The ordered columnar structure of mouse filiform papillae

Examination of carefully oriented 1-mum and 5-mum sections of mouse dorsal tongue together with scanning electron microscope observations indicates a high degree of cellular organization in the papillae. It has been suggested that each filiform papilla consists of 2 dominant and 2 minor columns of cells. Labelling patterns of the basal cells have been investigated in relation to these columns.     

A technique for accurate planning of stereotactic brain implants prior to head ring fixation

PURPOSE: A two-step procedure is described for accurate planning of stereotactic brain implants prior to head-ring fixation. METHODS AND MATERIALS: Approximately 2 weeks prior to implant a CT scan without the head ring is performed for treatment-planning purposes. An entry point and a reference point, both marked with barium and later tattooed, facilitate planning and permit correlation of the images with a later CT scan. A plan is generated using a conventional treatment-planning system to determine the number and activity of I-125 seeds required and the position of each catheter. I-125 seed anisotropy is taken into account by means of a modification to the treatment planning program. On the day of the implant a second CT scan is performed with the head ring affixed to the skull and with the same points marked as in the previous scan. The planned catheter coordinates are then mapped into the coordinate system of the second CT scan by means of a manual translational correction and a computer-calculated rotational correction derived from the reference point coordinates in the two scans. RESULTS: The rotational correction algorithm was verified experimentally in a Rando phantom before it was used clinically. For analysis of the results with individual patients a third CT scan is performed 1 day following the implant and is used for calculating the final dosimetry. CONCLUSION: The technique that is described has two important advantages: 1) the number and activity of seeds required can be accurately determined in advance; and 2) sufficient time is allowed to derive the best possible plan.     

走新型工业化道路创节约型企业

金川集团有限公司切实加强能源管理。把节能降耗和技术改造结合起来。走工艺节能和效率节能的路子，取得了明显的效果。     

Sanmenxia strives to create aluminum industrial base

Contradiction between rich alumina resource and relatively weak electrolytic aluminum production capacity is the "bottleneck" inhibiting development of aluminum industry in San-menxia. During the period of "11th Five-Year Development", Sanmenxia will relay on its     

Enrichment programs to create a pipeline to biomedical science careers

The Student Educational Enrichment Programs at the Medical College of Georgia in the School of Medicine were created to increase underrepresented minorities in the pipeline to biomedical science careers. Eight-week summer programs are conducted for high school, research apprentice, and intermediate and advanced college students. There is a prematriculation program for accepted medical, dental, and graduate students. Between 1979 and 1990, 245 high school students attended 12 summer programs. Of these, 240 (98%) entered college 1 year later. In 1986, after eight programs, 162 (68%) high school participants graduated from college with a baccalaureate degree, and 127 responded to a follow-up survey. Sixty-two (49%) of the college graduates attended health science schools, and 23 (18%) of these matriculated to medical school. Of college students, 504 participated in 13 summer programs. Four hundred (79%) of these students responded to a questionnaire, which indicated that 348 (87%) of the 400 entered health science occupations and/or professional schools; 179 (45%) of these students matriculated to medical school. Minority students participating in enrichment programs have greater success in gaining acceptance to college and professional school. These data suggest that early enrichment initiatives increase the number of underrepresented minorities in the biomedical science pipeline.     

A new genetic algorithm technique in optimization of permanent 125I prostate implants

Real time optimized treatment planning at the time of the implant is desirable for ultrasound-guided transperineal 125I permanent prostate implants. Currently available optimization algorithms are too slow to be used in the operating room. The goal of this work is to develop a robust optimization algorithm, which is suitable for such application. Three different genetic algorithms (sGA, sureGA and securGA) were developed and compared in terms of the number of function evaluations and the corresponding fitness. The optimized dose distribution was achieved by searching the best seed distribution through the minimization of a cost function. The cost function included constraints on the periphery dose of the planned target volume, the dose uniformity within the target volume, and the dose to the critical structure. Adjustment between the peripheral dose, the dose uniformity and critical structure dose can be achieved by varying the weighting factors in the cost function. All plans were evaluated in terms of the dose nonuniformity ratio, the conformation number and the dose volume histograms. Among these three GA algorithms, the securGA provided the best performance. Within 2500 function evaluations, the near optimum results were obtained. For a large target volume (5 cm x 4 cm x 4.5 cm) including urethra with 20 needles, the computer time needed for the optimization was less than 5 min on a HP735 workstation. The results showed that once the best set of parameters was found, they were applicable for all sizes of prostate volume. For a fixed needle geometry, the optimized plan showed much better dose distribution than that of nonoptimized plan. If the critical structure was considered in the optimization, the dose to the critical structure could be minimized. In the cases of irregular and skewed needle geometry, the optimized treatment plans were almost as good as ideal needle geometry. It is concluded that this new genetic algorithm (securGA) allows for an efficient and rapid optimization of dose distribution, which is suitable for real time treatment planning optimization for ultrasound-guided prostate implant.     

Using constraints to create novelty: A case study.

