cssi/SciSciGPT-SciSciNet huggingface dataset:
Mongrel Gravity

It was recognized almost from the original formulation of general relativity that the theory was incomplete because it dealt only with classical, rather than quantum, matter. What must be done in order to complete the theory has been a subject of considerable debate over the last century, and here I just mention a few of the various options that have been suggested for a quantum theory of gravity. The aim of what follows is twofold. First, I address worries about the consistency and physical plausibility of hybrid theories of gravity—theories involving a classical gravitational field and quantum matter fields. Such worries are shown to be unfounded. These hybrid theories—mongrel gravity—in fact comprise the only current, actual theories of gravity that incorporate quantum matter, and they also offer legitimate promise as tools for discovering the full theory of gravity. So my second aim is to highlight these theories as providing an interesting example of scientific revolution in action. I begin to try to draw some philosophical lessons from mongrel gravity theories, but more importantly I try to convince philosophers of physics that they should pay more attention to them.
Short-Term Memory for Motor Skills in Mentally Retarded Persons: Training and Research Issues

Publisher Summary This chapter is devoted to the study of memory from the cognitive tradition, including a brief presentation of a generic and widely accepted model, followed by a brief explanation of methods used by researchers to investigate short-term memory. A brief review of short-term memory in mentally retarded persons is presented. Studies in which the mentally retarded are trained to use memory strategies are emphasized. The chapter also consists of a proposal for application of memory strategies in training as well as directions for research.
Evidence and Beliefs Used in Congressional Hearings to Influence Federal Child Welfare Policy Making

This study expands the evidence base informing policy practice through an empirical inquiry of federal child welfare policy making. To do so, the study examines the association between evidence and beliefs and determines the relationship between the political context in which policy making occurs and the types of evidence and beliefs presented during federal child welfare hearings. The study considered a random sample of 150 congressional child welfare hearings testimonies from the 10-year period covered by the 106th to the 110th sessions of the U.S. Congress (1999-2008). This research used a content analysis to examine variables related to (a) witness affiliation; (b) witness level of influence; (c) the committee to which testimony was submitted; (c) the Congress in which testimony was submitted; (e) priority of intervention type, and (f) proper distribution of authority; and (g) evidence. Logistic regressions were the primary statistical analyses used to cultivate study hypotheses. Results suggest that there were significant differences in the use of evidence based on beliefs. Results also suggest that the committee to which testimonies were submitted was a significant predictor of belief use. Furthermore, affiliation a partially significant predictor of belief use, with consumers as the only significant predictor group. On the other hand, Congress and level of influence were not significant predictors of belief use. With regard to political context and evidence use, affiliation and Congress were significant predictors. This research concludes with study limitations and implications for future research.
Measurement of proteolysis in natural waters.

Microbiological proteolysis in Lake Champlain water was measured in situ and in vitro by the spectrophotometric measurement of the rate of release of soluble color from an insoluble azure dye derivative of hide powder. Water samples sterilized by microfiltration were never proteolytic. In situ proteolysis was found to be very dependent upon water temperature (1 to 23°C). No measurable activity was observed below 4°C. The in vitro proteolysis rate at 20°C was found to be 2.3 times the rate at 15°C and 6 times the rate at 10°C. Water taken from beneath the ice-covered lake throughout the winter and tested in the laboratory at 20°C was found to show an increasing proteolytic potential during the winter months. The highest activity was obtained as the ice broke up in early spring. Microbiological proteolysis in water from Burlington Harbor was often four times that found in center lake water. In most experiments proteolysis was inhibited completely by 2 μg of Cu2+ and inhibited 67% by 0.75 μg/ml. Proteolysis was markedly stimulated by 20 to 40 μg of Casitone or Casamino Acids per ml. The predominant bacteria growing in the proteolysis flasks were species of Pseudomonas and Flavobacterium. Pure cultures of Pseudomonas required traces of Casitone, Casamino Acids, or yeast extract for proteolysis of hide powder azure, whereas those of Flavobacterium did not. The requirement could not be met by a mixture of 21 amino acids and eight vitamins.
A Model of Fishing Conflicts in Foreign Fisheries

