cssi/SciSciGPT-SciSciNet huggingface dataset:
Abstract A48: Optical imaging model for monitoring dynamic interactions of breast cancer cells and bone tissues in ex vivo co-cultures

Purpose: Bone is the most common site of breast cancer metastasis and model systems are needed to study aspects of this process directly at the microenvironmental level. Our goal was to establish optical imaging approaches to monitor and quantitate the dynamics of cell growth, migration and colonization in viable ex vivo co-cultures of breast cancer cells and bone tissue explants. Experimental Procedures: Femur tissues harvested from CD-1 nude mice and discarded femoral heads from human hip replacement surgeries were cultivated in 6-well tissue culture plates adjacent to 4T1 mouse mammary carcinoma or MDA-MB-231 human breast cancer cells harboring luciferase reporters. Serial bioluminescence imaging (BLI) was performed on an IVIS 50 Imaging System to quantify breast cancer cell growth, track breast cell migration toward bones, and monitor breast cell colonization of bone tissue over a period of days and weeks. Bioluminescence imaging of single breast cancer cells in these cultures was also performed over time using a prototype LV200 Bioluminescent Imaging System from Olympus. Summary of Results: BLI revealed the directed migration of breast cancer cells toward and into adjacent bone tissues within days, and documented extended colonization of bone tissues for up to several weeks. Quantitative BLI demonstrated variable growth rates for breast cancer cells grown in the presence vs. absence of bone tissues. Growth, migration and colonization varied dramatically and consistently according to the region of femur (epiphysis vs. diaphysis) used for co-culture. The variable patterns of breast cancer cell growth and migration observed in association with different anatomic regions of the femur are consistent with the presence of distinct cell populations within specific microenvironmental compartments of the bone. Migration of bone cells toward adjacent colonies of breast cancer cells was also observed. Conclusions: Cell behaviors associated with breast cancer metastasis occur reproducibly in viable, dynamic ex vivo co-cultures and can be monitored and quantified using optical imaging approaches. Because of the accelerated time course of interactions, and the immediate quantitation afforded by BLI, this model will facilitate the direct, rapid study of breast cancer cell interactions within the metastatic niche of bone tissues. This approach circumvents the prolonged time course associated with in vivo metastasis models and offers the potential for high throughput perturbation to identify and evaluate therapeutic interventions. Citation Format: Bonnie L. King, Marie Bammer, Irfan Ali-Khan, Jonathan W. Hardy, Christopher H. Contag. Optical imaging model for monitoring dynamic interactions of breast cancer cells and bone tissues in ex vivo co-cultures. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr A48.
New institutionalism and the erosion of capitalism

Recently Oliver Williamson synthesized and extended his wide-ranging contributions in a book, Economic Institutions of Capitalism (New York: The Free Press, 1985). In this article I shall argue for an intriguing prospect: that the economic institutions discussed by Williamson will erode capitalism-via a process akin to but more general than that described by Schumpeter in Capitalism, Socialism and Democracy. In a sense there is a parallel between my theme and the saying, “Crimes must pay or there would be no crimes.” Nevertheless, crimes need to be curbed, or they will undermine the society much as a proliferation of parasites will kill their hosts. Using a transaction approach to explain the success of competing economic institutions, Williamson starts out from two behavior assumptions concerning the transactors: bounded rationality (their “limited knowledge, foresight, skill and time in tackling a transaction”) and opportunism (their “incomplete or distorted disclosure of information, calculated to mislead, distort, disguise, obfuscate or confuse their counterparts”). In the case of “idiosyncratic transactions” (i.e., transactions marked by asset specificity, uncertainty, and infrequency), these behavior assumptions entail high transaction costs in the market. Efficiency considerations then induce the emergence and development of various “capitalism institutions” (i.e., contracts and firms). As an example, consider two complementary machines. Once they are installed at the same site and locked to each cheek-by-jowl, long-term contracts are needed to protect the owner of each machine from the potential opportunistic exploitation of the dependency relationship by the other owner. If it is difficult to draw up a complete contract, or if the litigation costs associated with the breach of contract are high, a preferred solution is the joint ownership of the two machines by a single firm. In this view the choice of institutions is determined ad hoc by summing the costs and benefits. Long lists of entries on the two sides of ledger may be drawn from the work of Williamson and other “New Institutionalists.” A firm, for example, is said to possess a
Solvent influence on photochemical isomerizations: Photophysics of DODCI

Abstract We have studied the photophysics of DODCI dissolved in a series of polar solvents. Through measurements of the temperature dependence of the photoisomer quantum yield, fluorescence lifetime and fluorescence quantum yields we clarify the kinetic mechanism for nonradiative decay. By measuring the isomerization rate as a function of temperature at constant viscosity we are able to separate the innuence of internal barriers and solvent viscous drag. The apparent activation energy observed in solutions is less than the sum of the internal and viscosity activation energies. This is shown to be consistent with the full Kramer's rate expression for diffusive barrier crossing. We also establish the temperature dependence of a second “direct” internal conversion process which does not lead to photoisomer formation and dominates the nonradiative decay of DODCI at low temperatures or in a rigid matrix.
CC Chemokine receptor 5 deficiency does not prevent local immune responses to adenovirus vector in islet transplant recipients.

