cssi/SciSciGPT-SciSciNet huggingface dataset:
An Update in the Treatment of Neurologic Disorders During Pregnancy—Focus on Migraines and Seizures

When drug therapy is necessary and cannot be avoided during a pregnancy, the decision of what drug therapy is best may be difficult for the health care provider because the vast majority of drugs a...
Comparison of In-Channel Mobile-Immobile Zone Exchange During Instantaneous and Constant Rate Stream Tracer Additions: Implications for Design and Interpretation of Non-Conservative Tracer Experiments

The stream tracer experiment, including field tracer application and subsequent analysis of solute transport and storage, is an important tool in stream hydrology and ecology. However, there have been few comparisons of tracer dynamics between the commonly applied methods of instantaneous (IA) and constant rate (CRA) tracer additions. To determine whether there are fundamental differences between the two addition techniques due to surface storage zone loading and flushing during experiments, we compare longitudinal distributions of tracer dynamics of stream in-channel dead zones during IA and CRA experiments. Back-to-back IA and CRA additions were carried out in two morphologically distinct tundra stream reaches in Alaska. Dead zone tracer time series are determined by an aggregate of upstream transport and individual dead zone residence time distributions (RTDs). The dead zone breakthrough curves for both tracer addition techniques were not consistent, neither were aggregate RTDs observed in each dead zone. Flushing patterns of tracer from dead zones reveal that stream flushing after IA additions was slower than after CRA additions. However, whole-stream RTDs were similar between IA and CRA techniques in each reach. The implications of these findings are important to design and interpretation of IA and CRA stream tracer experiments, particularly those with reactive solutes whose transformations may depend on solute concentration. Thus, IA and CRA experiments may yield differing conclusions about non-conservative transport in streams because of the inherent differences in loading of transient storage zones between these two addition techniques, and potential differences in biogeochemical processing that may occur as a consequence.
Dynamic left ventricular outflow tract obstruction in apical ballooning syndrome (Takotsubo cardiomyopathy)

Patients with apical ballooning syndrome may develop dynamic left ventricular outflow obstruction due to systolic anterior motion of the mitral valve leaflet and secondary functional mitral regurgitation, causing decreased cardiac output and hypotension. If suspected, bedside echocardiography will quickly confirm this complication. Positive inotropic/chronotropic agents should be avoided as they may exacerbate outflow tract obstruction, resulting in further hemodynamic compromise.
HILBERT THETA SERIES AND INVARIANTS OF GENUS 2 CURVES

In this paper, we compute pull-backs of Siegel theta functions to the Hilbert moduli space and consider their application to generating genus 2 curves for cryptography. We express invariants of genus 2 curves such as the Gundlach invariants and Rosenhain invariants in terms of these Hilbert theta functions. A result of independent interest is a simple formula in terms of these functions for the Eisenstein series of weight 2, which is not the pull-back of any Siegel modular form of level 1. We present an algorithm to compute minimal polynomials for the invariants, including a description of CM points and how to compute them, along with numerical examples.
Variables Influencing Victim Selection in Genocide

While victims of racially motivated violence may be identified through observation of morphological features, those targeted because of their ethnic, religious, or national identity are not easily recognized. This study examines how perpetrators of genocide recognize their victims. Court documents, including indictments, witness statements, and testimony from the International Criminal Tribunals for Rwanda and the former Yugoslavia (FY) detail the interactions between victim and assailant. A total of 6012 decedents were included in the study; only 20.8% had been positively identified. Variables influencing victim selection in Rwanda included location, segregation, incitement, and prior relationship, while significant factors in FY were segregation, location, age/gender, and social data. Additional contributing factors in both countries included self-identification, victim behavior, linguistic or clothing evidence, and morphological features. Understanding the system of recognition used by perpetrators aids investigators tasked with establishing victim identity in such prosecutions.
Noxious Heat and Scratching Decrease Histamine-Induced Itch and Skin Blood Flow

The aim of this study was to assess the effect of thermal stimuli or distal scratching on skin blood flow and histamine-induced itch in healthy volunteers. Twenty-one healthy volunteers participated in the study. Baseline measurements of skin blood flow were obtained on the flexor aspect of the forearm. These measurements were compared with skin blood flow after various stimuli: heating the skin, cooling the skin, noxious cold 2°C, noxious heat 49°C, and scratching via a brush with controlled pressure. Afterwards histamine iontophoresis was performed and skin blood flow and itch intensity were measured immediately after the above-mentioned stimuli. Scratching reduced mean histamine-induced skin blood flow and itch intensity. Noxious heat pain increased basal skin blood flow but reduced histamine-induced maximal skin blood flow and itch intensity. Cold pain and cooling reduced itch intensity, but neither affected histamine-induced skin blood flow. Sub-noxious warming the skin did not affect the skin blood flow or itch intensity. These findings suggest that heat pain and scratching may inhibit itch through a neurogenic mechanism that also affects skin blood flow.
Strings in U(N) lattice gauge theory

