cssi/SciSciGPT-SciSciNet huggingface dataset:
The Impact of Environmental Factors on Emergency Medicine Resident Career Choice

. Objective: To evaluate the impact of environmental factors on emergency medicine (EM) resident career choice. Methods: Program directors of all U.S. EM residencies were surveyed in November 1997. A 22-item questionnaire assessed resources allocated to research, fellowship availability, academic productivity of faculty and residents, and career choices of residency graduates. Results: The response rate was 83%. The program director (mean ± SD) estimates of resident career choice were as follows: 27.8 ± 19.1% pursued academic positions with emphasis on teaching, 5.4 ± 9.8% pursued academic positions with emphasis on research, and 66.8 ± 23.1%, pursued private practice positions. In addition, 5.70 ± 6.13% of the residency graduates were estimated to seek felloship training. Univariate analyses demonstrated that increasing departmental funding for research, having substantial resource availability (defined as having at least two of the following: dedicated laboratory space; support for a laboratory research technician/assistant, a clinical research nurse or study coordinator, a statistician, or an assistant with a PhD degree), a greater number of peer-reviewed publications by residents (r = 0.22; p = 0.08), and a greater number of peer-reviewed publications by faculty (r = 0.26; p = 0.04) positively correlated with the percentage of graduates who pursue academic research careers. Using multiple regression, however, increasing intramural funding and the presence of substantial resource availability were the only variables predictive of resident pursuit of an academic research career. Conclusion: Modification of the EM training environment may influence the career choices of graduates. Specifically, greater commitment of departmental funds and support of resources for research may enhance the likelihood of a trainee's choosing an academic research career.
The use of force-volume microscopy to examine bacterial attachment to titanium surfaces

Force-volume microscopy (FVM) was used to study the interfacial and adhesive forces affecting primary bacterial attachment to surfaces. Forces were measured for titanium surfaces immersed either in cation-enriched (CE) solutions of yeast extract amended with phosphate buffer or in control solutions lacking the cation enrichment. The FVM measurements demonstrated that regions of elevated interfacial repulsion covered 72(±2)% of the surfaces immersed in CE solutions, compared to 26(±2)% for immersion in control solutions. Parallel collection of scanning electron micrographs demonstrated that surface densities of attached Pseudomonas aeruginosa were approximately 0.62(±1.3) × 106 cells cm−2 compared to 8.7(±0.8) × 106 cells cm−2 for surfaces immersed in the CE and control solutions, respectively. Interfacial repulsion indicated by FVM measurements therefore served as a predictor of bacterial attachment. Another factor influencing bacterial attachment was the adhesion force. FVM measurements indicated that the upper fifth percentile of surface adhesion was 1784(±40) pN for surfaces immersed in the CE solution compared to 2284(±40) pN for the control solutions. The more extensive regions of elevated interfacial repulsion as well as of decreased surface adhesion provide an explanation for the lower density of attached cells observed for the surfaces immersed in the CE compared to the control solutions. The conclusion is that FVM is a sensitive and informative technique that can be used to measure and explain interactions between microorganisms and surfaces.
Music therapy and attachment relationships across the life span

Attachment refers to the quality of relationships that humans form across their life span. In music therapy, a growing body of clinical work focusing on attachment is emerging. Because participation in music therapy can promote positive and meaningful interactions over time, it creates a context for developing healthy relationships. Drawing on insights afforded from the fields of psychology and social neuroscience, the purpose of this paper is to articulate an emerging conceptual model on how music therapy interventions may target attachment across the life span. By reviewing and synthesizing current literature, the author aims to expand theoretical underpinnings that inform the work of therapists. Music-based interventions create a context-fostering attachment by: (1) supporting parent co-regulation and mutual responsiveness, (2) rebuilding capacity to form or restore relationships, (3) reducing stress and mood disturbances, (4) supporting healthy partner interactions by enhancing communication skills, a...
Current therapy for otitis media and criteria for evaluation of new antimicrobial agents.

Otitis media is the most commonly diagnosed disease in infants and children in the United States. For routine empirical treatment of uncomplicated acute otitis media, amoxicillin is the drug of choice. Persistence of signs and symptoms of infection during antimicrobial therapy calls for a change to an antibiotic effective against beta-lactamase-producing bacteria (e.g., trimethoprim-sulfamethoxazole, amoxicillin/clavulanate, or one of the newer oral cephalosporins) or performance of tympanocentesis/myringotomy or both. The most common nonsurgical and surgical methods currently employed for prevention of frequent recurrences are antimicrobial prophylaxis, myringotomy with insertion of a tympanostomy tube, and adenoidectomy. For patients who have otitis media with effusion for which treatment is indicated, antimicrobial agents have been shown to be effective; amoxicillin is preferred as initial therapy. Guidelines for evaluating new antimicrobial agents in the treatment of otitis media are presented in this report.
Do national standards indicate the need for reform in science teacher education

