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Objective:This study aims to determine whether fetal meconium passage is associated with autism.Study Design:This retrospective birth cohort analysis of 9 945 896 children born in California 1991 to 2008 linked discharge diagnosis and procedure codes for prenatal stressors, meconium-stained amniotic fluid (MSAF) and meconium aspiration syndrome (MAS) with autism diagnoses for 47 277 children through 2012. We assessed the relative risk of autism by meconium status using logistic regression, adjusting for demographic and clinical features.Results:Children exposed to meconium (MSAF and MAS) were more likely to be diagnosed with autism in comparison with unexposed children (0.60% and 0.52%, vs 0.47%, respectively). In adjusted analyses, there was a small increase in autism risk associated with MSAF exposure (adjusted relative risk (aRR) 1.18, 95% confidence interval (CI) 1.12 to 1.25), and a marginal association that failed to achieve significance between MAS and autism (aRR 1.08, 95% CI 0.98 to 1.20).Conclusion:Resuscitation of neonates with respiratory compromise from in utero meconium exposure may mitigate long-term neurodevelopmental damage.

Human adolescence is a crucial stage of neurological development during which ethanol (EtOH) consumption is often at its highest. Alcohol abuse during adolescence may render individuals at heightened risk for subsequent alcohol abuse disorders, cognitive dysfunction, or other neurological impairments by irreversibly altering long‐term brain function. To test this possibility, we modeled adolescent alcohol abuse (i.e., intermittent EtOH exposure during adolescence [AIE]) in rats to determine whether adolescent exposure to alcohol leads to long‐term structural and functional changes that are manifested in adult neuronal circuitry. We specifically focused on hippocampal area CA1, a brain region associated with learning and memory. Using electrophysiological, immunohistochemical, and neuroanatomical approaches, we measured post‐AIEchanges in synaptic plasticity, dendritic spine morphology, and synaptic structure in adulthood. We found that AIE‐pretreated adult rats manifest robust long‐term potentiation, induced at stimulus intensities lower than those required in controls, suggesting a state of enhanced synaptic plasticity. Moreover, AIEresulted in an increased number of dendritic spines with characteristics typical of immaturity. Immunohistochemistry‐based analysis of synaptic structures indicated a significant decrease in the number of co‐localized pre‐ and postsynaptic puncta. This decrease is driven by an overall decrease in 2 postsynaptic density proteins, PSD‐95 and SAP102. Taken together, these findings reveal that repeated alcohol exposure during adolescence results in enduring structural and functional abnormalities in the hippocampus. These synaptic changes in the hippocampal circuits may help to explain learning‐related behavioral changes in adult animals preexposed to AIE.

Highly regioselective, catalytic asymmetric reductive coupling reactions of 1,3-enynes and ketones have been achieved using catalytic amounts of Ni(cod)2 and a P-chiral, monodentate ferrocenyl phosphine ligand. These couplings represent the first examples of catalytic, intermolecular reductive coupling of alkynes and ketones, enantioselective or otherwise, and afford synthetically useful 1,3-dienes possessing a quaternary carbinol stereogenic center in up to 70% ee.

The rate of the methylenecyclopropane rearrangement is remarkably enhanced by the 1,6-methano[10]annulene group, which greatly stabilizes the biradical intermediate. The diastereomeric products argue against a concerted rearrangement mechanism and support a stabilized biradical intermediate that lives long enough to undergo rotation before ring closure.

To determine the expression pattern and cellular source of matrix metalloproteinases (MMPs) in chronic inflammatory demyelinating polyneuropathy (CIDP) and nonsystemic vasculitic neuropathy (NSVN).

Three physically distinct boundary conditions have been previously used in the real space computer simulation of point defects. The difference between them is discussed and their effect on vacancy formation energy is investigated.

In this paper the various calculational procedures for the evaluation of cavity growth in irradiated metals under stress are critically examined and limitations to their use are described. Compressive stress reduces cavity growth over the whole temperature range studied (600-750°C). At temperatures in excess of 650°C, in the absence of alternative sinks for gas, cavities grow as overpressurized bubbles. At high temperatures cavity growth rate is sensitive to the presence of even a low density of alternative sinks for gas.

The diffusion equations which describe the point defect distributions in electron irradiated metal foils have been solved by a computer iterative technique.

This paper presents a quantitative analysis of void swelling experiments in pure copper irradiated in a high voltage electron microscope (HVM). Both dislocation loop growth and void growth were measured over the temperature range 140-320°C. The simultaneous measurement of these growth rates allows both the vacancy migration energy, E, v, and the dislocation bias to be unambiguously determined and the analysis can also distinguish the void sink strength from the other parameters involved. It was found that void growth cannot be adequately described simply with the assumption of random diffusion of point defects to the sink and we choose to describe the growth successfully with initial control by defect transfer across the void interface. Alternative descriptions may be possible.The analysis was performed numerically using the Rate Theory Continuum (RTC) model with suitable modifications to include the influence of defect recombination on the various sink strengths. Such modifications are made necessary by the choice of the type of irradiation employed, i.e. high-flux irradiation in the HVM. The emphasis throughout has been to use a model that is directly applicable to bulk metals under neutron irradiation. For this reason also, the foil surfaces have been represented as a continuum sink for defects. We find from the analysis that JSmv≈0·77 eV with an interstitial volume ΔVI≈0·6 Ω corresponding to a dislocation bias of 6-7%. This paper presents a quantitative analysis of void swelling experiments in pure copper irradiated in a high voltage electron microscope (HVM). Both dislocation loop growth and void growth were measured over the temperature range 140-320°C. The simultaneous measurement of these growth rates allows both the vacancy migration energy, Emv, and the dislocation bias to be unambiguously determined and the analysis can also distinguish the void sink strength from the other parameters involved. It was found that void growth cannot be adequately described simply with the assumption of random diffusion of point defects to the sink and we choose to describe the growth successfully with initial control by defect transfer across the void interface. Alternative descriptions may be possible.

