Fabrication of 1 T Bi-2223 Superconducting Magnet with 92 mm Bore Diameter at 77 K

A Bi-2223 superconducting magnet for practical use in liquid nitrogen is designed and fabricated. Bi-2223 tapesprepared by ConTrolled Over Pressure (CT-OP) process are used for the winding, and the critical current at 77.3 K and self-field is in the range of 174–185 A. 28 double-pancake coils are resistively connected in series by copper terminals. Highcritical current tape is used for top and bottom double-pancake coils, since the magnetic field normal to the tape surface ishighest at the top and bottom of the magnet. Two iron plates at top and bottom of the magnet are used for reduction of thenormal component of magnetic field to the Bi-2223 tape, since the total performance of the magnet is determined by theminimum critical current at maximum normal magnetic field component to the tape. The inner bore diameter of the magnetis 92 mm. And the homogeneity of magnetic field of long-axis direction in 50 mmφ × 100 mm length is within 3%. Themaximum magnetic field at the center of the bore is over 1.0 T at 77.3 K.Proceedings of the Cryogenic Engineering Conference (2013) , June 17–21, 2013, Anchorage, Alaska, US

Increased behavioral and neuronal responses to a hallucinogenic drug in PACAP heterozygous mutant mice.

Accumulating evidence from human genetic studies implicates the pituitary adenylate cyclase-activating polypeptide (PACAP) gene as a risk factor for psychiatric disorders, including schizophrenia and stress-related diseases. Mice with homozygous disruption of the PACAP gene display profound behavioral and neurological abnormalities that are ameliorated with the atypical antipsychotic and dopamine D2 and serotonin (5-HT)2 antagonist risperidone and the 5-HT2 receptor antagonist ritanserin; however, the underlying mechanisms remain unknown. Here, we investigated if PACAP heterozygous mutant (PACAP(+/-)) mice, which appear behaviorally normal, are vulnerable to aversive stimuli. PACAP(+/-) mice were administered a 5-HT2 receptor agonist, (±)-2,5-dimethoxy-4-iodoamphetamine (DOI), a hallucinogenic drug, and their responses were compared with the littermate wild-type mice. After DOI injection, PACAP(+/-) mice showed increased head-twitch responses, while their behavior was normal after saline. DOI induced deficits in sensorimotor gating, as determined by prepulse inhibition, specifically in PACAP(+/-) mice. However, other 5-HT2 receptor-dependent responses, such as corticosterone release and hypothermia, were similarly observed in PACAP(+/-) and wild-type mice. c-Fos expression analysis, performed in various brain regions, revealed that the DOI-induced increase in the number of c-Fos-positive cells was more pronounced in 5-HT2A receptor-negative cells in the somatosensory cortex in PACAP(+/-) mice compared with wild-type mice. These results indicate that PACAP(+/-) mice exhibit specific vulnerability to DOI-induced deficits in cortical sensory function, such as exaggerated head-twitch responses and sensorimotor gating deficits. Our findings provide insight into the neural mechanisms underlying impaired behavioral responses in which 5-HT2 receptors are implicated

Effect of DOI on c-Fos expression.

<p>The number of c-Fos-positive cells in the mPFC (A), SSCx (B), VL-CPu (C), MD (D), BLA (E) and PVN (F) were determined in PACAP^+/+ (+/+) and PACAP^+/− (+/−) mice after injection of DOI (3 mg/kg) or saline. Values are expressed as the mean ± SEM (n = 5–6). Statistically significant differences were assessed with two-way ANOVA with post hoc Tukey-Kramer test. *<i>p</i><0.05, **<i>p</i><0.01.</p

DOI-induced PPI deficits in PACAP^+/− mice.

<p>Effects of DOI on PPI (A) and acoustic startle response (B) were examined in PACAP^+/+ (+/+) and PACAP^+/− (+/−) mice. DOI (1 mg/kg) was injected intraperitoneally 5 min before the experiments. Values are expressed as the mean ± SEM (n = 6–9). Differences were assessed with repeated three-way ANOVA with post hoc Tukey-Kramer test. *<i>p</i><0.05, **<i>p</i><0.01 vs. saline.</p

Number of c-Fos-positive/5-HT_2A receptor-negative cells is increased in the SSCx in PACAP^+/− mice.

<p>(A and B) Representative c-Fos immunofluorescence images (A) and quantitative data (B) in PACAP^+/+ and PACAP^+/− mice. (C and D) Representative double-immunofluorescence images showing the co-localization of DOI-induced c-Fos and 5-HT_2A receptor immunoreactivity (C) and quantitative data (D) in PACAP^+/+ and PACAP^+/− mice. Arrows indicate representative cells double-labeled for c-Fos and 5-HT_2A receptor, and arrowheads indicate those positive for c-Fos and negative for 5-HT_2A receptor. Values are expressed as the mean ± SEM (n = 4). Statistically significant differences were assessed with two-way ANOVA with post hoc Tukey-Kramer test. **<i>p</i><0.01.</p

Effect of DOI on the head-twitch response in PACAP^+/− mice.

<p>(A) PACAP^+/+ (open columns) and PACAP^+/− (closed columns) mice were treated with the indicated doses of DOI or saline. Head-twitch responses were counted over a 60-min period. (B) Time course of the effect of 1 mg/kg DOI administration on PACAP^+/+ (open circles) and PACAP^+/− (closed circles) mice. Values are expressed as the mean ± SEM (n = 3–4). Statistically significant differences were assessed by two-way ANOVA followed by Tukey-Kramer test. *<i>p</i><0.05, **<i>p</i><0.01 vs. PACAP ^+/+ mice; ^†<i>p</i><0.05, ^††<i>p</i><0.01 vs. saline.</p