cssi/SciSciGPT-SciSciNet huggingface dataset:
The effect of pressure on block copolymer micelle formation: fluorescence and light scattering studies of poly(styrene-b-ethylene propylene) in heptane

Abstract Pressure dependent excimer fluorescence and dynamic light scattering measurements are made on poly(styrene-b-ethylene propylene) (PSPEP) diblock copolymers that form micelles in the selective solvent n-heptane. We determine the critical micelle temperature (cmt) as a function of block copolymer concentration and applied pressure up to 200 MPa by monitoring the excimer emission band energy, which passes through a minimum at the cmt. The photophysical determination of cmt agrees with simple turbidity measurements taken under the same conditions. The hydrodynamic radius, as determined by dynamic light scattering, increases approximately 5% for a PSPEP diblock copolymer having PS Mw = 35 000 and PEP Mw = 61 000, denoted PSPEP 35 61 , with increasing pressure. At 298 K, the hydrodynamic radius decreases approximately 4% for the PSPEP diblock copolymer with PS Mw = 21 000 and PEP Mw = 66 000, denoted PSPEP 21 66 . These size changes are consistent with a negative volume change upon micellization for PSPEP 35 61 and a positive value for PSPEP 21 66 . For temperatures greater than 308 K, both block copolymers exhibit positive volume changes upon micellization. Using a simple corresponding states thermodynamic model, we relate the pressure effects to a decrease in the PS/heptane interaction parameter, i.e. an increase in the solvent quality with increasing pressure.
Point mutations in the P30 domain of thegag gene of moloney murine leukemia virus

Abstract A series of point mutations in the P30 domain of the Moloney murine leukemia virusgag gene was generated by bisulfite treatment of heteroduplex DNAS containing a single-stranded region in thegag gene. One virus bearing such a mutation exhibited a coordinate defect ingag andpot function, and was similar to previously described deletion mutants with alterations in this gene. One mutant virus displayed a different phenotype: it could assemble virion particles and providepol function, but the particles were defective in the early stages of infection. The continued concordance of the mutants' failure or ability to both assemble virions and providepollends further support to the proposal that similar parts of thegag gene are required for these two processes.
Hierarchy and Work Dissatisfaction in a Chilean Hospital

At a major hospital of the Chilean National Health Service, staff members of the Departments of Medicine and Surgery who had daily contact with in-patients were interviewed. Respondents ranged from physicians to ward maids. The analysis dichotomizes them as professionals and nonprofessionals. Members of both groups who reported that physicians were hard to approach were less satisfied with their work, in particular feeling that they were less able to exert much control over it. Professionals feeling less able to control their work reported more frequent thoughts of quitting, and of their work being unrewarding. Such associations occurred among nonprofessionals as well, but in addition they seemed more troubled by having to put up with errors that other subordinates had committed. Some of these findings are further considered in the light of whether respondents had traditionalistic or modernistic orientations.
Erbium:YAG Laser Photothermal Retinal Ablation in Enucleated Rabbit Eyes

The erbium:YAG laser has been shown to produce precise tissue ablation because of the high water absorption of the 2.94-μ.m wavelength emitted by this laser. We used an experimental system to create lesions of various depths in the surface of the rabbit retina in enucleated eyes in vitro to examine the potential application to maneuvers such as retinotomy and the removal of epiretinal membranes in vitrectomy. With an air/retinal interface, single pulses produced discrete craters in the retinal surface with a depth proportional to fluence, ranging from 30 μm for a pulse of 1.3 J/cm 2 to a full-thickness retinotomy at 3.9 J/cm 2 . An adjacent zone of coagulated tissue ranging in size from 15 to 40 μm was noted. Multiple pulses had an additive effect. With a fluid/retinal interface, 20 pulses of 3.6 J/cm 2 produced a full-thickness retinotomy, with an adjacent zone of damaged tissue up to 1 mm, caused by effects of volatilization of intervening fluid. The erbium:YAG laser may have a role in vitreoretinal surgery.
Hormonal regulation of PKC-δ protein and mRNA levels in the rabbit corpus luteum

We have previously reported that rabbit corpora lutea exhibit a prominent phosphorylated substrate protein at 76 kDa which corresponds to the autophosphorylated form of protein kinase C (PKC) delta and that the expression of PKC-delta protein is increased in rabbit corpora lutea of pseudopregnancy at least 2-fold when serum estrogen levels are raised by the presence of an estrogen implant inserted at the time of human chorionic gonadotropin (hCG)-induced ovulation. The purpose of the experiments described herein was to evaluate further the hormonal regulation of PKC-delta in the rabbit corpus luteum. Results demonstrate that luteal PKC-delta protein and mRNA are concomitantly induced some 5-fold within 48 h in response to an ovulatory surge of hCG; that, as in corpora lutea of pseudopregnancy, luteal PKC-delta expression is relatively constant during the life span of the corpus luteum following a fertile mating; that exogenous estrogen does not modulate the induction of luteal PKC-delta during luteinization but promotes an additional two-fold increase in steady state PKC-delta mRNA (and protein) levels in corpora lutea by day 10 of pseudopregnancy; and that luteal PKC-delta expression can be abruptly and reversibly modulated upon withdrawal and subsequent replacement of an estrogen implant to pseudopregnant rabbits. These results demonstrate that an ovulatory surge of luteinizing hormone induces the expression of PKC-delta mRNA and protein in rabbit corpora lutea, and that once the corpus luteum becomes estrogen responsive, estrogen then regulates expression of PKC-delta mRNA and protein.
Plots for examination of univariate twin data