Abstract We consider the string representation of the lattice U(N) gauge theory and derive an exact relation between Wilson loop amplitudes for contours differing from each other by infinitesimal amounts. This relation is the analogue of the Schwinger-Dyson equation in the ordinary field theory. In the limit of large N the equation appears to be linearized and implies a free and non-interacting propagation of strings.
L-Shell Ionization in Proton and Alpha Particle Collisions with Argon

We report results of coupled-state calculations of argon L-shell ionization by proton and alpha particle collisions in the 100 to 500 kev/amu energy range. Our target-centered basis includes up through f-states. We have explored the angular momentum convergence and ability of our pseudostates to describe the ionization continuum by comparing to the Born calculations of Choi; excellent agreement is obtained. In the Born we have shown the effect of using different independent-particle target potentials; these effects are large, particularly at low energy. We propose a modification of the Hartree-Fock potential that leaves all the wavefunctions and the bound orbital energies unaltered, but that lowers the continuum by an amount that brings the L-shell ionization potentials roughly into agreement with experiment. Our coupled-states calculations show deviations from the 1st Born approximation, and are in fair agreement with experiment. A complete comparison to experiment will require the calculation of the charge transfer channel contribution to the vacancy production.
Series of homologous displacers for preparative chiral displacement chromatographic separations on Cyclobond-II columns

Abstract A series of homologous displacers have been synthesized to aid the development of chiral displacement chromatographic separations on Cyclobond-II cyclodextrin silica stationary phases. The displacers contain an anchor group, derived from mandelic acid, a H-bonding mid-section (carboxyl and CO groups) and a solubility adjusting tail section (n-alkanoate groups). The capacity factors and the individual excess adsorption isotherms of these displacers were measured in acetonitrile-citrate buffer eluents. Both the k′ values and the isotherm parameters vary regularly with both the acetonitrile concentration of the eluent and the length of the alkanoate chain. Because the capacity factors and the adsorption strengths of these compounds cover a sufficiently broad range, they can serve as displacers in a variety of displacement chromatographic separations on Cyclobond-II columns.
Deuterium and fluorine spin-lattice relaxation in liquid CDF3

Abstract Deuterium and fluorine spin-lattice relaxation times have been measured in liquid CDF3 as a function of temperature from 112 to 188 K. The fluorine relaxation is determined by dipole-dipole and spin-rotational interactions, and the fluorine results for CDF3 are in approximate agreement with previous results obtained for CHF3. Correlation times for molecular reorientation for CDF3 are obtained from the deuteron relaxation times and are compared with correlation times obtained previously for CHF3 to show that molecular reorientation in fluoroform in nearly isotropic.
A new formulation for coherent backscattering from distributed targets

A new formulation for backscattering from distributed targets has been developed that expresses the backscattered signal received by the radar as a weighted coherent sum involving the antenna spatial spectrum and the backscattered radiation. While the general formulation is applicable to scatterers in the antenna Fresnel zone, the specific focus in this study was on the far field region.
LYSOLECITHIN AND SPHINGOSINEPHOSPHORYL-CHOLINE IN THE METABOLISM OF BRAIN PHOSPHOLIPIDS OF THE RHESUS MONKEY (MACAC A MULATTA): EFFECTS OF DEVELOPMENT

The rates of incorporation of palmitate from palmitoyl CoA into lecithin or sphingomyelin by homogenates of neural tissue of rhesus monkeys were greatly increased by the addition of lysolecithin or sphingosinephosphorylcholine (SPC). Labelled lysolecithin and SPC were also incorporated into lecithin and sphingomyelin. There was a low level of nonenzymic sphingomyelin formation from SPC and palmitoyl CoA. Choline from CDP-choline was rapidly incorporated into lecithin and slowly into SPC and sphingomyelin by homogenates of pons. The activity of lysolecithin acyl hydrolase (EC 3.1.1.5) was high throughout life in homogenates of pons and cerebral cortex. The rate of utilization of palmitoyl CoA and lysolecithin for phospholipid synthesis was higher in neural tissue from fetal and neonatal monkeys than from adults. Lysolecithin was acylated most rapidly with palmitoleic, linoleic and arachidonic acids. All phospholipid metabolic activities were higher in the cerebral cortex than in the pons.
Low authority-threshold control for large flexible structures

An improved active control strategy for the vibration control of large flexible structures is presented. A minimum force, low authority-threshold controller is developed to bring a system with or without known external disturbances back into an 'allowable' state manifold over a finite time interval. The concept of a constrained, or allowable feedback form of the controller is introduced that reflects practical hardware implementation concerns. The robustness properties of the control strategy are then assessed. Finally, examples are presented which highlight the key points made within the paper.
The University's Role In Educational Computing

For colleges and schools of education to avoid meeting the same fate as the dinosaur, says this writer, cognitive and skill development must keep pace with the widespread awareness of the computer's effect on _______ education.
Task interdependence, temporal phase, and cognitive heterogeneity as determinants of leadership behavior and behavior-performance relations

Abstract Three situational variables, task interdependence, temporal phase, and cognitive heterogeneity were hypothesized to affect the occurrence of leadership behavior and to moderate the relation between leadership behavior and performance. Results from a laboratory study of problem solving in four-person groups indicated that leadership behaviors which promote coordination were more frequent and were more highly correlated with performance on tasks with high interdependence. Phase related changes in the amount and the instrumentality of behavior were generally nonsignificant. The cognitive heterogeneity of group members bore an inconsistent relation to behavior and performance. Heterogeneity on a reflective/active dimension was negatively related to amount of leadership behavior and to performance; whereas heterogeneity on an abstract/concrete dimension was positively related to behavior and performance. Both dimensions exhibited significant moderating effects on the relation of one behavior (developing orientation) to performance.
Glycosaminoglycan stimulation of calcium release from mouse calvariae. Specificity for hyaluronic acid and dermatan sulfate.

