cssi/SciSciGPT-SciSciNet huggingface dataset:
Prognostic importance of self-reported traits/problems/strengths and environmental barriers/facilitators for predicting participation outcomes in persons with traumatic brain injury: a systematic review.

Abstract Objective To conduct a systematic review of the prognostic value of self-reported traits/problems/strengths and environmental barriers/facilitators for participation outcomes in persons with traumatic brain injury (TBI). Data Sources Articles published through August 15, 2013, obtained by conducting electronic searches of PubMed, PsycINFO, and Cumulative Index to Nursing and Allied Health Literature databases and a review of reference lists of reviewed articles. Study Selection Reviewed articles were written in English and presented findings on adult humans with TBI, participation outcomes, and ≥1 self-reported trait/problem/strength (eg, depression, pain, coping style) and/or ≥1 environment barrier/facilitator (eg, social support, family functioning, access to services). Data Extraction Each of the 996 abstracts was examined by 2 reviewers, and those failing to meet all inclusion criteria were excluded. Data were extracted from the 63 retained articles by 2 independent reviewers, who met to resolve any differences in study quality rating or evidence recorded. Study quality was determined using American Academy of Neurology (AAN) criteria. Data Synthesis Conclusions regarding prognostic importance of self-report and environmental barrier/facilitator variables were made using AAN criteria. Conclusions regarding barrier/facilitator variables indicated that access to transportation, access to services, and participation in social interaction were possibly predictive of employment outcome, whereas living arrangements and social support were possibly not predictive of employment outcome. Conclusions regarding self-report variables indicated that the number of postconcussive symptoms, fatigue, and physical competence were probably predictive of employment and need for supervision, whereas self-efficacy was probably not predictive of employment. Subjective well-being, pain, and social interaction were possibly predictive of employment, whereas coping style was possibly not predictive. Conclusions Although additional investigation is needed, self-report variables are likely to make important contributions to predicting participation outcomes. Future research should be guided by coherent conceptual models and use a consistent set of assessment instruments to facilitate comparisons between studies.
Prediction of heat transfer in prototype fluidized reactors from scale-model data

The goal of this research was to predict heat transfer in a prototype fluidized bed from data obtained in a hydrodynamically scaled model bed. Experimental heat transfer data measured in the model bed (45 mm diameter) was used in conjunction with simple, mathematical models to deduce particle residence time in the model bed. Residence time for the prototype bed (95 mm diameter) was estimated by scaling model bed residence times. This data, in turn, was used to predict heat transfer in the prototype bed. This methodology yielded predictions that are within 15% of experimental data obtained in the prototype bed. Particle properties were varied by using steel and bismuth while gas properties were varied by using nitrogen and carbon dioxide.
Surface-enhanced Raman spectroscopy of pyridine derivatives: Effects of adsorption on electronic structure

Abstract The surface-enhanced Raman (SER) spectra of 2-, 3-, and 4-pyridinecarboxaldehydes, methylketones and 3- and 4-carbinols are compared with the spectra of the neat compounds and aqueous solutions, and effects of the adsorbate-substrate interactions which occur when these molecules are adsorbed on silver electrodes are identified. The 4-substituted carboxaldehyde and methylketone exhibit weaker carbonyl stretching bands when adsorbed on silver than in solution, while no such effect is found for the corresponding 3-substituted compounds. This is consistent with an interaction of the nitrogen lone-pair electrons with the silver, leading to electron withdrawal from 4-substituents and increased hydration of carbonyl groups at that position. Examination of solution spectra of the N-methylpyridinium salts shows a similar trend, with N-methylation increasing hydration and reducing the carbonyl band intensity in N-methyl-4-pyridiniumcarboxaldehyde but not in N-methyl-3-pyridiniumcarboxaldehyde. The surface-enhanced spectrum of 4-pyridinecarboxaldehyde is identical to that of 4-pyridylcarbinol, indicating that the aldehyde is completely hydrated on the electrode. Thus SER spectroscopy allows identification of a surface species which is quite different from that found in bulk solution. The reduction potentials of the pyridinecarboxaldehydes and methylketones are determined to show that no electrochemical reductions take place at the potentials used.
The impact of land-applied incinerator ash residue on a freshwater wetland plant community

In 1977, 60–70 tonnes of incinerator ash residue were deposited adjacent to a freshwater wetland. These residues are known to contain elevated concentrations of soluble cations and toxic elements. The impact on the wetland plant community was monitored over a 6-year period. Changes in species abundance and diversity were assessed both over time and distance from the residue deposition. A methodology from the marine benthic pollution literature was used to identify possible indicator species from the group of moderately adapted plants. Distance from the residue did not account for the overall increase in community richness, but appeared to be a factor in the increased relative abundance of moderately adapted species near the residue site, as a result of decreased relative abundance of dominant species. Acute phytotoxic effects were undetected, with the possible exception of the decline of Asclepia syriaca (milkweed). Post-experiment soil analyses indicated an increase of Ca, Mn, P, Zn and Cd in wetland soils near the residue site and an even greater increase in P, K, Ca, Mg, B, Zn, Cu, Mn, Al, Cd and Pb in the soil directly beneath the residue. If residue landfills are not properly designed or maintained, the cumulative impact of daily residue deposition could eventually disrupt sensitive ecosystems and pollute adjacent soils and groundwater.
Compactification of the discrete state space of a Markov process