We discuss informative plots for univariate twin data that can be used in conjunction with twin data analyses. The plots are useful for spotting outliers, spotting possible single gene effects, and displaying the contribution of individual twin pairs to the fit of genetic models of the data. We illustrate the use of the plots on bone mineral data, and present programs for generating the plots in SAS.
Effects of administrator-witness contact on eyewitness identification accuracy

Concern that lineup administrators can influence eyewitness identifications has led researchers to suggest implementing double-blind testing, an idea that police resist. Using a typical eyewitness paradigm (video event followed by photographic identification test), the present study demonstrated that an alternative technique, minimizing the level of contact between lineup administrators and witnesses, could reduce false identifications without reducing hits. Specifically, witnesses were more likely to make decisions consistent with lineup administrator expectations when the level of contact between the administrator and the witness was high than when it was low. These results are explained within the experimenter expectancy framework. Implications for applied settings are discussed.
Evaluation of Cadmium Ratio and Foil Activation Measurements for a Beryllium-Reflected Assembly of U(93.15)O2 Fuel Rods (1.506-cm Triangular Pitch)

A series of small, compact critical assembly experiments was completed from 1962 to 1965 at Oak Ridge National Laboratory’s Critical Experiments Facility in support of the Medium-Power Reactor Expe...
Acoustic communication in hybrid treefrogs: sound production by males and selective phonotaxis by females

1. The sympatric, genetically compatible treefrogs,Hyla chrysoscelis andH. femoralis, were artificially crossed (reciprocally) and the F1 hybrid progeny raised to sexual maturity in the laboratory. The calls of males and selective phonotaxis of females were studied. 2. Male hybrids began calling about seven months after the cross was made. The temporal properties of the vocalizations were intermediate, more similar to one or the other of the calls of the parental species, or unique to hybrids. Pulse period (pulse-repetition rate) was the most stereotyped temporal property and was more similar to that in the calls ofH. femoralis thanH. chrysoscelis. Dominant frequency of the calls of hybrids and both parental species was typically between 2 and 3 kHz. 3. In two-stimulus playback experiments, F1 female hybrids were selectively attracted to hybrid calls in preference to those ofH. chrysoscelis. Females did not prefer hybrid calls over those ofH. femoralis, probably because of an overlap in pulse period and a significant difference in the total amount of acoustic stimulation. When these factors were eliminated or reduced by presentation of synthetic calls, female hybrids chose a stimulus with a pulse period typical of hybrids in preference to a call with a pulse period typical ofH. femoralis. 4. There were no differences in the call structure nor in the selective phonotaxis of F1 hybrids of the reciprocal crosses, thus indicating that sex-link-age and maternal effects are probably not involved in the genetic specification of the acoustic communication system. 5. The behavioral coupling (with respect to pulse period) demonstrated in this study and in crickets is consistent with the predictions of the ‘genetic coupling’ hypothesis, which postulates that both signal generating and recognition mechanisms share common circuitry specified by the same genes. The results of these behavioral studies are sufficiently encouraging to warrant neurophysiological, anatomical and genetic experiments that can provide direct tests of the hypothesis.
Right ventricular diastolic relaxation in conscious dog models of pressure overload, volume overload, and ischemia

Abstract Objective: Limitations in clinical understanding of right ventricular relaxation can be attributed to the paucity of information from basic studies in animal models of right ventricular disease. This study examined, in the conscious state, right ventricular relaxation dynamics under normal conditions (n = 15) and in subacute (2-5 weeks) canine models of right ventricular pressure overload (n = 6), volume overload (n = 7), and free wall ischemia (n = 7). Methods: Right-heart micromanometric measurements were obtained by using multisensor catheters. A new algorithm was developed to obtain representative ensemble averages of hemodynamic waveform data sets. Right ventricular relaxation was analyzed by using an exponential model with 3 parameters: P 0 , τ, and P b . Significant changes versus control values were determined by means of analysis of variance and the Student unpaired t test with Bonferroni's adjustment. Results: In the state of pressure overload, right ventricular pressure decay exhibits an increased P 0 (56.2 ± 19.1 vs 13.1 ± 5.1 mm Hg [mean ± SD]) and prolonged τ (57.1 ± 2.8 vs 27.8 ± 3.9 ms); there is also a decreased P b (−7.9 ± 1.5 vs 0.28 ± 1.8 mm Hg). The only significant change in volume overload is an increased asymptote, P b (5.3 ± 2.9 mm Hg). In right ventricular ischemia, prolongation of τ (41.4 ± 13.0 ms) and decreased P b (−1.95 ± 1.1 mm Hg) attain high significance. Conclusions: Distinctive abnormalities in right ventricular relaxation dynamics accompany pressure overload, volume overload, and ischemia and may contribute to clinical right ventricular dysfunction. J Thorac Cardiovasc Surg 2002;124:964-72
A cost-effective thoracoscopic treatment strategy for pediatric spontaneous pneumothorax.