Heparin in combination with suboptimal concentrations of parathyroid hormone (PTH) has been shown to stimulate calcium release from bone organ cultures. The mechanism of action of heparin, however, is not known. One possible mechanism relates to the highly sulfated structure of heparin. We have compared heparin to other glycosaminoglycans to stimulate calcium release from mouse calvarial organ cultures in the presence and absence of suboptimal concentrations of parathyroid hormone. The exogenous addition of heparin to bone cultures demonstrated only slight effects on calcium release at 5.0, 10, and 100 μg/ml. The addition of hyaluronic acid to the calvarial cultures caused a significant release of calcium at 10 and 100 μg/ml compared to 5 μg/ml hyaluronic acid. Dermatan sulfate was equally as effective as hyaluronic acid at 100 μg/ml but not at 10 μg/ml. A comparison of heparin- and hyaluronic acid-stimulated release demonstrated a significantly greater amount of calcium release with hyaluronic acid 100 μg/ml. At 5.0 and 10 μg/ml, there was no difference between heparin and hyaluronic acid in the amount of calcium released into the culture medium. When heparin was added to the organ cultures with suboptimal concentrations of PTH, there was a significant enhancement of calcium release observed with 10 and 100 μg/ml heparin compared to heparin addition alone. When hyaluronic acid was added with suboptimal concentrations of PTH, no significant enhancement of calcium release was observed with 100 μg/ml hyaluronic acid. Dermatan sulfate, chondroitin sulfates A and C, and keratan sulfate, in combination with PTH, stimulated significant calcium release compared to the glycosaminoglycan added alone. These results indicate that heparin is not a specific glycosaminoglycan stimulator of calcium release from mouse organ culture and that other glycosaminoglycans are more effective both alone and in combination with PTH.
Thermally activated hopping of a single Abrikosov vortex.

Thermally activated hopping of a single Abrikosov vortex has been investigated for a thin Pb film that was decorated with an artificial pinning structure. To determine the location of the vortex, the Pb film is fabricated to be one electrode of a cross-strip superconductor/normal-metal/insulator/superconductor (SNIS[prime]) Josephson junction. Distortions in the Fraunhofer pattern specify the vortex location. As the temperature is raised toward [ital T][sub [ital c]], the vortex depins from the artificial pinning site and reproducibly moves through the same sequence of other pinning sites before it leaves the junction area of the Pb film. The first thermal depinning occurs when the order parameter of the bulk superconductor is about 20% of the [ital T]=0 value. The trajectory is not random.
The effect of mutation on the intracellular location of β-glucuronidase

Abstract The intracellular distribution and some of the properties of β-glucuronidase were compared in a wild type mouse strain (DBA/2) and a strain (C3H/Ha) which carries a single gene mutation resulting in a relative deficiency of the enzyme. In the two strains the enzyme was situated in both the lysosomes and microsomes. The lysosomal enzyme was solubilized upon osmotic shock, that of the microsomes was not. The relative amounts of enzyme at the two sites were different in the two strains. This shift in the intracellular location of the enzyme is controlled by a genetic factor which is either closely linked to or identical with the gene which determines the structure and activity of the enzyme. Other enzymes present in the same particle fractions were not affected by the mutation. The glucuronidase present in the mutants is more sensitive than that of the wild type to inactivation by heat and alkali, indicating that mutants produce an enzyme of altered structure. When the activities derived from the lysosomes and microsomes of a given strain were compared, no differences in the susceptibility to heat denaturation, and pH or substrate dependence, were found. It is concluded that the changes in structure and relative concentration of the enzyme which result from the mutation are reflected in changes in the structure of the cytoplasmic particles carrying the enzyme. This would arise most simply if the changes in particle structure were secondary consequences of the alteration in the structure of the enzyme protein.
New ways to make old walls: bacterial surprises.

Two papers in this issue of Cell (Paradis-Bleau et al., 2010 and Typas et al., 2010) report that the lipoproteins LpoA and LpoB are required for the synthesis of cell walls in Escherichia coli. Attached to the bacterial outer membrane, these new cell wall components regulate penicillin-binding proteins located at the inner membrane.
Writing Against the Grain: Cultural politics of difference in the work of Alice Walker

L'A. propose, dans le cadre d'une redefinition des projets critiques en anthropologie, de ne pas releguer les travaux des femmes, notamment des femmes de couleurs, a la peripherie comme le suggere la conception postmoderniste. Les oeuvres fictives, telle celle d'Alice Walker, « The Temple of my Familiar », sont a prendre en consideration car elles donnent des enseignements ethnographiques interessants.
Multiple effects of a martensitic transition in alpha-phase uranium: Valence fluctuations, CDWS, discommensurations and solitons?

