cssi/SciSciGPT-SciSciNet huggingface dataset:
AN APPLICATION OF COMMERCIAL PANEL DATA FOR PUBLIC POLICY RESEARCH: ESTIMATES OF TIP EARNINGS

Unique panel data provided by NPD Research, Inc., were used to investigate the magnitude and interactive effects upon tipping aggregates and levels. The analysis revealed that tips by American households aggregate to $6.2, $6.3, and $6.7 billion annually in restaurants and other eating places in 1982, 1983, and 1984 respectively. The information was collected by means of diaries kept by the tippers themselves, which was regarded as a more accurate source than inquiries of either the tip recipients or their employers. The paper covers the relationship between the characteristics of the tippers and of the tipping occasions and the propensity and magnitude of tipping. One finding of the regression analysis is that there are sizable differences in tip rates across tipping type restaur­ ant categories when the combined effects of geographic region, metropolitan size, and restaurant options such as acceptance of credit cards and reservations and service of alcoholic beverages are considered.
W. H. R. Rivers Prize Essay (1992). Stories of Pain and the Problem of AIDS Prevention: Injection Drug Withdrawal and Its Effect on Risk Behavior

This study shows that drug withdrawal can be interpreted as a chronic pain condition that bridges the physical and emotional experiences of pain, especially regarding feelings of rejection, shame, inadequacy, and isolation. The experience of withdrawal among drug users, both in treatment and actively using drugs, in a predominantly working-class, industrial Massachusetts city of 185,000 was studied through questionnaires, interviews, and ethnographic observation. The results suggest that the physical effects of drug use need to be explored as a symptom of a more extensive chronic condition in which pain is both the reason for and the consequence of drug addiction. This pain condition makes avoiding needle sharing and cleaning injection equipment with bleach difficult for many drug users because tolerance of withdrawal symptoms requires tolerating not only physical symptoms but also a more complex constellation of symptoms. This research suggests that AIDS education may need to address the notion of drug withdrawal and its effect on risk-taking behavior.
Effects of fatty acids on gap junctional communication: Possible role in tumor promotion by dietary fat

Dietary lipids, in particular unsaturated fat, promote the development of many experimental tumors. However, no mechanisms to fully explain these effects have been elucidated. Recent reports, which we summarize here, suggest a role for gap junction-mediated intercellular communication in the process of tumor promotion. We also review tumor-promoting effects of dietary fat on experimental, particularly mammary, carcinogenesis. Our main focus is to review recent data examining the inhibitory effects of unsaturated fatty acids on metabolic cooperation in Chinese hamster V79 cells. These data suggest that inhibition of junctional communication may be involved mechanistically in the promotion of tumors by high levels of dietary unsaturated fat. Finally, potential mechanisms by which unsaturated fatty acids inhibit metabolic cooperation are examined.
Enhanced charge transfer in dielectric fluids containing conducting particles

The motion of conducting particles in electrically stressed dielectric fluids has been examined with the intention of explaining enhanced charge transfer between electrodes in the fluid-particle system. The motion of the particles is due to induction charging and the consequent forces exerted on the particles by an electric field. It is shown that the usual assumptions relating to the velocity of such particles are not substantiated by experiments. The dependence of the enhanced charge transfer on the applied field is derived for one particular case. For this case the study of particle motion shows that particles of different sizes move with a charge equivalent to a maximum voltage on the particle of the order of 16 v. If it is assumed that the particles initially become charged when in contact with one of the electrodes, and on leaving the electrodes are shielded so that the effective charge is reduced, it is possible to show that the current is proportional to the square of the applied voltage, which is in agreement with experimental results.
Design of launch systems using continuous improvement process

The purpose of this paper is to identify a systematic process for improving ground operations for future launch systems. This approach is based on the Total Quality Management (TQM) continuous improvement process. While the continuous improvement process is normally identified with making incremental changes to an existing system, it can be used on new systems if they use past experience as a knowledge base. In the case of the Reusable Launch Vehicle (RLV), the Space Shuttle operations provide many lessons. The TQM methodology used for this paper will be borrowed from the United States Air Force 'Quality Air Force' Program. There is a general overview of the continuous improvement process, with concentration on the formulation phase. During this phase critical analyses are conducted to determine the strategy and goals for the remaining development process. These analyses include analyzing the mission from the customers point of view, developing an operations concept for the future, assessing current capabilities and determining the gap to be closed between current capabilities and future needs and requirements. A brief analyses of the RLV, relative to the Space Shuttle, will be used to illustrate the concept. Using the continuous improvement design concept has many advantages. These include a customer oriented process which will develop a more marketable product and a better integration of operations and systems during the design phase. But, the use of TQM techniques will require changes, including more discipline in the design process and more emphasis on data gathering for operational systems. The benefits will far outweigh the additional effort.
Effect of learning on hemispheric dominance and free recall in a single subject.