Background: Recent data suggest that children have a higher incidence of recurrence than adults after nonoperative treatment of primary spontaneous pneumothorax (PSP). Video-assisted thoracoscopic surgery (VATS) allows efficacious therapy with significantly less morbidity. We attempt to define the most cost-effective clinically efficacious strategy using VATS to manage pediatric PSP. Methods: We retrospectively reviewed all admissions to a tertiary care children's hospital for PSP between January 1, 1991 and June 30, 1996. Results: Fifteen children had 29 primary or recurrent PSPs. Mean patient age was 14.8 ± 1.1 years, boy–girl ratio 4:1, median body mass index 18 (normal, 20–25), and 67% of pneumothoraces left sided. All patients were managed initially nonoperatively: 14 with tube thoracostomy drainage and 1 with oxygen alone. Of the children initially managed nonoperatively, 57% had a recurrent pneumothorax, and 50% of these patients eventually developed contralateral pneumothoraces. Nonoperative treatment for recurrence resulted in a 75% second recurrence rate. In contrast, eight children who underwent operative management had a 9% incidence of recurrence. The total for charges accrued in treating 29 pneumothoraces in these 15 patients was approximately $315,000. In the same population, the estimated charges for initial nonoperative therapy followed by bilateral thoracoscopy after a single recurrence would be $230,000. Conclusions: A cost-effective treatment strategy for pediatric primary spontaneous pneumothorax is tube thoracostomy at first presentation, followed by VATS with thoracoscopic bleb resection and pleurodesis for patients who experience recurrent pneumothorax.
Competitive intelligence systems: qualitative DSS for strategic decision making

Technologies such as decision support systems (DSS) are helpful in solving many kinds of problems, especially those that are based on quantitative data and/or are tactical in scope. For strategic decisions, however, decision makers can benefit greatly from a tool that tracks and organizes qualitative and other nebulous information. Such a tool would help cultivate and leverage an organization's intellectual assets to help users address decision making in a more informed fashion. While DSS technologies have not commonly been used in such situations, they can be adapted to do so. This paper addresses the development of a qualitative DSS in a health care setting that allowed hospital administrators to exploit the qualitative information obtained by its network of field representatives for strategic benefit. This type of system, and its corresponding benefits, can be extended to other business situations.
Early history of scleractinian corals and its geological consequences

Conventional views have implied that scleractinian corals were hermatypic and thus were potentially reef building from the onset of their appearance in early Mesozoic time in shallow-shelf carbonate environments. However, for almost 25 m.y. they held rather subordinate positions and generally did not participate in extensive ecologic reef framework. Evidence from both North America and Europe demonstrates that Triassic corals had ecologic preferences quite different from those in the Cenozoic. A key step in the evolutionary success of these corals may have been the advent of a symbiotic association with algae. This association, believed to have developed at the end of the Triassic, could have been responsible for thrusting scleractinians into prominent positions as reef builders and may account for their dramatic radiation in Mesozoic time.
Crosstalk Characteristics Of Multichannel Acousto-Optic Bragg Cells

ABSTRACT A detailed characterization of crosstalk was carried out for two 32~channel. TeOa Bragg cells: one operated at 95 MHz, the other at 400 MHz. A survey showed that the two cells were state-of-the-art devices. Crosstalk was visualized and measured radiometrically in a Schlieren imaging setup. Both qualitative and quantitative results were obtained. Results showed that, when neighboring channels were activated, acoustic crosstalk due to beam spreading was the major source, especially when all the channels are driven by co­ herent rf signals. Acoustic crosstalk varies from zero at the transducer to about 10 dB below the maximum beam intensity. Radio frequency crosstalk was also measured. It amounted to -25 dB in the 95-MHz cell and -35 dB in the 400-MHz cell. Possible methods of further reducing the crosstalk were given and suggestions for future work were made. 1. INTRODUCTION Multichannel bulk acousto-optic (AO) Bragg cells have been proposed in many applications since 1962. They include signal processing of phased array antennas1 "6, multichannel rf spectrum analysis7"9 , wideband printing and page composing 10'14, correlation and matched filtering6-15"16. real-time Fourier transformation17, and optical computing18"21. The realization of many of these applications depends on the availability of special multi­ channel AO Bragg cells, which, in turn, rely heavily on AO material development and fabrication technique advancement. Because of potential payoffs in many of these applications, efforts toward the development of these key devices have been made in the form of both modulators and deflectors. Table 1 gives the history of bulk acousto- optic Bragg cell development and some relevant technical information, based on a survey of the open literature.Table 1. Survey of Multichannel Bulk Acousto-optic Bragg Cells in the Open Literature
Design and analysis of an adaptive transcutaneous power telemetry for biomedical implants