(1996). Do national standards indicate the need for reform in science teacher education? Journal of Science Teacher Education: Vol. 7, No. 2, pp. 85-94.
Tracking the Flow of Knowledge in IT Organizations: The Impact of Organizational Learning Factors and Project Learning Practices on Project Success

Knowledge exists at both the organizational and unit levels; environment factors at either level may enable or impede knowledge sharing within an IT organization. There is, however, no meaningful means to measure organizational or unit level knowledge sharing. The need to understand this flow of knowledge within an organization is dramatically evidenced in information technology organizations in which insufficient knowledge sharing leads to intellectual capital loss, rework, skills deterioration, and repeated mistakes that increase project costs leading to failure. The goal of the current study was to examine the relationship among knowledge sharing processes at the organizational level - organizational learning factors - the unit level - project learning practices - and the success of the IT project. Twelve organizational learning factors, eleven project learning practices, and nine project success variables were identified and validated through an expert panel review. These constructs were then codified in a survey and distributed to 5,000 IT managers. This study found a positive and significant relationship among organizational learning, project learning, and project success in IT organizations.
New folate analogs of the 10-deaza-aminopterin series. Further evidence for markedly increased antitumor efficacy compared with methotrexate in ascitic and solid murine tumor models

A group of folate analogs of the 10-deaza-aminopterin series, which were designed on the basis of the results of an intensive biochemical and pharmacokinetic program, have been examined in therapy experiments utilizing a group of murine tumor models. These new analogs were found to be markedly superior to methotrexate against four of five ascites tumors (L1210 leukemia, Sarcoma 180, Ehrlich carcinoma and Tapper carcinosarcoma) and against four of five solid tumors (S180, Tapper carcinosarcoma, E0771 mammary adenocarcinoma, Lewis lung carcinoma, and T241 sarcoma). Analogs alkylated (methyl or ethyl) at the 10 position of 10-deaza-aminopterin were found to be the most effective of the group. These analogs achieved log10 reduction in tumor burden several-fold greater in magnitude than methotrexate against L1210 and S180 ascites tumors and there were also long-term survivors. 10-Deaza-aminopterin itself gave a result intermediate between those obtained with the 10-alkyl derivatives and methotrexate. Against the solid forms of the Tapper tumor some partial regressions were obtained with methotrexate and 10-deaza-aminopterin, but a far greater number, extending over a longer period were obtained with the 10-ethyl derivative of 10-deaza-aminopterin. Against the E0771 tumor, 10-deaza-aminopterin was 2-fold and the ethyl derivative of 10-deaza-aminopterin was >5-fold more effective than methotrexate in retarding tumor growth. Evidence for partial regressions and marked effects against metastatic disease were also obtained in the case of the 10-alkyl derivative. Similar results were also obtained with the T241 sarcoma. For Lewis lung carcinoma the relative potency was about the same but overall antitumor effects were more modest.
Cooperative-competitive social orientation and school achievement among Anglo-American and Mexican-American children

Abstract Researchers have suggested that the relatively poor academic performance of Mexican-American compared to Anglo-American children may result from cultural differences in cooperative-competitive social orientation. To test the relative contribution of cooperative-competitive social orientation as a personality predictor of school achievement, the cooperativeness-competitiveness, field independence, locus of control, self-esteem, and school achievement of 45 Anglo-American and 125 Mexican-American fourth, fifth, and sixth grade children were assessed. The results indicate (1) competitiveness is positively related to school achievement among the Anglo-American children but not the Mexican-American children; (2) among the Anglo-American children competitiveness is a better predictor of school achievement than field independence, locus of control, and self-esteem; (3) the personality variables are moderately but not independently related to school achievement within both cultural groups; and (4) the between-culture variance in the personality variables does not account for the between-culture variance in school achievement. Implications of the present results for understanding within- and between-group differences in school achievement are discussed.
The vesicle transport protein Vps33p is an ATP-binding protein that localizes to the cytosol in an energy-dependent manner.

Molecular mechanisms of vesicle transport between the prevacuolar compartment and the vacuole in yeast or the lysosome in mammalian cells are poorly understood. To learn more about the specificity of this intercompartmental step, we have examined the subcellular localization of a SEC1 homologue, Vps33p, a protein implicated to function in transport between the prevacuolar compartment and the vacuole. Following short pulses, 80–90% of newly synthesized Vps33p cofractionated with a cytosolic enzyme marker after making permeabilized yeast cells. However, during a chase, 20–40% of Vps33p fractionated with permeabilized cell membranes in a time-dependent fashion with a half-time of ∼40 min. Depletion of cellular ATP increased the association rate to a half-time of ∼4 min and caused 80–90% of newly synthesized Vps33p to be associated with permeabilized cell membranes. The association of Vps33p with permeabilized cell membranes was reversible after restoring cells with glucose before permeabilization. TheN-ethylmaleimide-sensitive fusion protein homologue, Sec18p, a protein with known ATP binding and hydrolysis activity, displayed the same reversible energy-dependent sedimentation characteristics as Vps33p. We determined that the photosensitive analog, 8-azido-[α-32P]ATP, could bind directly to Vps33p with low affinity. Interestingly, excess unlabeled ATP could enhance photoaffinity labeling of 8-azido-[α-32P]ATP to Vps33p, suggesting cooperative binding, which was not observed with excess GTP. Importantly, we did not detect significant photolabeling after deleting amino acid regions in Vps33p that show similarity to ATP interaction motifs. We visualized these events in living yeast cells after fusing the jellyfish green fluorescent protein (GFP) to the C terminus of full-length Vps33p. In metabolically active cells, the fully functional Vps33p-GFP fusion protein appeared to stain throughout the cytoplasm with one or two very bright fluorescent spots near the vacuole. After depleting cellular ATP, Vps33p-GFP appeared to localize with a punctate morphology, which was also reversible upon restoring cells with glucose. Overall, these data support a model where Vps33p cycles between soluble and particulate forms in an ATP-dependent manner, which may facilitate the specificity of transport vesicle docking or targeting to the yeast lysosome/vacuole.
Health literacy skills of kidney transplant recipients.