-This experiment was designed to investigate the effect of learning on the free recall of letters presented tachistoscopically either to the left visual field, the right visual field, or identically and simultaneously to both visual fields. A modified Shine-Bower analysis of variance was used to analyze S's performance. The results indicate that initially, in accord with previous research, the right visual field is superior to the left visual field in performance, but that chis superioricy tends to reduce across trials and practically disappears in the later trials. Also, the right visual fie:d condition is not appreciably better in performance than the condidon with both visual fields.
The separate and combined effects of GSR biofeedback and delayed auditory feedback on stuttering: A preliminary study

Abstract The separate and combined effects of galvanic skin response biofeedback low wave amplitude self regulation (GSR LW) and amplified delayed auditory feedback (DAF) upon stuttering dysfluency are examined. Two college age male stutterers who were seen on an intensive longitudinal basis were the subjects in this study. Results suggest that GSR LW, when it is accomplished, functions to moderately but significantly reduce stuttering dysfluency compared to no GSR biofeedback. This effect does not noticeably dissipate over time. There occurred a marked and sustained reduction in stuttering dysfluency under DAF compared to no DAF conditions. Without separating accomplished and not accomplished GSR LW, there occurred slightly but not statistically significantly fewer blocks under the combined DAF-GSR LW condition than under DAF alone. Nevertheless, it does seem likely, considering these findings overall, that when GSR LW is accomplished, the fluency facilitating effect of its simultaneous combination with DAF is additive i.e., greater than either alone. Possible theoretical and therapeutic implications are discussed.
Optical Image Subtraction Techniques, 1975 - 1985

Real- and nonreal-time optical image subtraction (OIS) techniques are reviewed. Real-time OIS techniques include source encoding, polarization modulation, pseudocolor image difference detection, the holographic shear lens technique, and nonlinear optics. Included in the nonreal-time category are speckle diffuser encoding, speckle-pattern encoding, halftone screen encoding, and polarization-shifted encoding. It is concluded that the most useful techniques are the real-time operations. It is noted that some nonreal-time optical techniques can be applied directly while others may be converted into real-time ones through the use of advance real-time spatial light modulators or electrooptic devices.
Response factorization of simply connected Ising lattices with application to bethe lattice spin glasses

The thermodynamics of a classical lattice gas in Ising form, with arbitrary interaction, is set up in entropy format, with multipoint magnetizations as control parameters. It is specialized to the case of one- and two-point interactions on a simply connected lattice; both entropy and profile equations are written down explicitly. Linear response functions are expressed in Wertheim-Baxter factorization and used to derive the Jacobian of the transformation from couplings to magnetizations. An arbitrary spin-glass coupling distribution is transformed to the corresponding magnetization distribution, whose effect on thermodynamic properties is assessed. A Gaussian coupling-fluctuation expansion diverges at sufficiently large fluctuation amplitude, suggesting the possibility of a phase transition.
Differential Determinants of Young Adult Substance Use and High‐Risk Sexual Behavior1

This investigation evaluated how personality traits, self-efficacy, and outcome expectancies differentially relate to young adult substance use and high-risk sex. Experiments I (N= 481) and 2 (N= 73) report the development of a new questionnaire to assess self-efficacy for substance use and sexual behavior. Experiment 3 (N= 375) tested self-efficacy, outcome expectancies, and trait measures of social conformity and sensation seeking as correlates of substance use and high-risk sex. Using structural equation modeling, cross-sectional analyses revealed that positive outcome expectancies had the largest association with substance use, whereas self-efficacy had the largest association with sexual behavior. Further, personality traits were related to substance use and sexual behavior indirectly through outcome expectancies, with social conformity also having a direct effect on behavior. When examined longitudinally, past alcohol and drug use served as the final pathway by which expectancies and personality impacted substance use, whereas past behavior, self-efficacy, and social conformity all contributed to high-risk sex. Results support the utility of different models for explaining, and possibly preventing, young adult substance use and high-risk sex.
Evaluation of the laminar diffusion flamelet model in the calculation of an axisymmetric coflow laminar ethylene–air diffusion flame