Abstract 1. 1. The D2h Pmnm space group recently reported for α'-phase U suggests the phase is that of a 2H close-packed layered structure (commensurate) resulting from a martensitic transformation. A 9R type of layering may also be possible under some circumstances. 2. 2. A model of Nagasawa (4), which explains the role of lattice softening in the matrix phase of the SME alloy agCd to give a distorted D2h13 Pmnm structure, is used to explain the probable mechanics of a martensitic α to α' phase transition in uranium. The importance of the orthorhombic structure is stressed. 3. 3. It is suggested that the Nagasawa model (4) is also relevant in explaining the appearance of valence fluctuation, CDWs, discommensuration, incommensurate and commensurate structures, SMEs and even solitons in the course of the martensitic α-U → α'-U transition 4. 4. The variability in the low-temperature physical property behavior of α-phase U is stressed. Sme experiments indicate that the room temperature orthorhombic structure is unchanged on cooling towards zero K. The above discussion may thus only be for the special case of a martensitic transformation. It is speculated that the tie-in between a martensitic transformation and valence fluctuations may be quite general. Valence instabilities may appear in other actinide systems showing lattice softening near a phase transformation, as well as in rare-earth meetallic alloys.
Modeling Solvent Effects on Electronic Excited States

The effects of solvents on electronic spectra can be treated efficiently by combining an accurate quantum mechanical (QM) method for the solute with an efficient and accurate method for the solvent molecules. One of the most sophisticated approaches for treating solvent effects is the effective fragment potential (EFP) method. The EFP method has been interfaced with several QM methods, including configuration interaction, time-dependent density functional theory, multiconfigurational methods, and equations-of-motion coupled cluster methods. These combined QM–EFP methods provide a range of efficient and accurate methods for studying the impact of solvents on electronic excited states. An energy decomposition analysis in terms of physically meaningful components is presented in order to analyze these solvent effects. Several factors that must be considered when one investigates solvent effects on electronic spectra are discussed, and several examples are presented.
Suspension of belief and epistemologies of science

Epistemological disputes in the philosophy of science often focus on the question of how restrained or expansive one should be in interpreting our best scientific theories and models. For example, some empiricist philosophers countenance only belief in their observable content, while realists of different sorts extend belief (in incompatible ways, reflecting their different versions of realism) to strictly unobservable entities, structures, events, and processes. I analyze these disputes in terms of differences regarding where to draw a line between domains in which one has warrant for belief and those in which one should suspend belief and thus remain sceptical. I consider and defend the idea that the precise location of this line is subject to a form of epistemic voluntarism, and argue that a Pyrrhonian reading of the basis of such voluntaristic choice is both natural and transformative of our understanding of these debates.
Galacto‐oligosaccharide production from lactose by Sirobasidium magnum CBS6803

N. ONISHI, I. KIRA AND K. YOKOZEKI. 1996. Galacto-oligosaccharide (Gal-OS) was produced from lactose by a yeast, Sirobasidium magnum CBS6803. With toluene-treated resting cells, 136 mg ml−1 of Gal-OS was produced from 360 mg ml−1 of lactose at 50°C for 42 h. Then, the yield of Gal-OS was increased by a culture method in which cell growth followed the enzymatic reaction : 224 mg ml−1 of Gal-OS was produced at 30°C for 60 h. Finally, combination of the toluene-treated resting cells and glucose oxidase plus catalase was applied to improve productivity by the removal of a by-product, glucose, which inhibits the Gal-OS production, from the reaction mixture. In this case, 242 mg ml−1 4-galactosyl-lactose. of Gal-OS was produced at 50°C for 42 h without cell growth. The structure of the major product ws identified as 4-galactosyl-laetos.
Elastic Scattering of Protons by Single Isotopes

Differential cross sections for the elastic scattering of 22.2-Mev protons were measured for 20 targets of predominantly single isotopic composition at \ensuremath{\sim}2\textonehalf{}-deg intervals over the angular range of 20\ifmmode^\circ\else\textdegree\fi{}-150\ifmmode^\circ\else\textdegree\fi{}. The targets ranged from ${\mathrm{Mg}}^{24}$ to ${\mathrm{U}}^{238}$ and included three pairs of isobars. Cross sections for elastic scattering of 16.4- and 9.5-Mev protons were also measured for ${\mathrm{Ni}}^{64}$ and ${\mathrm{Zn}}^{64}$ at \ensuremath{\sim}2\textonehalf{}-deg intervals over the angular range of 25\ifmmode^\circ\else\textdegree\fi{}-120\ifmmode^\circ\else\textdegree\fi{}. The 9.5-Mev data for ${\mathrm{Ni}}^{64}$ and ${\mathrm{Zn}}^{64}$ show differences in the positions of maxima and minima of the elastic scattering angular distributions that are consistent with a dependence of real nuclear potential well depth on the nuclear symmetry parameter $\frac{(N\ensuremath{-}Z)}{A}$. The 22.2-Mev data indicate that the positions of minima and maxima of the elastic scattering angular distributions are not appreciably influenced by closed nucleon shells nor by variation of $\frac{(N\ensuremath{-}Z)}{A}$. The 22.4-Mev data indicate that elastic scattering at large angles is influenced by nuclear deformation.
Theoretical and Experimental Evaluation of the Bond Strength Under Peeling Loads

