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A computed tomography (CT) based treatment planning system for total body irradiation (TBI) is presented and compared with the commonly practiced lateral treatment delivery. The TBI regimen has been proved to be an essential conditional regimen for patients undergoing bone marrow transplantation. The advantage of the TBI regimen with bone marrow transplantation (BMT) in hematological malignancies can be offset by toxicities arising from TBI in posttransplant complications. With the increasing survival rates, the evaluation of long‐term side effects and quality of life has become an important area of research interest. There have been several treatment techniques developed over the decades designed to achieve accurate dose delivery and dose homogeneity. This paper reports on the verification of the dose delivery for a basic lateral technique using thermoluminescent dosimeters (TLDs) placed in an anthropomorphic phantom and its correlation with CT‐based treatment planning. CT‐based treatment plans on several patients were used to evaluate the doses delivered to the whole body and critical organs. A large variation in doses delivered to the whole body was demonstrated, with some parts of the bone marrow failing to receive the prescribed dose and some critical organs, such as the lungs, receiving excessive doses. Placing the arms at the sides only partially compensates for the increased transmission of the lungs because the arms only shadow part of the lung. This study shows that CT‐based treatment planning for TBI provides precise and accurate dose calculations and allows for the correlation of clinical outcomes with the doses actually delivered to various organs. PACS numbers: 87.53.Dq, 87.66.Xa, 87.66.Sq

This study examined adoptees' and birth parents' experiences in therapy, including the perceived level of helpfulness and preparation by therapists relating to adoption issues as a function of the year these experiences occurred. Participants consisted of 152 adoptees and 66 birth parents, with the majority (78%) of the respondents being female. Overall, adoption inquiry, addressing adoption issues, helpfulness, and preparedness by therapists increased from 1965 though the 1990s. Therapists who inquired about adoption (54%) or addressed adoption (72%) were perceived as being significantly more prepared and helpful compared to those therapists who did not inquire about or address adoption issues.

As traditional secrecy surrounding adoption has waned, the behavioral sciences, particularly the mental health community, have remained largely silent, particularly on postadoption issues. Reasons for this silence are suggested. Research on adoption is difficult to conduct. The mental health community may desire to see adoption as professional problem-solving and as a “favor” done to all involved. Problems in adoption thus represent both a failure on the part of those professionals and a favor gone bad. Fear that discussing adoption-related problems will lead to adoption itself being labeled as pathological is also likely operating to support the silence. Privacy issues for the adoptive and birth families are also important. Sexuality and childbirth have long been areas not sufficiently addressed, but with the addition of the “illegitimacy” common in adoption they are even more controversial. Issues of poverty, powerlessness, social class, and race also are difficult to face, as is the business aspect of adoption. Acknowledging the reasons for the silence may be the first step in addressing it. Other steps, such as continuing education programs and publication of information on postadoption issues are also suggested.

The process and dynamics of adoption have changed considerably in the last 50 years, assisted by both social change and new knowledge of human development. The current status of 3 important aspects of adoption is reviewed: 1) the general effects of relinquishment and adoption, 2) the effects of secrecy in adoption, and 3) the need to add information on the dynamics of adoption to the training of therapists. The articles contained in this special adoption issue of the Journal of Social Distress and the Homeless are summarized and are placed in context of the 3 aspects reviewed.

This study is an investigation of the level of preparation psychologists have in dealing with adoption issues and an assessment of the need for further education in treating triad members. A questionnaire was mailed to 497 psychologists randomly selected from the National Register of Health Service Providers in Psychology who received doctoral degrees between the years of 1990 and 1996. Two hundred and ten psychologists, all of whom were currently treating clients, participated in the study. Psychologists completed a Likert rating of their sense of preparation to treat triad members. The largest group (51%) rated themselves as “Somewhat prepared,” with the second largest group (23%) rating themselves as “Not very prepared.” Ninety percent reported they needed more education in adoption, and 81% reported interest in taking a continuing education course in adoption. Of the 210 participants, only 67 reported taking courses that dealt with adoption as part of their formal education. Of those psychologists who reported taking courses that involved adoption, they averaged only 1.3 courses during their undergraduate education, and 1.5 courses during graduate education, while the remaining 143 psychologists received no education in this area. When one considers the proportion of triad members seen clinically, this study suggests psychologists need more education and background information about the effects of the adoption process.