The countable state space of a Markov chain whose stationary transition probabilities satisfy the continuity condition (1.5) is compactifled to get a state space on which the corresponding processes can be made right continuous with left limits, and strongly Markovian. There is a form of quasi left continuity, modified by the possible presence of branch points. Excessive functions are investigated.
RAPID COMPUTATION OF THE RADIATIVE ABSORPTION RATE IN THE v3 MODE OF MESOSPHERIC AND LOWER THERMOSPHERIC OZONE

An algorithm has been developed to calculate rapidly and accurately the rate at which the ozone nu3 fundamental band absorbs IR radiation in the terrestrial upper mesosphere and lower thermosphere. Accurate knowledge of this rate is essential for studies of non-LTE processes in ozone and for estimating ozone concentrations from measurements of non-LTE IR emission from the middle atmosphere. In the algorithm, the 1252 ozone nu3 fundamental lines that govern radiative absorption are divided into 13 groups according to line strength. The absorption rate due to a single line representative of the mean line strength of each group is then calculated. The total absorption rate is obtained by multiplying the absorption rate for each mean line by the total number of lines within each group and adding the resultant products for all 13 groups.
Cellulitis and coronary artery bypass surgery.

Excerpt To the editor: Two articles in the November issue (1, 2) described 14 patients with recurrent cellulitis after coronary artery bypass surgery. We report the case of an additional patient, w...
Factors related to driving difficulty and habits in older drivers.

Objectives: To evaluate the association between chronic medical conditions, functional, cognitive, and visual impairments and driving difficulty and habits among older drivers. Design: Cross-sectional study. Setting: Mobile County, Alabama. Participants: A total of 901 residents of Mobile County, Alabama aged 65 or older who possessed a driver's license in 1996. Measurements: Information on demographic characteristics, functional limitations, chronic medical conditions, driving habits, and visual and cognitive function were collected via telephone. The three dependent variables in this study were difficulty with driving, defined as any reported difficulty in ≥3 driving situations (e.g. at night), low annual estimated mileage, defined as driving less than 3000 miles in 1996, and low number of days (≤3) driven per week. Results: A history of falls, kidney disease or stroke was associated with difficulty driving. Older drivers with a history of kidney disease were more likely to report a low annual mileage than subjects without kidney disease. Low annual mileage was also associated with cognitive impairment. In general, older drivers with a functional impairment were more likely to drive less than 4 days per week. Older drivers with a history of cataracts or high blood pressure were more likely to report a low number of days driven per week, while subjects with visual impairment were at increased risk of experiencing difficulty driving as well as low number of days driven per week. Conclusions: The results underscore the need to further understand the factors negatively affecting driving independence and mobility in older drivers, as well as the importance of improved communication between older adults and health care professionals regarding driving.
Expression of glutathione S-transferases in poplar trees (Populus trichocarpa) exposed to 2,4,6-trinitrotoluene (TNT)

Abstract Twelve Populus genes were identified from Arabidopsis thaliana sequences previously shown to be induced by exposure to 2,4,6-trinitrotoluene (TNT). Using the resources of the Poplar Genome Project and National Center for Biotechnology Information databases, Populus conserved domains were identified and used to design gene specific primers. RNA extracted from root tissues of TNT-exposed hydroponic poplar plants was used to quantify the expression of genes by reverse-transcriptase real-time polymerase chain reaction. Cyclophilin and 18S ribosomal DNA genes were used as internal standards. Exposure to TNT resulted in a significant increase of gene expression of two glutathione S-transferases (GST), peaking at levels of 25.0 ± 13.1 and 10 ± 0.7 fold the expression level of non-exposed plants after 24 h for each of the GST genes, respectively. This paper demonstrates the use of functional genomics information from the model plant species, Arabidopsis, to identify genes which may be important in detoxification of TNT in the model phytoremediation species, Populus trichocarpa.
Chemically induced potential barriers at the carbon nanotube-metal nanoparticle interface.