Background CC chemokine receptor 5 (CCR5) plays an important role in mediating inflammation. We examined the effect of CCR5 on the immune response to adenovirus vectors and graft function in islet transplant model. Materials and Methods Syngeneic wild-type (WT) or CCR5-deficient (KO) mouse islets transduced with adenovirus encoding β-gal were transplanted under the renal capsule. After transplant, blood glucose, glucose tolerance, graft cellular infiltration, transgene and chemokine/receptor expression, and systemic anti-adenoviral/-β-gal immune response were evaluated. Results Diabetes was reversed in 1 d in both WT and KO untransduced recipients, while islets transduced with adenovirus failed to reverse diabetes until 10 d post-transplant in WT recipients or even longer (>15 d) in KO recipients ( P + , CD8 + cells and macrophages was observed in both WT and KO transduced grafts at 25 d. Though transgene expression was significantly reduced, insulin and β-gal expression persisted over 3 mo. Glucose tolerance was impaired in all grafts in KO recipients compared with untransduced grafts in WT recipients at 25 d post-transplant, but was equivalent at 3 mo. Early expression of CCR2 mRNA was increased in transduced grafts in both WT and KO recipients. No systemic antivector immunity was demonstrated in any recipient group. Conclusions Transduction of islets with adenovirus causes significant local inflammation in islet grafts and impairs early graft function in CCR5-deficient recipients, but long-term graft function is preserved. Thus, CCR5 absence does not prevent the local immune response to adenovirus transduction, and vector-associated graft dysfunction is not mediated by CCR5.
Evaluation of Left Ventricular Function in Cardiomyopathic Mice by Tissue Doppler and Color M‐Mode Doppler Echocardiography

Tissue Doppler imaging (TDI) and color M-mode Doppler flow propagation velocity (Vp) are used to assess cardiac function in humans, but the feasibility and applicability of these measurements to murine cardiomyopathic models of heart failure remain unclear. Left ventricular (LV) function was measured by TDI and Vp among mice exhibiting severe dilated cardiomyopathy (TOT), pressure-overload hypertrophy (TAC), and normal controls (NTG). Transmitral flow pattern in TACs and TOTs showed a restrictive filling pattern, but early diastolic mitral annulus velocity was comparable among the three studied groups. Propagation velocity in an anesthetized state was comparable in all three groups. However, while Vp increased in all three groups in the conscious state, the increase in NTGs was statistically greater than in TACs and TOTs. Collectively, results indicate that color M-mode Doppler echocardiography can be used to assess LV function in mice. Furthermore, Vp is depressed by anesthesia, a complication that can lead to misinterpretation of LV function in normal hearts.
Studies on the Nutritional Requirements of Hemolytic Streptococci. I. Effect of Various Substances Isolated from Liver Extract on Hemolytic Streptococci

Conclusion. Glutathione, thiochrome, flavin, nicotinic acid, betaine and glucosamine, in the presence of a calcium-alcoholic precipitate of a highly purified liver extract,∗∗ are clearly significant for the growth of the Dochez NYS strain of hemolytic streptococcus in a deficient medium. The presence of all these factors provides almost optimum conditions: omission of one or more decreases the amount of growth.
The aging process of naturally emitted aerosol (sea-salt and mineral aerosol) during long range transport

The aging processes of two representative natural aerosol, sea-salt and mineral aerosol, are investigated by using a box model equipped with a thermodynamic module (SCAPE). The model is shown to successfully describe the aging processes between the gas-phase anthropogenic pollutants (SO 2 ,N O x , and NH 3 ) and primary aerosol particles, including self-neutralization process/chlorine depletion in the sea-salt aerosol; formation/dissipation of carbonate and bicarbonate ions in the mineral aerosol; irreversible dynamic deposition of SO 2 and H 2 SO 4 ; and reversible thermodynamic distribution of inorganic volatile species. It is found that SO 2 and H 2 SO 4 tend to deposit onto the mode with the largest surface area, and that ammonia deposition is controlled by preceding SO 2 /H 2 SO 4 deposition. During the SO 2 /H 2 SO 4 deposition, chloride and carbonate are continuously released from the sea-salt and mineral dust particles, respectively. The findings by the model predictions are consistent with field and observational studies. ( 1999 Elsevier Science Ltd. All rights reserved.
Modulation of the hypoxic response following partial bladder outlet obstruction

Purpose: Tissue level hypoxia has been noted in animal models of partial bladder outlet obstruction. The key mechanisms linking hypoxia and obstruction induced bladder dysfunction remain unknown. 2-Methoxyestradiol is a natural derivative of 17β-estradiol and is currently used as an oncologic agent for its ability to regulate the hypoxia pathway. We investigated the ability of 2-methoxyestradiol to modulate the hypoxia response in a mouse model of bladder obstruction.Materials and Methods: A group of 5 to 6-week-old female C57BL/6 mice underwent oophorectomy and partial bladder outlet obstruction. Obstructed animals received a subcutaneous pellet of cholesterol placebo (7) or 2-methoxyestradiol plus cholesterol (7). Age matched controls underwent oophorectomy only (8). After 4 weeks the bladders of mice with partial bladder outlet obstruction and of unobstructed animals were harvested. Bladder sections (5 μm) were immunostained for Hypoxyprobe™-1, glucose transporter 1 and hypoxia inducible factor-1α. Rea...
Comparison between non-residual Al, Co, Cu, Fe, Mn, Ni, Pb and Zn released by a three-step sequential extraction procedure and a dilute hydrochloric acid leach for soil and road deposited sediment