ContextAlthough low health literacy can affect patients' treatment decision making, comprehension of health information, and medication adherence, little is known about health literacy skills of ki...
First principles assessment of perovskite dopants for proton conductors with chemical stability and high conductivity

A longstanding aim in the development of electrolytes has been to find dopants that give high proton conductivity coupled with good chemical stability. Perovskite-type oxides are useful materials for proton conduction. We used first-principles calculations to address this topic in doped BaZrO3 with efficient methods to examine a wide range of possible dopants (Y, In, Ga, Sc, Nd, Al, Tl, Sm, Dy, La, Pm, Er, and Ho). These calculations correctly identify the doped BaZrO3 materials that are already known to have favorable properties, but also identify a number of promising materials that have not been examined previously. We investigated the physical origins of the trends in chemical stability and proton mobility among the different dopants. Our data allows us to consider several possible physical descriptors for characterizing doped perovskites as proton conductors.
A semantic analysis of the design space of input devices

A bewildering variety of devices for communication from humans to computers now exists on the market. In this article, we propose a descriptive framework for analyzing the design space of these input devices. We begin with Buxton's (1983) idea that input devices are transducers of physical properties in one, two, or three dimensions. Following Mackinlay's semantic analysis of the design space for graphical presentations, we extend this idea to more comprehensive descriptions of physical properties, space, and transducer mappings. In our reformulation, input devices are transducers of any combination of linear and rotary, absolute and relative, position and force, in any of the six spatial degrees of freedom. Simple input devices are described in terms of semantic mappings from the transducers of physical properties into the parameters of the applications. One of these mappings, the resolution function, allows us to describe the range of possibilities from continuous devices to discrete devices, including possibilities in between. Complex input controls are described in terms of hierarchical families of generic devices and in terms of composition operators on simpler devices. The description that emerges is used to produce a new taxonomy of input devices. The taxonomy is compared with previous taxonomies of Foley, Wallace, and Chan (1984) and of Buxton (1983) by reclassifying the devices previously analyzed by these authors. The descriptive techniques are further applied to the design of complex mouse-based virtual input controls for simulated three-dimensional (3D) egocentric motion. One result is the design of a new virtual egocentric motion control.
The Influence of Hadley Circulation Intensity Changes on Extratropical Climate in an Idealized Model

Abstract Experiments have been performed using a simple global model with idealized physics and zonally symmertrical forcings to investigate the influence of Hadley circulation intensity changes on extratropical climate. The heating within the Tropics is latitudinally concentrated, while the heating in the extratropics is kept unchanged. This loads to an increase in the intensity of the Hadley circulation. As found earlier by Hou, along with the increase in the intensity of the Hadley circulation, there is a statistically significant temperature increase in the winter high latitudes. Zonal-mean diagnostics have been performed in order to identify the link between the changes in the Tropics and the extratropics. Detailed diagnosis of the heat budget shows that warming in the winter high latitudes is induced by changes in the mean meridional circulation, over the opposing cooling effects caused by changes in the eddy heat fluxes. Such a change is consistent with an equatorward shift of the jet stream and it...
Two-dimensional locally focused MRI: applications to dynamic and spectroscopic imaging

Conventional magnetic resonance images have uniform spatial resolution across the entire field of view. We recently described a method of creating MR images with user-specified spatial resolution along one dimension of the field of view. This paper presents the 2D generalization of this technique which allows the user to specify arbitrary spatial resolution in arbitrary 2D regions. These images are reconstructed from signals which sparsely sample the k-space representation of the image. Therefore, locally focused images can be acquired in less time than that required by Fourier imaging with uniformly high resolution. In this paper we show how to increase the temporal resolution of dynamic imaging (e.g. interventional imaging) by using high resolution in areas of expected change and lower resolution elsewhere. Alternatively, by matching the local spatial resolution to the expected edge content of the image, it is possible to avoid the localized truncation artifacts which mark Fourier images reconstructed from the same number of signals. For example, we show how proton spectroscopic images of the head may be improved by using high resolution in the neighborhood of scalp lipids which might otherwise cause truncation artifacts.
On the validity of orthotropic fracture model for advanced thermoplastic composites