Single-walled carbon nanotube (SWNT) field effect transistors were electrochemically decorated with Pt, Pd, Au, and Ag nanoparticles. Upon exposure to 10 ppm NO gas in N2 a trend was found wherein the magnitude of electron transfer into the SWNT valence band scaled with the work function of the individual metal. This trend gives experimental support for the formation of a metal work function dependent potential barrier at the SWNT−nanoparticle interface.
The Effect of Interfacial Polarization on the Energy Density of Ferroelectric Glass-Ceramics

In the last two years, the US Naval Research Laboratory has been able to synthesize barium strontium titanate (BST)-based glass-ceramics with dielectric breakdown strength as high as 800 kV/cm and dielectric constant up to 1200. Unfortunately, the energy density of the candidate glass-ceramics was only ~1 joule/cc when measured using a discharge measurement circuit. Polarization-electric field measurements revealed wide open hysteresis loops, indicating that most of the electrical energy was not released during discharge. Subsequent experiments showed that the buildup of interfacial polarization was the likely cause in this composite dielectric system. Using the Maxwell-Wagner capacitor model, we were able to quantify the dielectric response of composites based on the permittivities and conductivities of the constituent phases. The response was used to plot polarization-electric field hysteresis for energy density predictions. The results indicated that the aluminosilicate glass phase is the major contributor to the interfacial polarization in this glass-ceramic system.
Bringing forth worlds

Abstract Kress encourages us to understand writing as “transformative engagement in the world,” and his emphasis on the materiality of modes draws our attention to the multiple possibilities offered by different materials and sensory channels. Writing involves the transformation of all aspects of the resources for meaning; thus writing is always an ethical act, and the worlds that different cultures and communities bring forth through their semiotic work offer different possibilities of being.
Effect of vitamin E, selenium and age on lipid peroxidation events in rat cerebrum

Abstract The effect of 8 and 20 weeks of dietary vitamin E (200 IU/kg diet) and/or selenium (0.2 ppm) supplementation or deficiency on oxidative processes in cerebrum of 1 and 15 month old male F344 rats was examined. After 8 weeks of treatment a 32-fold difference in plasma and a 3-fold difference in cerebrum alpha-tocopherol (a-T) level was found between vitamin E supplemented and deficient young rats. These differences were 1.8- and 1.5-fold, respectively, in old rats and increased to 8- and 2-fold differences, respectively, after an additional 12 weeks of treatment. Selenium deficiency had a significant effect on plasma glutathione peroxidase activity and a slight sparing effect on plasma a-T content. Endogenous lipid peroxides (thiobarbituric acid reactants present without incubation) in cerebrum were not correlated with a-T concentration or age. However, incubation of cerebrum homogenates with or without the addition of 0.1 mM Fe 2+ , 0.25 mM ascorbic acid, or 100 mg % acetaldehyde revealed that dietary vitamin E has a major role and selenium has a minor role in the protection against ex-vivo and possibly in vivo lipid peroxidation in cerebrum.
Youth violence and connectedness in adolescence: What are the implications for later sexually transmitted infections?

Abstract Purpose To examine associations between (1) youth violence victimization and perpetration and later sexually transmitted infections (STI) and (2) parent–family and school connectedness and later STI, and to explore the moderating role of connectedness on the associations between youth violence victimization and perpetration and later STI. Methods We used data from Waves I and IV of the National Longitudinal Study of Adolescent Health, which provided a baseline weighted sample of 14,800 respondents. We used logistic regression to examine associations between youth violence and connectedness with self-reported ever STI diagnosis, including gonorrhea, chlamydia, syphilis, genital herpes, genital warts or human papillomavirus, or human immunodeficiency virus. If participants reported having an STI at Wave I they were excluded from the analysis. Results Controlling for biological sex, race/ethnicity, age, parent's highest education level, and parent's marital status, both youth violence victimization and perpetration were associated with an increased risk of later STI (adjusted odds ratio [AOR], 1.27, 95% confidence interval [CI], 1.07–1.52; and AOR, 1.21, 95% CI, 1.04–1.41, respectively). Parent–family and school connectedness in adolescence were associated with a decreased risk for later STI (AOR, .96, 95% CI, .95–.98; and AOR, .97, 95% CI, .95–.99, respectively); however, connectedness did not moderate the associations between nonsexual violence involvement and later STI. Conclusions These results indicate that youth violence victimization and perpetration may be risk factors for STI later in life. Conversely, parent–family and school connectedness in adolescence appear to protect against subsequent STI. The findings suggest that provider efforts to address youth violence and connectedness in adolescence can promote positive sexual health outcomes in adulthood.
Isolation of discrete repetitive sequence classes from Xenopus DNA by high temperature reassociation

Sequences that did or did not reassociate at 75 dagrees C (stable and unstable, respectively) were isolated from total repetitive Xenopus laevis DNA. Sequence complexities or frequencies were determined by self (minicot) or DNA excess (slave minicot) reassociations at 60 degrees C. Stable sequences were five times shorter and four times more frequent than unstable sequences. Reassociations at 75 degrees C or at 50 degrees C were used to establish apparent sequence frequencies at these criteria. Interspersion curves at either 60 degrees C or 75 degrees C and low Cot reassociation of long fragments of total X. laevis DNA at either 60 degrees C or 75 degrees C, followed by S1 digestion and agarose chromatography, were used to determine genome arrangement of the stable and unstable classes of sequence. Reassociation at high temperature was found to permit the fractionation of repetitive sequences into two populations of differing characteristics.
Voltammetric Characterization of Ruthenium Oxide-Based Aerogels and Other RuO2 Solids: The Nature of Capacitance in Nanostructured Materials