Surprisingly little is known about the relationship between the labile phases removed by sequential extraction procedures and those liberated by single leaches that minimally impact the alumino-silicate matrix of solids. This investigation examines the relationship between the summed concentrations of Al, Co, Cu, Fe, Mn, Ni, Pb and Zn released by an optimized 3-step standardized sequential extraction procedure and those released by a single 0.5 M HCl leach. Thirty-nine representative soil and road deposited sediment samples were examined from an urban watershed, in Honolulu, Hawaii, which has been shown to have a high degree of traffic-associated pollution. Properties of samples analyzed varied widely and exhibited a range in cation exchange capacities from 7 to 59 cmolc/kg, pH values from 3.5 to 7.9, and organic C contents from 1 to 29%. Results indicate that the dilute HCl leach was slightly more aggressive than the sequential procedure as it removed significantly more Al, Cu, Fe, Mn and Ni; though no significant differences were observed between Co, Pb and Zn concentrations liberated by the two approaches. Both approaches showed limited dissolution of the crystal lattice with ⩽9% of the total Al liberated. Regardless of approach, element mobility was the same with the order being: Pb>Mn>Zn>Co≈Cu>Ni>Fe ∼ Al. Regression analysis indicated highly significant (P<0.0001) logarithmic relationships between the two digestion procedures, with coefficients of determination (r2) ⩾92% for all elements except Fe (54%) and Ni (64%). Further support for the strong relationships between elements liberated by both digestions was gained from geochemical contrasts between anomalous and background levels and concentration enrichment ratios. This was particularly true for Pb and Zn, the most anthropogenically enhanced trace metals in the watershed. All data indicated that a dilute HCl leach was a valuable, rapid, and cost-effective analytical tool in contamination assessment.
Connection between Gauge Invariance and Mass

The limit, as the bare mass vanishes, of a theory of a massive neutral vector meson interacting with charged fields is investigated. A redefinition of the charged-field operators is exhibited so that the original theory, involving a positive definite metric, goes over smoothly to a radiation gauge theory. The spectral forms for the boson two-point function are exhibited to show that the limit to a gauge-invariant theory does not restrict the interacting mass of the vector particle. A soluble example is given in which these limits can be studied in detail and in which the gauge-invariant limit describes a massive vector particle.
IL‐5 Responsive Subsets among Normal and Lymphomatous Murine B Cellsa

Two normal murine B-cell subpopulations, germinal center and coelomic B cells, and at least some of the lymphomas derived from them, respond to IL-5. In the case of normal B cells, a comitogen (DxS) is required. IFN-gamma is strongly inhibitory to proliferation of the coelomic B-cell subset but not for germinal center cells or the SJL lymphomas derived from them.
Mitotic arrest by benzimidazole analogs in human lymphocyte cultures

Published reports have suggested the possible association of mutagenic or teratogenic properties of some benzimidazole analogs with induced spindle disruption and consequent mitotic arrest. Studies were conducted to explore this correlation. Seven benzimidazole analogs were evaluated in a human lymphocyte system for ability to block mitosis at metaphase. Confirming the previously reported results, four compounds, mebendazole, parbendazole, cambendazole, and fenbendazole, caused metaphase accumulation, which we found to be dose- and time-related. Minimum effective dose for mebendazole and cambendazole was 10 microgram/ml; for parbendazole, 1 microgram/ml; and for fenbendazole, 100 microgram/ml. The drug-induced mitotic arrest is qualitatively and quantitatively similar to that produced by colcemid. No activity was observed with three other compounds, benzimidazole, thiabendazole, and oxfendazole when tested at 100 microgram/ml. Presence of absence of mitotic effects is correlated with reported teratogenicity with five out of the seven analogs. This suggests some utility of mitotic assessments for predicting teratogenicity.
Recent advances in the molecular beam epitaxy of the wide-bandgap semiconductor ZnSe and its superlattices

Properties of the wide-bandgap semiconductor ZnSe (2.7 eV) and ZnSe-based superlattices grown by molecular-beam epitaxy are reviewed. The growth and material characterization of ZnSe, grown on a variety of both lattice-matched and -mismatched substrates, is described ZnS, ZnTe, Sn(S,Se), the magnetic semiconductor MnSe, and the dilute magnetic semiconductor Zn/sub 1-x/Mn/sub x/Se have been layered with ZnSe to form a number of superlattice and multiple quantum well structures. The quantum size structures have provided for studies of interesting physical phenomena including polarized stimulated emission, exciton trapping, nonlinear exciton effects, biexciton formation, frustrated magnetic ordering, and wide visible wavelength tunability. >
The spherical gap of the graph of a linear transformation

Abstract Assume that A is a linear transformation from Cn into Cm. The spherical gap of the graph of A is θ (A g )= 2 1− 1 1+∥A∥ 2 . Here ∥A∥ is the operator norm of A.
Real-time sensor data streams

Today's observation streams of large numbers of geographically distributed sensors in geosensor networks arrive continuously at powerful servers, and users are interested in analyzing the sensor data streams in real-time. This article investigates challenges in data management that arise when massive real-time data streams become available and discusses different data management technologies for managing and analyzing real-time sensor data streams.
Parenteral supplementation with a fish-oil emulsion prolongs survival and improves rat lymphocyte function during sepsis.