During the D–T operation of the International Thermonuclear Experimental Reactor (ITER), the dose inside ITER building is attributed to neutrons and gamma-rays streaming from various openings in the machine, whereas after shutdown, it is solely due to the decay gammas from activated components inside the building. In the present study, two cases of different geometrical arrangement are considered (Case A and Case C) in which the impact of the size of the opening of the NBI horizontal ports and presence of the NBI structure on the dose profiles everywhere in ITER building was studied and compared to the case (Case B) where all the horizontal ports are plugged. Contours and mapping of the dose rate profiles during operation, at shutdown, and at one-day, one-week, and one-month after shutdown, were generated for the three cases. Zone classification requirements for each hall/room and gallery of the building in terms of the maximum allowed exposure dose during operation and after shutdown were examined to identify where these requirements are met during ‘hands-on’ maintenance activities. It is shown that the requirements are satisfied at all times after shutdown in the halls above the ground, even during operation. For the conservative Case A, the dose rates are excessively high inside the equatorial NBI hall and inside the access halls above and below (divertor hall). In Case C, all the halls/vaults and galleries are accessible 1-week after shutdown, except inside the NBI hall whose dose rate (6.2 × 105 μSv h−1) exceeds the required zone classification (3–2 μSv h−1). All areas are accessible a week after shutdown in Case B which represents the building side away from the NBI ports. However, in all these cases, the accessibility criterion inside the rooms beneath the cryostat is not met at all times after shutdown due to the rather thin bottom bioshield (50 cm) which may necessitate some design changes.

Brush-forming polymers are being used in a variety of applications, and by using recombinant DNA technology, there exists the potential to produce protein-based polymers that incorporate unique structures and functions in these brush layers. Despite this potential, production of protein-based brush-forming polymers is not routinely performed. For the design and production of new protein-based polymers with optimal brush-forming properties, it would be desirable to have a cloning strategy that allows an iterative approach wherein the protein based-polymer product can be produced and evaluated, and then if necessary, it can be sequentially modified in a controlled manner to obtain optimal surface density and brush extension. In this work, we report on the development of a cloning strategy intended for the production of protein-based brush-forming polymers. This strategy is based on the assembly of modules of DNA that encode for blocks of protein-based polymers into a commercially available expression vector; there is no need for custom-modified vectors and no need for intermediate cloning vectors. Additionally, because the design of new protein-based biopolymers can be an iterative process, our method enables sequential modification of a protein-based polymer product. With at least 21 bacterial expression vectors and 11 yeast expression vectors compatible with this strategy, there are a number of options available for production of protein-based polymers. It is our intent that this strategy will aid in advancing the production of protein-based brush-forming polymers.

We introduce a new method for the stabilization of colloidal particles via the synthesis and adsorption of unnatural proteins. Biosynthesis of protein-based polymers offers the advantages of preparation of complex sequences through control of the primary sequence, monodisperse polymers, ease of combinatorial search for anchor blocks, environmentally friendly synthesis, use of water as the solvent, and incorporation of a palette of known natural proteins. We have synthesized an unnatural protein with the sequence thioredoxin-Pro(39)Glu(10) for modification of the forces between alumina particles. The polyglutamate sequence, Glu(10), is anionic (pH > 3) and is designed to anchor the protein to positively charged solids, e.g. alumina in water (pH < 9). The polyproline sequence, Pro(39), is neutral. The thioredoxin is a recombinant form of the natural globular protein with a histidine patch (His-patch-thioredoxin) and is zwitterionic. The combined thioredoxin-Pro(39) sequence is hydrophilic with pI approximately 6.3. This block is designed to remain in solution, thereby providing a steric barrier to the approach of two particles in a range of salt and pH conditions. Ellipsometry experiments show that thioredoxin-Pro(39)Glu(10) does adsorb to alumina. Force measurements with the atomic force microscopy (AFM) colloid probe technique show that adsorption of thioredoxin-Pro(39)Glu(10) leads to repulsive forces that decay exponentially with the separation between the surfaces and are independent of salt concentration in the range 0.001-0.1 M KNO(3). This demonstrates that the repulsive forces are not electrostatic. We hypothesize that the repulsion is due to confinement and loss of solvent for the adsorbed polymer; the forces are similar to those expected for a polymer brush. Force measurements between thioredoxin-coated alumina surfaces also show a repulsive force, but the force has a decay length that is consistent with electrostatic double-layer forces: the thioredoxin has not neutralized the surface charge of the underlying alumina. Our results point to interesting future experiments where recombinant DNA technology could be used to synthesize fusion proteins containing useful natural proteins and an anchor. This may allow preparation, via single-step aqueous self-assembly, of anchored proteins that maintain their natural structure. Our technique is not limited to homopolymer blocks; more complex primary sequences can be used.

The PhoStrip process is a biological-chemical process which removes phosphorus from wastewater. This article presents descriptions of the PhoStrip process, a plant-scale test of the process, the design of a 152,000 m3/d PhoStrip facility, and the start-up and initial full scale operation of the PhoStrip facility, all in association with the expansion of the Reno-Sparks Joint Water Pollution Control Plant in Nevada, USA. The PhoStrip process has demonstrated the capability of removing phosphorus to effluent levels of less than 0.5 mg/l at operating costs much less than operating costs associated with conventional chemical processes.