Abstract A numerical study of an axisymmetric coflow laminar ethylene–air diffusion flame at atmospheric pressure was conducted using detailed chemistry and complex thermal and transport properties and two different methodologies: (1) the direct simulation method of solving the two-dimensional axisymmetric elliptic governing equations, and (2) the steady-state stretched diffusion flamelet model. Soot formation and radiative heat transfer were not taken into account in these calculations, both for simplicity and to avoid the complications associated with the issues of how to incorporate these chemical and physical processes into the flamelet model. The same reaction mechanism and thermal and transport properties were used in the 2D direct simulation and the generation of the flamelet library. The flamelet library was generated from the solutions of counterflow ethylene–air diffusion flames at a series of stretch rates. Results of the 2D direct simulation and the flamelet model are compared in physical space. Although the overall results of the flamelet model are qualitatively similar to those of the direct simulation, significant differences exist between the results of the two methods even for temperature and major species. The direct simulation method predicts that the peak concentrations of CO2 and H2O occur in different regions in the flame, while the flamelet model results show that the peak concentrations of CO2 and H2O occur in the same region. The flamelet model predicts an overly rapid approach to the equilibrium structure in the downstream region, leading to significantly higher flame temperatures. The main reason for the failure of the flamelet model in the downstream region is due to the neglect of the effects of multidimensional convection and diffusion and the fundamental difference in the chemical structure between a coflow diffusion flame and a counterflow diffusion flame. The findings of this paper are highly relevant to understanding the flamelet model results in the calculations of multidimensional turbulent diffusion flames.
The Cramer-Rao Bound for Training Sequence Design for Burst-Mode CPM

In this paper, we study the Cramer-Rao bound (CRB) for continuous phase modulation (CPM) signals where frequency offset, carrier phase, and symbol timing are jointly estimated when transmitted over an additive white Gaussian noise (AWGN) channel. We consider a data-aided (DA) estimation scenario in which the estimator takes advantage of a known training sequence at the start of each burst. Thus, we first derive the joint CRBs as functions of a known training sequence and CPM parameters. By analyzing the CRB expressions, we propose the optimum training sequence for which the CRB is minimized. We show that the same training sequence is optimum for all three estimation parameters. Additionally, we compare the performance of the optimum training sequence with a random one by providing a closed-form expression for the unconditional CRB (UCRB) for symbol timing estimation of CPM signals. Comparing the UCRB and the CRB for the optimum training sequence reveals that a DA estimator with the optimum training sequence leads to significant gains in terms of the mean-square error of the estimation parameter when the underlying CPM scheme is non-binary and/or partial response.
Parental history of hypertension and cardiovascular responses to behavioral stress in young black women

Beta-adrenergic sympathetic nervous system (SNS) hyperresponsivity to behavioral stress may play a role in the onset of sustained high blood pressure--particularly in persons with a parental history of hypertension. Although hypertension is extremely prevalent among blacks, the association between parental history of hypertension and cardiovascular hyperresponsivity has not been explored in this group. The present study examined the influence of parental history of hypertension on cardiovascular stress reactivity in a group of young black females. Contrary to previous findings with whites, black subjects with a parental history of hypertension exhibited significantly smaller systolic blood pressure and forearm blood flow increases, and moderately smaller diastolic blood pressure increases to the task. Parental history subjects also exhibited slower heart rates throughout each experimental condition. The results suggest that blacks at risk from hypertension may not exhibit the beta-adrenergic hyperresponsivity to behavioral stress observed in whites. These results may suggest that beta-adrenergically mediated hyperresponsivity may be less involved in the development of hypertension among blacks.
Temperature and field interrelation study of low-k TDDB for Cu interconnects with and without liner - New insights to the roles of Cu for a competing breakdown process

Low-k time dependent dielectric breakdown (TDDB) is commonly considered an important reliability issue. It has been proposed that there is an interrelation of field and temperature dependence between TDDB thermal activation energies and field acceleration parameters, which could provide a more comprehensive picture to understand low-k TDDB breakdown mechanism. In this study, an extensive investigation of low-k TDDB degradation at 32nm over a wide range of fields and temperatures was conducted for Cu interconnects with and without regular TaN/Ta liner. New interrelations of field and temperature dependence between TDDB thermal activation energies and field acceleration parameters for Cu samples with and without liner were experimentally identified, which provide a new insight to roles of Cu in low-k TDDB breakdown model.
Malpractice Reforms: Are they Fair?

In the debate over medical malpractice reform, the dimension of fairness often is invoked but is poorly understood. This article describes the factors that promote fairness in public policy and then examines whether proposed or enacted tort reforms would be fair. It finds that many of the reforms that are being promoted by perinatologists would be unfair; however, some reforms, including one broad-ranging proposal that was put forward by the Institute of Medicine, could satisfy fairness criteria depending on how they were implemented.
Abstract 3913: Estrogen receptor beta and estrogen receptor beta 5 in triple negative breast cancer cells: IGF-II role in regulation of estrogen receptor beta 5

