cssi/SciSciGPT-SciSciNet huggingface dataset:
Large Torsional Oscillations in Suspension Bridges Revisited: Fixing an Old Approximation

Good historical sources for these behaviours are [2] and [5]. Of course, these behaviours strongly suggest nonlinearity, and in the late eighties, following recent and rapid progress in nonlinear analysis of boundary value problems that had just been taking place, I and co-workers attempted to give a mathematical explanation for these phenomena [13], [16-19]. Our starting point was that an unloaded cable cannot be described by the usual Hooke's law, since it resists expansion but not compression. Thus if an unloaded cable is expanded downward by a distance u from the unloaded state, the cable should have a resisting force ku+, in other words, ku if u is positive, and 0 if u is negative. When the cable is loaded, it stretches to a new equilibrium, around which it obeys the linear Hooke's law until deviations from equilibrium become large enough to result in loss of tension when the cable approaches the unloaded state. Using the tools of nonlinear analysis and numerical investigations, we showed that an equation for a nonlinearly supported beam with this type of nonlinearity could explain both large amplitude vertical periodic oscillations and the travelling wave behaviour. With the usual fervor of the newly converted, I suggested that the
SENSITIVITY OF WHITEWATER RAFTING CONSUMERS SURPLUS TO PECUNIARY TRAVEL COST SPECIFICATIONS

Abstract Considerable research has examined how different ways of accounting for onsite and travel time affect surplus estimates from travel cost models. However, little has been done regarding different definitions of out-of-pocket costs. Estimates of per trip consumer surplus are developed for a zonal travel cost model for outfitted rafting on the Chattooga River. Nine price definitions are used for each of three functional forms. Three price definitions are based on mileage rates times round-trip distance, plus outfitter fees. The remaining six definitions are based on reported spending, using three different sets of expenditures and two methods of imputing prices for zero-visit zones.
Histology of normal aortas in non-human primates with emphasis on diffuse intimal thickening (DIT)

Abstract Little information is available on the histology of the normal aorta in non-human primates, despite their extensive use in atherosclerosis research. This paper consists of a detailed histologic description of normal aortas from 28 non-human primates, including 20 species. Medial and adventitial coats were essentially normal in all animals, and the former were composed of lamellar units similar in structure to those described in detail by other investigators. Intimal thickenings were present in 24 of the 28 individuals. These thickenings were similar in morphology to those of diffuse intimal thickening (DIT) in humans and other animals, and were more prevalent in older animals and in larger animals. The thickenings were not more prevalent or more pronounced in any particular region of the aorta, and their distribution did not provide a clue as to their etiology. Findings suggested that the thickenings underwent recognizable stages of growth and maturation, and that growth was accomplished by the addition of smooth muscle cells at the intimomedial junction.
Atomic layer epitaxy of AlAs and AlxGa1xAs for device application

Abstract Atomic layer epitaxy (ALE) of the Al x Ga 1− x As material system for 0 ⩽ x ⩽ 1 has been demonstrated on a converted commercial reactor. A second-generation chamber design allows a broadened ALE region of operation over a wide temperature (550–650 °C) and reactant flow range. ALE of device quality GaAs and AlGaAs has been achieved and ALE growth of AlAs has been obtained for the first time. Background doping levels varied from high resistivity to 10 20 cm −3 and depended strongly on aluminum content x , growth temperature and V:III ratio. Also, uniformity results obtained from photoluminescence emissions of AlGaAs/GaAs quantum wells grown by ALE will be presented and discussed.
Imaging Response and Residual Metastatic Axillary Lymph Node Disease after Neoadjuvant Chemotherapy for Primary Breast Cancer

Background Although surgical management of the breast after neoadjuvant chemotherapy (NAC) may be governed by treatment response, axillary management continues to be determined by stage at presentation. Axillary ultrasound (AUS) with fine-needle aspiration (FNA) is used to detect lymph node (LN) metastases for pre-NAC staging, but imaging assessment of treatment response in the axilla remains undefined. We evaluated post-NAC axillary imaging and surgical pathology to understand how imaging might direct axillary surgery.
T-Cell Recognition of Proteins: Conclusions From the Localization of the Full T-Cell Recognition Profiles of Two Native Proteins

T-Cell Recognition of Proteins: Conclusions From the Localization of the Full T-Cell Recognition Profiles of Two Native Proteins
Measuring private transaction costs of European agri-environmental schemes

Recent changes in European agri-environmental policy allow farmers' transaction costs (TCs), also called private TCs, to be taken into account when calculating compensation payments for agri-environmental schemes (AESs). This gives rise to questions as to the significance of these costs and the methodologies used to measure them. In this paper, private TCs are measured and analysed using two methodologies: (1) through a survey of general perceptions of TCs and (2) through a one-year registration system for monitoring labour hours, operational and administrative costs and differences in revenue between a parcel of land in an AES and a comparable area of land not in a comparable scheme. The results obtained with both methodologies show that private TCs are significant and not to be underestimated. They represent about 15% of the total AES-related costs and about 25% of the compensation payment. The most important cost factor resulting from an AES-uptake is the income foregone which represents more than 50% ...
Thermal stability of supported metal clusters.