Ruthenium dioxide is an important electrode material for applications in electrocatalysis and power sources. High surface areas are achieved in hydrous RuO2 precipitates and in mixed ruthenium oxide−titanium oxide, (Ru−Ti)Ox, aerogels (in which nanoscale domains are networked to form a highly porous structure). The electrochemical properties of (Ru−Ti)Ox aerogels, RuO2, and hydrous RuO2 are examined by direct pressing of sub-milligram quantities of the solid onto the surface of a conductive carbon/wax composite. Voltammetric measurements in acidic electrolyte confirm a pseudocapacitive response for all the RuOx-based materials. Despite an improvement in BET surface area, as compared with other RuO2 materials, the (Ru−Ti)Ox aerogel displays a low specific capacitance, which correlates to the high degree of crystallinity of the aerogel. Nanocrystallites of rutile RuO2, formed during thermal treatment of the sol−gel Ru/Ti precursors, deleteriously affect the specific capacitance of the material; however, all...
Isolated swine heart ventricle perfusion model for implant assisted-magnetic drug targeting.

An isolated swine heart ventricle perfusion model was developed and used under physiologically relevant conditions to study implant assisted-magnetic drug targeting (IA-MDT). A stent coil was fabricated from a ferromagnetic SS 430 wire and used to capture 100-nm diameter magnetite particles that mimicked magnetic drug carrier particles (MDCPs). Four key cases were studied: (1) no stent and no magnet (control), (2) no magnet but with a stent, (3) no stent but with a magnet (traditional MDT), and (4) with a stent and a magnet (IA-MDT). When applied, the magnetic field was fixed at 0.125 T. The performance of the system was based on the capture efficiency (CE) of the magnetite nanoparticles. The experiments done in the absence of the magnetic field showed minimal retention of any nanoparticles whether the stent was present or not. The experiments done in the presence of the magnetic field showed a statistically significant increase in the retention of the nanoparticles, with a marked difference between the traditional and IA-MDT cases. Compared to the control case, in one case there was nearly an 11-fold increase in CE for the IA-MDT case compared to only a threefold increase in CE for the traditional MDT case. This enhanced performance by the IA-MDT case was typical of all the experiments. Histology images of the cross-section of the coronary artery revealed that the nanoparticles were captured mainly in the vicinity of the stent. Overall, the IA-MDT results from this work with actual tissue were very encouraging and similar to those obtained from other non-tissue and theoretical studies; but, they did point to the need for further studies of IA-MDT.
Effects of Age and Marital Status on Emotional Distress after a Mastectomy

Although a large body of empirical literature exists on the psychosocial consequences of breast cancer and its treatment, scant attention has been paid to how various social characteristics affect adjustment after a mastectomy. In the research described in this article, regression analysis was used to assess how marital status affects the emotional recovery of mastectomy patients of different ages. Socioeconomic status, employment, and parental status were used as controls to permit a clearer understanding of how marital status affected women coping with this life crisis. Interviews conducted in 1979 with 652 women who underwent a mastectomy one year earlier revealed that although younger women are more likely to fear recurrence of the disease and to worry about disfigurement resulting from surgery, they apparently have resources that protect them against depression. Being married, generally believed to be a buffer against stressful life events, affords limited protection at best: Nevermarried women are s...
Mother-daughter dominance reversals in rhesus monkeys (Macaca mulatta)

The dominance relations in a newly formed group of rhesus monkeys were monitored routinely for eight years, using as an indicator of relative rank the outcome of dyadic aggressive encounters. These compound-living animals exhibited a stable linear dominance order, with male and female juveniles assuming ranks just below their mothers. In contrast to previous observations, each of the nine females whose first-born was a daughter was bypassed in rank by one or more of her daughters in the daughter's menarchal year. These changes in status have remained stable and are considered permanent. A brief description of a typical rank reversal sequence is provided.
Approximating high dimensional probability distributions

We present an approach to estimating high dimensional discrete probability distributions with decomposable graphical models. Starting with the independence assumption we add edges and thus gradually increase the complexity of our model. Bounded by the minimum description length principle we are able to produce highly accurate models without overfitting. We discuss the properties and benefits of this approach in an experimental evaluation and compare it to the well-studied Chow-Liu algorithm.
Lattice Boltzmann modeling of buoyant rise of single and multiple bubbles

Abstract Buoyant rise of bubbles is investigated using the lattice Boltzmann method (LBM) based Gunstensen’s color model. An external force/sink term is incorporated in the collision step to simulate buoyant rise of bubbles under gravitational force. The shape of a bubble is controlled by inertial, viscous and surface tension forces. The interplay between these forces is quantified using non-dimensional numbers such as Eotvos number (Eo), Morton number (Mo) and Reynolds number (Re). A set of results from numerical simulations are presented to demonstrate the ability of the proposed approach to simulate rise of single and multiple bubbles under buoyancy. The proposed modification is verified by comparing terminal velocity of bubbles in an infinite medium against the analytical solution. The shape of bubbles in various flow regimes characterized by the non-dimensional numbers is compared against the experimental data. The effect of surface tension and viscosity ratio on terminal velocity and shape of bubbles is investigated. The LBM results for topological change in the shape of bubbles or circularity of bubbles is compared against COMSOL. Co-axial and oblique coalescence of two gas bubbles are simulated and compared against the experimental data. The simulation results from LBM simulations were found to be in good agreement with the analytical solution, the experimental data and the COMSOL simulation.
Structural Demonstration of the Role of Ligand Framework Conformability in Copper(II)/Copper(I) Redox Potentials