Inductively coupled coil pair is the most common way of wirelessly transferring power to medical implants. However, the coil displacements and/or loading changes may induce large fluctuations in transmitted power into the implant if no adaptive control is used. In such cases, it is required to transmit excessive power to accommodate all the working conditions, which substantially reduces the power efficiency and imposes potential safety concerns. We have implemented a power transfer system with adaptive control technique to eliminate the power variations due to the loading or coupling coefficient changes. A maximum of 250mW power is transmitted through an optimized coil pair driven by Class-E power amplifier. Load shift keying is implemented to wirelessly transfer data back from the secondary to primary side over the same coil pair, with data rate of 3.3 kbps and packet error rate less than 10/sup -5/. A pseudo pulsewidth modulation has been designed to facilitate back data transmission along with forward power transmission. Through this back telemetry the system transmits the information on received power, back from implant to primary side. According to the data received, the system adjusts the supply voltage of the Class-E power amplifier through a digitally controlled dc-dc converter, thus varying the power sent to the implant. The key system parameters are optimized to ensure the stability of the closed-loop system. Measurements show that the system can transmit the 'just-needed' power for a wide range of coil separation and/or loading conditions, with power efficiency doubled when compared to the uncompensated link.
PHARMACOLOGY OF PEDIATRIC RESUSCITATION

The resuscitation of children from cardiac arrest and shock remains a challenging goal. The pharmacologic principles underlying current recommendations for intervention in pediatric cardiac arrest have been reviewed. Current research efforts, points of controversy, and accepted practices that may not be most efficacious have been described. Epinephrine remains the most effective resuscitation adjunct. High-dose epinephrine is tolerated better in children than in adults, but its efficacy has not received full analysis. The preponderance of data continues to point toward the ineffectiveness and possible deleterious effects of overzealous sodium bicarbonate use. Calcium chloride is useful in the treatment of ionized hypocalcemia but may harm cells that have experienced asphyxial damage. Atropine is an effective agent for alleviating bradycardia induced by increased vagal tone, but because most bradycardia in children is caused by hypoxia, improved oxygenation is the intervention of choice. Adenosine is an effective and generally well-tolerated agent for the treatment of supraventricular tachycardia. Lidocaine is the drug of choice for ventricular dysrhythmias, and bretylium, still relatively unexplored, is in reserve. Many pediatricians use dopamine for shock in the postresuscitative period, but epinephrine is superior. Most animal research on cardiac arrest is based on models with ventricular fibrillation that probably are not reflective of cardiac arrest situations most often seen in pediatrics.
Hepatoerythropoietic porphyria in a woman with short stature and deformed hands.

A 23-year-old woman from Honduras was diagnosed to have hepatoerythropoietic porphyria. She had photosensitive skin of early onset, hypertrichosis, and severe scleroderma-like lesions of the hands. Erythrocyte uropor-phyrinogen decarboxylase activity was reduced to about 10% of the normal activity. © Wiley-Liss, Inc.
Prevalence of the fourth heart sound by phonocardiography in the absence of cardiac disease.

Abstract A blinded, prospective study of phonocardiograms revealed a fourth heart sound (S 4 ) in 181 of 245 consecutively examined ambulatory subjects in sinus rhythm aged 50 to 80 years whose clinical status was unknown until all graphic studies were tabulated. An S 4 was demonstrated in 113 (73.1 per cent) of 152 individuals with and 68 (74.3 per cent) of 93 individuals without evidence of cardiovascular disease, statistically an equal prevalence. S 4 in older persons appears to be "normal" phenomenon.
On SAR Imaging through the Earth's Ionosphere

We analyze the effect of dispersion of radio waves in the Earth's ionosphere on the performance (image resolution) of spaceborne synthetic aperture radars (SARs). We describe the electromagnetic propagation in the framework of a scalar model for the transverse field subject to weak anomalous dispersion due to the cold plasma. Random contributions to the refraction index are accounted for by the Kolmogorov model of ionospheric turbulence. A key consideration used when analyzing the statistics of waves is normalization of the probability distributions for long propagation distances. The ionospheric phenomena, both deterministic and random, are shown to affect the azimuthal resolution of a SAR sensor stronger than the range resolution; also, the effect of randomness appears weaker than that of the baseline dispersion. Specific quantitative estimates are provided for some typical values of the key parameters. Probing on two carrier frequencies is identified as a possible venue for reducing the ionospheric distortions.
A new matrix identity in control theory

In this paper, a new matrix identity is presented, which gives an insight into some fundamental concepts of a multivariable control system and makes many results easy to prove and understand.
Equivalence of the tampered random variable and the tampered failure rate models in accelerated lifetesting for a class of life distributions having the ‘setting the clock back to zero property'

It is well-known that Nelson's (1980) Cumulative Exposure (CE) model in a step-stress accelerated life test is equivalent to the Tampered Random Variable (TRV) model of DeGroot and Goel (1979) if the life distributions under the two stresses belong to the same scale-parameter family. In the present paper, it is proved that if a step-stress accelerated life test is performed on a population of units whose life distribution belongs to a class of life distributions having the ‘setting the clock back to zero’ property, (see B.R. Rao and Talwaker 1989, 1990 and B.R. Rao 1990a), then the TRV is equivalent to the Tampered Failure Rate (TFR) model of Bhattacharyya and Soejoeti (1989). The proof of the necessity is simple. Simple examples of the family of life distributions with this property include the exponential, the linear hazard exponential and the Gompertz distributions. The Weibull distribution does not have this property and it is demonstrated that the TRV and the TFR models lead to different surival dist...
Forward to the Past: Wolves in the Northern Rockies and the Future of ESA Politics

As the 30th birthday of the Endangered Species Act (ESA) passes and the act moves toward middle age, it is possible to discern a new generation of ESA-related issues. One of these is the management of the small number of species that have recovered or will recover to the point where they can be delisted. The delisting of some species raises two important questions that are the focus of this article. First, how will the delisting of species affect the relationship between state governments and the federal government? Second, how will state efforts to manage delisted species seek a balance between utilitarian and ecological values? This article examines the planned delisting of the gray wolf in the northern Rocky Mountains and three state management plans (Idaho, Montana, and Wyoming). It argues that the compromises entailed in these management plans suggest a sense of the future direction of the politics of species conservation.
Liver peptide stabilizing factor protects phosphofructokinase against inactivation by fructose-1,6-bisphosphatase.