African American (AA) women with breast cancer are more likely to be diagnosed at a more advanced stage of the disease, have a higher recurrence rate and a poorer prognosis than Caucasian (CA) women. They also are more often diagnosed with high-grade breast tumors at an earlier age (pre-menopausal), most of which are negative for the estrogen and progesterone receptors (ER-, PR-). These factors result in a higher mortality rate among AA breast cancer patients. Our lab has demonstrated that AA women have increased levels of IGF-II coupled with lower levels of the IGF-II receptor needed to degrade IGF-II, thus leading to higher IGF-Ii signaling in contrast to CA women. AA women also have a higher expression of the insulin receptor A versus insulin receptor B when compared to CA women, which increases proliferation and decreases metabolic effects (Singh et. al 2011). We have also shown that IGF-II activates the estrogen receptor alpha (ER-α) and estrogen receptor beta (ER-α) in the absence of the estrogen ligand (Richardson et. Al 2011). When co-expressed, ER-α counteracts the proliferative function of ER-α, however the role of ER-α in breast cancer is different in ER-α negative compared to ER-α positive tumors. Furthermore, there are 5 different isoforms of ER-α, of which ER-Δ5 is the most abundantly expressed form in AA women. Since IGF-II activates ER-α and ER-Δ5 is associated with increased mortality and decreased time recurrence, we have designed a study to determine if IGF-II regulates ER-Δ5. We hypothesize that in the absence of ER-α, ER-α may activate the ER-α signaling pathway, and that the elevated expression of ER-Δ5 and its heterodimerization with of ER-α1 contributes to the overall survival disparity. To test this hypothesis we characterized the levels of phophorylated ER-α (pER-α) and compared them to IGF-II levels in triple negative breast cancer cells and normal triple negative epithelial cells. IGF-II levels were analyzed using western blotting for protein, and RT-PCR for mRNA. AA women have a higher expression of IGF-II in both malignant and normal cells, and comparably higher levels of expression of the active form of ER-α when compared to CA breast cancer cell lines. IGF-II stimulation promoted the translocation of ER-Δ5 to different cellular compartments. We propose that ER-Δ5 impairs the inhibitory effects of ER-α and thus may contribute to the survival disparity among AA breast cancer patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3913. doi:1538-7445.AM2012-3913
Magnesium: Physiology, clinical disorders, and therapy

Magnesium imbalance is clinically significant. It is common, treatable, and frequently overlooked. We review the literature describing magnesium deficit and excess syndromes and formulate specific treatment protocols.
Foreign Aid and Voting in the UN General Assembly, 1967—1976

This paper examines the relationship between foreign (economic) aid and the General Assembly votes for the period 1967-76. The countries included in this study are the United States, the Soviet Union, and those of their aid recipients which are considered less developed. Two related hypotheses, one on the use of aid as an inducement and the other as a reward or a punishment, are tested. The methods used are Index of Agreement, devised by Arend Lijphart, and Pearson's r. The findings indicate that the American aid is more effective as an inducement and the Soviet aid is more effective as a reward or a punishment. The former has a closer association with the General Assembly votes from 1967-73 than in later years. Economic aid is increasingly used by the United States more to serve its security interests in the Middle East than for any other purpose, and it is possible that not so much of a return for the American aid is expected in the UN as was the case earlier.
Studies in hypertension: Implications for clinical medicine

Population studies that demonstrated risk from elevation of blood pressure were a necessary foundation for a sound clinical approach to hypertension. Clinical trials then demonstrated that lowering pressure with drug therapy dramatically reduced risk of cardiovascular catastrophes, including death. The U.S. Veterans Administration (VA) study proved the need to treat moderate and severe hypertension, but left unproven the benefit for so-called mild hypertension (diastolic blood pressure 90–104 mm Hg). The Hypertension Detection and Follow-up Program (HDFP) investigated applicability of VA findings to the “average” hypertensive, particularly to the majority in the range 90–104 mm Hg. Two randomly constituted groups, Stepped Care (SC) and Referred Care (RC), included 10,940 hypertensives, age 30–69, identified in population-based screening in 14 communities, and followed for 5 years. Almost 34 (71%) were so-called mild hypertensives. SC patients were treated vigorously in special clinical centers to lower pressure to a diastolic goal no higher than 80–90 mm Hg (depending on entry level), starting with low dose diuretics and adding medication stepwise as needed, until the goal was reached. RC patients were treated by usual sources of medical care. A larger proportion of SC than RC patients were on therapy and at the goal each year of the study. The fifth year diastolic average was 84 mm Hg in SC and 89 mm Hg in RC. The 5-year all causes mortality rate was 17% lower in SC than RC. In the mild hypertension stratum, this difference was 20%. Clinical implications from the HDFP trial include demonstration of: the validity of the VA findings on the benefit of treating moderate and severe hypertension; the benefit of treatment also for those with sustained average diastolic pressures 90–104 mm Hg; the utility of lowering pressure before target organ damage; the utility of stepwise drug treatment to a normotensive goal; the ability to achieve long-term patient adherence; the contribution of nonphysician personnel in helping achieve these aims. The possible role of non-pharmacologic measures was not tested in these trials and remains an important question in determining best methods for control of hypertension.
Surface photovoltage due to photo-thermo-ionization of surface states: GaAs