Abstract Nutritional intervention with ω-3 fatty acids during trauma and infection has been shown to improve the clinical outcome of patients and the survival rate in laboratory animals. This study evaluated the effects of parenteral administration of lipid emulsions containing fish oil (FO) or soybean oil (SBO) on survival and T-lymphocyte response during sepsis. Male Sprague-Dawley rats (250–275 g) were prepared for parenteral feeding 4 d before inducing sepsis by cecal ligation and puncture (CLP). Standard resuscitation was provided with normal saline. Thirty minutes after completing CLP, sham control or CLP rats were infused continuously with saline or a parenteral diet containing SBO or a 1:1 FO:SBO emulsion. The survival rate was significantly improved in rats receiving the FO-supplemented diet, with 50% alive by 120 h in comparison with the saline-infused, chow-fed rats (0% alive by 120 h) or the SBO-fed rats (12% alive at 120 h). The T-lymphocyte response was evaluated at 24 h after CLP. Sepsis led to a decline in lymphocyte proliferation in rats infused with saline or the SBO emulsion, which was associated with a greater release of splenocyte interleukin-10, transforming growth factor-β and prostaglandin E 2 . Administering the 1:1 FO:SBO parenteral diet during sepsis improved the survival rate and prevented the sepsis-induced suppression of lymphocyte proliferation and interleukin-2 release. The FO effect on lymphocyte function was associated with decreased splenocyte release of transforming growth factor-β and prostaglandin E 2 .
Entropy Changes Due to Structural Transformation in the Graphite Anode and Phase Change of the LiCoO2 Cathode

Electrochemical-calorimetric measurements, in combination with the dc current interruption technique, were used to determine the change of entropy during discharge and charge of the Panasonic Li-ion cell CGR 18650H. The entropy coefficient dE eq /dT was found to vary from -0.6 mV K -1 in the discharged state to -0.1 mV K -1 in the fully charged state. An unexpected variation of large amplitude (from -0.1 to 0.25 and -0.75 back to -0.1 mV K -1 ) was observed in a narrow range of depth of discharge (DOD) near 0.23, between 3.95 and 4.10 V, curing charge as well as discharge. Thus, changes in the reversible heat, TAS, appear to be mainly responsible for the transient endothermic heat effect observed during discharge of these Li-ion cells, near DOD 0.23, between 4.035 and 3.975 V. This interpretation of the calorimetric measurements is confirmed by the fact that dE eq /dT measured at 4.0 V was positive (0.14 mV K -1 ). The unexpected strong variation of dE eq /dT near DOD 0.23 is due to the nearly simultaneous occurrence of a phase change in the cathode and a structural transformation (quasi-phase change) in the graphite anode.
Endocrine regulation of female contact sex pheromone production in the German cockroach, Blattella germanica

The amount of the major component of the cuticular sex pheromone, 3, 11-dimethyl-2-nonacosanone, on individual female German cockroaches, Blattella germanica (L.), as a function of age was determined by gas-liquid-chromatographic analysis. Accumulation of phermone increased with age in both virgin and mated females. During the first gono-trophic cycle, the pheromone accumulated most rapidly when oocyte growth rates were maximal (days 5–10), and least rapidly while the female carried an ootheca (days 11–32). Pheromone accumulation was similar in virgin and mated females when the same physiological stages (determined by oocyte maturation) were considered. Inhibition of Juvenile Hormone release, through allatectomy, chemicals (precocene or fluoromevalonate), or through mechanical egg case implants, suppressed or delayed pheromone production and oocyte growth. The Juvenile Hormone analogue ZR512 induced allatectomized or head-ligated females and females with chemically or mechanically inhibited corpora allata to produce pheromone and enlarge their basal oocytes. Finally, ZR512 applied to intact females stimulated pheromone production in a dose-dependent manner.
10B(n, Z) measurements in the energy range 0.7 to 5.0 MeV

Four ΔE E telescopes were used at the WNR (n,Z) station to investigate the production of charged particles from 10B. The telescope consisted of a gas proportional detector and a silicon surface barrier detector. The flux was determined using a 238U fission chamber. A clear separation of the ground state alpha group and first excited state a was not achieved due to the target thickness. Proton emission was also observed. Furthermore, the proton branch was up to an order of magnitude larger than predicted in ENDF/B-VII A simple R-matrix analysis has been performed on the available data
Inhibition of aflatoxin carcinogenesis by diethylstilbestrol in male rats.

