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We have developed a storage bottle for ultracold neutrons (UCNs) in order to measure the UCN density at the beamports of the Paul Scherrer Institute's (PSI) UCN source. This paper describes the design, construction and commissioning of the robust and mobile storage bottle with a volume comparable to typical storage experiments (32 L) e.g. searching for an electric dipole moment of the neutron.

In this work, we present a methodology for the construction of the attainable region (AR) and for the synthesis of globally optimal reactor networks employing isothermal, steady-state, plug flow reactors (PFR), continuous-stirred tank reactors (CSTR) as well as mixing. The problem is solved using the novel Infinite DimEnsionAl State-space (IDEAS) approach. Within the IDEAS framework, reactor network synthesis is formulated as an infinite dimensional convex (linear) optimization problem. Pointwise identification of the reactor network's attainable region is shown to be equivalent to the solution of an infinite dimensional linear program. A finite dimensional approximation strategy is presented and illustrated on an example from the literature.

We have used copper-coated carbon fiber reinforced plastic (CuCFRP) for the construction of high and ultra-high vacuum recipients. The vacuum performance is found to be comparable to typical stainless steel used for this purpose. In test recipients we have reached pressures of 2E-8 mbar and measured a desorption rate of 1E-11 mbar*liter/s/cm^2; no degradation over time (2 years) has been found. Suitability for baking has been found to depend on the CFRP production process, presumably on the temperature of the autoclave curing. Together with other unique properties of CuCFRP such as low weight and being nearly non-magnetic, this makes it an ideal material for many high-end vacuum applications., 17 pages, 10 figures, to be published in NIMA

The new biomedical project Proscan requires reconstruction of the whole Nucleon Area. During this period, the proton irradiation facility for components testing will share the beam with the Proton Therapy Facility part of the area. Another low energy facility, suited for displacement effect studies, was reinstalled in the dedicated area near the eye cancer exposure site OPTIS. Both facilities are designed in a similar, flexible and user-friendly manner.

RHESSI uses nine Rotating Modulation Collimators (RMCs) for imaging, each consisting of a pair of grids mounted on the rotating spacecraft. The angular resolutions range from 2.3 arcsec to 3arcmin. The relative twist between the two grids of each pair is the most critical parameter. It must be less than 20 arcsec for the finest grid. After precision alignment, it is monitored by the Twist Monitoring System (TMS) to a few arcsec. The Sun-pointing must be known better than 0.4 arcsec for the image reconstruction. This is achieved by the Solar Aspect System (SAS), which consists of a set of three Sun sensors. Each sensor is focusing the filtered Sun light onto a linear CCD. The onboard Aspect Data Processor (ADP) selects the 6 limb positions, which over-define the pointing offset of the Sun center in respect to the imaging axis of the imager. The Roll Angle System (RAS) continuously measures the roll angle of RHESSI within arcmin accuracy. The RAS is a continuously operating CCD star scanner. The time of the passage of a star image over the CCD is recorded and defines the roll angle, comparing its pixel position and amplitude with a star map.

Irradiation facility for parasitic testing of electronic components was developed and is installed in PSI OPTIS area. Radiation effects experiments and testing are performed using proton beams with energies up to 65 MeV. The facility, constructed as a low energy extension to the PSI Proton irradiation Facility PIF, is designed in a similar, user friendly manner.

The Surrounding Field Compensation (SFC) system described in this work is installed around the four-layer Mu-metal magnetic shield of the neutron electric dipole moment spectrometer located at the Paul Scherrer Institute. The SFC system reduces the DC component of the external magnetic field by a factor of about 20. Within a control volume of approximately 2.5m x 2.5m x 3m disturbances of the magnetic field are attenuated by factors of 5 to 50 at a bandwidth from $10^{-3}$ Hz up to 0.5 Hz, which corresponds to integration times longer than several hundreds of seconds and represent the important timescale for the nEDM measurement. These shielding factors apply to random environmental noise from arbitrary sources. This is achieved via a proportional-integral feedback stabilization system that includes a regularized pseudoinverse matrix of proportionality factors which correlates magnetic field changes at all sensor positions to current changes in the SFC coils., 33 pages, 18 figures

In this study we assessed the expression of the Melan-A/MART-1 antigen by immunohistochemistry using monoclonal antibody A103 in 73 primary cutaneous melanomas and its correlation with tumor staging and patient survival. Melan-A/MART-1 was expressed in 90% of primary tumors, with loss of expression increasing with Breslow thickness. Kaplan-Meier analysis demonstrated a significantly reduced disease-free interval and overall survival rate for patients not expressing this antigen. The poor prognosis of such patients was even worse for those presenting with a primary melanoma and a Breslow thickness ofor = 1 mm. Thus, Melan-A/MART-1 is not only a useful and specific additional marker for the diagnosis of primary cutaneous melanoma, but it may also help refine the prognosis of patients with malignant melanoma.

The purpose of the HESSI RAS is to provide information on the roll angle of the rotation spacecraft. Precise knowledge of the roll angle is a necessary ingredient for image reconstruction. The RAS is a continuously operating star scanner that points out radially and observes stars at 75 degrees from the Sun direction using a commercial lens and a fast CCD. The passage of a star image over the CCD charges one or several pixels above threshold and the timing of this signal defines the roll angle, once the star has been identified by comparing its pixel position and amplitude with a star map. Roll angles at intermediate times are inferred by assuming uniform rotation. With a limiting star magnitude of mv equals 3 we expect to observe at least 1 star per revolution over 1 year; on the average we will detect about 10 stars/revolution.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The HESSI SAS is a set of three Sun sensors, which shall provide high bandwidth information on the solar pointing of the rotating spacecraft. The precision of

Flow cytometry offers a relatively simple method to determine the DNA content of colorectal cancers. However, the technique can not discover minor changes in karyotype which may characterize near-diploid tumors, nor will it detect very small populations of aneuploid cells. In an attempt to improve the detection of such cells, we incubated biopsy material prior to analysis. This method revealed an aneuploid subpopulation in one of two biopsies studied. This simple protocol may ultimately lead to a more accurate assessment of the ploidy in colon cancer.