Using ab initio many-body potentials and the molecular-dynamics method, we have studied the effect of temperature on the structural integrity of a 55-atom Be cluster in free space as well as when supported on a metal substrate. The melting point of the free cluster is found to be significantly lower than that of the bulk. The melting point of the supported cluster, however, is difficult to interpret due to the strong interaction between the cluster and the substrate. The structure of the cluster undergoes significant rearrangement even at 0 K. Thus the melting point of a supported cluster determined from its change of shape, as is usually done in experimental analysis, can provide misleading information.
The Measles Initiative to control measles in Kenya.

Purpose To describe the epidemiology of measles in Kenya and evaluate the Measles Initiative's (MI's) mass immunization campaign and its impact on measles control in Kenya. Methods This descriptive study focused on evaluating the MI's simultaneous mass campaigns in the provinces of Kenya, the implementation process of the campaign strategy, post-campaign impact data, and pre-campaign measles trends. Secondary data were obtained from the Kenya Ministry of Health and MI documentation involving vaccine coverage, and morbidity and mortality rates. Analysis focused on program achievement with a comparison of immunization coverage results and program goals. Outcomes Campaign goals of vaccination coverage were successfully achieved, and subsequent surveillance data indicate significant decreases in measles morbidity and mortality. Barriers to participation, sociocultural factors, and environmental demographics were identified and addressed. Implications The success of the MI immunization program was the result of the commitment of expert international public health agencies in partnership with the Kenyan government. The strategies used for this successful public health activity can be applied to improve vaccination programs in other countries.
Mesospheric charged dust layer: Implications for neutral chemistry

[1] The presence of a dust layer in the Earth's mesosphere is generally accepted on theoretical grounds (Hunten et al., 1980), but its experimental verification has been difficult and its influence on mesospheric dynamics and chemistry is not yet understood. Four sounding rockets carrying detectors designed to measure nanometer-sized charged dust particles were flown from Poker Flat in March 2002. Ground-based lidars were used to measure neutral sodium and iron densities during the launches in an effort to determine whether dust has an influence on mesospheric chemistry, specifically, as related to atomic Na and Fe. In situ measurements of charged dust and plasma densities were compared with the ground-based lidar data. Strong correlations between the charged dust profile and the neutral Fe profile were observed on all four flights. This finding suggests that dust serves as a reservoir for atomic iron in the mesosphere.
A 50Tbps optically-cabled Infiniband datacenter switch

We present a commercial 50Tbps Infiniband packet switch with 648 ports running 40Gbps per port enabled by 12-channel full-duplex active optical cables with 10Gbps per channel per direction of optical I/O.
A symbolic system for the language-independent classification of welding defects

AbstractThe objective of this paper is to establish a symbolic modelling and coding system for welding defects, which, in conjunction with a severity scaling system, will help alleviate the communication problem within the industry, as well as contributing to better defects identification. This system will facilitate the quick and accurate diagnosis and the correct assessment of welding defects using simple symbols as well as placing them appropriately on the drawings.
Spin‐echo micro‐MRI of trabecular bone using improved 3D fast large‐angle spin‐echo (FLASE)

Fast Large-Angle Spin Echo (FLASE) is a common pulse sequence designed for quantitative imaging of trabecular bone micro-architecture. However, imperfections in the nonselective phase-reversal pulse render it prone to stimulated echo artifacts. The problem is further exacerbated at isotropic resolution. Here, a substantially improved RF-spoiled FLASE sequence (sp-FLASE) is described and its performance illustrated with data at 1.5 and 3T. Additional enhancements include navigator echoes for translational motion sensing applied in a slice parallel to the imaging slab. Whereas recent work suggests the use of fully balanced FLASE (b-FLASE) to be advantageous from a SNR point of view, evidence is provided here that the greater robustness of sp-FLASE may outweigh the benefits of minor SNR gain of b-FLASE for the target application of trabecular bone imaging in the distal extremities, sites of exclusively fatty marrow. Results are supported by a theoretical Bloch equation analysis and the pulse sequence dependence of the effective T2 of triglyceride protons. Lastly, sp-FLASE images are shown to provide detailed and reproducible visual depiction of trabecular networks in three dimensions at both anisotropic (137×137×410 µm3) and isotropic (160×160×160 µm3) resolutions in the human distal tibia in vivo.
Children's Representations of Multiple Family Relationships: Organizational Structure and Development in Early Childhood

The authors examine mutual family influence processes at the level of children's representations of multiple family relationships, as well as the structure of those representations. From a community sample with 3 waves, each spaced 1 year apart, kindergarten-age children (105 boys and 127 girls) completed a story-stem completion task, tapping representations of multiple family relationships. Structural equation modeling with autoregressive controls indicated that representational processes involving different family relationships were interrelated over time, including links between children's representations of marital conflict and reactions to conflict, between representations of security about marital conflict and parent-child relationships, and between representations of security in father-child and mother-child relationships. Mixed support was found for notions of increasing stability in representations during this developmental period. Results are discussed in terms of notions of transactional family dynamics, including family-wide perspectives on mutual influence processes attributable to multiple family relationships.
Breaking down the inner city