Surface photovoltage spectroscopy was employed for studying the mechanism of subbandgap photoionization transitions from surface states in GaAs surfaces. It was found that the photoionization cross-section exhibits a maximum for a photon energy of about 0.9 eV. This finding indicates a photo-thermal mechanism of photovoltage, i.e., photo-induced transitions between surface state levels and the subsequent thermal ejection of electrons from the upper level into the conduction band.
From the Editor in Chief: Interface Pains

Maximizing the amount of information a system conveys to a user isnt a good idea. Rather, designers should keep in mind what the user is trying to accomplish and figure out how to minimize the effort (physical and intellectual) that the user has to expend to get that task done. But given that acting in opposition to good interface design is the reality of engineering projects, a discussion of the design of usable systems seems appropriate.
Catalytic Implications for Keggin and Dawson Ions: A Theoretical Study of Stability Factors of Heteropolyoxoanions

Hetreropolyoxoanions(HPAs) have received wide spread attention due to their unique oxidation-reduction properties in catalysis. Two main structural motifs groups of HPAs have been described by Keggin and Dawson. The first is composed of twelve distorted, octahedrallycoordinated metal atoms forming trimeric and tetrameric subunits connected such that a closed shell results. The second is formed by fusing two Keggin units. The most common Keggin ions(XM12O40n−,) with Td symmetry and the Dawson ions(X2M18O62n−) with D3h symmetry are the α-isomers; while the β-isomers are generated by rotating one trimer 60° along its C3 axis, thus producing the Cs, symmetry for β-Keggin ions and D34 symmetry for β-Dawson ions. Here, M is the framework metal atom, usually Mo, W, and X is the central heteroatom which can be the metal or nonmetal. From our previous studies, the instability of β-isomers caused by the “rotated” trimer can not be compensated by other coordination effects within the cluster and therefore defect states are retained between the HOMO-LUMO gap relative to the α-isomer. This enhances catalytic properties and causes thermal/photo lability. The catalytic function of a-Keggin ions are well studied; however, related research reports about Dawson ions are rare. The α-Dawson ion possesses stronger oxidizing ability and higher activities in oxidative dehydrogenation and oxygen addition reactions than the α-Keggin ions; the β-isomers have a greater tendency to be reduced than the α-isomers. Most of the characterization methods applied have not yielded the electronic or the structural requisites for the catalytic properties of the HPAs. In this work, the theoretical analysis is done through the application of crystal/tight binding theory coupled with the extended HMckel methodology. The stability trends and the redox behaviors provided by this work reliably trace the experimental data. In addition, the intrinsic instability and the redox effects in the β-isomers with respect to the α-isomers is assessed and a rationale for the observed catalytic and electronic develpoment of structrual function is also offered.
Marital Decision Making: Congruence of Spouses' Responses*

The relationship between spouse's perceptions concerning who makes decisions and the importance of decisions was investigated through interviews with 140 couples. A positive relationship was found between the husbands' decision-making scores and the importance of decisions. In addition, the paper emphasizes the need to (1) analyze decision-making and importance of decisions within couples rather than among all husbands and all wives separately and (2) collect data from both spouses.
GUS expression driven by constitutive and phloem-specific promoters in citrus hybrid US-802

Transgenic solutions are being widely explored to develop huanglongbing (HLB) resistance in citrus. A critical component of a transgenic construct is the promoter, which determines tissue specificity and level of target gene expression. This study compares the characteristics of five promoters regulating the beta-glucuronidase (GUS) reporter gene in the trifoliate hybrid rootstock US-802. Two of the selected promoters direct high levels of constitutive transgene expression in other dicotyledonous plants: 2X35S, the tandem-repeat promoter of the cauliflower mosaic virus 35S gene and bul409S, a truncation of the potato polyubiquitin promoter. Because Candidatus Liberibacter, the Gram-negative bacterium associated with HLB, infects only the phloem tissue, it may be advantageous to limit transgene expression to the vascular tissue and reduce expression in the fruit. Thus, we also tested three promoters that demonstrate phloem specificity when transformed and expressed in other plants: WDV, from wheat dwarf geminivirus; AtSUC2, the sucrose-H+ symporter gene promoter from Arabidopsis; and CsSUS, the sucrose synthase promoter from citrus. Histochemical staining for GUS activity was observed throughout leaf and stem tissues for the constitutive promoters, while the three phloem-specific promoters largely showed the expected tissue-specific staining. Expression of GUS in some individual transformants with promoters CsSUS and WDV appeared leaky, with some laminar tissue staining. Relative quantification of qRT-PCR data revealed a wide range of mRNA abundance from transgenics with each of the five promoters. Fluorometry also revealed that GUS activity differed depending on the promoter used, but mRNA levels and enzyme activity were not highly correlated.
The relationship of mother–child interaction and the child's development of symbolic play

