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The personnel dosimetry operations team at the Los Alamos National Laboratory (LANL) has accepted the laser illuminated track etch scattering (LITES) dosemeter reader into its suite of radiation dose measurement instruments. The LITES instrument transmits coherent light from a He-Ne laser through the pertinent track etch foil and a photodiode measures the amount of light scattered by the etched tracks. A small beam stop blocks the main laser light, while a lens refocuses the scattered light into the photodiode. Three stepper motors in the current LITES system are used to position a carousel that holds 36 track etch dosemeters (TEDs). Preliminary work with the LITES system demonstrated the device had a linear response in counting foils subjected to exposures up to 50 mSv (5.0 rem). The United States Department of Energy requires that the annual general employee dose not exceed 50 mSv (5.0 rem). On a regular basis, LANL uses the Autoscan-60 reader system (Thermo Electron Corp.) for counting track etch dosemeters. However, LANL uses a 15 h etch process for CR-39 dosemeters, and this produces more and larger track etch pits than the 6 h etch used by many institutions. Therefore, LANL only uses the Autoscan-60 for measuring neutron dose equivalent up to exposure levels of approximately 3 mSv (300 mrem). The LITES system has a measured lower limit of detection of approximately 0.6 mSv (60 mrem), and it has a correlation coefficient of R (2) = 0.99 over an exposure range up to 500 mSv (50.0 rem). A series of blind studies were done using three methods: the Autoscan-60 system, manual counting by optical microscope and the LITES instrument. A collection of track etch dosemeters of unknown neutron dose equivalent (NDE) were analysed using the three methods, and the performance coefficient (PC) was calculated when the NDE became known. The Autoscan-60 and optical microscope methods had a combined PC = 0.171, and the LITES instrument had a PC = 0.194, where a PC less than or equal to 0.300 is considered satisfactory.

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One of the major challenges in neuroscience is to identify the changes which accompany aging and which contribute to the well-documented age-related deterioration in cognitive function. This is a particular challenge in the light of the vast array of reported changes, which include morphological changes like synaptic and perhaps cell loss, alteration in membrane composition and the resultant changes in function of membrane proteins, modulation of the hypothalamo-pituitary axis, impaired calcium homoeostatic mechanisms, alteration in enzyme function and decreased neurotransmitter release. In the past few years, evidence suggesting that an aged brain exhibits signs of oxidative stress and inflammatory stress has been accumulating, and recent evidence using microarray analysis has added support to this view. In this paper, we provide evidence to suggest that vitamin D3 acts as an anti-inflammatory agent and reverses the age-related increase in microglial activation and the accompanying increase in IL-1beta (interleukin-1beta) concentration.

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Los Alamos National Labs (LANL) has developed an etched track foil (CR-39) reader for neutron dose between 0 and 50.0 mSv. Currently, the US Department of Energy mandates general employee annual exposure not to exceed 50.0 mSv (5 rem). At LANL, due to a non-linear response at higher exposures. accepted practice only uses an Autoscan 60 system up to 3 mSv. The LITES system, however, has demonstrated linear response to 50 mSv, where the proprietary design measures the amount of laser light scattered by the etched tracks, proportional to dose. A collection of calibrated foils was counted by an Autoscan 60 and the LITES prototype, and the Autoscan 60 showed good linearity when counting exposure up to about 15 mSv, but not for higher exposures. From 0 to 50 mSv, the Autoscan 60 had a correlation coefficient of R2 = 0.941 and the LITES system had R2 = 0.991.

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UNLABELLED: Research findings have been mixed about pronoun case problems in the language-learning profile of children with specific language impairment (SLI). This study (N= 36) extended previous findings and located a number of error patterns using detailed error analyses. Results indicated that the children with expressive SLI produced more errors with third person singular (3Psg) pronouns than did their age-level peers, but they did not make more errors than their MLU-matched peers. Error patterns were similar in the children with SLI and their language-level peers. The most frequent type of error was the substitution of the objective case for the nominative case. More errors were made on the feminine pronoun, she, than on the masculine pronoun, he. Implications for theories and clinical practice were explored. EDUCATIONAL OBJECTIVES: As a result of this activity, the reader will (1) learn how children with SLI compare to their peers in producing third person pronouns, (2) learn the most common types of pronoun errors made by the children matched for mean length of utterance (MLU), and (3) evaluate how the findings relate to two current theories: one from typical language development and one from the area of SLI.

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The University of North Carolina at Chapel Hill evaluated five curricular models designed to improve education for health sciences librarianship. Three of the models enhanced existing degree and certificate programs, and two were new programs for working information professionals. Models were developed with input from experts and a Delphi study; the marketability of the models was tested through surveys of potential students and employers; and recommendations were made as a guide to implementation. The results demonstrated a demand for more specialized curricula and for retraining opportunities. Marketing data showed a strong interest from potential students in a specialized master's degree, and mid-career professionals indicated an interest in postmaster's programs that provided the ability to maintain employment. The study pointed to the opportunity for a center of excellence in health sciences information education to enable health sciences librarians to respond to their evolving roles.