Abstract ‘Once cities exist, their renewal is a continuous process’. The quotation is from Lionel Esher (alias Lionel Brett). His book A Broken Wave: the Rebuilding of England 1940–1980 (Penguin, 1983) takes pride of place in this review of a number of recent books on cities.
Monte Carlo simulations of the effect of confinement geometry on the lowering of the glass transition temperature

Abstract An off lattice simulation of the effect of confinement geometry on the glass transition temperature has been conducted using Monte Carlo techniques. The resulting change in volume fraction of occupied space, a measure of density, is monitored to detect the glass transition temperature Tg. Simulations have been conducted on freely jointed polymer chains which have been spatially confined by one dimension (between parallel plates), by two dimensions (in a tube) and by three dimensions (in a sphere). For all three constraint environments the value of Tg decreases as the confining dimension decreases in length. The onset of the decrease occurs first when the confinement is three-dimensional (3D) and the magnitude of the effect is largest for 3D confinement. The effect occurs at values of the confining lengths in 3D confining spheres which are about 33% larger than the value for comparable effects in 2D (tubes) constraining systems. Similarly, the 2D tubes show constraint effects at larger values of the constraint length than 1D plates. The results agree with the trends observed in a recent experimental on the relative effects of constraint geometries.
Analysis of second-order conditional moment closure applied to an autoignitive lifted hydrogen jet flame

The timing and location of autoignition can be highly sensitive to turbulent fluctuations of composition. Second-order Conditional Moment Closure (CMC) provides transport equations for conditional (co)variances in turbulent reacting flows. CMC equations accounting for compressibility and differential diffusion are analyzed using data from direct numerical simulation of an autoignitive lifted turbulent hydrogen jet flame [1]. At the flame base, second-order moments were required to accurately model the conditional reaction rates. However, over 80% of the second-order reaction rate component was obtainable with a small subset (16%) of the species-temperature covariances. The balance of the second-order CMC equation showed that turbulent transport across spatial composition gradients initiates generation of conditional variances.
Problem solving to improve adherence and asthma outcomes in urban adults with moderate or severe asthma: A randomized controlled trial

Background Improving inhaled corticosteroid (ICS) adherence should improve asthma outcomes. Objective In a randomized controlled trial we tested whether an individualized problem-solving (PS) intervention improves ICS adherence and asthma outcomes. Methods Adults with moderate or severe asthma from clinics serving urban neighborhoods were randomized to PS (ie, defining specific barriers to adherence, proposing/weighing solutions, trying the best, assessing, and revising) or standard asthma education (AE) for 3 months and then observed for 3 months. Adherence was monitored electronically. Outcomes included the following: asthma control, FEV 1 , asthma-related quality of life, emergency department (ED) visits, and hospitalizations. In an intention-to-treat-analysis longitudinal models using random effects and regression were used. Results Three hundred thirty-three adults were randomized: 49 ± 14 years of age, 72% female, 68% African American, 7% Latino, mean FEV 1 of 66% ± 19%, and 103 (31%) with hospitalizations and 172 (52%) with ED visits for asthma in the prior year. There was no difference between groups in overall change in any outcome ( P > .20). Mean adherence (61% ± 27%) decreased significantly ( P = .0004) over time by 14% and 10% in the AE and PS groups, respectively. Asthma control improved overall by 15% ( P = .002). In both groups FEV 1 and quality of life improved by 6% ( P = .01) and 18% ( P 1 only occurred during monitoring but not subsequently after randomization. Rates of ED visits and hospitalizations did not significantly decrease over the study period. Conclusion PS was not better than AE in improving adherence or asthma outcomes. However, monitoring ICS use with provision of medications and attention, which was imposed on both groups, was associated with improvement in FEV 1 and asthma control.
Joint transform optical correlator designed and analyzed by use of two- and one-dimensional Hilbert transforms

Novel real-time joint transform, Hilbert transform optical correlators are proposed in which only a half or a quarter of the Fourier plane is written onto an optically addressable spatial light modulator. A point source is used to recover the result for the whole plane. As a result, images with a two- or four-times larger space–bandwidth product can be matched in amplitude and phase. The effect of truncating the transform plane is explained with two- and one-dimensional Hilbert transform analysis. Results of computer simulation are shown.
Automatic Carrier Landing System Utilizing Aircraft Sensors