Coastal nations can impose conditions of use on foreign fishing firms that operate in their Exclusive Economic Zone. We develop a game-theoretical model in which a fishery owner maximizes the revenue that it collects from firms that operate in its EEZ by charging them a fishing fee. We find that if the number of firms is exogenous and finite the owner is likely to select a fee that is higher than socially optimal. On the other hand, if the owner can choose the number of firms it does not place any restrictions on entry to the EEZ and selects a fee that maximizes net return.
Simultaneous Purification of Murine Mammary Tumor Virus Structural Proteins: Analysis of Antigenic Reactivities of Native gp34 by Radioimmunocompetition Assays

All the structural proteins (gp47, gp34, p27, p23, p16, and p12) of the murine mammary tumor virus (MuMTV) were simultaneously purified utilizing alkylagarose chromatography as the initial fractionation step. Least-hydrophobic MuMTV polypeptides (p23, p16) and the slightly hydrophobic p27 were separated from moderately hydrophobic proteins gp47 and p12 by passage through octylimino (C 8 )-agarose; the gp47 and p12 could be removed from the matrix by elution with ethylene glycol, whereas the most hydrophobic MuMTV protein, gp34, was eluted using nonionic detergent together with ethylene glycol. Subsequent purification steps involved ion-exchange or gel filtration chromatography. The resulting protein preparations appeared near-homogeneous on analysis by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Recoveries of MuMTV proteins, based on their approximate individual contribution to total virus protein, ranged from about 20% for gp47 to greater than 100% for the minor structural component p23, the major phosphoprotein of MuMTV. Antiserum against purified C3H MuMTV gp34, together with purified, radioiodinated gp34, was used to develop a radioimmunoassay which showed that from 13 to 14% of total MuMTV protein by weight is gp34. Using this assay system, the group-specific antigenic reactivity of gp34 was also demonstrated. When solubilized preparations of C3H, RIII, and GR MuMTV9s were used as competing antigens in gp34 radioimmunoassays with anti-C3H MuMTV serum, both group- and type-specific differences in antigenic reactivity were found. Images
Enhanced production of a single domain antibody with an engineered stabilizing extra disulfide bond

Single domain antibodies derived from the variable region of the unique heavy chain antibodies found in camelids yield high affinity and regenerable recognition elements. Adding an additional disulfide bond that bridges framework regions is a proven method to increase their melting temperature, however often at the expense of protein production. To fulfill their full potential it is essential to achieve robust protein production of these stable binding elements. In this work, we tested the hypothesis that decreasing the isoelectric point of single domain antibody extra disulfide bond mutants whose production fell due to the incorporation of the extra disulfide bond would lead to recovery of the protein yield, while maintaining the favorable melting temperature and affinity. Introduction of negative charges into a disulfide bond mutant of a single domain antibody specific for the L1 antigen of the vaccinia virus led to approximately 3.5-fold increase of protein production to 14 mg/L, while affinity and melting temperature was maintained. In addition, refolding following heat denaturation improved from 15 to 70 %. It also maintained nearly 100 % of its binding function after heating to 85 °C for an hour at 1 mg/mL. Disappointingly, the replacement of neutral or positively charged amino acids with negatively charged ones to lower the isoelectric point of two anti-toxin single domain antibodies stabilized with a second disulfide bond yielded only slight increases in protein production. Nonetheless, for one of these binders the charge change itself stabilized the structure equivalent to disulfide bond addition, thus providing an alternative route to stabilization which is not accompanied by loss in production. The ability to produce high affinity, stable single domain antibodies is critical for their utility. While the addition of a second disulfide bond is a proven method for enhancing stability of single domain antibodies, it frequently comes at the cost of reduced yields. While decreasing the isoelectric point of double disulfide mutants of single domain antibodies may improve protein production, charge addition appears to consistently improve refolding and some charge changes can also improve thermal stability, thus providing a number of benefits making the examination of such mutations worth consideration.
Two-Dimensional Confinement of Nanorods in Block Copolymer Domains