Abstract An investigation was undertaken to determine if the orthotropic fracture model developed for homogeneous anisotropic solids can be used for advanced thermoplastic composites. Mode I delamination growth in unidirectional graphite/polyetheretherketone (PEEK) was studied. It was found that the orthotropic fracture model does not properly represent the delamination growth in this material system. The per cent deviation of experimental and predicted results using the model are 75 for K c and −1488 for G c values. These deviations are explained by critically examining the basic assumptions in the formulation of the fracture model and through careful analysis of the failure processes encountered. Multiple isolated crack growth and extensive fiber-bridging effects are present in this composite. Also, acoustic emission tests show the evidence of fiber fracture during delamination growth. It is suggested that direct experimental evaluation of K c and G c should be made for graphite/PEEK. composites.
Depression and Disability in Migraine: The Role of Pain Acceptance and Values-Based Action

Migraine is a complex neurological disorder that substantially impairs a person’s functioning and is often comorbid with depression. Currently, little is known about psychological coping strategies that may underlie disability and depression in patients with migraine. This study examines concurrent relations between depression and disability on the one hand and pain acceptance and values-based action on the other hand in patients with migraine. Ninety-three patients with migraine and depressive symptoms—being evaluated for a larger project examining the impact of a behavioral intervention on depression in patients with migraine—completed measures of depression, disability, pain acceptance, and values-based action. Using multiple regression analyses, the contributions of pain acceptance and values-based action to depression and disability were assessed. Low pain acceptance was strongly associated with depression and disability (r s 2 = .15–.37) in these patients. Low pain acceptance also explained unique variance in disability, beyond that of depression. Values-based action related modestly to depression and disability (r s 2 = .02–.07). Pain acceptance can contribute to our understanding of psychological health and functioning. An important next step would be to examine whether targeting acceptance in treatment of patients with migraine would lead to improvements in their mental health and functioning.
Design considerations for high Tc ceramic superconductors

Abstract The flux-jump stability and cryostability of model conductors based on the ceramic superconductor YBa 2 Cu 3 O 7 (YBC) are considered. The higher specific heat of materials at 80 K than at 4 K guarantees a much greater adiabatic flux-jump stability. In fact, YBC should be immune to adiabatic flux jumping in applied fields of less than about 5 T, which accounts for most fields of practical interest. As for the dynamic flux-jump stability of a model metal-matrix composite, the high thermal conductivity of YBC at 80 K is partly responsible for relieving the customary requirement for 100 μm filaments. Depending on the assumed J c dynamically flux-jump stable filaments can be many millimetres thick. The general conditions for cryostability in composite conductors are investigated as the operating temperature is increased from 4 to 80 K and as, for pool boiling coolant, liquid helium is replaced by liquid nitrogen. Finally, it is pointed out that although thick conductors will satisfy the electrical requirements for stable d.c. operation, fine filamentary subdivision will always be needed to reduce a.c. hysteretic losses under both external-field and self-field conditions.
Basic oral communication skills and the state speech association

This article examines the role of the state speech association in helping to bring about an improvement in the teaching of oral communication skills in the K‐12 curriculum.
Changes in blood flow in the skin and muscle with phototherapy.

Extract: The electrocapacitance plethysmograph with local counterpressure was adapted for measurement of total blood flow and blood flow through the muscle and skin in 20 icteric preterm infants. Measurements were recorded from each infant, before and during phototherapy. In 10 infants in study I, the incubator was set to maintain skin temperature of 36.5° initially and during phototherapy and no attempt was made to alter the incubator settings. Total blood flow was found to increase by a mean of 116% due primarily to increased skin blood flow (224%) and to a lesser extent, muscle blood flow (35%). Concomitant increases in heart rate, respiration rate, skin and incubator temperature were found, but no change was observed in rectal temperature. In 10 infants in study II, the skin temperature was kept constant at 36.5° before and during phototherapy by adjustment of incubator temperature. Significant increases, but of lesser magnitude, were observed in skin (52%) and total blood flow (37%), whereas muscle blood flow remained unchanged. Rectal temperature fell by a mean of 0.6° and respiration rate and heart rate remained unchanged. Speculation: During phototherapy both an increase in surface temperature and the direct effect of light results in augmentation of total blood flow. Increasing skin temperature appears to affect blood flow in both skin and muscle, whereas the direct effect of light from phototherapy lamps appears to affect skin blood flow only and to a lesser degree. The augmentation in skin blood flow should increase the efficiency of phototherapy. However, in small or sick infants the metabolic demands due to increasing temperature may outweigh any benefit from increasing blood flow.
CLEANING BEHAVIOUR BETWEEN THE CICHLID FISH TILAPIA RENDALLI FENDALLI BOULENGER 1896 AND THE CYPRINID, LABEO CYLINDRICUS PETERS, 1852

