Characterization method of thermomechanical parameters for microelectronic materials

Reliability of thermomechanical simulations is critically linked to the accuracy of the mechanical properties that govern the behaviour of structure, like Young's modulus (E) and coefficient of thermal expansion (CTE). For many cases, the values found in literatures are dealing with bulk properties without detailed information on temperature effects. To address such issues, it is necessary to measure the materials parameters as a function of temperature. The measurement of CTE is usually accomplished by evaluating the thermal deflections of a subjected material layer deposited on a substrate, providing that E is known at a specific temperature of experiment. A bilayer method, based on theory of elasticity, is proposed to determine both E and CTE for a given temperature with a good resolution. This paper presents the theoretical analysis, the design and process of the microsystem test structures, and the main calculation results.     

The effects of stress and crack morphology on time-of-flight diffraction signals

A model based on the theory of infinite contacting surfaces is used to analyse the transmission and reflection of ultrasound at tight fatigue cracks under compressive stress. The model developed is valid for both compression and shear (SV) waves incident at arbitrary angles on a fatigue crack and includes mode conversion effects. In discussing diffraction of ultrasound by the tips of finite length fatigue cracks, we associate the amplitude of the diffracted signal with the strength of the signal reflected from cracks of infinite extent. Thus we allow all the energy transmitted by the tight crack to play no part in the diffraction process. Comparison is made with experiments carried out at Harwell and we conclude that, for these particular experiments, the cracks are fully open when subjected to about 88 MPa of tension, and that the experimental results are consistent with a root mean square deviation from flatness of the crack faces of about 1·5 μm. This is in broad agreement with the actual crack profile when a sampling length of about 30 μm is used. Using these values the theory and experiment show excellent agreement to within 2 dB over the whole applied stress range. The results show, for example, a diffraction signal decreased by a maximum of about 13 dB when the applied compressive load corresponds to 70% of the maximum load used during crack growth. Similar conclusions are also drawn for conventional pulse-echo inspection, whereas Tandem suffers a greater reduction in signal strength due to the usually lower frequency.     

Limb salvage surgery for widely infiltrating bony sarcomas

OBJECTIVE: To determine whether neoadjuvant chemotherapy and radiotherapy for bony sarcomas extending into soft tissues would allow limb salvage yet maintain local disease control. DESIGN: A prospective cohort study. SETTING: A university-affiliated cancer centre in Alberta. PATIENTS: All patients with potentially curable, widely infiltrating bony sarcomas of the extremity without neurologic deficit, referred to the centre in the 6 years from January 1984 to December 1990. There were 11 patients; 1 did not complete the protocol. The mean follow-up was 24 months. INTERVENTIONS: Adriamycin (doxorubicin) was infused for 3 days at a rate of 30 mg/d. A few days later radiotherapy was given 5 days a week for 10 doses at a rate of 3.0 Gy per dose. Four to 5 weeks later the tumour was excised surgically, with placement of a bone allograft or prosthesis, allowing a 1-cm margin of healthy soft tissue and a 5-cm margin of healthy bone and marrow cavity whenever possible. MAIN OUTCOME MEASURES: Need for limb amputation, infectious complications, recurrence of local or regional disease. RESULTS: One patient underwent amputation after fracture through the tumour site. There were two postoperative infections, one acute and one chronic. All patients had full neurologic function of the distal limb. There was no local or regional recurrence of disease. CONCLUSION: Neoadjuvant chemotherapy followed by radiotherapy and tumour excision provides control of aggressive local bone sarcomas while maintaining limb integrity.     

1,1,2-trichloro-1,2,2-trifluoroethane for oilseed extractions: Demonstration of a viscosity effect

Extractions of full fat soy flake and meal were carried out at 5 to 70 C with hexane and 1,1,2-trichloro-l,2,2-trifluoroethane (FC-113) and their corresponding miscellas in order to evaluate FC-113 as a process solvent. In flake extraction, the rate of oil extraction by FC-113 was markedly improved with increasing temperature while extraction by hexane was relatively independent of temperature. In contrast, extraction of flake by the miscellas from both solvents and extraction of meal by fresh solvents gave similar results. A comparison of solvent properties indicates that the differences can be related to the viscosity dependent diffusion into the microporous flakes and suggests similar efficiencies for FC-113 and hexane in countercurrent flow extractors operating at elevated temperatures. Contribution No. 561 of the Research and Development Division, Jackson Laboratory, Organic Chemicals Department, E.I. du Pont de Nemours & Company, Wilmington, DE 19898     

Pattern-induced multi-sequence alignment (PUMA) algorithm employing secondary structure-dependent gap penalties for use in comparative protein modelling

A multiple sequence alignment algorithm is described that usesa dynamic programming-based pattern construction method to aligna set of homologous sequences based on their common patternof conserved sequence elements. This pattern-induced multi-sequencealignment (PUMA) algorithm can employ secondary-structure dependentgap penalties for use in comparative modelling of new sequenceswhen the three-dimensional structure of one or more membersof the same family is known. We show that the use of secondarystructure information can significantly improve the accuracyof aligning structure boundaries in a set of homologous sequenceseven when the structure of only one member of the family isknown     

Evaluation of correction factors for transmittance measurements in single-beam integrating spheres

An integrating sphere for transmittance measurements at normal and oblique angles of incidence has been constructed. The sphere is a single-beam instrument that uses a small-area silicon diode as the detector. The entry port is only 0.37% of the total wall area and has an oblong shape to permit measurements at high angles of incidence for scattering samples. A small beam size has been made possible by using a low-noise preamplifier system for the detector circuit. The oblong port shape and a small beam size make it possible to perform simulated double-beam measurements at near-normal incidence. Modified correction factors for the sample reflectance have been derived. Special attention has been paid to the separation into a diffuse and a specular component of the transmitted light. Results have been compared with the results of measurements on a double-beam instrument, and the correction factors for specular and diffuse samples have been experimentally verified. The importance of using the right correctionfactors for different types of samples has been evaluated together with the influence of the sphere parameters.     