Two macrocyclic CuN2S2 complexes are described. In the larger (16-membered) macrocycle, a butylene linkage allows the ligand to accommodate the pseudotetrahedral geometry of the copper(I) form, thus elevating the CuII/CuI E1/2 value in comparison with the 15-membered ring's complex. This is the first crystallographic demonstration of this flexibility factor.
Mechanical stimulation device for skeletal muscle tissue engineering

The goal of this project is to create an accurate model for skeletal muscle in vitro, with a specific focus to enable mechanical stimulation of the tissue. The project began by creating a list of functions, objectives, and constraints based upon a client needs statement. Conceptual designs were then brainstormed and tested for feasibility in order to select components of final design. The design is currently in assembly and testing phases including testing with skeletal muscle tissue formation.
HOMA-beta in the UKPDS and ADOPT. Is the natural history of type 2 diabetes characterised by a progressive and inexorable loss of insulin secretory function? Maybe? Maybe not?

Introduction In 1995 the investigators of the United Kingdom Prospective Diabetes Study (UKPDS) published the results of 6 years of therapy with a variety of blood glucose-lowering drugs in patients with 2DM. Although the major goal of the study was to evaluate the relationship between glycaemic control and the development of diabetic complications, the report contained metabolic data which have had a substantial impact on general views as to the pathophysiology of 2DM. Specifically, using HOMA-beta, a surrogate estimate of pancreatic beta-cell function based on measurements of fasting plasma glucose and insulin concentrations, it was concluded that approximately 50% of insulin secretory capacity had been lost in these patients prior to initiation of the study. Following enrolment, there was a progressive deterioration of glycaemic control over the next 6 years in all groups, including those assigned to ‘intensive’ glycaemic intervention. beta-cell function as estimated by HOMA-beta also decreased continuously over the study period, leading the authors to conclude that ‘progressively increasing hyperglycaemia, associated with decreasing beta-cell function, was a marked feature irrespective of the therapy used.’ HOMA-beta has continued to be used as an estimate of beta-cell function in the years following the publication of the UKPDS report, with essentially similar conclusions as to the progressive loss of insulin secretory function over the natural history of 2DM. For example, HOMA-beta was used in the recent study 3 A Diabetes Outcome Progression Trial (ADOPT) to assess changes in beta-cell function over time in patients with 2DM assigned to monotherapy with rosiglitazone, metformin or glyburide. The major conclusion of ADOPT was that although the three drugs differed in length of time for monotherapy to fail, the data were consistent with the UKPDS results in that the initial improvement in glycaemic control was followed by a progressive increase in glycated haemoglobin and fasting plasma glucose concentration. The effect of treatment on the estimate of beta-cell function was somewhat more complicated than reported by the UKPDS, consisting of an initial improvement following initiation of drug treatment, but after this ‘levels of beta-cell function declined in all three groups.’ The notion of a progressive and inexorable loss of beta-cell function as part of the natural history of 2DM has been buttressed by results suggesting that in order to attain glycaemic control in patients with 2DM over time additional pharmacological agents must continually be added. This point was initially made in one of the reports of the UKPDS, but is echoed in the findings of the ADOPT study. The remainder of this analysis will be devoted to consideration of the appropriateness of HOMA-beta as an assessment of insulin secretory function, as well as the notion that glycaemic control inexorably declines with duration of 2DM.
Effects of Time-Compression on Feature and Frequency Discrimination in Aged Listeners:

This study measured the ability of 16 aged listeners, normal for their age (age range, 63 to 84 yr.) to discriminate phonemic contrasts in sentential stimuli (Subtest 13 of the Carrow-Auditory Visual Abilities Test) presented at 50% time-compression rate. A series of linear regression analyses were performed in which each independent variable was regressed against the continuous variable of age. Over-all performance on the time-compressed task significantly decreased as a function of age. Also discrimination of place of articulation and mid- to high-frequency contrasts was significantly and negatively related to age. In general, such findings suggest that the course of aging continuously imposes degrading effects on speech-processing that are related to discrimination of place feature contrasts. Language: en
Effects of the obese gene product on body weight regulation in ob/ob mice

C57BL/6J mice with a mutation in the obese (ob) gene are obese, diabetic, and exhibit reduced activity, metabolism, and body temperature. Daily intraperitoneal injection of these mice with recombinant OB protein lowered their body weight, percent body fat, food intake, and serum concentrations of glucose and insulin. In addition, metabolic rate, body temperature, and activity levels were increased by this treatment. None of these parameters was altered beyond the level observed in lean controls, suggesting that the OB protein normalized the metabolic status of the ob/ob mice. Lean animals injected with OB protein maintained a smaller weight loss throughout the 28-day study and showed no changes in any of the metabolic parameters. These data suggest that the OB protein regulates body weight and fat deposition through effects on metabolism and appetite.
Projected structure of purple membrane determined to 3.7 A resolution by low temperature electron microscopy.