SUMMARY A case of interspecific cleaning behaviour is described between a cichlid host Tilapia rendalli rendalli and a Juvenile cyprinid Labeo cylindricus, in captivity. The host fish initiated the cleaning behaviour with a ‘head down’ display.
Preserved executive function in high-performing elderly is driven by large-scale recruitment of prefrontal cortical mechanisms

High-density electrical mapping of event-related potentials was used to investigate the neural processes that permit some elderly subjects to preserve high levels of executive functioning. Two possibilities pertain: (1) high-performance in elderly subjects is underpinned by similar processing mechanisms to those seen in young adults; that is, these individuals display minimal functional decay across the lifespan, or (2) preserved function relies on successfully recruiting and amplifying control processes to compensate for normal sensory-perceptual decline with age. Fifteen young and nineteen elderly participants, the latter split into groups of high and low performers, regularly alternated between a letter and a number categorization task, switching between tasks every third trial (AAA-BBB-AAA...). This allowed for interrogation of performance during switch, repeat, and preparatory pre-switch trials. Robust effects of age were observed in both frontal and parietal components of the task-switching network. Greatest differences originated over prefrontal regions, with elderly subjects generating amplified, earlier, and more differentiated patterns of activity. This prefrontal amplification was evident only in high-performing (HP) elderly, and was strongest on pre-switch trials when participants prepared for an upcoming task-switch. Analysis of the early transient and late sustained activity using topographic analyses and source localization collectively supported a unique and elaborated pattern of activity across frontal and parietal scalp in HP-elderly, wholly different to that seen in both young and low-performing elderly. On this basis, we propose that preserved executive function in HP-elderly is driven by large-scale recruitment and enhancement of prefrontal cortical mechanisms.
Cell Synchrony Techniques. II. Analysis of Cell Progression Data

CHO cells which have been sorted by mitotic detachment, centrifugal elutriation and fluorescence activated cell sorting have been followed for up to 14 hr by flow cytometry to examine their progression characteristics. Mathematical modelling techniques were used to provide quantitative estimates of the cell-cycle parameters. Mitotic detachment gives an 11.2-hr cycle time with mean transit times TG1, TS and TG2M equal to 3.2, 5.6 and 2.4 respectively. Cells prepared by central elutriation in an early G1 state have a 14-hr cycle time with TG1, TS and TG2M of 5.7, 6.0 and 2.3 hr. Populations prepared by centrifugal elutriation enriched in early S and late S and G2M have transit times of 2.7, 5.9 and 1.6 hr and 4.9, 6.7 and 2.1 hr with cycle times of 11.2 and 13.2 hr respectively. Cell sorting for a G1 population gives transit times of 9.8, 8.0 and 3.6 for an overall 21.4-hr cycle time.
Ramsey numbers for sparse graphs

Abstract We consider a class of graphs on n vertices, called ( d , f )-arrangeable graphs. This class of graphs contains all graphs of bounded degree d , and all df -arrangeable graphs, a class introduced by Chen and Schelp in 1993. In 1992, a variation of the Regularity Lemma of Szemeredi was introduced by Eaton and Rodl. As an application of this lemma, we give a linear upper bound, c ( d , f ) n , for the Ramsey number of graphs in this class, where log 2 log 2 c ( d , f ) = 24 df 5 . This improves the earlier result, given in 1983 by Chvatal et al. of a linear bound on the Ramsey number of graphs with bounded degree d , where the constant term was more that a tower of d 2's, and later extended by Chen and Schelp to include d -arrangeable graphs.
Experimental Demonstration of Statistical Stability in Ultrawideband Time-Reversal Imaging

We experimentally verify the statistical stability of ultrawideband time-reversal-based imaging of targets in discrete random media using electromagnetic waves. The measurements are carried out using a time-domain radar system that provides useful bandwidth of up to 40 GHz. We study the effect of the excitation bandwidth, discrete scatterers permittivity and fractional volume, and radar aperture size on the image stability. We also address the problem of imaging nonstationary targets in random media, where we verify the statistical stability of a differential time-reversal technique suited for tracking.
New chelating agents suitable for the treatment of iron overload