The development of Richard Serra’s sculpture is presented as a case study using a constraint-based model of novelty (Stokes, 2005, 2007). The model was developed from two problem-solving precedents: Reitman’s (1965) idea that paired constraints direct and limit search in a problem space; and Simon’s (1973), that search can only lead to novel solutions if the problem space is ill-structured. Ill-structured means that a problem space is incompletely specified or defined. The study shows how paired constraints restructure problem spaces in ways that make novelty possible and probable (Stokes, 2007). Possible means that novelty may or may not happen; probable, that paired constraints facilitate the happening. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The cost of dental implants as compared to that of conventional strategies

The effectiveness of dental implants is widely studied, especially in terms of their clinical outcomes. However, from the policymaker's point of view, variables other than safety and efficacy, such as the costs and effectiveness of dental implants as compared to other treatment alternatives, are vital in decision making. This paper compares the costs of different treatment strategies in a randomized clinical trial in patients with resorbed mandibles and persistent problems with their conventional dentures: treatment with a mandibular overdenture on permucosal dental implants, an overdenture on a transmandibular implant, new dentures after preprosthetic surgery, and new dentures only. Data were gathered on an individual patient level to gain insight into specific cost episodes. Direct costs were subdivided into labor, material, technique, and overhead. Data concerning these components were gathered during the consecutive treatment phases in the first year. Results show that the resources used to treat a patient with an overdenture supported by a transmandibular implant are seven times those of a complete new set of dentures. Comparison of the cost ratio of an implant-retained overdenture supported by permucosal implants and conventional new prostheses proves less unfavorable: 1:3. New dentures after preprosthetic surgery are almost as expensive as treatment with permucosal implants.     

Clinical case report: an improved technique for using dental implants as orthodontic anchorage

The use of endosseous implants as intra-oral anchorage to facilitate orthodontic treatment has been reported in the literature for some years, first in rabbits and dogs, and then in adult human patients. The implants were generally used solely for the purpose of anchorage. This paper reports the successful application of orthodontic forces utilizing dental implants to achieve tooth movement. The implants were subsequently used as fixtures in a pre-determined plan to support a fixed prosthesis. A clinical example demonstrates how implants may serve dual roles, for anchorage and then for fixed prosthetic support. The principles involved in using dental implants as part of a multi-disciplinary approach to dental treatment are illustrated.     

Stress in bone adjacent to dental implants

Finite element analysis (FEA) was employed to assess patterns of stress in bone adjacent to an implant after application of loads through an attached distal extension cantilever. Under all loading conditions, the highest stresses occurred at the distal cervical bone margin adjacent to the cantilever. In clinical studies, this is not consistently the site of the greatest bone changes seen radiographically. This suggests that extrapolation of FEA studies to clinical implantology should be approached with caution until further data become available on both mechanical properties of bone and patterns of bone remodelling induced by defined functional stresses in mandible and maxillae.     

How to create a new profession: Issues and answers.

Proposes that a new profession is currently emerging, that of the public affairs (PAF) psychologist. There is wide latitude for the development of graduate programs with PAF objectives. The impact of the PAF emphasis on research is considered, as are the career opportunities available to the graduate of such a program. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Description and evaluation of a simplified method to achieve passive fit between cast titanium frameworks and implants

This paper deals with press-coated modified release tablets in which the drug dose is situated in the core or is divided between the core and the coat. The coat contains polymer (sodium alginate or hydroxypropylmethyl cellulose, HPMC) to control drug release. The main objective was to investigate how the pharmacokinetic profile of the model drug could be modified by altering the proportion of the drug between the core and the coat. The effect of the amount of the polymer in the coat was also studied. Bioavailability tests were carried out on healthy volunteers. In the absorption curves of the tablets containing 50%, 67% and 80% of the drug in the core and 180 mg HPMC in the coat a bimodal profile was observed. No bimodal release pattern in the in vitro dissolution studies was found. If the whole dose was incorporated in the core the absorption curve has only one clear t(max) value at about 10 h. Doubling the amount of HPMC in the coat dramatically decreased drug absorption. It was concluded that, if a slightly reduced t(max)-value was required, the viscosity grade of HPMC used should be lowered.     

Rapid bone resorption adjacent to hydroxyapatite-coated implants

This paper describes rapid bone resorption in the peri-implantitis of HA implants based on both our clinical observations of and histological research on extracted dense hydroxyapatite (HA) implants. The surfaces of extracted HA implants were rough, although they were smooth at fixture placement. Plaque formed on the necks of the implants, whereas little plaque was seen on the bottoms. The plaque consisted of cocci and rods, including filamentous bacteria. Few spirochetes were observed. Although surrounding bone was formed rapidly around the HA implant, bone thickness gradually decreased compared with the titanium implant. These facts suggest that the rigid biointegration of HA with the thin surrounding bone--that is, the overstressing of the bone--causes rapid bone resorption rather than plaque accumulation on HA.     

A new technique for performing Syed-Neblett template interstitial implants for gynecologic malignancies using transrectal-ultrasound guidance

The authors review the literature on intra-adenomatous pituitary apoplexy with special emphasis on pathophysiology, diagnosis and therapeutic approach. They present five cases, from a series of 86 patients with pituitary tumors, that developed this syndrome. The patients were diagnosed and followed by the Neurosurgery and Endocrinology Services of Hospital Universitario Clementino Fraga Filho, Universidade Federal do Rio de Janeiro. Diagnosis was confirmed by CT-Scan and MRI in all cases, and the treatment of choice was surgical. Conclusions point to the diagnostic difficulties and the urgency of treatment in this clinical setting.