Gold nanorods (NRs) self-orient during the self-assembly of a symmetric poly(styrene-b-methyl methacrylate) (PS-b-PMMA) film. The NRs are selectively sequestered and confined in lamellar PMMA domains, which are narrower than the NR length. This confinement orients 71% of NRs within ± 5° of the lamella plane. During solvent annealing, a gradient in the concentration of NRs is observed. This route to produce alternating layers containing conducting NRs separated by dielectric domains has the potential for fabricating self-assembled nanodevices.
Statistical mechanics of thermal diffusion

Abstract Expressions of the flows of atoms A and B of a binary system in a crystal are derived as the response to the imposed gradients of temperature and chemical potentials. The formulation is done using the pair approximation of the Path Probability Method of irreversible statistical mechanics and atomic migration is assumed to be via the vacancy mechanism. The energy carried by photons (and electrons) under the temperature gradient is assumed to be independent of the atomic flux. For the case near equilibrium, linear relations are derived among the atomic fluxes, the energy flux (associated with atomic flux) and the gradients. The Onsager reciprocal relations are proved to hold among the coefficients, including those related to energy flows. The heat of transport (energy carried by a diffusing atom) and the heat conduction due to atomic flux are thus unambigously derived.
On Non-Negative Quadratic Unbiased Estimation of Variance Components

Abstract Linear combinations of variance components for which there exist unbiased, non-negative quadratic estimators are characterized. It is shown that the ‘error’ component in ANOVA models is the only single component which can be so estimated.
SOME UNRESOLVED ISSUES OF CONTROL IN CONSUMER TESTS: THE EFFECTS OF EXPECTED MONETARY REWARD AND HUNGER

Consumer test subjects were split into four groups: (1) Rewarded — told they would receive payment; (2) Unrewarded — told they would not receive payment; (3) Hungry — told not to eat before the test; and (4) Pre-fed — told to eat a meal before the test. Hedonic responses for four breaded fish samples were collected. The test design was then repeated using microwave popcorn as stimuli. Rewarded subjects and hungry subjects rated samples higher than did either the unrewarded subjects or the pre-fed subjects. The responses of both the rewarded and the hungry subjects indicated no hedonic differences between samples; but among the unrewarded and the pre-fed subjects, significant differences between samples were found. Results present a dilemma for those experimenters using acceptance ratings by consumers to guide product development. This paper discusses the issue of whether these, and other unresolved factors, need to be controlled when conducting consumer tests.
A 'potentially safer' route for puncture and injection of cornual ectopic pregnancies.

Puncture and injection (usually by methotrexate) of ectopic pregnancies are relatively new modalities of treatment. Lately, these have been applied to cornual ectopic pregnancies. We describe here a proposed transvaginal ultrasound-guided puncture route, leading the needle into the cornual ectopic pregnancy, first traversing the myometrium and approaching the gestational sac from the medial aspect. After extracting the needle, there is potentially less chance for rupture and bleeding. In six of the seven injected cornual pregnancies, this technique was used without complication. The only one punctured from the lateral aspect bled and required laparoscopic intervention. This technique may enable the wider use of this treatment modality by lowering the complication rate caused by bleeding at the puncture site. Copyright © 1996 International Society of Ultrasound in Obstetrics and Gynecology
A numerical model of ice crushing using a foam analogue

Abstract A numerical model for ice crushing has been constructed that takes into account the physical processes identified in many experimental studies. These include the presence and evolution of high-pressure and low-pressure zones, the rapid removal of ice through melting, and the transformation of relatively intact ice (high-pressure zone material) to low-pressure pulverized ice through the creation and shattering of spalls. The model produces cyclic sawtooth load events and pressure distributions that are roughly characteristic of observed ice behavior. The visual and quantitative results suggest that the physical principles incorporated in the model are correct. While still in the early stages of development, with refinements the model has potential for use in simulations of various ice/structure interaction scenarios.
Two Accessory Pathways, Dual AV Nodal Conduction, and 1:2 Ventriculoatrial Conduction in a Patient with Multiple Supraventricular Tachycardias