A new closed-loop control system is developed and evaluated for use in automatic carrier landings. The system is based on a new tracking filter that uses angle of attack and airspeed measurements from the airplane, in addition to the usual ship-based radar measurements. The filter dynamic model is based on actual flight dynamics, using the additional measurements, and thus achieves significant radar noise sensitivity reduction by eliminating the existing dependence on numerical differentiation of the radar output. An additional feedback loop that blends aircraft model estimates with radar measurements is also added to the system. Nonlinear optimization techniques are used to determine a set of optimal filter and control gains for the entire closed-loop system. A detailed digital computer simulation, verified with available flight data, indicates that the use of the flight-dynamics-based tracking filter and the addition of the feedback loop dramatically improves the noise rejection sensitivity in the automatic carrier landing system.
Post-fire uptake of nutrients by diverse ephemeral herbs in chamise chaparral

Diverse populations of ephemeral herbs form the dominant element of community biomass in the first year of growth following a fall burn in chamise chaparral. Ephemeral herbs constituted 337 kg ha-1 of above-ground biomass after the first season of post-fire growth. This was 64% of the total, with the majority of the remaining biomass being in resprouts of Adenostoma fasciculatum. Ephemeral herb biomass following fire in other stands was as high as 1117 kg ha-1. Nutrient contents of ephemeral herbs were 6.68 kg N ha-1, 0.71 kg P ha-1, 10.05 kg K ha-1, 4.75 kg Ca ha-1 and 0.91 kg Mg ha-1. These were 55, 54, 81, 71 and 70% respectively of the above-ground totals. In the second year following fire, the total herb biomass was 40% higher, but the nutrient pool in above-ground biomass of these herbs was only 30–60% of what it had been the first year. Resprouts of A. fasciculatum and short-lived wood shrubs constituted more than 90% of above-ground biomass at this stage of postfire succession.
Drug Preference in Cocaine and Alcohol Dual-Dependent Patients

The present study extended previous work with the multiple-choice procedure (MCP) by examining the monetary value of cocaine and alcohol in dual-dependent patients. Participants made hypothetical choices between pairs of substances and between each substance and a series of monetary values. Results showed that the combination of cocaine and alcohol was preferred over each individual substance. The monetary value at which the substance is no longer chosen was higher for the combination than for one drink or one hit alone. Monetary values showed convergence with dependence-related variables. These findings substantiate the importance of concurrent alcohol and cocaine dependence treatment.
The Ecosystem and the Steady State

A recent survey of microbial ecology (Brock, 1966) has prompted me to consider the ecosystem concept as it relates to the microbial world. Because of the simplicity of strictly microbial ecosystems, the ecosystem concept becomes reduced to its basic essentials, and certain peripheral elements which may confuse a precise analysis are eliminated. The thesis of the present note is that since the ecosystem concept is used mainly as an aid in studying thermodynamic relationships and biogeochemical cycles in nature, an ecosystem should be described as an open system in steady state. As discussed by Eyring et al. (1960), thermodynamics can be applied to open systems only if they are in a steady state. Such a state is a time-independent condition in which production and consumption of each element of the system are exactly balanced, the concentrations of all elements within the system remaining constant, even though there is continual change. A good example of a steady state is an adult human: the body remains more or less constant in the quantity and quality of its elements from puberty to death, even though many cells and tissues of the body are turning over continuously. Food enters, wastes leave, yet everything stays the same. On first thought it might be felt that no ecological system would exhibit steady state conditions. Yet it must be remembered that an important item is the time constant of the system. Although fluctuations in amounts of various elements may occur over a short period of time (as they do in the human body in relation to eating and excretion), if our view of the system covers a long enough period we can ignore these fluctuations and concentrate on
Adaptive continuous-time equalization followed by FDTS/DF sequence detection

Employing an adaptive continuous-time forward equalizer with a Fixed Delay Tree Search with Decision Feedback (FDTS/DF) detector provides several advantages to a magnetic recording system. Although an adaptive continuous-time filter of modest complexity cannot achieve the degree of pulse shape control provided by a long FIR filter, its power consumption may be dramatically lower. An FDTS/DP detector can be easily adapted to widely varying equalized pulses. By combining the two, we can achieve channel performance comparable to that of a system including an FDTS/DF detector and a long FIR equalizer-but with a power dissipation that is potentially much less than conventional sequence detection channels. Simulation results are presented that compare this new approach with a finite length FIR equalizer followed by an FDTS/DP detector. We present and compare several architectures for the adaptive continuous-time equalizer that offer improved convergence when using the least-mean-squares (LMS) adaptation algorithm. >
Increasing the connectivity of the star graphs

The star graph Sn proposed by Akers et al. has many advantages over the n-cube. We show that when a large number of vertices are deleted from Sn the resulting graph can have at most two components, one of which is small. We use this result to solve a successive augmentation problem for Sn. This, in turn, provides extra choices for the topology of large interconnection networks. © 2002 Wiley Periodicals, Inc.
High-gain harmonic-generation free-electron laser.