Abstract Rabbit liver fructose-1,6-bisphosphatase (FDPase) can reversibly inactivate both rabbit muscle and rat liver phosphofructokinases (PFK) under appropriate conditions. The peptide factor which stabilizes rat liver PFK-L 2 against thermal inactivation has now been found to protect both PFKs from inactivation by FDPase. Assay at high ATP (ca. 3 mM) is necessary to demonstrate these reversible changes. In addition, the activation of FDPase by liver cytosol, by oleate plus cytosol, or by oleate plus muscle PFK is lowere about 50% in the presence of peptide factor. These observations suggest an active participation of the peptide factor in regulation of liver glycolysis and gluconeogenesis.
A nearby inverted repeat of the terminal sequence of herpes simplex virus DNA.

Abstract When herpes simplex virus DNA is digested with λ-exonuclease, annealed, and then mounted for observation in the electron microscope, two types of molecules are seen. One type is circular DNA which forms because the enzyme has revealed the terminal repetition. The other type is full length linear duplex DNA with a short single-stranded loop on one end. This latter type, which apparently represents a fold-back reaction, forms because there is a nearby inverted repeat of the terminal sequence of herpes simplex virus DNA.
Genetic recombination and directional selection for DDT resistance in Drosophila melanogaster

It is generally agreed that recombination offers a long-term evolutionary advantage1,2. It is argued, however, that because genetic variability exists for recombination rates in natural populations, response to immediate demands for adaptation should result in reduced recombination regardless of the long-term consequences. Nevertheless, genetic recombination persists. Numerous models have been developed to examine this fact1,2. There exists, however, a notable lack of empiricism on the recombination question. Here we demonstrate in Drosophila that the response of a polygenic character (DDT resistance) to directional selection is sufficiently correlated with the genetic variability generated by recombination to bring about a corresponding increase in recombination rate. We draw attention to the relationship of these results to existing models, notably the ‘hitch-hiking’ model3.
Cholesterol crystal embolization presenting as either solid or cystic pancreatic lesion

Cholesterol crystal embolization (CCE) can result in end-organ ischemia. Retrospective review of clinicopathologic data. The first patient was anticoagulated with coumadin for chronic atrial fibrillation and presented subacutely with a solid mass. The second patient suffered from coronary artery disease post-angioplasty/stenting and presented with acute pancreatitis and pancreatic cystification. CCE should be considered in patients with significant vascular disease, arrhythmias or vascular manipulation who present with a pancreatic mass.
An angular-dependent embedded atom method (A-EAM) interatomic potential to model thermodynamic and mechanical behavior of Al/Si composite materials

A new interatomic potential is developed for the Al/Si system in the formulation of the recently developed angular-dependent embedded atom method (A-EAM). The A-EAM is formulated by combining the embedded atom method potential for Al with the Stillinger–Weber potential for Si. The parameters of the Al/Si cross-interactions are fitted to reproduce the structural energetics of Al/Si bulk alloys determined based on the results of density functional theory calculations and the experimentally observed mixing behavior of the AlSi liquid alloy at high temperatures. The ability to investigate the thermodynamic properties of the Al/Si system is demonstrated by computing the binary phase diagram of the Al–Si system as predicted by the A-EAM potential and comparing with that obtained using experiments. The ability to study the mechanical behavior of the Al/Si composite systems is demonstrated by investigating the micromechanisms related to dynamic failure of the Al/Si nanocomposites using MD simulations.
j Dependence of Heavy-Ion—Induced Reactions

The ($^{16}\mathrm{O}$, $^{15}\mathrm{N}$) and ($^{12}\mathrm{C}$, $^{11}\mathrm{B}$) reactions have been studied on targets of $^{54}\mathrm{Fe}$, $^{62}\mathrm{Ni}$, and $^{208}\mathrm{Pb}$ at incident $^{16}\mathrm{O}$ and $^{12}\mathrm{C}$ energies of 104 and 78 MeV, respectively. The two reactions are observed to populate states in the residual nuclei with different strengths, depending on the $j$ values of the final states. These results are believed to be a consequence of the selection rules for these reactions and suggest that spectroscopic assignments are possible with the use of heavy-ion reactions to complement other measurements.
Principal component and decomposition analysis of multicomponent mixtures of carcinogenic fluorophores

Abstract A series of binary and tertiary mixtures of polycyclic aromatic hydrocarbons is analyzed by using principal component and decomposition analysis of molecular fluorescence spectra. The results demonstrate the ability to determine the number and identity of species that are present. Failures caused by high correlation among spectra are considered.
Determining Stochastic Airspace Capacity for Air Traffic Flow Management