Abstract The projected structure of the purple membrane has been determined to 3·7 A resolution by low dose electron imaging and diffraction. The specimens were maintained at low temperature in order to minimize the effects of radiation damage. To obtain phases at high resolution, a treatment of errors in electron imaging has been developed that makes possible the systematic combination of data from several image areas. This treatment is analogous to that used in protein crystallography for phase determination by multiple isomorphous replacement. Phase probability distributions are calculated for each reflection, and distributions from many sets of image data are combined. The use of probability distributions allows such factors as image motion, defocus, defocus uncertainty and image degradation to be taken into account in the weighting of data from individual image areas. Centroid phases and figures of merit are computed, allowing the map with the least-squares error in electron scattering potential to be synthesized from the combined data.
Curve fitting in nuclear magnetic resonance spectroscopy: Illustrative examples using a spreadsheet and microcomputer

A simplified explanation of the modified Gauss-Newton linearization (curve-fitting) procedure is presented by translating this algorithm into a spreadsheet with examples from various single- and multiple-pulse NMR experiments. Comparisons are made with linear regression analysis of mathematically manipulated data.
Blocking out reengineering's evolution. A long-distance jump shot

The fundamental shift in managerial philosophy is behind the waves of delayering, reengineering and empowerment sweeping across today's organization. Rather than managing through abstractions of plans and controls, top-level managers are recognizing that their key task is to create a work environment that stimulates the company's valuable human resource to be more motivated, creative and entrepreneurial than its competitors' employees. Only when they liberate and motivate their people to develop and leverage their knowledge and expertise will they have created a dynamic, self-renewing corporation.
Nature of sediment accumulation on the Amazon continental shelf

Sediment accumulation on the Brazilian continental shelf near the Amazon River is investigated using radiochemical (e.g.210Pb,14C) techniques to provide a better understanding of this major dispersal system of fine-grained sediment.210Pb profiles from 57 cores collected during 1983 reveal the distribution of modern (100-y time scale) accumulation rates on the Amazon subaqueous delta. Accumulation rates increase from 100 y) sediment in the northwestern portion of the subaqueous delta indicates that this sediment was deposited <1000 y ago. The absence of modern sediment in this area is not understood. A sediment budget for the Amazon shelf indicates that 6.3 ± 2.0 × 108 tons of sediment accumulate annually. Much of the remainder of Amazon River sediment (∼6 × 108tons y−1) probably is transported northwestward beyond the Brazilian shelf and/or is accumulating landward of the shelf as coastal accretion.
Impairment of antigen-specific T-cell priming in mice lacking CD40 ligand.

LACK of functional expression of CD40 ligand (CD40L) on T cells results in hyper-IgM syndrome (HIGMl), a human immunodeficiency associated with a severely impaired humoral immune response that is consistent with defects in B-cell responses1–3. Patients also succumb to recurrent opportunistic infections such as Pneumocystis carinii and Cryptosporidial diarrhoea4,5, suggesting that T-cell functions are also compromised in these individuals, but so far this has not been explained. We have previously shown that mice deficient for CD40L, like HIGMl patients, show grossly abnormal humoral responses6. Here we report that CD40L-deficient mice are defective in antigen-specific T-cell responses. Adoptively transferred antigen-specific CD4+ T cells lacking CD40L failed to expand upon antigen challenge of the recipients, showing that expression of CD40L on T cells is required for in vivo priming of CD4+ T cells and therefore for the initiation of specific T-cell immune responses.
Evaluating flood retarding structures

Abstract An empirical relation between volume and peak of runoff (VPR) was utilized to determine peak discharge reduction effectiveness of flood retarding structures. The effectiveness was evaluated by comparing the predam VPR relation with and a pre and post dam channel length frequency distribution (CLFD) for the point of interest. The procedure involved well related hydrologic and geomorphic variables and thus could be a practical prediction tool.
Fusion solution to dispose of spent nuclear fuel, transuranic elements, and highly enriched uranium

Abstract The disposal of the nuclear spent fuel, the transuranic elements, and the highly enriched uranium represents a major problem under investigation by the international scientific community to identify the most promising solutions. The investigation of this paper focused on achieving the top rated solution for the problem, the elimination goal, which requires complete elimination for the transuranic elements or the highly enriched uranium, and the long-lived fission products. To achieve this goal, fusion blankets with liquid carrier, molten salts or liquid metal eutectics, for the transuranic elements and the uranium isotopes are utilized. The generated energy from the fusion blankets is used to provide revenue for the system. The long-lived fission products are fabricated into fission product targets for transmutation utilizing the neutron leakage from the fusion blankets. This paper investigated the fusion blanket designs for small fusion devices and the system requirements for such application. The results show that 334 MW of fusion power from D–T plasma for 30 years with an availability factor of 0.75 can dispose of the 70,000 tons of the U.S. inventory of spent nuclear fuel generated up to the year 2015. In addition, this fusion solution eliminates the need for a geological repository site, which is a major advantage. Meanwhile, such utilization of the fusion power will provide an excellent opportunity to develop fusion energy for the future.
Proton and phosphorous MR spectroscopy in squamous cell carcinomas of the head and neck.