The years 1971-73 proved difficult for the Fife Regional Water Division, for the region received rainfall amounting to only 72.4% of the long term average. A study is made of the relationship between rainfall amount and atmospheric circulation patterns for the 1961-70 and 1971-73 periods. It is suggested that the low rainfall receipts are due to a decline in importance of the Westerly circulation over the Scottish mainland.

The diffusion equations which describe the distribution of point defects around an isolated void have been solved by a computer iterative technique. The void sink strengths have been calculated in a manner consistent with the rate theory continuum model.Any competition for defects between the void and either fixed sinks or mutual recombination results in an increase in the void sink strengths.An empirical relationship between the resulting void sink strengths and the perturbing parameters is developed from the computer simulation data.

Pyocyanine, a low-molecular-weight phenazine pigment produced by Pseudomonas aeruginosa, has previously been shown to strongly inhibit human lymphocyte blastogenesis. We now report that synthetic pyocyanine can also affect the generation of superoxide by human peripheral blood polymorphonuclear leukocytes (PMNs) in a dose-dependent manner. Superoxide production by PMNs stimulated with phorbol myristate acetate (PMA) was measured in the presence and absence of pyocyanine, phenazine, and trifluoperazine, a phenothiazine of similar chemical structure to the phenazine pigments. Pyocyanine at 50 microM inhibited superoxide production to 28.9 +/- 2.8% of PMA control values, whereas at the lower concentration of 1 microM, the production of superoxide was significantly enhanced (203 +/- 31.7% of PMA control values). Phenazine, the tricyclic parent compound of pyocyanine, had only a minor effect. Trifluoperazine had a marked inhibitory effect on superoxide generation at concentrations above 1 microM. None of the compounds induced superoxide generation in the absence of PMA. Pyocyanine at all concentrations, unlike phenothiazines, had very little effect on the release of neutrophil granule enzymes. The effect of P. aeruginosa phenazine pigments on polymorphonuclear phagocytes is of significance, since inhibition of host PMN function at sites of infection could result in ineffective bacterial killing, whereas enhanced PMN function could lead to greater tissue damage. These two possibilities are not mutually exclusive and may coexist depending on local pyocyanine concentrations.

Three physically distinct boundary conditions have been previously used in the real space computer simulation of point defects. The difference between them is discussed and their effect on vacancy formation energy is investigated. [ABSTRACT FROM PUBLISHER]

A procedure is described for determining the enhancement of de Haas-van Alphen Dingle temperatures due to mosaic spread of crystalline orientation. The procedure is based on the method of Lowndes, Miller, and Springford for the determination of the anisotropy of the electron-impurity scattering lifetime, and permits extension of their method to include Dingle temperatures measured for off-symmetry magnetic field directions. The procedure is illustrated by measurements made on an AuCu alloy for which preliminary maps of the electronic lifetime anisotropy are given.

Basic relationships that control the dynamic performance of toric variable-speed drives are studied. These basic toric relationships are then utilized to derive seven linear differential equations that describe a commercial model of a toric transmission. Experimental verification of these equations is made to support the theoretical work. By means of a numerical evaluation of the transfer functions, a simplified interpretation is made to show the relationships between transmission parameters and dynamic performance.

Performance of a servomechanism that provides accurate, continuous control of mechanical power is fundamentally governed by the actuator used to meter power to the load. These actuators, when used in exacting control applications, tend to be complex, expensive, and critical. This paper describes a mechanical servoactuator concept based on the toric-transmission principle that has the potential of providing precise power control in a relatively simple and rugged package. Actuator kinematic principles are explained and equations that describe these relationships are presented to illustrate both steady-state and dynamic performance characteristics. Closed-loop control techniques are discussed with specific emphasis on the load-acceleration control feature inherent with this actuator concept. Experimental performance data obtained from testing a 1-hp prototype model operated as a velocity servo are presented. Static velocity control accuracy of ±0.1 percent is readily obtained; transient-response times vary from 20 to 40 milliseconds depending on signal amplitude and load conditions.

Twelve novel di-, tri- and tetranucleotide microsatellite loci to the pinto abalone (Haliotis kamtschatkana) are described. Over 400 individuals were analysed at each microsatellite locus. Observed heterozygosities ranged from 0.44 to 0.93, and numbers of alleles from 20 to 63. Six of the loci contained excesses in homozygosity indicative of inbreeding, nonrandom mating, population admixture, or null alleles.

Fifteen polymorphic di-, tri- and tetranucleotide microsatellite markers were developed in Pacific herring (Clupea pallasi) to aid in the delineation of population structure of herring in British Columbia. Twelve of the microsatellite loci were analysed in over 4000 wild herring. Expected heterozygosities ranged 0.73–0.95, and only two loci significantly deviated from Hardy–Weinberg equilibrium.