A high-gain harmonic-generation free-electron laser is demonstrated. Our approach uses a laser-seeded free-electron laser to produce amplified, longitudinally coherent, Fourier transform-limited output at a harmonic of the seed laser. A seed carbon dioxide laser at a wavelength of 10.6 micrometers produced saturated, amplified free-electron laser output at the second-harmonic wavelength, 5.3 micrometers. The experiment verifies the theoretical foundation for the technique and prepares the way for the application of this technique in the vacuum ultraviolet region of the spectrum, with the ultimate goal of extending the approach to provide an intense, highly coherent source of hard x-rays.
Octanoate Attenuates Adipogenesis in 3T3-L1 Preadipocytes

Preadipocytes exposed to octanoate accumulate less lipid than cells exposed to long-chain fatty acids. This effect of octanoate involves significant attenuation of expression of key adipogenic transcription factors, including peroxisome proliferator-activated receptor (PPAR)gamma, steroid regulatory binding element protein (SREBP)-1c and CCAAT element binding protein (C/EBPalpha) at both the mRNA and protein levels. Expression of differentiation markers, including adipocyte fatty acid binding protein (ALBP), glycerol-3-phosphate dehydrogenase (GPDH) and leptin, was also significantly diminished by octanoate. However, octanoate did not prevent the decrease in preadipocyte factor-1 (Pref-1) expression that occurs during adipogenesis, nor did it inhibit the early induction of C/EBPbeta,delta. Treatment with synthetic PPARgamma ligands partially offset the inhibitory effect of octanoate on differentiation. Ectopic expression of PPARgamma2 in 3T3-L1 cells partially restored lipid accretion and GPDH activity in octanoate-treated cells. Adding octanoate together with troglitazone attenuated the effects of troglitazone on adipocyte differentiation in both normal 3T3-L1 cells and engineered 3T3-L1 cells that expressed ectopic PPARgamma2, implying that octanoate might compete against troglitazone for its binding to PPARgamma. These results suggest that octanoate may block adipogenesis at least in part by its influence on the expression/activation of PPARgamma.
Combining dictionary coding and LFSR reseeding for test data compression

In this paper we describe a method to combine dictionary coding and partial LFSR reseeding to improve the ompression efficiency for test data compression. We also present a fast matrix calculation method which significantly reduces the computation time to find a solution for partial LFSR reseeding. Experimental results on ISCAS89 benchmark circuits show that our approach is better than either dictionary coding or LFSR reseeding, and outperforms several test data compression methods proposed recently.
Ensuring Safe Use of Over-the-Counter Cough and Cold Products in Children.

Over-the-counter (OTC) cough and cold prod-ucts for children have been a topic of debate for years. With no clear demonstration of efficacy, a recommendation to use these products for the common cold is not an evidence-based one. However, caregivers and healthcare providers want to intervene to make children more com-fortable while they are ill. Caregivers believe in OTC product efficacy and are likely to begin treat-ment without consulting a pediatrician or other healthcare provider.
Category-Specific Object Recognition and Segmentation Using a Skeletal Shape Model

The success of skeletal model in object recognition from segmented images motivates the development of a skeletal model for top-down object recognition and segmentation. We propose a novel skeleton-based generative shape model which is suitable for efficient search using dynamic programming (DP). We have devised an exclusion principle enabling DP to discover multiple instances of an object category in one pass. Finally, we have improved an oriented chamfer distance for rank-ordering generated hypotheses. Improved or comparable recognition and segmentation results are reported on the ETHZ data set.
Modeling Breaking Ship Waves for Design and Analysis of Naval Vessels Challenge Project C1V

One of the remaining challenges involved in modern Naval ship design and analysis is to account for the effects of breaking waves, spray and air entrainment on various performance measures of a surface ship. The near field flow about a surface ship is characterized by complex physical processes such as: (i) spray sheet and jet formation; (ii) strong free-surface turbulence interactions with (large-amplitude) breaking waves; (iii) air entrainment and bubble generation; and (iv) postbreaking turbulence and dissipation. The challenges associated with this task are twofold. The first is robustly simulating the large-scale problem of the near-field flow of an entire surface ship. The second is the development of physics-based closure models for steep breaking waves in the presence of turbulence. To wit, a two-pronged approach consisting of developing a strong foundation for closure model development and applying cutting-edge parallel computing capabilities has been developed to accurately simulate the free-surface flow around naval combatants which includes these phenomena. Using high-resolution direct numerical simulation of the Navier-Stokes equations using the level set method, we have successfully simulated an ensemble of unsteady breaking waves (currently 36) at Reynolds numbers O(10^3^4). This "breaking-waves database" includes both spilling and plunging breaking waves of varying intensity and is being used as a first step in evaluating closure models for inclusion in existing LES and "off-the-shelf" RANS capabilities. Using NFA (Numerical Flow Analysis), simulations of a gun-ship were performed at a range of speeds. The numerical results show wave overturning at the bow and flow separation at the transom. Air is entrained along the side of the hull and in the rooster-tail region behind the stern. This marks the first time that NFA has been used to simulate an entire ship hull. The numerical simulations were performed on the AHPCRC Cray T3E using 256 processors. Approximately, 90 million grid points were used in the simulation.
Genetic optimization of a fuzzy system for charging batteries