Nous avons enquete sur la mesure dans laquelle la relation interactive mere-enfant soit promeut soit limite l'abilite qu'a l'enfant de voir les options ou les choix dans son milieu. Nous avions predit que la qualite de l'interaction essentiellement offerte par la mere serait liee au developpement cognitif de l'enfant, tel que le reflete son niveau de jeu symbolique. Le niveau et la frequence du jeu symbolique et nonsymbolique de 30 enfants, âges de 12 a 47 mois, ont ete codes et les comportements d'encouragement aux options et de limitation des options des meres ont ete identifies. Les enfants, entre ces âges, dont les meres creaient un contexte social de promotion d'option se sont livres a des jeux plus symboliques. Cependant, nous n'avons pas trouve que le jeu nonsymbolique soit influence de maniere significative par le style interactif de la mere. Le jeu symbolique de l'enfant marque une reussite dynamique du developpement pour l'enfant, et semble etre lie au contexte social cree par le style interactif de la mere.
Experience-Dependent Plasticity in S1 Caused by Noncoincident Inputs

Prior work has shown that coincident inputs became corepresented in somatic sensory cortex. In this study, the hypothesis that the corepresentation of digits required synchronous inputs was tested,...
The Microsoft challenge

In 1996, the Microsoft Corporation introduced a new giving programme to members of the University of Washington. Rather than simply donating in cash or kind, it offered to match any funds donated by faculty members to graduate students. The response to the programme was overwhelming initially. However, the organisers changed the rules of the challenge and over time, donations went down. Finally, the company indicated that it wanted to wind down the programme. This case offers unique data and perspective on how to use a challenge as part of a fundraising strategy. Copyright © 2001 Henry Stewart Publications
Noninvasive in vivo optical assessment of blood brain barrier permeability and brain tissue drug deposition in rabbits

Osmotic disruption of the blood brain barrier (BBB) by intraarterial mannitol injection is sometimes the key step for the delivery of chemotherapeutic drugs to brain tissue. BBB disruption (BBBD) with mannitol, however, can be highly variable and could impact local drug deposition. We use optical pharmacokinetics, which is based on diffuse reflectance spectroscopy, to track in vivo brain tissue concentrations of indocyanine green (ICG), an optical reporter used to monitor BBBD, and mitoxantrone (MTX), a chemotherapy agent that does not deposit in brain tissue without BBBD, in anesthetized New Zealand white rabbits. Results show a significant increase in the tissue ICG concentrations with BBBD, and our method is able to track the animal-to-animal variation in tissue ICG and MTX concentrations after BBBD. The tissue concentrations of MTX increase with barrier disruption and are found to be correlated to the degree of disruption, as assessed by the ICG prior to the injection of the drug. These findings should encourage the development of tracers and optical methods capable of quantifying the degree of BBBD, with the goal of improving drug delivery.
Estimating forest biomass in the USA using generalized allometric models and MODIS land products

[1] Spatially-distributed forest biomass components are essential to understand carbon cycle and the impact of biomass burning emissions on air quality. We estimated the density of forest biomass components (foliage biomass, branch biomass, and aboveground biomass) at a spatial resolution of 1 km across the Contiguous United States using foliage-based generalized allometric models and Moderate-Resolution Imaging Spectroradiometer (MODIS) land data. The foliage biomass for each forest type was calculated from MODIS leaf-area indices, land cover types, and vegetation continuous fields. The foliage-based models were developed using available diameter-based allometric equations and used to estimate branch biomass and aboveground biomass. The resultant aboveground biomass density matches well with the data from Forest Inventory and Analysis program at both state and pixel levels.
Reconstruction of embedded absorbers in random media with applications in noninvasive 3D imaging of skin lesions

An optical backscatter measuring instrument called a Nevoscope is being developed to non- invasively determine 3D characteristics of skin lesions with applications in the diagnosis of malignant melanoma. Optical images are obtained by transilluminating the lesion and imaging backscattered radiation emanating from the skin surface. Such emission profiles contain information about the absorption characteristics of sub-surface structures. It is conceivable that such profiles can be used to reconstruct structural information of inhomogeneities such as mole embedded in the skin. Monte Carlo simulations of photon migration are performed to simulate the radiation pattern of backscattered radiation imaged at the surface of the medium when a light source is placed directly on the surface of the medium. In particular, simulations are performed on media with single embedded absorbers. This is the simplest model of a mole embedded in human skin. Some reconstruction algorithms based on the difference in emission profiles is the presence and absence of the absorber, are tested. A prototype Nevoscope presently being used for visual examination is described. Heuristic reconstruction schemes using images obtained from the Nevoscope are also presented.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Loose-part mass and energy estimation

Abstract Expressions for loose-part momentum and impact force were derived as functions of plate bending wave surface acceleration and primary frequency content. These relationships were used to constrain the loose-part diagnostic problem so that loose part mass and impact energy can be determined for credible values of contact radius. Uncertainties associated with unknown contact radius were evaluated by simulation, and experimental data were analyzed for multiple energy impacts by metal spheres having mass between 0.15 and 32 lbs. Significant biases were found to exist when using apparent impact contact time information based on the two-dimensional Lamb wave model. Using the mass estimation method and bias estimates, an iterative technique was developed that converges to close to the theoretical contact time. The results provide methods for loose-part mass and energy estimation and for evaluating the effects of uncertainty in loose part location and signal transmission attenuation.
Global atmospheric circulation experiments on an Earth with polar and tropical continents