Abstract The requirements for chelating agents that are possible substitutes for desferriferrioxamine-B (DFO) are reviewed, and the candidates that have been carried the farthest with animal tests and clinical trials are briefly described. The ligands that have not been studied thoroughly but which look promising on the basis of initial screening tests, are also discussed. Of the ligands that satisfy the thermodynamic stability requirements, many have to be eliminated for biomedical reasons, such as toxicity, method of administration, and bioavailability. In some cases, possibly effective drugs have not been explored because they have not yet been given the attention warranted by preliminary tests. Thus, mono( o -hydroxybenzyl)ethylenediaminetriacetic acid, which tested well in the mouse screen, has not been further investigated. Also, N,N′ -bis(pyridoxyl)ethylenediamine- N,N′ -diacetic acid (PLED), which has been shown to be effective and low in toxicity, should be subjected to more extensive tests. Several promising new ligands have recently been synthesized and deserve further investigation. Thus, N,N′ -bis(6-methyl-3-hydroxy-2-pyridylmethyl)ethylenediamine- N,N′ -diacetic acid (EDDA-MeHP), which has the same functional groups as PLED but seems to be somewhat superior in Fe(III) affinity, is a promising candidate for Fe(III) removal. Also, N,N′ -di( o -hydroxyphenyl)ethylenediamine- N,N′ -diacetic acid (HPED), which has the same functional donor groups as HBED, and has high affinity for Fe(III), needs further exploration. A number of other new ligands deserving further study will be described: N,N′,N″ -tris(3-hydroxy-6-methyl-2-pyridylmethyl)-1,4,7-triazanonane (TACN-MeHP), which has the highest affinity for Fe(III) of any ligand, natural or synthetic; TACN-Me2HB, an analog of TACN-MeHP with hydroxybenzyl groups in place of hydroxypyridyl donors (and is considerably more hydrophobic than TACN-MeHP); and a hexadentate ligand containing three hydroxypyridinone moieties which should overcome the dilution problem (low stability at high dilution) encountered with 1,2-dimethyl-3-hydroxy-4-pyridinone (L1). Other ligands which may possibly serve as drugs for treatment of iron overload are also described.
Gauge-invariant effective potentials and Higgs boson mass bounds

The problem of defining a gauge-invariant effective potential with a strict energetic interpretation is examined in the context of spontaneously broken gauge theories. It is shown that such a potential can be defined in terms of a composite gauge-invariant order parameter in physical gauges. This effective potential is computed through one-loop order in a model with scalars and fermions coupled to an Abelian gauge theory, which serves as a simple model of the situation in electroweak theory, where vacuum stability arguments based on the scalar effective potential have been used to place lower bounds on the Higgs boson mass.
Temporal Bone Preservation in a 2600-Year-Old Egyptian Mummy

Perforated eardrums in the preserved temporal bones of a mummified Egyptian male in otherwise normal middle ears offer new evidence of acute otitis media and probable defective hearing among ancient Egyptians.
Density dependence in the organizational evolution of the American brewing industry across different levels of analysis

Abstract Using life-history data on all U.S. breweries known to ever operate from 1800 to 1988, we investigate Hannan's (1986) theory of density-dependent organizational evolution. Models of both founding and mortality rates are estimated, using specifications of organizational density at the regional, state, and city levels. Although the findings generally support the theory at the regional and state levels, we do not find the predicted relationships at the city level of analysis. We do, however, identify a hierarchically interdependent relationship between urban and rural breweries, which suggests that these two organizational populations cohere to form an ecological community.
Molecular mechanisms of constitutive activity: mutations at position 111 of the angiotensin AT1 receptor.

: A possible molecular mechanism for the constitutive activity of mutants of the angiotensin type 1 receptor (AT1) at position 111 was suggested by molecular modeling. This involves a cascade of conformational changes in spatial positions of side chains along transmembrane helix (TM3) from L112 to Y113 to F117, which in turn, results in conformational changes in TM4 (residues I152 and M155) leading to the movement of TM4 as a whole. The mechanism is consistent with the available data of site-directed mutagenesis, as well as with correct predictions of constitutive activity of mutants L112F and L112C. It was also predicted that the double mutant N111G/L112A might possess basal constitutive activity comparable with that of the N111G mutant, whereas the double mutants N111G/Y113A, N111G/F117A, and N111G/I152A would have lower levels of basal activity. Experimental studies of the above double mutants showed significant constitutive activity of N111G/L112A and N111G/F117A. The basal activity of N111G/I152A was higher than expected, and that of N111G/Y113A was not determined due to poor expression of the mutant. The proposed mechanism of constitutive activity of the AT1 receptor reveals a novel nonsimplistic view on the general problem of constitutive activity, and clearly demonstrates the inherent complexity of the process of G protein-coupled receptor (GPCR) activation.
A selection procedure for estimating the number of signal components

This paper proposes a selection procedure to estimate the multiplicity of the smallest eigenvalue of the covariance matrix. The unknown number of signals present in a radar data can be formulated as the difference between the total number of components in the observed multivariate data vector and the multiplicity of the smallest eigenvalue. In the observed multivariate data, the smallest eigenvalues of the sample covariance matrix may in fact be grouped about some nominal value, as opposed to being identically equal. We propose a selection procedure to estimate the multiplicity of the common smallest eigenvalue, which is significantly smaller than the other eigenvalues. We derive the probability of a correct selection, P(CS), and the least favorable configuration (LFC) for our procedures. Under the LFC, the P(CS) attains its minimum over the preference zone of all eigenvalues. Therefore, a minimum sample size can be determined from the P(CS) under the LFC, P(CS|LFC), in order to implement our new procedure with a guaranteed probability requirement. Numerical examples are presented in order to illustrate our proposed procedure.
Classification of microcalcifications in radiographs of pathologic specimens for the diagnosis of breast cancer.

