Final results for the neutron -asymmetry parameter A0 from the UCNA experiment

The UCNA experiment was designed to measure the neutron β-asymmetry parameter A0 using polarized ultracold neutrons (UCN). UCN produced via downscattering in solid deuterium were polarized via transport through a 7 T magnetic field, and then directed to a 1 T solenoidal electron spectrometer, where the decay electrons were detected in electron detector packages located on the two ends of the spectrometer. A value for A0 was then extracted from the asymmetry in the numbers of counts in the two detector packages. We summarize all of the results from the UCNA experiment, obtained during run periods in 2007, 2008–2009, 2010, and 2011–2013, which ultimately culminated in a 0.67% precision result for A0.

First measurement of the neutron beta asymmetry with ultracold neutrons

We report the first measurement of an angular correlation parameter in neutron beta decay using polarized ultracold neutrons (UCN). We utilize UCN with energies below about 200 neV, which we guide and store for approximately 30 s in a Cu decay volume. The interaction of the neutron magnetic dipole moment with a static 7 T field external to the decay volume provides a 420 neV potential energy barrier to the spin state parallel to the field, polarizing the UCN before they pass through an adiabatic fast passage spin flipper and enter a decay volume, situated within a 1 T field in a 2x2pi solenoidal spectrometer. We determine a value for the beta-asymmetry parameter A_{0}=-0.1138+/-0.0046+/-0.0021.

Catalytic asymmetric synthesis of 1,1'-spirobi[indan-3,3'-dione] via a double intramolecular C-H insertion process

A highly efficient one-pot construction of optically active 1,1'-spirobi[indan-3,3'-dione] derivative (up to 80% ee) has been achieved by exploiting the double intramolecular C-H insertion reaction of dimethyl 2,2'-methylenebis(alpha-diazo-beta-oxobenzenepropanoate) under the influence of dirhodium(II) tetrakis[N-phthaloyl-(R or S)-tert-leucinate] as a catalyst.

Enantioselective total synthesis of a potent antitumor antibiotic, fredericamycin A

The asymmetric total synthesis of both enantiomers of the potent antitumor antibiotic fredericamycin A (1) is detailed based on the protocol for the construction of its peri-hydroxy polyaromatic skeleton bearing the chirality at the spiro carbon via a strong base-induced cycloaddition of suitably substituted homophthalic anhydrides (AB-ring unit) with an optically active CDEF-ring unit. Particular attention has been given to the novel synthesis of the optically active spiro carbon center by a stereospecific rearrangement of optically active benzofuzed-trans-epoxy acylates leading to spirocyclopentane-1,1'-indane systems. This method is quite useful for the construction of an optically active spiro compound and was applied to the synthesis of the optically pure CDEF-ring unit of 1. Cycloaddition of the optically pure CDEF-ring unit to AB-ring units prepared via benzyne afforded two natural and unnatural-type hexacyclic compounds, which were converted to natural and unnatural enantiomers of synthetic 1, and the absolute configuration of natural 1 was determined as S.

[Preservation, thawing and infusion of hematopoietic stem cells]

Peripheral blood stem cells can be stored by the following 3 methods: liquid storage, non-rate controlled freezing and rate controlled freezing. Methods of processing of these cells including thawing, ex vivo purging and infusion are described in detail.

Conservative management of post-operative peritoneal cysts associated with endometriosis

OBJECTIVE

To describe the usefulness of fine-needle aspiration cytology and drainage, followed by long-acting GnRH-agonist therapy in the management of post-operative peritoneal cysts with endometriosis.

METHODS

In six women who were diagnosed as having post-operative peritoneal cysts with endometriosis, fine-needle aspiration cytology and drainage was performed. Thereafter, four patients were treated with long-acting GnRH-agonists for 6 months. Two patients refused the treatment.

RESULTS

In all patients fine-needle aspiration yielded specimens which consisted of a population of mesothelial cells. The mean follow-up time was 4 years (range 3.5-5). The four patients treated with long-acting GnRH-agonists show no evidence of recurrence. In two patients who had no additional treatment, the recurrence of the cyst was noted 2 months and 5 months after the drainage.

CONCLUSION

Combination of fine-needle aspiration cytology and drainage and subsequent long-acting GnRH-agonist therapy can be a useful conservative management of post-operative peritoneal cysts associated with endometriosis.

Body stalk anomaly: prenatal diagnosis

Body stalk anomaly is a severe body wall defect, with maldevelopment of the hindgut and the presence of a very rudimentary umbilical cord. A case of prenatally-diagnosed body stalk anomaly is presented along with the discussion of the prenatal diagnosis and its management. Autopsy of the fetus showed abnormalities compatible with the maldevelopment of embryonic body folding. Prenatal ultrasonographic diagnosis of body stalk anomaly would permit the early termination of pregnancy or avoidance of surgical intervention.