Deterministic air traffic flow management (TFM) decisions—the state of the art in terms of implementation—often result in unused airspace capacity. This is because the inherent uncertainties in weather predictions make it difficult to determine the number of aircraft that can be safely accommodated in a region of airspace during a given period. On the other hand, stochastic TFM algorithms are not amenable to implementation in practice due to the lack of valid stochastic mappings between weather forecasts and airspace capacity to serve as inputs to these algorithms. To fill this gap, we develop a fast simulation-based methodology to determine the stochastic capacity of a region of airspace using integrated weather-traffic models. The developed methodology consists of combining ensemble weather forecast information with an air traffic control algorithm to generate capacity maps over time. We demonstrate the overall methodology through a novel conflict resolution procedure and a simple weather scenario gener...
Asplenia syndrome: Insight into embryology through an analysis of cardiac and extracardiac anomalies

Asplenia syndrome is characterized by complex congenital heart defects, asplenia and abdominal heterotaxy. Recent interest in the syndrome has been increased by new knowledge arising from animal models and by continuing improvements in surgical outcome in childhood. To further elucidate the embryologic timing and mechanisms of the asplenia syndrome, 32 necropsy cases were reviewed and 487 published autopsy cases were reanalyzed at the hospital. The most common congenital heart defects were atrial septal defects, common atrioventricular canals and conotruncal anomalies. With use of current information on the timing of normal development, it was hypothesized that most defects originate at Streeter Horizon XIII; patients averaged 3.2 Horizon XIII defects, more than at any other stage. Distribution was unimodal. Extracardiac anomalies also exhibited a developmental spectrum. Because the normal spleen develops by Horizon XIII, asplenia, the sine qua non of the syndrome, originates then or earlier. Abnormal pulmonary lobation occurred in 80% of cases, with right isomerism occurring most often; pulmonary branching asymmetry also originates at or before Horizon XIII. Abdominal heterotaxy occurred in 72% of cases, but the timing of origin is unclear. Anomalies of other systems, including genitourinary, musculoskeletal, endocrine, and nervous systems, develop later (typically XV to XXIII); specific anomalies were less frequent, although much more prevalent than in the general population. It is concluded that asplenia syndrome is a focal developmental disturbance in laterality which occurs primarily at Horizon XIII.
Dissipative polarization by slow electrons

Abstract Slow electrons have been found to dissipate energy through hysteresis of the polarization cloud generated by them. Evaluation of this effect will require extending a recent study to include the dependence of the cloud's structure on the electron speed. A path to such theory is outlined.
Sexual dysfunction following tram flap breast reconstruction for breast cancer: A preliminary communication

Psychological and social problems have been documented as sequelae of mastectomy. Patients may experience depression, anxiety, decreased sexual interest, negative changes in body image, fears of recurrence and concerns regarding the mastectomy site or prosthesis. Immediate breast reconstruction, using improved techniques such as the TRAM flap, have lessened the negative psychological impact of mastectomy but whether these procedures themselves result in psychologic or sexual impairment has not been reported. We, therefore, report four patients, three of whom were self-referred for psychiatric evaluation, who experienced changes in body image and sexual response after TRAM flap reconstruction. Although the TRAM flap procedure cannot be specifically implicated, the similar presentation and complaints in these four cases suggest a possible association that warrants more rigorous study.
Isolation and characterization of a novel cDNA from HL-60 cells treated with 1,25-dihydroxyvitamin D-3

A novel cDNA clone (VDUP1) has been isolated from a cDNA library constructed from mRNA obtained from HL-60 cells stimulated by 1,25-dihydroxyvitamin D-3. Northern blot analysis showed that VDUP1 cDNA hybridizes to a 2.9 kb mRNA species which is up-regulated in HL-60 cells by 1,25-dihydroxyvitamin D-3 (1,25-(OH)2D3) treatment. In vitro expression of VDUP1 cDNA produced a 46 kDa protein. A search of the GenBank database revealed that the 3′ untranslated region of VDUP1 is homologous to a sequence expressed in brain. A detailed time course study showed that the VDUP1 mRNA starts to increase at 6 h after 1,25-dihydroxyvitamin D-3 treatment, reaches a plateau at around 18 h and stays elevated for 24 h. The VDUP1 mRNA is not regulated by phorbol 12-myristate 13-acetate (PMA) in HL-60 cells. Inhibition of protein synthesis by cycloheximide does not prevent the induction of VDUP1 mRNA by 1,25-dihydroxyvitamin D-3. Cycloheximide itself increases VDUP1 mRNA levels. These results suggest that the degradation of VDUP1 mRNA is either translation-dependent or regulated by a labile protein.
Processing of microRNA primary transcripts requires heme in mammalian cells.