Reliable applications of adhesively bonded joints require understanding of the stress distribution along the bond-line and the stresses that are responsible for the joint failure. To properly evaluate factors affecting peel strength, effects of defects such as voids on the stress distribution in the overlap region must be understood. In this work, the peel stress distribution in a single lap joint is derived using a strength of materials approach. The bonded joint is modeled as Euler-Bernoulli beams, bonded together with an adhesive. which is modeled as an elastic foundation which can resist both peel and shear stresses. It is found that for certain adhesive and adherend geometries and properties, a central void with the size up to 50 percent of the overlap length has negligible effect on the peak peel and shear stresses. To verify the solutions obtained from the model, the problem is solved again by using the finite element method and by treating the adherends and the adhesive as elastic materials. It is found that the model used in the analysis not only predicts the correct trend for the peel stress distribution but also gives rather surprisingly close results to that of the finite element analysis. It is also found that both shear and peel stresses can be responsible for the joint performance and when a void is introduced, both of these stresses can contribute to the joint failure as the void size increases. Acoustic emission (AE) activities of aluminum-adhesive-aluminum specimens with different void sizes were monitored. The AE ringdown counts and energy were very sensitive and decreased significantly with the void size. It was observed that the AE events were shifting towards the edge of the overlap where the maximum peeling and shearing stresses were occurring as the void size increased.
A hydroxylapatite batch assay for quantitation of cellular DNA damage

Abstract A batch elution procedure is described for quantitative measurement of DNA damage. The technique is based on alkaline unwinding of cellular DNA and separation of singlestranded from duplex forms by step elution from hydroxylapatite with phosphate formamide. The method is rapid, permits large numbers of samples to be handled simultaneously, and consistently yields recoveries of >95% of total chromatographed DNA. Because as many as 1 × 10 7 cells per batch may be analyzed, quantitation of the eluted DNA by nonradioactive methods is feasible. The method is standardized with respect to the unwinding constant β, the alkaline DNA unwinding unit Mng, and the DNA-damaging efficiency of ionizing irradiation.
Vasodilator Action of Angiotensin-(1-7) on Isolated Rabbit Afferent Arterioles

Recent studies have shown that angiotensin-(1-7) (Ang-[1-7]), which is generated endogenously from both Ang I and II, is a bioactive component of the renin-angiotensin system and may play an important role in the regulation of blood pressure. However, little is known about its role in regulating the reactivity of the afferent arteriole or the mechanism(s) involved. We hypothesized that Ang-(1-7), acting on specific receptors, participates in the control of afferent arteriole tone. We first examined the direct effect of Ang-(1-7) on rabbit afferent arterioles microperfused in vitro, and we tested whether endothelium-derived relaxing factor/NO and cyclooxygenase products are involved in its actions. To assess the vasodilator effect of Ang-(1-7), afferent arterioles were preconstricted with norepinephrine, and increasing concentrations of Ang-(1-7) were added to the lumen. We found that 10(-10) to 10(-6) mol/L Ang-(1-7) produced dose-dependent vasodilatation, increasing luminal diameter from 8.9+/-1.0 to 16.3+/-1.1 microm (P<0.006). Indomethacin had no effect on Ang-(1-7)-induced dilatation. N(G)-nitro-L-arginine methyl ester, a NO synthesis inhibitor, abolished the dilatation induced by Ang-(1-7). We attempted to determine which angiotensin receptor subtype is involved in this process. We found that 10(-6) mol/L [d-Ala7]-Ang-(1-7), a potent and selective Ang-(1-7) antagonist, abolished the dilatation induced by Ang-(1-7). An angiotensin II type 1 receptor antagonist (L158809) and an angiotensin II type 2 receptor antagonist (PD 123319) at 10(-6) mol/L had no effect on Ang-(1-7)-induced dilatation. Our results show that Ang-(1-7) causes afferent arteriole dilatation. This effect may be due to production of NO, but not the action of cyclooxygenase products. Ang-(1-7) has a receptor-mediated vasodilator effect on the rabbit afferent arteriole. This effect may be mediated by Ang-(1-7) receptors, because angiotensin type 1 and type 2 receptor antagonists could not block Ang-(1-7)-induced dilatation. Thus, our data suggest that Ang-(1-7)opposes the action of Ang II and plays an important role in the regulation of renal hemodynamics.
Genetic characterization of a prm− mutant of bacteriophage λ