Two general circulation models forced by mean annual insolation and having an energy balance ocean have been run on an Earth with polar continents and a tropical continent. Polar continents produce strong meridional temperature gradients and a maximum hydrological cycle. A tropical continent produces the warmest planet and a minimal hydrological cycle. Both models produce more arid continents than exist today.
Individual heterogeneity in mortality mediates long-term persistence of a seasonal microparasite

One of the primary objectives in population ecology is to understand mechanisms that allow a species to persist or to be driven to extinction. In most population models, individuals are assumed to be equivalent within any particular category such as age, sex, or morphological grouping. Individuals within such groupings, however, may exhibit considerable variation in traits that can significantly affect population trajectories. Although ecologists have long been aware of such variation, they are frequently ignored to maintain computational tractability. The few statistical models that do incorporate such heterogeneity require prohibitively large amounts of data on many individuals, making them impractical. In California’s coastal prairie, a parasitic nematode, Heterorhabditis marelatus, is an important natural enemy, whose presence determines the strength and extent of a trophic cascade. Mortality of H. marelatus is strongly influenced by habitat and seasonality, which determines long-term persistence. Prior efforts to estimate mortality have suffered from difficulty in distinguishing between measurement and process error due to limitations in experimental protocol. In this study, we eliminate measurement error in the initial population size and focus on the true nature of the heterogeneity in mortality. By including individual heterogeneity in our statistical model, we are able to understand how this species is able to persist over seasonally harsh environmental conditions. Further, we extrapolate these findings to larger population sizes and illustrate that heterogeneous survival can have a significant effect on the emergent number of survivors.
Adiabatic approximation and the other (lower) bound on the scattering length

The static approximation, which neglects the distortion of the (complex) target, that is, virtual excitations, during the collision of a particle with the target, was shown previously to give an upper bound on the scattering length when the number of bound states supported by the static and true Hamiltonians are the same. It represents an underadjustment of the target to the field of the scattering particle. It is perhaps then to be expected that the adiabatic approximation, in which the target wave function is calculated for each value of the incident particle coordinate as if the incident particle were fixed at the given point and which represents therefore an overadjustment of the target to the field of the incident particle, might provide the opposite bound, the lower bound, on the scattering length. This possibility is explored for the determination of scattering lengths. The bound property is shown to hold in cases where both the true and adiabatic Hamiltonians support the same number of bound states; some (reasonable) subsidiary conditions must also be satisfied. Possible extensions of the formulation to scattering with nonzero energy and with exchange are briefly mentioned. The theory is then applied to ${e}^{+}\mathrm{H}$ and ${e}^{+}\mathrm{He}$ scattering at zero incident energy; a reasonably accurate bound for the latter system is obtained, but the adiabatic approximation gives only a very crude, though rigorous, bound on the ${e}^{+}\mathrm{H}$ scattering length. A connection between the generalized optical potential and the adiabatic potential is derived using projection-operator techniques, thus further clarifying the physical content of the adiabatic picture. Bounds are also obtained for atom-atom and ion-atom collisions; they are interesting only if the electron-proton mass ratio is not thought of as vanishingly small. Some consideration is given to $p\mathrm{H}$ scattering. Lower bounds on electron-atom scattering lengths are more difficult to obtain.
Optimal Allocation of Testing Dollars: The Example of HIV Counseling, Testing, and Referral

Background. Health screening programs can be represented as a pathway of sequential processes: offering a test, obtaining consent, conducting the test, providing results, and linking to appropriate...
Sentinel lymph node mapping for adenocarcinoma of the colon does not improve staging accuracy.