DiGeorge syndrome critical region gene 8 (DGCR8) is the RNA-binding partner protein of the nuclease Drosha. DGCR8 and Drosha recognize and cleave primary transcripts of microRNAs (pri-miRNAs) in the maturation of canonical microRNAs (miRNAs) in animals. We previously reported that human, frog, and starfish DGCR8 bind heme when expressed in Escherichia coli and that Fe(III) heme activates apoDGCR8 in reconstituted pri-miRNA processing assays. However, the physiological relevance of heme in miRNA maturation has not been clear. Here, we present a live-cell pri-miRNA processing assay that produces robust signals and faithfully indicates DGCR8 and Drosha activities. We demonstrate that all known heme-binding–deficient DGCR8 mutants are defective in pri-miRNA processing in HeLa cells. DGCR8 contains a previously uncharacterized heme-binding motif, “IPCL,” that is also required for its activity. Heme availability and biosynthesis in HeLa cells positively affect pri-miRNA processing and production of mature miRNA. These results establish an essential function for heme in pri-miRNA processing in mammalian cells. Our study suggests that abnormal heme biosynthesis and degradation may contribute to diseases via miRNA-mediated gene regulation networks.
As we may have thought, and may (still) think

The promise of electronic documents is long lived yet curiously uninspiring in execution. In this address I will revisit the promises and consider the progress and problems faced over the last two decades in creating the information spaces imagined by the field's founders.
D1 dopamine receptor activation required for postsynaptic expression of D2 agonist effects

D1 and D2 dopamine receptors exert synergistic effects on the firing rates of basal ganglia neurons and on the expression of stereotyped behavior in rats. Moreover, the ability of D2 agonists to induce changes in basal ganglia single unit activity and spontaneous motor activity is dependent upon the presence of endogenous dopamine to stimulate D1 receptors; in rats treated with alpha-methyl-rho-tyrosine to reduce endogenous dopamine levels, the neurophysiological and behavioral effects of the D2 agonist quinpirole are significantly attenuated, while the effects of nonselective agonists like apomorphine, which stimulate both D1 and D2 receptors, or combinations of a D2 agonist and a D1 agonist are not attenuated. Thus, the previously held view that D2 receptors alone are responsible for evoking the changes in behavior and basal ganglia output induced by nonselective dopamine agonists and endogenous dopamine is not supported by these results, which indicate that these phenomena require concurrent stimulation of both dopamine receptor subtypes.
Dishonest Deed, Clear Conscience: When Cheating Leads to Moral Disengagement and Motivated Forgetting

People routinely engage in dishonest acts without feeling guilty about their behavior. When and why does this occur? Across four studies, people justified their dishonest deeds through moral disengagement and exhibited motivated forgetting of information that might otherwise limit their dishonesty. Using hypothetical scenarios (Studies 1 and 2) and real tasks involving the opportunity to cheat (Studies 3 and 4), the authors find that one's own dishonest behavior increased moral disengagement and motivated forgetting of moral rules. Such changes did not occur in the case of honest behavior or consideration of the dishonest behavior of others. In addition, increasing moral saliency by having participants read or sign an honor code significantly reduced unethical behavior and prevented subsequent moral disengagement. Although dishonest behavior motivated moral leniency and led to forgetting of moral rules, honest behavior motivated moral stringency and diligent recollection of moral rules.
THE AMERICAN BOTTOMS: THE VACANT LAND AND THE AREAL IMAGE

(1961). THE AMERICAN BOTTOMS: THE VACANT LAND AND THE AREAL IMAGE. The Professional Geographer: Vol. 13, No. 6, pp. 5-9.
Evidence for Using Clopidogrel Alone or in Addition to Aspirin in Post Coronary Artery Bypass Surgery Patients

Clopidogrel is recommended with aspirin for patients who undergo coronary artery bypass grafting (CABG) after non–ST elevation myocardial infarctions. Cardiothoracic surgeons widely use clopidogrel in addition to aspirin for post-CABG patients, including those with stable coronary artery disease. The aim of this study was to systematically review the published research to determine whether clopidogrel use after CABG is based on good trial data. Studies reporting safety and/or efficacy data for clopidogrel use with or without aspirin after on- or off-pump CABG were included. Fourteen studies met the inclusion criteria, of which 11 were reported trials and 3 are ongoing trials. Subgroup retrospective analyses of previously reported large trials of patients presenting with acute coronary syndromes (n = 1) or patients with stable coronary artery disease (n = 3) did not show a clear clinical benefit of clopidogrel when given in addition to aspirin after CABG. In contrast, there was a trend toward increased major and minor bleeding after the use of clopidogrel plus aspirin. Two small prospective trials providing data on surrogate end points and 5 small trials involving off-pump CABG patients were not of good quality to draw meaningful conclusions. In conclusion, summarized data based on subgroup analyses, surrogate end points, and observational cohort studies fail to demonstrate a clear beneficial effect of clopidogrel alone or in combination with aspirin on clinical outcomes after CABG.
SNX-111, a novel, presynaptic N-type calcium channel antagonist, is neuroprotective against focal cerebral ischemia in rabbits