Abstract It has been hypothesized ( Reichardt and Kaiser, 1971 ) that transcription of the λ genes c I and rex , which code for repressor and rex protein, respectively, can be initiated at either of two sites depending on whether or not repressor itself is present. On infection of a sensitive cell, transcription of repressor ( c I) and rex mRNA is thought to be initiated at a “promoter for establishment of repressor synthesis” ( pre ); however, in an established lysogen, in the presence of active repressor, synthesis of c I- rex mRNA appears to be initiated at a “promoter for maintenance of repressor synthesis” ( prm ), whose existence has been inferred from several indirect observations ( Bode and Kaiser, 1965 ; Reichardt and Kaiser, 1971 ; Echols and Green, 1971 ; Castelazzi et al. , 1972 ). In this communication, we describe the isolation of a mutant defective in prm , the promoter for synthesis of c I- rex mRNA in the presence of repressor (as in an established lysogen). The mutant, prm 116, maps at a single site between the c I gene and 0 R (the operator to which repressor binds to block rightward transcription of the λ x operon), is phenotypically c I − rex − , and yet complements the pre − mutant c Y42 for lysogenization. Thus, its existence precisely locates prm and provides a direct verification of some elements of the two-promoter hypothesis for c I- rex transcription. Since prm 116 does not appear to affect repressor binding at 0 R , the two sites, prm and 0 R , can be separated functionally by mutation.
A suggested modification in job satisfaction surveys

Summary In this paper it initially is pointed out that varying types of questions included within job satisfaction surveys often are interpreted as being equivalent; that is, as giving some measure of satisfaction-dissatisfaction. A modification is proposed which not only would overcome that difficulty, but would give some insight into reasons behind evaluations. A questionnaire incorporating this modification, and used in a survey of union member attitudes about their union organization, is described. The following conclusions were derived: (1) The danger of interpreting varying types of questions as providing a measure of satisfaction-dissatisfaction was demonstrated. (2) The proposed modification provided insight into the reasons behind satisfaction-dissatisfaction. (3) Differing statistical treatment of the data produced no significant differences in interpretation.
Morphine effects on gentamicin disposition and toxicity in mice

Morphine has been shown to reduce renal and hepatic clearance of several xenobiotics in rodents. After iv administration of gentamicin, 10 to 30 mg/kg, its plasma levels were elevated in mice given morphine, 20 mg/kg sc. Plasma clearance of gentamicin was nearly halved by morphine, due primarily to lowering of the elimination constant of gentamicin from 0.03 to 0.02 min−1 (p < 0.01). Morphine also significantly reduced urine levels of gentamicin and urine volume. In mice given naloxone, 2 mg/kg sc, morphine did not significantly raise plasma levels of gentamicin nor reduce its elimination into urine. Mice were made tolerant by morphine administration for 9 days at ascending doses to 100 mg/kg twice daily. An acute challenge with morphine, 20 mg/kg, was less effective in raising plasma levels of gentamicin or lowering its urinary elimination in tolerant mice than after chronic saline treatment. Partial tolerance to acutely administered morphine and reversal of morphine effects by naloxone suggest opioid receptor-mediated reduction of glomerular filtration by morphine in mice. Despite marked elevation of plasma gentamicin levels in morphine-treated mice, narcotic administration did not significantly increase the acute toxicity of a single dose of genatamicin. LD50 of acutely administered iv gentamicin was 51.6 mg/kg after saline and 45.3 mg/kg after treatment with morphine, 20 mg/kg sc. However, this dose of morphine enhanced the lethality of intravenously infused gentamicin. Morphine administration significantly reduced the dose of infused gentamicin needed to achieve the critical lethal plasma level.
Mapping Students' Lives: Children's Geographies, Teaching and Learning.

Abstract The relatively new field of children's geographies builds on the theoretical foundations of human geography, critical geography, and spatial theories to examine the places and spaces children inhabit and create. This article reviews four major themes in children's geographies relevant to education: exclusion and agency, the social construction of childhood, children's geographies across the globe, and children's spaces beyond the classroom. Children's geographies' unique perspective on the spatial experiences of young people offers new ways to understand issues in education theory, pedagogy, and practice.
Model-based development of four-dimensional wall motion measures

Engineers and cardiologists have taken divergent approaches to analysis of regional heart function. Our group is interested in developing clinically useful quantitative measures of endocardial wall motion, which is routinely assessed qualitatively by cardiologists using ultrasound images of the heart. We begin by parameterizing the motion of the endocardial surface in space and time, and then seek to derive quantitative measures for specific clinical applications. We illustrate here a model-based approach to designing wall motion measures using published finite element models of altered cardiac activation to screen wall-motion-based measures of synchrony of contraction. We illustrate the utility of the model in screening out measures that were initially expected to be useful, developing new measures that were not previously considered, and identifying potential limitations of these new measures to be verified experimentally in the next step of this process. Our results indicate that early systolic events and specifically early systolic rates of endocardial motion are likely the best wall-motion-based indicators of synchrony of contraction, confirming that fully four-dimensional wall motion analysis will be essential for this clinical application.
The utility of serum leptin and follicular fluid leptin, estradiol, and progesterone levels during an in vitro fertilization cycle

Purpose: To prospectively evaluate serum and follicular fluid leptin, estradiol, and progesterone levels during in vitro fertilization.
Elicited imitation in lexical development: evidence from a study of temporal reference.