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Ulnar-mammary syndrome is a rare pleiotropic disorder affecting limb, apocrine gland, tooth and genital development. We demonstrate that mutations in human TBX3, a member of the T-box gene family, cause ulnar-mammary syndrome in two families. Each mutation (a single nucleotide deletion and a splice-site mutation) is predicted to cause haploinsufficiency of TBX3, implying that critical levels of this transcription factor are required for morphogenesis of several organs. Limb abnormalities of ulnar-mammary syndrome involve posterior elements. Mutations in TBX5, a related and linked gene, cause anterior limb abnormalities in Holt-Oram syndrome. We suggest that during the evolution of TBX3 and TBX5 from a common ancestral gene, each has acquired specific yet complementary roles in patterning the mammalian upper limb.

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The University of North Carolina at Chapel Hill is devising and evaluating five curricular models designed to improve education for health sciences librarianship. These models fit into a continual learning process from the initial professional preparation to lifelong learning opportunities. Three of them enhance existing degree and certificate programs in the School of Information and Library Science (SILS) with a health sciences specialization, and two are new programs for working information professionals. The approaches involve partnerships among SILS, the Health Sciences Library, and the program in Medical Informatics. The planning process will study the feasibility of the proposed programs, test the marketability of the models to potential students and employers, and make recommendations about implementation.

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One hundred sixty-one MEDLINE searches conducted by third-year medical students were analyzed and evaluated to determine which search moves were used, whether those individual moves were effective, and whether there was a relationship between specific search behaviors and the effectiveness of the search strategy as a whole. The typical search included fourteen search statements, used seven terms or "limit" commands, and resulted in the display of eleven citations. The most common moves were selection of a database, entering single-word terms and free-text term phrases, and combining sets of terms. Syntactic errors were also common. Overall, librarians judged the searches to be adequate, and students were quite satisfied with their own searches. However, librarians also identified many missed opportunities in the search strategies, including underutilization of the controlled vocabulary, subheadings, and synonyms for search concepts. No strong relationships were found between specific search behaviors and search effectiveness (as measured by the librarians' or students' evaluations). Implications of these findings for system design and user education are discussed.

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Recent research has located extraordinary weakness in specifically language-impaired (SLI) children's development other than grammatical morphemes. A problem with pronoun case marking was reported to be more prevalent in SLI children than in normally developing children matched by mean length of utterance. However, results from the present study do not support that finding. Spontaneous utterances from 3 conversational contexts were generated by 3 groups of normal and SLI children and were analyzed for accuracy of pronoun usage. Third person singular pronouns were judged according to case, gender, number, person and cohesion based on their linguistic and nonlinguistic contexts. Results indicated that SLI children exhibited more total errors than their chronological peers, but not more than their language level peers. An analysis of error types indicated a similar pattern in pronoun case marking.

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The DNA binding of BMS 181176, an antitumor antibiotic derivative of rebeccamycin was characterized by DNA unwinding assays, as well as by fluorescence emission and polarization spectroscopic techniques. Unwinding and rewinding of supercoiled DNA was interpreted in terms of intercalation of BMS 181176 into DNA. BMS 181176 shows an enhanced fluorescence emission upon binding to the AT sequence and no enhancement upon binding to the GC sequence. BMS 181176 appears to be a weaker binder to poly(dAdT).poly(dAdT) compared to doxorubicin and ethidium bromide. When bound to DNA, the rotational motion of BMS 181176 is substantially decreased as evident from the increase in fluorescence polarization. BMS 181176 exhibits a range of binding strengths depending on the DNA. This is demonstrated by the Acridine Orange displacement assay using fluorescence polarization.

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OBJECTIVE: To determine which intraarticular steroids are used by rheumatologists and whether this use and associated practice vary with time and place of training. METHOD: American College of Rheumatology members were mailed questionnaires that focused on steroid use in the adult knee. RESULTS: The steroids favored by the respondents were methylprednisolone acetate (MPA), preferred most by those trained in the eastern U.S.; triamcinolone hexacetonide (TH), preferred by those trained in the Midwest and Southwest; and triamcinolone acetonide (TA), preferred by those trained in the West. Only TH was chosen primarily because of efficacy. Regardless of concentration, respondents used 1 ml of steroid. Most (especially those recently trained) combined steroid with local anesthetic. Post-injection instructions varied: 29% did not restrict weight-bearing; 8% recommended limited weight-bearing for 1 week or more. CONCLUSION: MPA, TH, and TA were favored. Associated techniques varied, based in part on where and when training took place. Research is needed to provide a more rational basis for clinical practice.

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Peering into health-care's future means examining social, economic and political issues. Knowing what's coming will help development professionals deal with this new world.

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