeneous sampling. We estimated the distance travelled per transmission event, direction of invasion, rate of spatial spread, and effects of infection density and season. We also estimated mean transmission distance and rates of spatial spread using a phylogeographic approach on a subsample of viral sequences from the same epizootic. Both the occupancy and phylogeographic approaches predicted similar rates of spatio-temporal spread. Estimated mean transmission distances were 2.3 km (95% Highest Posterior Density (HPD95): 0.02, 11.9; phylogeographic) and 3.9 km (95% credible intervals (CI95): 1.4, 11.3; occupancy). Estimated rates of spatial spread in km/year were: 29.8 (HPD95: 20.8, 39.8; phylogeographic, branch velocity, homogenous model), 22.6 (HPD95: 15.3, 29.7; phylogeographic, diffusion rate, homogenous model) and 21.1 (CI95: 16.7, 25.5; occupancy). Initial colonization probability was twice as high in spring relative to fall. Conclusions/Significance: Skunk-to-skunk transmission was primarily local (< 4 km) suggesting that if interventions were needed, they could be applied at the wave front. Slower viral invasions of skunk rabies in western USA compared to a similar epizootic in raccoons in the eastern USA implies host species or landscape factors underlie the dynamics of rabies invasions. Our framework provides a straightforward method for estimating rates of spatial spread of wildlife diseases

Unified theory of the ab-plane and c-axis penetration depths of underdoped cuprates

We formulate a model describing the doping (x) and temperature (T) dependence of the ab-plane and c-axis penetration depth of a cuprate superconductor. The model incorporates the suppression of the superfluid density with underdoping as the system approaches the Mott-Hubbard insulating state by augmenting a d-wave BCS model with a phenomenological charge renormalization factor that is vanishingly small for states away from the nodes of the d-wave pair potential but close to unity in the vicinity of the nodes. The c-axis penetration depth is captured within a model of incoherent electron tunneling between the CuO2 planes. Application of this model to the recent experimental data on the high-purity single crystals of YBa2Cu 3O6 + δ implies existence of a nodal protectorate, a k-space region in the vicinity of the nodes whose size decreases in proportion to x, in which d-wave quasiparticles remain sharp even as the system teeters on the brink of becoming an insulator. The superfluid density, which is extremely small for these samples, also appears to come exclusively from these protected nodal regions