Rationale and Objectives. Early detection of breast cancer depends on accurate classification of microcalcifications. We have developed a computer vision system that has the potential to classify microcalcifications objectively and consistently to aid radiologists in diagnosing breast cancer. Methods. A convolution neural network (CNN) was used to classify benign and malignant microcalcifications in radiographs of pathologic specimens. Digital images were acquired by digitizing radiographs at a high resolution of 21 μm × 21 μm. Results. Eighty regions of interest selected from digitized radiographs of pathologic specimens were used for training and testing of the neural network system. The CNN achieved an A z value (area under the receiver operating characteristic curve) of 0.90 in classifying clusters of microcalcifications associated with benign and malignant processes. Conclusion. Classification of microcalfications in pathologic specimens for diagosis of breast cancer was achieved at a high level in our computer vision system, which consists of high-resolution digitization of mammograms and a CNN.
Coming of Age With Quantum Information: Notes on a Paulian Idea

A passionate and personal account of the early days of quantum information and quantum computing, this unique book is a collection of more than 500 letters between the author and many of the founders of these intriguing fields. Christopher A. Fuchs is one of the most penetrating modern thinkers on the philosophical foundations of quantum mechanics. This remarkable book follows his journey as he comes to grips with the quantum world. It contains correspondence with Charles Bennett, Gilles Brassard, Rolf Landauer, N. David Mermin, Michael Nielsen, Asher Peres, John Preskill, Abner Shimony, William Wootters, Anton Zeilinger, and many others. Filled with diary entries, anecdotes, historical selections, and research ideas, this book will fascinate physicists, philosophers, and historians of science.
Vortex-Induced Vibration of a Three-Body Launch Vehicle During Ascent

Launch vehicles composed of three bodies can experience the shedding of vortices due to strong crossflow acceleration towards the center body, or core. Upon formation, the vortices obstruct the freestream flow, which diverts the local angle of attack towards the opposite side of the core, and a new pair of vortices are formed. This alternate vortex-pair shedding can induce significant pitch structural responses during transonic flight. Computational fluid dynamics (CFD) simulations have been used to illustrate the phenomenon and to generate forcing functions for structural dynamic analyses. Structural responses from these analyses are in good agreement with flight responses. This success suggests that CFD can be used for preflight predictions of the phenomenon. It also indicates that CFD can be used to supplement wind tunnel data when the test instrumentation does not adequately resolve the alternate vortex-pair shedding.© 2002 ASME
Parity nonconservation in the hydrogen atom

Abstract We investigate the possibility of observing parity nonconservation with a metastable hydrogen atom beam, by analyzing two effects which should permit detection of the 2S–2P admixture predicted by the Weinberg model.
Abrogation of the local xenogeneic graft versus host reaction by preinjection of cimetidine to the immunosuppressed host rats: An experimental model for testing preclinical immunorestorative activity in vivo

The local xenogeneic graft-vs-host reaction (XGVHR) is mediated by competent T lymphocytes. It was effectively used as a practical bioassay to assess the in vitro immunomodulatory effects of several drugs on cells derived from cancer patients. A modified version of the XGVHR model was recently developed primarily for preclinical evaluation of in vivo immunorestoration induced by experimental biological response modifiers (BRMs). A well-defined biological response modifier, cimetidine, was injected into Cytoxan-primed rats prior to their inoculation with xenogeneic human mononuclear cells. The cimetidine treatment induced a partial abrogation of the immunosuppressive effect of Cytoxan as manifested by a significant decline in the volume of the XGVHR from 115.23 ± 15.72 mm3 (positive control) to 67.3 ± 11.41 mm3 (P < 0.01). This abrogation of Cytoxan-induced immunosuppression by cimetidine was incomplete since the XGVHR without Cytoxan (negative control, saline only) was still significantly lower (45.12 ± 4.55 mm3; P < 0.01). The effect of cimetidine injection in vivo appeared to be dose dependent and did not exhibit any nonspecific toxic effect to the mononuclear cell inoculum. These results indicate that the model can serve as a useful tool in the preclinical evaluation of newly developed immunorestorative biological response modifiers.
Giganto-cellular glioblastoma of the lumbosacral spinal cord.

A case of giganto-cellular glioblastoma multiforme occurring in the lumbosacral spinal cord is described.
Statistical ensembles of virialized halo matter density profiles

We define and study statistical ensembles of matter density profiles describing spherically symmetric, virialized dark matter haloes of finite extent with a given mass and total gravitational potential energy. Our ensembles include spatial degrees of freedom only, a microstate being a spherically symmetric matter density function. We provide an exact solution for the grand canonical partition functional, and show its equivalence to that of the microcanonical ensemble. We obtain analytically the mean profiles that correspond to an overwhelming majority of microstates. All such profiles have an infinitely deep potential well, with the singular isothermal sphere arising in the infinite temperature limit. Systems with virial radius larger than gravitational radius exhibit a localization of a finite fraction of the energy in the very center. The universal logarithmic inner slope of unity of the NFW haloes is predicted at any mass and energy if an upper bound is set to the maximal depth of the potential well. In this case, the statistically favored mean profiles compare well to the NFW profiles. For very massive haloes the agreement becomes exact.
Cross sections for excitation of atomic hydrogen to the n = 2 , 3 , and 4 states by 15-200-keV protons