This study examined the use of elicited imitation in investigating lexical development within a semantic domain. For this purpose the acquisition of reference to sequence and simultaneity by 3–5 year old children was examined. Three factors were proposed to account for the order in which lexical items within a semantic field are acquired: restrictedness of a lexical item, congruence with perceptual strategies, and conceptual simplicity. A significantly greater number of correct responses was found in sentences describing sequential events than in simultaneous events. Furthermore, imitations of sentences referring to simultaneity were more degraded than imitations of sentences referring to sequence. The children seemed to begin acquiring reference to temporally related events by learning about words describing serially ordered events. A three stage developmental model is proposed to account for the results.
Gamification of the laboratory experience to encourage student engagement.

The American Society for Microbiology (ASM) Task Force on Curriculum Guidelines for Undergraduate Microbiology Students published recommendations for introductory microbiology courses that suggest teaching specific skill sets in the laboratory beyond just fundamental knowledge and concepts of microbiology (6); however, students can sometimes view a skills-based laboratory experience as a task list of unrelated assignments to complete for a grade. Therefore, providing explicit connections throughout the lecture and laboratory exercises is critical for a truly integrated learning experience. Several pedagogical techniques can provide a coherent framework throughout a course. For example, case-based studies can connect lecture with laboratory skills and increase student engagement by applying newly developed knowledge and skills to tackle real-world simulations (2, 3). One reason that case-based studies succeed is that they can provide intrinsic motivations and an alternate purpose for students to engage with the material. A more recent trend in pedagogy involves using game design elements to increase student engagement and motivation. Gamification is the application of game design (accruing points or badges, reaching significant levels of accomplishment, or other reward elements) in a non-game context to motivate or influence participation (1, 5). A natural extension of both of these methods is to gamify a case-based approach where a fictional scenario is presented for students to role-play as scientists using their developed skills to solve a complex problem. The typical microbiology laboratory, as described by the ASM Task Force, can easily incorporate game design elements without extensive modification of the exercises themselves. Instead, gamification involves structuring the lab in a way that gives the course a coherent and unified purpose. This ultimately allows the student to see how the principles and concepts of lecture and laboratory connect to real world situations.
Model-Based Detection of Acoustically Dense Objects in Ultrasound

Traditional methods of detection tend to under perform in the presence of the strong and variable background clutter that characterize a medical ultrasound image. In this paper, we present a novel diffusion based technique to localize acoustically dense objects in an ultrasound image. The approach is premised on the observation that the topology of noise in ultrasound images is more sensitive to diffusion than that of any such physical object (???). We show that our method when applied to the problem of fetal head detection and automatic measurement of head circumference in 59 obstetric scans compares remarkably well with manually assisted measurements. Based on fetal age estimates and their bounds specified in Standard OB Tables [6], the Gestational Age predictions from automated measurements is found to be within ± 2SD in 95% and 98% of cases when compared with manual measurements by two experts. The framework is general and can be extended to object localization in diverse applications of ultrasound imaging.
Importance–Performance Analysis of the Attributes of a Cultural Festival

The purpose of this study is to conduct an importance–performance analysis on the attributes of a cultural festival. The analysis identified 12 of 20 attributes with significant differences, with seven being importance exceeding performance. Several of the seven differences were related to the authenticity of the Italian culture at the event. In addition, principal components analysis was conducted on the importance scale and differences across demographic items examined on the three components that were identified. These differences provide festival planners with knowledge to improve their performance, close the importance–performance gap, and understand differences in motivation among attendees.
Altered in vitro adrenergic responses of dog detrusor muscle after chronic bladder outlet obstruction

Muscle strips from the bladder body and dome of normal and control dogs usually demonstrate a relaxing (beta-adrenergic) response to norepinephrine. After bladder outlet obstruction was caused by urethral constriction, all body muscle strips from 7 of 12 dogs (58 per cent) demonstrated contractile (alpha-adrenergic) responses to norepinephrine. Bladder base muscle strips continued to show alpha-adrenergic responses. Desensitization or decreased beta-adrenergic receptor activity may play a part in causing the low compliance and detrusor instability seen in patients with bladder outlet obstruction.
Tissue Culture and Maintenance of the Root-Lesion Nematode, Pratylenchus Vulnus

A mixture of callus and differentiated alfalfa tissue grown on a nutrient agar provides a favorable medium for the monoxenic culture of Pratylenchus vulnus. The nematode increases more rapidly at 25° C than at 20°, and does not increase at 30° or 35°. At 25°, high populations of P. vulnus can be obtained 2 months after inoculation of the cultures. These high populations can be maintained longer at 15° or 10° than at 5°, 20°, or 25°. Nematode-free alfalfa tissue grew well over the range 20° to 30°, poorly at 35°. P. vulnus reduced the fresh weight of alfalfa callus at 20° and 25°, the temperatures favorable for nematode reproduction.
Neuroscience and the correct level of explanation for understanding mind. An extraterrestrial roams through some neuroscience laboratories and concludes earthlings are not grasping how best to understand the mind-brain interface.