A large variety of nickel-cadmium (Ni-Cd) batteries have been developed to meet a wide range of user needs, ranging from low-current-level uses like emergency power sources for semiconductor memories to very high-power applications such as motor-operated cordless drills. This paper presents a genetic algorithm approach to optimize a fuzzy rule-based system for charging such high-power Ni-Cd batteries. For the optimization of the fuzzy system, a special objective function is developed which is based on the entropy of a fuzzy system. The resulting fuzzy system is able to charge high-power Ni-Cd batteries in about 10 min with a current of 6 A.
Enhanced heat transfer with jet impingement on structured-porous surfaces

A new heat transfer method, which combines the merits of liquid jet impingement heat transfer with metallic porous surfaces, is proposed. The porous surface was made by sintering a single layer or multiple layers of copper wire mesh screen to a plain copper base heat transfer surface. Experiments were conducted with a 2.0-mm diameter circular water jet impinging onto a 6.35-mm diameter circular porous surface. The effects of jet subcooling, flow rates, and porous layer thickness on jet impingement heat transfer performance were explored under atmospheric pressure. The results show that increased subcooling improves heat transfer performance, and that flow rate has an insignificant effect on heat transfer performance when boiling is fully established. The effect of porous layer thickness depends on the specific working condition. With a four layer porous surface, a heat flux of 720 W/cm2 was reached at a wall superheat of 12.4 K.
Situated practices of looking: visual practice in an online world

Graphical virtual worlds are increasingly significant sites of collaborative interaction. Many argue that the simulation of the everyday environment makes them particularly effective for collaboration. Based on a study of visual practice in Second Life, we argue: first, that the practice of looking is more varied than it might at first seem; second, that we need to look beyond the virtual in understanding virtual worlds; and third, that implementations blend interactional practice. We suggest that the value of virtual worlds as sites of collaboration might lie more in their richness and openness to appropriation than in their simulation of everyday interaction.
The Domestic Violence Survivor Assessment: A Tool for Counseling Women in Intimate Partner Violence Relationships

Seeking to end violence and distress in their relationship is the goal of women abused by intimate partners. The theoretical framework guiding development of the domestic violence survivor assessment (DVSA) was Landenburger's theory of entrapment and recovery. Social context and need to balance care for others and herself influence women's decision-making about abuse. The DVSA was developed collaboratively between researchers and counselors to gain a deeper understanding of battered women's cognitive states in order to assist them during counseling to effectively resolve the dilemma of their abusive relationships while experiencing personal growth. Five states are identified which a woman may experience on 11 issues concurrently at the personal, relationship or social context levels. Research to validate the DVSA and suggestions on use with women desiring to preserve their relationship or preserve their self or preserve the resolution of change is described. Using the DVSA for assessment, intervention and measuring intermediate outcomes is delineated.
Free tissue transfer to extend the limits of limb salvage for lower extremity tissue loss

Background The extent of tissue loss amenable to primary healing after revascularization is unknown. Salvage of limbs with large soft-tissue defects with exposed tendon, joint, or bone lies beyond the limits of conventional techniques. We report our results using free tissue transfer as an adjunct to lower extremity vascular reconstruction in patients with complex ischemic or infected wounds. Methods Retrospective chart review of patient and wound characteristics. Results From January 1992 to June 1996, 585 procedures were performed in 544 patients, including 27 free flaps in 26 patients: 17 free flaps combined with distal bypass (7 staged, 10 simultaneous) and 10 isolated free flaps. Flap donor sites included radial forearm (8), latissimus dorsi (7), rectus abdominus (9), and scapula (3). Surgical indications included extensive ischemic/neurotrophic ulcers, and nonhealing vein graft harvest incision or transmetatarsal amputation site. Mean area of tissue loss was 70 cm2, mean ulcer duration was 5 months, and 92% of patients had exposed tendon, joint, or bone. During a mean follow-up of 14 months, 2 patients died of cardiopulmonary disease and 3 flaps failed, resulting in below-knee amputation. Six flaps were revised for graft stenosis (1), venous thrombosis (1), or flap edge necrosis (4). Limb salvage rate was 70% at 24 months by life-table analysis. Functional ambulation was achieved in 21 of 24 (88%) patients, including 7 of 8 with diabetes, end-stage renal disease, and heel ulcers. Conclusion In select ambulatory patients with large soft-tissue defects and exposed deep structures, functional limb salvage is obtainable in more than 80% of patients. For lesions not amenable to vascular reconstruction with conventional methods of wound coverage, free tissue transfer extends the limits of limb salvage and is a viable alternative to amputation.
A Note on Professor Manne's “Dominance” Theorem

Professor Manne's paper recently appearing in this Journal Manne, A. S. 1958. Programming of economic lot sizes. Management Sci.4 2, January. is an ingenious application of linear programming technique to what may have hitherto been regarded as an intractable non linear situation. The excellences of the paper are, however, marred by a gap in the proof of the “Dominance” theorem. It is the aim of this communication to point out that, although the constructive proof offered by Manne is vulnerable to counter-example, an alternative, fairly simple, proof can be given. The theorem being true, the important results of the paper are not weakend.
Perpetrators as victims: Understanding violence by female street-walking prostitutes