Charles River Cesarean-Derived male rats were fed diets contaminated with aflatoxin, a potent hepatotoxin and liver carcinogen recently found to be contaminating staple food products. Rats fed diethylstilbestrol, in addition to the aflatoxin-contaminated diet, had decreased body weight and decreased incidence of tumors. Paired-feeding and feeding-to-weight studies indicated that the decreased tumor incidence associated with diethylstilbestrol was not the result of decreased food intake. These studies illustrate the extreme potency of aflatoxin and indicate that it represents a potential environmental hazard to man and domestic animals in many areas of the world. The male is more sensitive than the female to the effects of aflatoxin.
Determination of control parameters for a Radio-Frequency based crane controller

Human operators have difficulty driving cranes quickly, accurately, and safely because of the sluggish response of the massive structure and large payload swings. Manipulation difficulty is also increased by non-intuitive crane-control interfaces that consist of buttons and levers. A new type of crane-control interface allows operators to drive a crane by simply moving a small radio frequency emitter through the desired path. Real-time-location sensors track the movements of the radio tag. The tag position is used in a proportional feedback control scheme to drive the crane trolley toward the tag. Unfortunately, the crane payload usually responds with large-amplitude swings. Feedback control of the payload swing is not implemented, due to the difficulty of measuring the payload state. Instead, an input-shaping control element is used to limit swing. Simulations of the crane dynamics are used to select a good combination of feedback gains and input-shaper parameters. Experiments performed on an industrial bridge crane verify the effectiveness of the proposed control approach.
Role of Be´zier curves and surfaces in the Volkswagen CAD approach from 1967 to today

Abstract The practical usefulness of Bezier curves and surfaces in the design of car bodies at Volkswagen is described. The various approaches taken at different times are evaluated and refinements discussed.
Questionnaires and the Dissertation in Educational Administration

This study tests a model intended to help account for the prevalence of questionnaire methodologies among doctoral students in educational administration. Weaknesses of such methodologies for research on administrative phenomena are discussed, and several attributes of students and their doctoral programs are advanced as promoting these methods.
Internet Connectivity of State Health Departments: United States, 1996

A new era of public health is emerging, with the use of the Internet at the forefront. Improving the efficiency of information transfer through the use of new telecommunications tools, such as the ...
A Framework for Prognostics and Health Management of Electronic Systems

Prognostics and health management (PHM) of engineered systems have long been recognized as an important and integral part of reliable and safe performances of these systems, especially when their failures cause catastrophes. Blind system routine maintenance is no longer acceptable; it is both costly and inconvenient for system owners and/or users. Engineered systems, like humans, require health monitoring and management. We monitor the current health of these systems via diagnostics methods, and predict their future performance and remaining useful life via prognostics methods. Considerable research has been done on PHM with respect to mechanical systems, but the same is not true with regard to electronic systems. The contribution of this paper is two fold. First, it provides a review of PHM research with a focus on electronic systems. Second, it provides the context to identify a general PHM framework for electronic systems. The framework offers PHM guidelines to the research community in this area. The body of knowledge on PHM of electronic system fits well into the framework. The proposed framework draws on the authors' work on monitoring, diagnostics, and holistic product lifecycle via embedded sensors. The paper presents the extensions to the present research work.
Traffic sign luminance requirements of nighttime drivers for symbolic signs

An experiment was designed to determine the luminance contrast and background luminance requirements for recognition of negative contrast symbol signs (black on yellow) under low-adaptation luminance conditions. The effects of background complexity (two levels), symbol type (four symbols), background luminance (five levels), and luminance contrast between the symbol and its immediate sign background (six levels) were studied. The experiment was conducted in the Traffic Sign Simulator Facility of the Operator Performance Laboratory at the University of Iowa. Participants walked toward a calibrated, fixed-size sign stimulus projected on a large projection screen in the study. Two levels of performance were assessed: maximum recognition distance (threshold) and the distance at which the symbol types could be recognized with ease (confident). A total of 40 subjects, half of whom were young and half older, participated in the study. The traffic sign background luminance, luminance contrast, and symbol type were found to be statistically significant in affecting the symbol recognition distance. Observer age and background complexity were statistically nonsignificant. The difference between the threshold and confident viewing distances was also significant. The recognition performance data of four symbols is presented in terms of the visual angles subtended by the heights of the symbols for the six levels of contrasts and the five levels of background luminances.
In Vivo and In Vitro Activity by Diverse Chelators against Trypanosoma brucei brucei1

A system of prescreens and screen has been developed to select chelators as potential drugs against Trypanosoma brucei brucei EATRO 110. The chelators tested were nearly all commercially available, low molecular, and having moderate to high affinity for Fe(III). We prescreened 70 compounds showing heme-sparing or inhibitory activity in a Crithidia fasciculata growth system having excess Fe and minimal hemin. Of these, 45 were highly trypanocidal for suspensions of bloodstream T. b. brucei; criteria of activity here were immobilization, lysis, and loss of infectivity. Eighteen of the chelators highly active in the suspension prescreen were tried in T. b. brucei-infected mice. Thirteen of these chelators were curative in mice with 24-h infections, that is, they allowed survival greater than 30 days beyond the untreated controls. 3,4-Dihydroxycinnamic acid (caffeic acid), 2,9-dimethyl-1, 10 phenanthroline (neocuproine), and 2-pyridinecarboxaldehyde-2-pyridyl-hydrazone cured five out of five mice after an i.v dose of 100 mg/kg. Salicylaldehyde thiosemicarbazone cured five out of five mice at an i.p. dose of 500 mg/kg. Lesser activity was shown by several other chelators.
Influence of Inbreeding on Female Mate Choice in Two Species of Drosophila