An extraterrestrial roams through some neuroscience labs and concludes earthlings are not grasping how best to understand the mind/brain interface
Finite-rank potential that reproduces the Padé approximant

If a scattering potential is of a finite rank, say $N$, the exact solution of the problem can be obtained from the Born series, if the potential strength is within the radius of convergence; the exact solution can be obtained from the analytical continuation of the formal Born series outside the radius of convergence. Beyond the first $2N$ terms of the Born series, an individual term of the Born series depends on the first $2N$ terms, and the [$\frac{N}{N}$] Pad\'e approximant and the exact solution agree with each other. The above-mentioned features of a finite-rank problem are relevant to scattering theory in general, because most scattering problems may be handled as an extension of the rank-$N$ problem, in which the rank $N$ tends to infinity. The foregoing aspects of scattering theory will be studied in depth in the present paper, and in so doing we proceed in the opposite direction. Namely, given a potential, we calculate the first $2N$ terms of the Born series for the $K$ matrix and the first $N$ terms of the Born series for the wave function. Using these data, a special rank-$N$ potential is constructed in such a way that it reproduces the [$\frac{N}{N}$] Pad\'e approximant of the $K$ matrix of the original scattering problem. One great advantage of obtaining such a rank-$N$ potential is that the wave function of the system may be approximated in the same spirit as done for the $K$ matrix; hence, we can introduce a new approximation method for dealing with an off-shell $T$ matrix. A part of the mathematical work is incomplete, but the physical aspects are thoroughly discussed.
Nonparametric Identification of First-Price Auctions WithNon-Separable Unobserved Heterogeneity

We propose a novel methodology for nonparametric identification of first-price auction models with independent private values, which allows for one-dimensional auction-specific unobserved heterogeneity, based on recent results from the econometric literature on nonclassical measurement error in Hu and Schennach (2008). Our approach can accommodate a wide variety of applications in which some location of the conditional distribution of bids (e.g. min or max of the support, mean, etc.) is increasing in the unobserved heterogeneity. This includes settings in which the econometrician fails to observe the reserve price, the cost of bidding, the number of bidders, or some factor (“quality”) with a non-linear effect on bidder values.
A segmentation method for 3D visualization of neurons imaged with a confocal laser scanning microscope

Our understanding of the world around us is based primarily on three-dimensional information because of the environment in which we live and interact. Medical or biological image information is often collected in the form of two-dimensional, serial section images. As such, it is difficult for the observer to mentally reconstruct the three dimensional features of each object. Although many image rendering software packages allow for 3D views of the serial sections, they lack the ability to segment, or isolate different objects in the data set. Segmentation is the key to creating 3D renderings of distinct objects from serial slice images, like separate pieces to a puzzle. This paper describes a segmentation method for objects recorded with serial section images. The user defines threshold levels and object labels on a single image of the data set that are subsequently used to automatically segment each object in the remaining images of the same data set, while maintaining boundaries between contacting objects. The performance of the algorithm is verified using mathematically defined shapes. It is then applied to the visual neurons of the housefly, Musca domestica . Knowledge of the fly’s visual system may lead to improved machine visions systems. This effort has provided the impetus to develop this segmentation algorithm. The described segmentation method can be applied to any high contrast serial slice data set that is well aligned and registered. The medical field alone has many applications for rapid generation of 3D segmented models from MRI and other medical imaging modalities.
Neural networks predict response biases of female túngara frogs

Artificial neural networks have become useful tools for probing the origins of perceptual biases in the absence of explicit information on underlying neuronal substrates. Preceding studies have shown that neural networks selected to recognize or discriminate simple patterns may possess emergent biases toward pattern size or symmetry—preferences often exhibited by real females—and have investigated how these biases shape signal evolution. We asked whether simple neural networks could evolve to respond to an actual mate recognition signal, the call of the tungara frog, Physalaemus pustulosus . We found that not only were networks capable of recognizing the call of the tungara frog, but that they made remarkably accurate quantitative predictions about how well females generalized to many novel calls, and that these predictions were stable over several architectures. The data suggest that the degree to which P. pustulosus females respond to a call may often be an incidental by–product of a sensory system selected simply for species recognition.
CD1-restricted T cells and resistance to polysaccharide-encapsulated bacteria.

Abstract CD1 has been distinguished from conventional antigen-presenting molecules by its ability to present mycobacterial lipoglycans. Here, Rick Fairhurst and colleagues postulate that the hydrophobic groove of CD1 binds palmitic acid, displaying diverse, covalently-attached carbohydrates to T cells. Such T cells may constitute a previously unappreciated subset that helps B cells mount an antibody response to polysaccharide antigens.
Educational Websites – Cell Biology II

These are the first in a series of educational websites covering various scientific topics. As we progress in our specialties, we tend to lose touch with areas outside our immediate field of research. However, even a general background of the topics from the discussed websites can aid many aspects of our scientific careers, from understanding articles and seminars to finding an application in our own pancreatic-disease-related research in order to continually evolve and improve. In this issue, the focus is aimed at expanding our basic knowledge of cell biology.