Cross sections for the processes H/sup +/ + H(1s) ..-->.. H/sup +/ + H* (n = 2, 3, 4) have been extracted from the energy-loss spectra of 15- to 200-keV protons by using a spectrum-fitting technique. Absolute cross sections have been obtained by normalization of the spectra to the theoretical cross section through the use of the Born approximation at 200 keV. The cross-section curves are very similar in shape with maxima at 60 keV. The results have been compared with available theoretical calculations. The n = 2 and n = 3 cross-section measurements are in very good agreement in curve shape with Glauber-approximation calculations. (AIP)
Chromatographic analysis of amino acids and primary amines with o-phthalaldehyde detection.

The applicability of the o-phthalaldehyde reaction with fluorometric detection to the simultaneous chromatographic analysis of amines and nonprotein amino acids is demonstrated. The majority of the compounds tested could be quantitatively determined with high sensitivity. The method is particularly well suited for the analysis of β-amino acids. Amino compounds lacking an α-hydrogen atom are detected with lower sensitivity, due to a lower relative fluorescence. Secondary amino compounds are undetectable with this system.
Lattice gas model for semiconductor (111) surface reconstruction

Abstract A simple lattice gas model is proposed for semiconductor (111) surface reconstruction. By signing energy parameters to the gas particles and the interaction among them we found that the local structure for the silicon (111) surface (7 × 7) reconstruction and the germanium (111) surface c (2 × 8) reconstruction should be different, and that the formation of the dimers on the surfaces plays a very important rule in the surface reconstructions. We suggest that a dimer instead of a simple adatom should be the basic building unit for the germanium (111) surface c (2 × 8) reconstruction.
Inoculation of Guinea pigs with varicella-zoster virus via the respiratory route

Guinea pigs were inoculated by the respiratory route with wild-type (Cyr) or vaccine (Oka) strain varicella zoster virus (VZV). Wild-type cell-free virus obtained by sonication produced neutralizing antibody responses in steroid-treated animals when given via the intratracheal route, and induced neutralizing antibody as well as a pneumonitis in normal animals when given via the intrabronchial (i. b.) route. A humoral response also followed i.b. instillation of cell-associated wild-type or vaccine strain VZV. Prior i.b. administration of thioglycollate or exposure to hyperoxia altered the number and function of pulmonary macrophages, respectively, but viral susceptibility of the guinea pigs was not enhanced. Both strains of VZV could be isolated from bronchial washings up to 48 hours after i.b. instillation of cell-associated virus, but neither strain was isolated thereafter from cultures of bronchial washings or explanted lung tissues.
Cost and Outcome Analysis of Home Parenteral and Enteral Nutrition

Background: Previous estimates of the cost of home parenteral and enteral nutrition (HPEN) have excluded hospitalization costs or were conducted abroad and have limited applicability in the United States. Few studies have used validated measures to determine the effect of home nutrition support on quality of life. Method: A cost and clinical outcome analysis was performed by retrospective review of charts of patients receiving HPEN from 1991 to 1996. Questionnaires to determine the influence of therapy on lifestyle (n = 41) and a general health status questionnaire, the short form 36-item survey (n = 39), were mailed to patients. Results: The annual cost per patient for parenteral solutions was $55,193 ± 30,596 (mean ± SD) based on Medicare charges and for enteral tube feedings was $9605 ± 9327. The annual cost of hospitalization ranged from zero to $140,220 in the parenteral nutrition group and from zero to $39,204 in the enteral nutrition group. The annual number of hospitalizations per patient for pati...
Fractional v. Integral Covers in Hypergraphs of Bounded Edge Size

In the early 1980's, V. Rodl proved the Erdo?s?Hanani Conjecture, sparking a remarkable sequence of developments in the theory of packing and covering in hypergraphs of bounded edge size. Generalizations were given by P. Frankl and Rodl, by N. Pippenger, and by others. In each case, an appropriatesemi-randommethod was used to “construct” the desired optimal object (covering, matching, colouring) in several random stages, followed by a greedy stage. The current work, which further generalizes some of the above results, is again probabilistic, and uses, in addition to earlier ideas, connections with so-calledhard-coredistributions on the set of matchings of a graph. For fixedk?2, H ak-bounded hypergraph, andt:H?R+a fractional cover, a sufficient condition is given to ensure that the edge cover number?(H), i.e., the size of a smallest set of edges of H with unionV(H), is asymptotically at mostt(H)=?A?Ht(A). This settles a conjecture first publicized in Visegrad, June 1991
Dielectric Enrichment of 1-(9-Anthryl)-3-(4-N,N-dimethylaniline) Propane in Hexane−Ethanol Mixtures

1-(9-Anthryl)-3-(4-N,N-dimethylaniline) propane (ADMA) is known to form an emissive “sandwich heteroexcimer” (SH) in the excited state. The SH state has a distinct emission spectrum that can be cha...