Cytosolic Ca2+ overload has been proposed as a main cause of neuronal injury during cerebral ischemia. SNX-111, a synthetic product of the naturally occurring omega-conotoxin MVIIA, is a novel, presynaptic N-type Ca2+ channel antagonist and has been reported to be neuroprotective against cerebral ischemia. We studied the neuroprotective effects of SNX-111 in a rabbit model of focal cerebral ischemia. New Zealand white male rabbits (2.5-3.5 kg) were given 1 mg/kg/h i.v. SNX-111 (n=8) or normal saline (n=8) 10 min after onset of a 2-h period of transient focal cerebral ischemia induced by occlusion of the left middle cerebral, anterior cerebral and internal carotid arteries followed by 4 h reperfusion. SNX-111 significantly attenuated overall cortical ischemic neuronal damage by 44% (saline, 38.7+/-3.0%; SNX-111, 21.5+/-6.0%, P<0.05) and regions of hyperintensity on T2-weighted MRI by 30% (saline, 70.6+/-4.0%; SNX-111, 49.3+/-11.0%, P<0.05). No significant difference in (regional cerebral blood flow) rCBF or MAP (mean arterial blood pressure) was found between SNX-111- and saline-treated rabbits suggesting that neuroprotection is due to a cellular effect. We conclude that SNX-111 reduces ischemic injury in this model. Its use as a clinical neuroprotective agent for cerebrovascular surgery or stroke should be investigated further.
Issues in the design and interpretation of minimum alveolar anesthetic concentration (MAC) studies

IMPLICATIONS The two experimental designs (quantal and bracketing) used for population minimum alveolar anesthetic concentration studies give equivalent results. An expression relating variability in terms of Hill coefficients and SD is presented. Evolutionary implications of low population variability in anesthetic phenotypes is discussed.
Similarities in the helical sequences of the repressor-binding sites in the lac and lambda operators.

SEVERAL reports have considered the represser binding sites in the lac1–3 and λ4–6 operators. The analysis of these regions has focused on features apparent in the linear sequences such as regions of twofold rotational symmetry, and the 17-base-pair sequence which is largely conserved in the rightward and leftward represser-binding sites of λ6. As these sequences are thought to be wound in the double helical form when they are recognised by represser7,8, I have investigated whether any further interesting features could be revealed by such an arrangement.
Monoclonal antibodies detecting discrete epitopes of human perforin.

: Perforin is a cytolytic protein of natural killer (NK) cells and cytotoxic T cells (CTL). Purified perforin has been shown to cause cell lysis and to form stable pores in the target cell membrane, but its relevance to cytolysis in vivo is not clear. The gene for human perforin has been cloned, but monoclonal antibodies (mabs) have not been available. In order to study further its role in cytotoxicity, we have generated mabs to different regions of human perforin. Four mabs were produced from mice immunized with hybrid proteins comprising E. coli TrpE protein at the N-terminus and different regions of human perforin at the C-terminus. These proteins were made using the pATH expression plasmids into which fragments of perforin cDNA were subcloned. Monoclonal antibody PA1 was made from a mouse immunized with a hybrid protein containing the C-terminal 240 amino acids (AA) of perforin, PE1 - the N-terminal 118 AA, and PB1 and PB2 - the central 199 AA. The three plasmid constructs contained non-overlapping cDNA segments which covered the entire sequence of perforin. All mabs reacted with the immunizing hybrid protein, but not with the other hybrid proteins, indicating that at least three epitopes are recognized by this set of mabs. All mabs immunoprecipitated a molecule of about 68 kd from lysates of metabolically-labelled cytolytic large granular lymphocytic leukemia cells, but not from control lysates of non-cytolytic promyelocytic U937 cells. These mabs should be of use in determining structure-function relationships for perforin.
Effects of Ultrafiltration on Retention of Minerals and Other Components of Milk

Retentions of milk components were determined following laboratory-scale ultrafiltration using membranes of different composition and molecular weight cut-offs, milks at different stages of processing, and concentration factors of 2.0x and 1.5x. Component retentions were not affected by membrane composition, molecular weight cut-off, pasteurization or homogenization. Whole milk showed a higher percent recovery of total solids than skim milk. Pasteurized, homogenized whole milk concentrated 1.5x retained more total solids than when concentrated 2.0x, although mineral retentions were not appreciably affected. There was virtually complete retention of protein (93–100%) in all milks, while the transfer of lactose through the membranes was similar to that of water. Mineral retentions varied little from milk to milk and 2.0x retentates had individual recoveries of 16 different minerals ranging from approximately 50% to over 90%.
Design of a checkout compiler

The PL/I Checkout Compiler was designed to emphasize programmer productivity in developing programs, even at the expense of consuming extra machine resources. We explain the choices in the design of the compiler that resulted from this emphasis. The design is constrained by the requirement that a subroutine developed using this checkout compiler should be capable of executing in conjunction with code generated by a more conventional compiler. The execution environment that supports this operation is described.
A Facilitator's Guide to Career Transition Workshops for Educators.

The teaching profession is in a state of flux which will continue until changes in salaries, security, and class size are adjusted and overall attractiveness of the profession increases. The CPPC is committed to offering the Career Alternatives for Educators workshop and encourages other career centers to do so. Assisting educators in choosing to remain in teaching, or to enter another field, may help to reduce teacher burnout, enhance teacher job satisfaction, and increase their effectiveness in the classroom. In addition, the workshop provides educators with a better understanding of their University system, increases their awareness and attention to the career development process, and provides better understanding of career opportunities. Career Centers' involvement in this is particularly logical given the role which educators play in their daily interaction with potential university students as teachers or parents. For a variety of reasons, an Alternative for Educators workshop is an important outreach effort for Career Centers, and is a rewarding role for them to play.