Rationale and Objectives Phosphorous magnetic resonance spectroscopy (31P MRS) has been used to evaluate and predict treatment response in squamous cell carcinoma of the head and neck (HNSCC). Several studies have also shown the potential of proton MRS (1H MRS) in assessing response in HNSCC. In view of the inherent limitations associated with performing 31P MRS in clinical settings, the current study was performed to explore whether 1H MRS could provide similar or complementary metabolic information in HNSCC. Materials and Methods Fifteen patients with HNSCC underwent pretreatment magnetic resonance imaging. Both 1H MRS and 31P MRS were performed on viable solid parts of the metastatic lymph nodes of these patients. Peak areas of total choline (tCho) and unsuppressed water as observed on 1H MRS and phosphomonoester (PME) and β-nucleotide triphosphate (β-NTP) on 31P MRS were computed. Pearson's correlation coefficient was used to correlate the tCho/water and PME/β-NTP ratios. Results In all patients, the metastatic nodes appeared hyperintense on T2-weighted images and hypointense on T1-weighted images with variable signal intensity. A prominent resonance of tCho on 1H MRS and a resonance of PME on 31P MRS from the metastatic nodes of all patients were observed. A moderate correlation of 0.31 was observed between tCho/water and PME/β-NTP (P > .05). Conclusions The biochemical pathways involved in 1H MRS of tCho may be different from the phospholipid metabolites seen on 31P MRS of head and neck cancers, and thus the two MRS techniques may be complementary to each other.
Heat shock factor 1 contains two functional domains that mediate transcriptional repression of the c-fos and c-fms genes.

Heat shock factor 1 (HSF1), in addition to its pivotal role as a regulator of the heat shock response, functions as a versatile gene repressor. We have investigated the structural domains involved in gene repression using mutational analysis of thehsf1 gene. Our studies indicate that HSF1 contains two adjacent sequences located within the N-terminal half of the protein that mediate the repression of c-fos and c-fms. One region (NF) appears to be involved in quenching transcriptional activation factors on target promoters and binds to the basic zipper transcription factor NF-IL6 required for activation of c-fms and IL-1β. The NF domain encompasses the leucine zipper 1 and 2 sequences as well as the linker domain between the DNA binding and leucine zipper regions. The function of this domain in gene repression is highly specific for HSF1, and the homologous region from conserved family member HSF2 does not restore repressive function in HSF2/HSF1 chimeras. In addition, HSF2 is not capable of binding to NF-IL6. The NF domain, although necessary for repression, is not sufficient, and a second region (REP) occupying a portion of the regulatory domain is required for repression. Neither domain functions independently, and both are required for repression. Furthermore, we constructed dominant inhibitors of c-fos repression by HSF1, which also blocked the repression of c-fms and IL-1β, suggesting a shared mechanism for repression of these genes by HSF1. Our studies suggest a complex mechanism for gene repression by HSF1 involving the binding to and quenching of activating factors on target promoters. Mapping the structural domains involved in this process should permit further characterization of molecular mechanisms that mediate repression.
Submicron structures--promising filters in EUV: a review

A novel, fledgling approach to the filtering of EUV radiation for laboratory and space applications is reviewed. Foils perforated by a set of parallel channels with submicron diameters serve as wavelength-dependent filters. Each channel passes photons when the wavelength is much smaller than the channel diameter. The transmission of the channel drops dramatically, however, when the wavelength becomes comparable to or larger than the channel diameter. The relevant theoretical considerations as well as available experimental data are presented. Several different ways to manufacture such kind of filters are outlined, including nuclear track filters, anodized metal films, and microchannel plate technology. Advantages and disadvantages of each technique are discussed. The history of the work in the field as well as prospects for the future are presented.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Individualized matrix bands for amalgam restorations.