Many organisms have been reported to choose their mates in order to increase the heterozygosity of their offspring by avoiding mating with relatives or homozygous individuals. Most previous studies using Drosophila melanogaster have used artificial chromosomes or extreme inbreeding treatments, situations unlikely to be matched in nature. Additionally, few studies have examined the interaction between female inbreeding status and her choice of mate. Using females and males from populations that had experienced either random mating or one generation of sib-sib inbreeding, we measured the preferences of females for males. Our results indicate that outbred males were chosen more often than inbred males and that this preference may be more pronounced in outbred females than in inbred ones.
A new detector for the measurement of the energy spectrum of cosmic ray nuclei in the TeV region

A new instrument for direct measurements of the individual energy spectra of heavy cosmic-ray nuclei in the energy range from 1011 to several 1014 eV shall be described. The instrument performance is discussed, using first results from a 28-hour balloon flight and from an accelerator calibration.
Generation of histamine‐releasing activity from serum albumin by medium derived from stimulated neutrophils of rat

1. Medium conditioned by rat neutrophils stimulated by N-formyl-methionyl-leucyl-phenylalanine (FMLP) has been found to generate mast cell histamine-releasing activity (HRA) when incubated with bovine serum albumin (BSA). 2. Histamine release increased as the concentration of BSA used to generate HRA was increased from 0.25 to 10 mg ml-1, as the concentration of neurotrophil conditioned medium was increased and as the concentration of FMLP used to stimulate the neutrophils was increased. Histamine release was non-cytotoxic as it was inhibited by energy deprivation or by removal of calcium and it was accompanied by degranulation. 3. HRA was detectable after 30 min of incubation with BSA and its generation continued to increase over the 18 h of our measurements. 4. Generation of HRA was dependent upon the presence of medium from stimulated neutrophils and on the presence of BSA, although plasma could substitute for BSA. Likewise, HRA could be generated from gamma-globulin although to a lesser extent than with albumin. 5. Generation was optimum at acid pH and was inhibited by prior boiling of the neutrophil conditioned medium or by the addition of pepstatin. 6. It is suggested that an enzyme(s) released from the neutrophil during stimulation acts on an albumin-like substrate to generate HRA. It is proposed that HRA is peptide in nature and may be generated during an inflammatory response.
Real-time fluorescence assay system for gene transcription: simultaneous observation of protein/DNA binding, localized DNA melting, and mRNA production.

Abstract This article describes the development of an in vitro multicolor fluorescence assay system for studying protein/DNA complex formation, transcription bubble formation, and mRNA production. These studies were accomplished using three different fluorescent spectroscopic probes: rhodamine-labeled DNA (at the 5′ position) to monitor protein/DNA complex formation, DNA internally labeled with the base analog 2-aminopurine in place of adenine to monitor transcription bubble formation, and γ-fluorophore-labeled UTP nucleotide to measure mRNA transcription rates. Combining these three assay systems allows the simultaneous determination of protein/DNA binding, localized DNA melting transitions, and mRNA production at physiological concentrations of reagents (p M –n M ) and millisecond timing resolution. The application of this multicolor fluorescence assay to Escherichia coli RNA polymerase reactions (binding, open complex formation, and mRNA production) demonstrates the importance of kinetically coupled events in gene transcription.
Children's Scientific Curiosity: In Search of an Operational Definition of an Elusive Concept.

Abstract Although curiosity is an undeniably important aspect of children’s cognitive development, a universally accepted operational definition of children’s curiosity does not exist. Almost all of the research on measuring curiosity has focused on adults, and has used predominately questionnaire-type measures that are not appropriate for young children. In this review we (a) synthesize the range of definitions and measures of children’s curiosity and (b) propose a new operational definition and measurement procedure for assessing and advancing scientific curiosity in young children. In the first part of the paper, we summarize Loewenstein’s (1994) review of theoretical perspectives on adult curiosity, and critically evaluate a wide range of efforts to create and implement operational measures of curiosity, focusing mainly on behavioral measures of curiosity in children. In the second part, we return to Loewenstein’s theory and present an argument for adopting his “information-gap” theory of curiosity as a framework for reviewing various procedures that have been suggested for measuring children’s exploratory curiosity. Finally, we describe a new paradigm for measuring exploratory curiosity in preschool children, defining curiosity as the threshold of desired uncertainty in the environment that leads to exploratory behavior. We present data demonstrating the reliability and validity of this measure, discuss initial results on developmental differences in young children’s curiosity, and conclude with a general summary and suggestions for future research.
Whois Behind That Curtain? Unveiling Potential Leverage over Pyongyang