Little is known about the perpetration of violence by women who engage in street prostitution. While some researchers have examined the incidence of abuse among this population, the association between receipt of abuse and violence and later perpetration of violence is unclear. This study presents data from a recent evaluation of a case management program for street-walking prostitutes. A description of the program clients is provided, and factors that are associated with assaultive behavior against clients are examined. Bivariate analyses revealed statistically significant differences between assaultive and nonassaultive women with regard to history of psychiatric hospitalization, history of sexual abuse, history of physical abuse, history of emotional abuse, and whether they had been assaulted on the streets. However, logistic regression on variables related to abuse and violence indicates that controlling for other variables, the only statistically significant predictor of assaultive behavior was history of physical abuse. These results indicate the need for further research on this population as well as access to treatment for these women to address their own abuse and victimization. Language: en
Experimental determination of Fe isotope fractionation between aqueous Fe(II), siderite and “green rust” in abiotic systems

Abstract Iron isotope fractionation between aqueous iron and siderite has been measured using abiotic synthesis experiments at ∼20 °C. Applying a Rayleigh distillation model to three experiments in which siderite (FeCO3) was continuously precipitated from solutions over the course of tens of hours, the derived fractionation factor is 103lnαFe(II)–Siderite=+0.48±0.22‰ (2σ). This experimentally determined fractionation factor is significantly smaller (by ∼1.5‰) than that calculated from vibrational frequencies and Mossbauer shifts [Geochim. Cosmochim. Acta 64 (2000) 849–865; Geochim. Cosmochim. Acta 65 (2001) 2487–2497], and lies on the high end of that inferred from natural mineral assemblages, where the Fe(II)aq–siderite fractionation factor was inferred to lie between −1.7‰ and +0.3‰ [Contrib. Mineral. Petrol. 144 (2003) 523–547]. The measured Fe(II)aq–siderite fractionation from this study suggests that siderite from Archean and Proterozoic rocks, which have moderately negative δ56Fe values (−1.5‰ to −0.5‰), may reflect precipitation from Fe(II)aq whose origin was hydrothermal. In contrast, natural siderites that have higher δ56Fe values apparently require non-hydrothermal sources of Fe and/or different pathways of formation, or may reflect the effects of cation substitution on the Fe(II)aq–carbonate fractionation factor.
Psychometric Issues in the Assessment of Impairment

One of the greatest contributions psychologists have made to society is the development of methods for quantifying the various constructs used in the field. In fact, without methods of quantification, little research could be conducted, and practitioners would be limited to subjective interpretations of informal data they obtain. The development of tools used to assess psychological constructs has greatly improved the reliability and validity of the field, perhaps the most obvious ones being personality and intelligence tests. It is important to recognize that the study of any psychological construct is very dependent on the quality and content of the tools used. And, the methods included in scientific research directly influence the results of any study and consequently what is learned about the topic. Importantly, we must recognize that what we learn from a test is completely determined by the content of the instruments and the specific information they provide. The quality of these tools, therefore, is directly proportional to the quality of the information obtained and based on the way in which test authors conceptualize and measure their constructs. The better the tool, the more reliable and valid our findings, and as validity increases, so does the quality of the information that is obtained and, ultimately, the better the services provided. In this chapter, the tools used for assessment of impairment are examined.
Argument Integration and Attitude Change: Suppression Effects in the Integration of One-Sided Arguments that Vary in Persuasiveness:

Petty and Cacioppo's elaboration likelihood model of persuasion and Chaiken, Liberman, and Eagly `s heuristic-systematic model suggest that for highly involved message recipients, adding weaker arguments to strong arguments could suppress or dilute the overall persuasiveness of a message. The few previous studies addressing this prediction, however, have provided conflicting evidence. In the present study, involvement level, number of weak arguments, and number of strong arguments were varied factorially in a message advocating the institution of senior comprehensive exams. Results provided clear support for the predicted weak-argument suppression of attitude change. Analyses of thought-listing data supported the notion that suppression results from the integration of favorable and unfavorable cognitive responses to the communication. Further research questions regarding the processes by which mixed-quality messages exert theirpersuasive impact are discussed.
CT Radiation Dose and Image Quality

Image quality is proportional to radiation dose. Improvements in image quality come at a cost of increased radiation dose. CT scanners are more robust today than even 5 years ago. X-ray tubes are capable of producing high levels of almost continuous radiation for rapid CT volume acquisitions and angiographic studies. All parameters of modern CT scanners provide rapid subsecond, large-volume CT acquisitions. How high we go needs to be tempered by how high we should go regarding radiation dose from CT examinations. Radiologists, referring physicians, medical physicists, CT technologists, CT equipment manufacturers, and regulators need to evaluate the appropriateness of radiation dose for different CT studies.
Offering engaging educational programs for K–12 students (ages 5–18): Examples, perspectives, and recommendations