Metrics for shot boundary detection in digital video sequences

The detection of shot boundaries in video sequences is an important task for generating indexed video databases. This paper provides a comprehensive quantitative comparison of the metrics that have been applied to shot boundary detection. In addition, several standardized statistical tests that have not been applied to this problem, as well as three new metrics, are considered. A mathematical framework for quantitatively comparing metrics is supplied. Experimental results based on a video database containing 39,000 frames are included.     

Dairy cow handling facilities and the perception of Beef Quality Assurance on Colorado dairies

A survey was conducted on Colorado dairies to assess attitudes and practices regarding Dairy Beef Quality Assurance (DBQA). The objectives were to (1) assess the need for a new handling facility that would allow all injections to be administered via DBQA standards; (2) establish if Colorado dairy producers are concerned with DBQA; and (3) assess differences in responses between dairy owners and herdsmen. Of the 95 dairies contacted, 20 (21%) agreed to participate, with a median herd size of 1,178. When asked to rank the following 7 traits—efficiency, animal safety, human safety, ease of animal handling, ease of operation, inject per Beef Quality Assurance (BQA) procedures, and cost—in order of priority when designing a new handling facility, human and animal safety were ranked highest in priority (first or second) by the majority of participants, with ease of animal handling and efficiency ranked next. Interestingly, the administration of injections per BQA standards was ranked sixth or seventh by most participants. Respondents estimated the average annual income from the sale of cull cows to be 4.6% of all dairy income, with 50% receiving at least one carcass discount or condemnation in the past 12 mo. Although almost all of the participating dairy farmers stated that the preferred injection site for medications was the neck region, a significant number admitted to using alternate injection sites. In contrast, no difference was found between responses regarding the preferred and actual location for intravenous injections. Although most participating producers are aware of BQA injection guidelines, they perceive efficiency as more important, which could result in injections being administered in locations not promoted by BQA. Dairy owners and herdsmen disagreed in whether or not workers had been injured in the animal handling area in the last 12 mo. Handling facilities that allow for an efficient and safe way to administer drugs according to BQA guidelines and educational opportunities that highlight the effect of improved DBQA on profitability could prove useful. Dairy producers play a key role in ensuring that dairy beef is safe and high quality, and just as they are committed to producing safe and nutritious milk for their customers, they should be committed to producing the best quality beef.     

Automatic Summarization of Changes in Biological Image Sequences Using Algorithmic Information Theory

An algorithmic information-theoretic method is presented for object-level summarization of meaningful changes in image sequences. Object extraction and tracking data are represented as an attributed tracking graph (ATG). Time courses of object states are compared using an adaptive information distance measure, aided by a closed-form multidimensional quantization. The notion of meaningful summarization is captured by using the gap statistic to estimate the randomness deficiency from algorithmic statistics. The summary is the clustering result and feature subset that maximize the gap statistic. This approach was validated on four bioimaging applications: 1) It was applied to a synthetic data set containing two populations of cells differing in the rate of growth, for which it correctly identified the two populations and the single feature out of 23 that separated them; 2) it was applied to 59 movies of three types of neuroprosthetic devices being inserted in the brain tissue at three speeds each, for which it correctly identified insertion speed as the primary factor affecting tissue strain; 3) when applied to movies of cultured neural progenitor cells, it correctly distinguished neurons from progenitors without requiring the use of a fixative stain; and 4) when analyzing intracellular molecular transport in cultured neurons undergoing axon specification, it automatically confirmed the role of kinesins in axon specification.     

Concordance in communication between surgeon and patient

PURPOSE: To describe adolescents' and young adults' knowledge about their health insurance, and to identify factors associated with correct knowledge of health insurance in this population. METHODS: Data were analyzed from a confidential questionnaire administered to 830 patients at a hospital-based adolescent medicine clinic. The questionnaire contained items pertaining to insurance type, demographics, health status, and health-risk behaviors. Actual health insurance data and information regarding utilization of health services were obtained from the hospital billing data-base. Predictors of health insurance knowledge were determined through bivariate analyses followed by stepwise logistic regression. RESULTS: A total of 50.7% of respondents correctly identified their type of health insurance. Those who correctly identified their insurance had a higher mean age. Only 48.5% of participants who were 11-18 years old could identify their insurance type, versus 53.1% of 19-21-year-olds and 64.7% of 22-24-year-olds (p = 0.02). Sixty-five percent of Medicaid patients and 76.3% of hospital free care patients knew how their medical bills were paid, versus 17.9% of self-pay patients and 47.3% of patients with private insurance (p < 0.01). Greater utilization of health services was associated with increased rates of insurance knowledge among 19-24-year-olds on bivariate analysis; however, this factor was not significant when controlling for other factors. Regression analysis revealed that older age and insurance type other than self-payment were independent predictors of health insurance knowledge in adolescents (11-18 years old), while female gender and insurance type other than self-payment were independent predictors of insurance knowledge in young adults (19-24 years old). CONCLUSIONS: Approximately half of adolescents and young adults do not know how their medical bills are paid. Validation of self-reported insurance data is, therefore, critical both in clinical practice and health services research.