To influence Pyongyang's strategic choices, U.S. options may be much broader than military threats or appeals to China. Here are the cultural‐political, military, and five key economic sources of potential leverage over Pyongyang today and the states that wield them.
Use of prenatal diagnosis among parents of infants with spina bifida in Atlanta, Georgia, 1976–1979

Abstract A follow-up was made of the parents of a population-based cohort of 154 infants with spina bifida who were born in Atlanta during 1972–1979. We interviewed the parents of these infants and, for pregnancies after the spina bifida-affected birth, the ratio of use of prenatal diagnosis and the rate of recurrence of spina bifida were ascertained. Among 43 pregnancies which occurred in 1976 or later, and which occurred after a spina bifida-affected birth, prenatal diagnosis was used for 27 pregnancies (63%). For whites, among full siblings born after a spina bifida-affected birth, the recurrence rate for spina bifida was 2% ( 1 51 ). For blacks, among seven full siblings born after a spina bifida-affected birth, none was affected. Prenatal diagnosis appears to be well accepted among these parents of infants with spina bifida.
Surgical procedure for collecting ovary samples from Rana catesbeiana

Abstract A surgical technique for extracting ovary samples from bullfrogs without altering ovarian development is described.
The sorption properties of as-synthesized and calcined MCM-41 and MCM-48

The benzene sorption capacity of as-synthesized and calcined MCM-41 and MCM-48 were compared. The hydrocarbon sorption capacity increases with pore diameter for the calcined versions. As-synthesized samples sorb appreciable amounts of benzene but the quantity is invariant with respect to pore diameter. The sorption of hydrocarbon by as-synthesized M41S materials is a unique feature not observed with microporous molecular sieves.
Philosophy, structure, and examples of relegated control

With the availability of fast and economical microprocessors, effective design of systems that are immune to failure of individual or groups of sensors, actuators, or computational units is feasible. The system can be made tolerant of the failure of individual subsystems, but functions with reduced efficiency. One way to realize this design is to formulate the dynamics of the systems in larger than minimal state spaces, to process the large number of sensory inputs needed, to relegate control functions to different inputs and to provide reliable communication among the subsystems. The imbedding of the state of the system in a larger state space allows the system to have direct access to its minimal state and indirect access by computing it, hence the need for many sensors. The sensors themselves can then measure directly physical parameters of interest or indirectly by providing a processor with measurements from which the processor computes the needed parameter. This paper deals with the concept of relegation of control as a special kind of generalized nonlinear decoupling control. A structure is proposed that relegates control of specific functions to subsets of inputs. The concept is illustrated by a nonlinear robotic example where the control of constraint forces (due to contact, grip, hold, touch, etc.), control of trajectory of motion, control of stability, and control of collision avoidance are relegated to different inputs. The inputs can be the actuator outputs of force and torque applied to the mechanical system or alternatively the inputs to the actuators themselves. Any conflict in fulfilling the four functions is arbitrated at a higher level. Compromises among the functions, priorities of functions over each other and assignments of inputs in primary, secondary, or as lower contributors to function are elaborated, programmed, and stored. This structure allows integration of a certain amount of intelligence in a robotic system at the lowest level.
Methods for classification of nocturnal migratory bird vocalizations using Pseudo Wigner-Ville Transform

Many species of birds in Americas vocalize during nocturnal migration flights. Acoustic detection and classification of the calls show potential for study of the natural history of these migrant birds. In particular, information about the species' composition and number of birds involved in migration movements may be obtainable through acoustic techniques. Other methods such as radar monitoring may have capability only to assess the number, but not the composition. Mel Frequency Cepstral Coefficients-Gaussian Mixture Model-based methods (MFCC-GMM), Mel Frequency Cepstral Coefficients-Hidden Markov Model-based methods (MFCC-HMM) and spectrogram correlation-based methods have been proposed to automate the recognition/classification of the nocturnal flight calls. Here we investigate the choice of Pseudo Wigner-Ville Transform (PWVT) on MFCC-HMM-based classifier and correlation-based classifier performance. We use a collection of recordings of nocturnal flight calls of several species of thrushes and other bird species with similar calls to evaluate and compare classifiers.
The attitudes of librarians toward the servicing and use of government publications; A survey of federal depositories in four midwestern states

Abstract This study surveys the attitudes and practices of librarians relating to government publications in depository libraries of four states. Data cover characteristics of responding libraries, staffing, collection development, organization of the collection, services rendered, and self-perceived ability to assist users. The findings of this exploratory study suggest that library staff desire additional continuing education opportunities; that there is a substantial degree of uniformity of practice among different types of library depositories in dealing with documents; and, that additional in-depth research should be undertaken in many of the above areas.
Treatment and local control of primary extremity soft tissue sarcomas.