A l t h o u g h various patented matrices have claimed "universal application," no one matrix appears to be truly universal. When properly applied, these matrices can be useful. However, they do have limitations: Placement is possible only from the buccal side; wedging at the gingivaI margin is difficult; use is limited to Class II restorations; and projecting handles interfere when inserting adjacent amalgam restorations. This paper will describe the fabrication and utilization of the indivualized, spotwelded, continuous-loop matrix, which is relatively simple to construct and which gives consistently excellent results. It employs materials present in most dental offices and has the added advantage of easy application for multiple, contiguous, amalgam restorations. Black 1 described a ligated matrix band of "very thin stainless steel," adapted gingivalty by ligature and held in place by either a contoured orangewood stick or by the Ferrier separator. Hollenback ~used Black's matrix encircled with low-fusing compound. In 1940, Sweeney "~ described a matrix using 0.002 untempered steel matrix material, contoured to extend beyond tile gingival margin of the cavity preparation and 1 ham. above the adjacent marginal ridge. A contoured interproximal wedge of tongue blade was moistened and placed at the gingival margin. Tile matrix was stabilized with low-fusing compound, followed by pressing the warmed jaws of an Ivor 7 No. 1 matrix retainer into the compound. Ingraham and Koser 4 described the anatomic matrix (known also as tile modified Sweeney matrix) in 1955. Stabilization was achieved by use of a heated wire staple forced into the compound until it contacted the adjacent marginal ridge. The contact area was burnished with a warmed ball burnisher. Green, Shellman, and Simon '~ reviewed several matrices. They recognized that MOD or other complex cavity preparations may present problems too difficult for patented matrices.
Coherency strain-induced ordering in substitutional alloys

It has been well known that one of the driving forces for ordering is the relaxation of elastic strain energy due to difference in atomic size, a clear evidence being the change in lattice parameter between ordered and disordered states. Because of mathematical complexity, however, only a few strain models have been presented for substitutional alloys. This work reports coherency-induced ordering in a simple model with a two-dimensional square lattice. At an equi-atom composition, a square lattice displays two elementary, ordered structures, Sl0 and S11, similar to Ll1(CuAuI) and L11 (CuPt) in fcc. The stability of two superlattices at the ground state depends strongly on elastic anisotropy. For a homogeneous system, Zener’s anisotropy ratio is sufficient to measure the stability of one structure against the other. If the elastic constants are different, however, the stability depends not only on the elastic moduli of both elements but also on the solvent-solute bond length. The order-to-disorder transition is studied via the Discrete Atom Method, which is predicated upon statistical mechanics and linear elasticity. When both elastic and chemical interactions join together for ordering, the transition temperature is raised to a value greater than the sum of the two individual cases-an indication of a coupling between the two driving forces.
Resistance to EGFR-Targeted Therapy: A Family Affair

The EGFR-directed antibody cetuximab has proven, albeit modest, clinical benefit as monotherapy in head and neck and colorectal cancers. In a recent study, Yonesaka et al. uncovered a new mechanism of cetuximab resistance mediated by increased ERBB2 signaling via amplification of ERBB2 or increased levels of the ERBB3/ERBB4 ligand heregulin.
The metabolic and immune response to laparoscopic vs open liver resection

Background Laparoscopic liver surgery is a field in its infancy, and scientific evidence of its benefits over those of traditional open techniques has not been shown. Various applications from wedge resections to formal segmental resections have been reported, but the technical ability does not necessarily translate into improved patient outcomes. There is an abundance of evidence reflecting the benefits of laparoscopic cholecystectomy [9, 12, 23], and some of these benefits have been linked to the decreased metabolic and immune responses involved [24, 27]. There is also accumulating evidence that tumor growth may be slower after laparoscopic surgery than after comparable open surgery, and that this is a result of less immune suppression [1]. It is not known whether laparoscopic liver surgery will convey similar benefits.
Spurious associations in oral epidemiological research: the case of dental flossing and obesity

Background Individuals with increased oral health awareness may also have increased general health awareness, and vice versa. Such associations between oral and general health awareness has the potential to induce spurious associations in oral epidemiological research. Objective To assess the extent to which oral self-care patterns and general health awareness are confounded, we investigated the association between flossing and obesity, two lifestyle factors that are unlikely to be causally related. Methods A cross-sectional study of 1497 individuals presenting for an initial periodontal exam by the specialist. Self-reported flossing behaviors and body mass index (BMI) categories were related using logistic regression models. Results After adjustment for confounding variables, lack of daily flossing was associated in a dose-dependent way with morbid obesity (odds ratio (OR), 20.3; 95% confidence interval (CI), 2.7-154.0), obesity (OR, 2.1; 95% CI, 1.5-2.9), and being overweight (OR, 1.7; 95% CI, 1.3-2.2). When restricting to never smokers, a significant relationship between obesity and lack of flossing remained. Conclusion The strong associations between two causally unrelated oral and general lifestyle characteristics indicate that simplistic epidemiologic methodology is unlikely to provide insights into causal mechanisms of oral diseases or oral-systemic relationships.
Long-Term Determinants of Patterns of Health Insurance Coverage in the Medicare Population

Using data from the 1990 Health Supplement to the Panel Study of Income Dynamics, we examine the determinants of patterns of insurance coverage among the elderly. Among those with supplemental insurance through an employment-based source, the primary determinant of having insurance is work history, specifically job tenure and occupation of household heads and their spouses. Among those who do not have employer-provided insurance, wealth is the most important economic factor in the purchase of private insurance. Blacks, persons with less education and women household heads are less likely to purchase supplemental insurance. We find little evidence that persons in prior poor health are more likely to purchase supplemental insurance, and the most important determinant of dental or drug coverage is having employer-based insurance. The current trend toward decreased generosity of post-retirement benefits implies that fewer older Americans will have insurance for these services.