PURPOSE: This study was designed to: determine the efficacy of sentinel lymph node mapping in patients with intraperitoneal colon cancer; and create an algorithm to predict potential survival benefit by using best-case estimates in favor of sentinel node mapping and lymph node ultraprocessing techniques. METHODS: Forty-one patients with intraperitoneal colon cancer undergoing colectomy with curative intent were studied prospectively. After mobilization of the colon and mesentery, 1 to 2 ml of isosulfan blue dye was injected subserosally around the tumor. The first several nodes highlighted with blue dye were identified as sentinel nodes. Additional nodes were identified by the pathologist in routine fashion by manual dissection of the mesentery. All nodes were processed in routine fashion by bivalving and hematoxylin and eosin staining. To create an algorithm to predict potential survival benefit of sentinel node mapping and lymph node ultraprocessing techniques, assumptions were made using data from the literature. All bias was directed toward success of the techniques. RESULTS: Three of 41 patients (7 percent) did not undergo injection of dye and were excluded from further analysis. Stage of disease in the remaining 38 patients was: I, n = 10 (26 percent); II, n = 15 (39 percent); III, n = 11 (29 percent); IV, n = 2 (5 percent). At least one sentinel node was identified in 30 of 38 patients (79 percent). The median number of sentinel nodes identified was two (range, 1-3). Median total nodal retrieval was 14 (range, 7-45). All nodes were negative in 26 of 38 patients (68 percent). Sentinel nodes and nonsentinel nodes were positive in 2 of 38 patients (5 percent). Sentinel nodes were the only positive nodes in 1 of 38 patients (3 percent). Sentinel nodes were negative and nonsentinel nodes were positive in 9 of 38 patients (24 percent). Thus, sentinel node mapping would have potentially benefited only 3 percent, and failed to accurately identify nodal metastases in 24 percent of the patients in our study. To create a survival benefit algorithm, we assumed the following: combined fraction of Stage I and II disease (0.5); fraction understaged by bivalving and hematoxylin and eosin staining that would have occult positive nodes by more sophisticated analysis (0.15); fraction of occult positive nodes detected by sentinel node mapping (0.9); and survival benefit from chemotherapy (0.33). Thus, the fraction of patients benefiting from sentinel lymph node mapping and lymph node ultraprocessing techniques would be 0.02 (2 percent). CONCLUSIONS: Sentinel node mapping with isosulfan blue dye and routine processing of retrieved nodes does not improve staging accuracy in patients with intraperitoneal colon cancer. Even using best-case assumptions, the percentage of patients who would potentially benefit from sentinel lymph node mapping is small.
Internal Premature Browning in Cooked Steaks from Enhanced Beef Round Muscles Packaged in High-oxygen and Ultra-low Oxygen Modified Atmospheres

: Beef round muscles were injection-enhanced to 6%, packaged in high-oxygen (HiOx) or ultra-low oxygen (LoOx) modified atmospheres, stored 7 d and displayed 2 d (HiOx) or stored 16 d and displayed 1 d (LoOx) at 0 °C, and cooked to 71.1 °C. Raw internal color for steaks in HiOx was lighter, redder, more yellow and saturated, and had more oxymyoglobin and less deoxymyoglobin than steaks in LoOx (P < 0.0001). Cooked internal color of steaks from HiOx appeared prematurely brown and was darker, less red, yellow, and saturated, and had more denatured myoglobin than steaks from LoOx (P < 0.0001). This study presents conclusive evidence that modified-atmosphere packaging influences internal cooked color development of beef steaks.
Displaying IDL instances

Debugging a complex system can be aided by displaying the internal data structures manipulated by the system. We examine one generic Unix tool and four IDL-specific tools, focussing on their functionality and ability to handle large data structures gracefully.
Ribosome origins: The relative age of 23S rRNA Domains

The modern ribosome and its component RNAs are quite large and it is likely that at an earlier time they were much smaller. Hence, not all regions of the modern ribosomal RNAs (rRNA) are likely to be equally old. In the work described here, it is hypothesized that the oldest regions of the RNAs will usually be highly integrated into the machinery. When this is the case, an examination of the interconnectivity between local RNA regions can provide insight to the relative age of the various regions. Herein, we describe an analysis of all known long-range RNA/RNA interactions within the 23S rRNA and between the 23S rRNA and the 16S rRNA in order to assess the interconnectivity between the usual Domains as defined by secondary structure. Domain V, which contains the peptidyl transferase center is centrally located, extensively connected, and therefore likely to be the oldest region. Domain IV and Domain II are extensively interconnected with both themselves and Domain V. A portion of Domain IV is also extensively connected with the 30S subunit and hence Domain IV may be older than Domain II. These results are consistent with other evidence relating to the relative age of RNA regions. Although the relative time of addition of the GTPase center can not be reliably deduced it is pointed out that the development of this may have dramatically affected the progenotes that preceded the last common ancestor.
Label-free chiral detection of melittin binding to a membrane.

The study presented here describes an innovative approach for the detection of surface-confined proteins using chiral second harmonic generation (C-SHG). A unique optical geometry has been employed which allows for the separation of the chiral and achiral nonlinear response. By utilizing this optical arrangement, the detection of chirality originating from melittin adsorbed to a planar supported lipid bilayer has been performed for the first time by C-SHG. Melittin binding to the membrane was monitored as a function of bulk concentration through detection of the C-SHG signal. Analysis of the C-SHG adsorption isotherms reveals Frumkin adsorption behavior with a positive interaction energy. The binding constant (Ka) obtained was determined to be (8.3 ± 1.0) × 105 M-1. The results of these studies have far-reaching implication in the use of C-SHG for the label-free detection of protein association to surfaces and in the analysis of protein interfacial phenomena.