BACKGROUND AND OBJECTIVES Modern series of adult extremity soft tissue sarcomas utilize combinations of modalities in all patients. Remaining questions: 1) is it necessary to strive for wide margins in the multimodality era; 2) to use adjuvant therapy in every high-grade sarcoma? 3) Does previous partial or marginal resection seriously interfere with the definitive resection? METHODS In a retrospective review of 194 extremity soft tissue sarcomas (1977-1994), limb preservation was possible in 181/194 (93%) of cases. Patients with narrow margins received adjuvant radiation. Some patients were referred after partial (n = 39) or "complete" (n = 63) excision. RESULTS Local recurrence was observed in 181/141 (13%) of patients treated with wide or compartmental resection, and in 10 of 42 (24%) of those treated with conservative resection plus radiation (P = 0.14). The 5-year survival rate for grade III, >/=5-cm sarcomas was not significantly different (P = 0.82) with adjuvant (46%) or without (48%) adjuvant systemic chemotherapy. Five-year survival varied (P = 0.0001) according to grade. Patients referred with partial, or "complete" (63%, 38/63, had residual tumor at reoperation) excision had a local recurrence rate of 8% and 6%, and 5-year survival rates of 75% and 84%, respectively. CONCLUSIONS 1) It is important to strive for wide margins even when adjuvant radiation is intended. 2) When a wide margin is possible, adjuvant radiation may not be necessary. 3) Adjuvant systemic chemotherapy may be considered for high-grade tumors, preferably within a prospective protocol. 4) A partial or "complete" excision of the tumor before referral to a tertiary center does not appear to compromise the limb preservation, local control, or survival rates of these patients.
Mechanism for depressed cardiac function in left ventricular volume overload.

Abstract To assess the effects of left ventricular chamber volume on the mechanism of changes in left ventricular developed pressure we performed phosphorous-31 nuclear magnetic resonance spectroscopy, hydrogen-1 nuclear magnetic resonance spectroscopy with a shift reagent, two-dimensional echocardiography, atomic absorption spectrophotometry, microsphere analysis, and surface fluorometry on isovolumic isolated perfused rat heart with incremental intraventricular balloon volumes, while left ventricular pressure was concurrently monitored. A three-phasic response of developed pressure was noted: O to 100 μl balloon volumes resulted in an increase in developed pressure, whereas developed pressure remained constant at 250 μl and fell at 400 μl. Oxygen consumption and [Ca 2+ ] 1 transients followed the same pattern as developed pressure and coronary flow. Intraventricular volumes of 250 μl or greater (a volume overload) caused endocardial ischemia, a greater decrease in extracellular versus intracellular water, thinning of the left ventricular free wall, and an increase in chamber size. Mechanical pressure on the tissue, induced by the volume overload, caused ischemia as further evidenced by (1) a negative effect on developed pressure, (2) a decrease in [Ca 2+ ] 1 transients, (3) a [Ca 2+ ] 1 overload, (4) a moderate decrease in the phosphorylation potential, and (5) an increase in the oxidation-reduction state (nicotinamide-adenine dinucleotide). The high intracellular calcium associated with volume overload may have been due to both compression and ischemia, which leads to an increased number of cross-bridges in rigor, a high end-diastolic pressure, and an increase in wall stress.
Mixing for reaction injection molding II. Impingement mixing of fiber suspensions

The performance of confined impinging jet mixers on suspensions of milled glass fibers in Newtonian liquids is investigated experimentally. Also studied are the performance of these devices in conjunction with an impingement aftermixer and a rotating mechanical mixing aid. In contrast to the behavior of unfilled liquids, fiber suspensions exhibit significant large-scale mixing defects. Over the range of fiber lengths and loadings tested, large-scale mixing quality is found to be dependent on an effective Reynolds number based on the shear viscosity of the suspension at a strain rate characteristic of the length of fibers. Both mixing aids are shown to provide improved mixing quality and could be useful in situations where length of fibers. Both mixing aids are shown to provide improved mixing Quality. and could be useful in Situations where an impingement mixer alone is not adequate.
Effects of heat treatment on microstructure and texture in Ti24at%Al-11at%Nb

Abstract Hot cross-rolled sheets of Ti-24at.% -11at.%Nb are subject to heat treatments in the α 2 + β phase field and in the β phase field. Changes in microstructure are monitored by metallography while crystallographic texture is evaluated by pole figure analysis. Annealing in the α 2 + β regime produces equiaxed α 2 grains and intergranular β with little modification to the starting texture. Annealing in the β regime results in a Widmanstatten structure whose lamellar spacing depends on the cooling rate. A much sharper texture in the α 2 phase is observed. The sharpness of the β phase texture correlated with the sharpness of the α 2 texture. Hardness measurements indicate that the highest strength occurs in the fine Widmanstatten structure where rapid cooling from the β regime produces the greatest amount of microstructural refinement.
Theory of Ultrasonic Spin Echoes

A theory of ultrasonic spin echoes valid for arbitrary spin is presented. Semiclassical vector-model equations are constructed for components of the dipole and quadrupole moment tensors which are excited by ultrasonic pulses in analogy with the well-known Bloch equations. The echo amplitudes are found to depend on the wave number of the pulse, the crystal length, spin density, sound velocity, the density of the medium as well as the magnitude of the appropriate macroscopic dipole or quadrupole moment. Our numerical estimates for a number of physical systems indicate that ultrasonic-spin-echo experiments are feasible for a variety of nuclear and electronic spin systems.