Educational outreach efforts for K–12 students, ages 5–18, are becoming increasingly visible, active, and pervasive in the materials science community as a result of funding agency requirements in the United States and gradual institutional attitudinal shifts toward placing a higher emphasis on engaging non-technical audiences. Many scientists recognize it as both an obligation and a pleasure to share their research with young audiences. However, in addition to enthusiasm and funding agency mandates, equally essential to successful educational outreach projects are effective, engaging educational materials and programs. Hands-on demonstrations, classroom lesson plans, summer research internships, and education-oriented laboratory experiments are just a few examples of the wide variety of possibilities from which materials scientist educators can currently choose. This article addresses the process of developing educational outreach activities and programs, including setting goals, establishing partnerships, and planning for and implementing outreach activities for students. Examples from the materials science outreach community are integrated to illustrate implementations of these ideas and to offer ideas for collaborations and future projects.
Atypical cystic meningioma of the trigeminal nerve in a pediatric patient.

SUMMARY: We report an unusual case of atypical cystic meningioma of the trigeminal nerve proved by histology in a 15-year-old white girl. A review of the literature showed that this is only the second reported case of a meningioma of the trigeminal nerve without dural attachment and the first occurrence in a pediatric patient.
The Case for Lying, Cheating, and Stealing-Personal Development as Ethical Guidance for Managers

The interpretivist perspective is rapidly growing in acceptance and influence in the feld of organization and management. This perspective has important implications for the field of administrative...
Prion Protein-Hemin Interaction Upregulates Hemoglobin Synthesis: Implications for Cerebral Hemorrhage and Sporadic Creutzfeldt-Jakob Disease

Hemin is known to induce endocytosis of prion-protein (PrP(C)) from the neuronal plasma membrane, potentially limiting propagation of the disease causing PrP-scrapie (PrP(Sc)) isoform. Hemin is therefore an attractive disease-modifying option for sporadic Creutzfeldt-Jakob disease (sCJD), a human prion disorder with no effective treatment. The hemin-PrP(C) interaction is also of interest in cerebral-hemorrhage (CH), a condition where potentially toxic hemin molecules come in contact with neuronal PrP(C). Interestingly, PrP(C) is upregulated in penumbric neurons surrounding CH and is known to confer neuroprotection in a dose-dependent manner. The underlying mechanism, however, is not clear. Here, we report that hemin binds PrP(C) on diverse cell lines, resulting in its aggregation or degradation in a cell-type specific manner. Surprisingly, the hemin-PrP(C) interaction upregulates Hb synthesis in hematopoietic cells, a response reversed by deleting the hemin-binding octa-peptide repeat region of PrP(C). A similar response is noted in brain organotypic cultures where exposure to hemin induces significantly more α-globin in wild-type (PrP(+/+)) relative to PrP-knock-out (PrP(-/-)) samples. Furthermore, red blood cells and brain tissue from PrP(-/-) mice show significantly less α-globin relative to PrP(+/+) controls, indicating a positive effect of PrP(C) on Hb synthesis under physiological conditions as well. Surprisingly, levels of α-globin are significantly higher in sCJD brain tissue relative to controls, suggesting compensatory upregulation of Hb synthesis by surviving neurons or misregulation in diseased brains. These observations reveal a unique function of PrP(C) that is likely to impact the therapeutic management of CH and sCJD.
Optimization of reverse saturable absorber limiters: material requirements and design considerations

We present numerical beam-propagation simulations of optimized reverse-saturable absorption (RSA) based optical limiters where the depth of focus of the input beam is much smaller than the thickness of the nonlinear material. The optimization is achieved by allowing the molecular concentration to vary along the propagation path, allowing the entire length of the limiter to reach the maximum possible nonlinear absorption before eventual damage to the limiter. We review in detail the analytic model originally derived by Miles [1] to determine the design and performance of such limiters. This model requires the usual 5-level model used in the numerical solution to be approximated by a quasi-three-level system. We show that this effective 3-level excited-state cross section is both pulsewidth and fluence dependent. The numerical propagation output shows that there is considerable diffractive beam distortion, which cannot be accounted for in the analytic model. The end result is that while there is qualitative agreement with numerical results, the magnitude of the limited output can be an order-of-magnitude underestimated. We determine that the fluence level at all parts of the limiter must be at least ten times the saturation fluence to efficiently utilize the nonlinear absorption. We further describe how the optimized distribution of molecular density is the limit of the multi-element tandem limiter for an infinite number of elements. By carefully accounting for saturation over the entire length of each individual element, we show how a multi-element limiter may be designed to closely approach the performance of the optimized distribution for as few as four elements. With current materials technology the damage threshold of solid hosts needed to vary the molecular density is much lower than that of glass cuvettes used for liquid based limiters. Therefore, a multi-element liquid based tandem limiter can be used in full saturation so that better limiter performance should be obtained. Ultimately, however, the operation of all RSA-based limiters involves a strict trade-off between performance and linear transmittance.