Multiple Supraventricular tachycardias were induced in a patient with two left posterior accessory pathways and dual afrioventricular nodal conduction. One of the accessory pathways conducts slowly and exhibits decremental conduction. A “double retrograde response” (2:1 ventriculoatrial conduction) due to simuJtaneous retrograde propagation of a single ventricular depolarization over two longitudinally dissociated pathways plays a role not only in tachycardia initiation, but in the maintenance of a unique, irregular tachycardia.
Lung function and airway inflammation in rats following exposure to combustion products of carbon-graphite/epoxy composite material: comparison to a rodent model of acute lung injury.

Pulmonary function and inflammation in the lungs of rodents exposed by inhalation to carbon/graphite/epoxy advanced composite material (ACM) combustion products were compared to that of a rodent model of acute lung injury (ALI) produced by pneumotoxic paraquat dichloride. This investigation was undertaken to determine if short-term exposure to ACM smoke induces ALI; and to determine if smoke-related responses were similar to the pathogenic mechanisms of a model of lung vascular injury. We examined the time-course for mechanical lung function, infiltration of inflammatory cells into the lung, and the expression of three inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha), macrophage inflammatory protein-2 (MIP-2) and interferon-gamma (IFN-gamma). Male Fischer-344 rats were either exposed to 26.8-29.8 g/m(3) nominal concentrations of smoke or were given i.p. injections of paraquat dichloride. Measurements were determined at 1, 2, 3, and 7 days post exposure. In the smoke-challenged rats, there were no changes in lung function indicative of ALI throughout the 7-day observation period, despite the acute lethality of the smoke atmosphere. However, the animals showed signs of pulmonary inflammation. The expression of TNF-alpha was significantly increased in the lavage fluid 1 day following exposure, which preceded the maximum leukocyte infiltration. MIP-2 levels were significantly increased in lavage fluid at days 2, 3, and 7. This followed the leukocyte infiltration. IFN-gamma was significantly increased in the lung tissue at day 7, which occurred during the resolution of the inflammatory response. The paraquat, which was also lethal to a small percentage of the animals, caused several physiologic changes characteristic of ALI, including significant decreases in lung compliance, lung volumes/capacities, distribution of ventilation, and gas exchange capacity. The expression of TNF-alpha and MIP-2 increased significantly in the lung tissue as well as in the lavage fluid. Increased MIP-2 levels also preceded the maximum neutrophil infiltration. The differences in the time-course and primary site of TNF-alpha, MIP-2, and IFN-gamma expression; and the differences in the temporal relationship between their expression and infiltration of inflammatory cells may have accounted for the differences in lung function between paraquat treated and ACM smoke exposed animals.
Defective adipose lipolysis and altered global energy metabolism in mice with adipose overexpression of the lipolytic inhibitor G0/G1 switch gene 2 (G0S2).

Biochemical and cell-based studies have identified the G0S2 (G0/G1 switch gene 2) as a selective inhibitor of the key intracellular triacylglycerol hydrolase, adipose triglyceride lipase. To better understand the physiological role of G0S2, we constructed an adipose tissue-specific G0S2 transgenic mouse model. In comparison with wild type animals, the transgenic mice exhibited a significant increase in overall fat mass and a decrease in peripheral triglyceride accumulation. Basal and adrenergically stimulated lipolysis was attenuated in adipose explants isolated from the transgenic mice. Following fasting or injection of a β3-adrenergic agonist, in vivo lipolysis and ketogenesis were decreased in G0S2 transgenic mice when compared with wild type animals. Consequently, adipose overexpression of G0S2 prevented the “switch” of energy substrate from carbohydrates to fatty acids during fasting. Moreover, G0S2 overexpression promoted accumulation of more and larger lipid droplets in brown adipocytes without impacting either mitochondrial morphology or expression of oxidative genes. This phenotypic change was accompanied by defective cold adaptation. Furthermore, feeding with a high fat diet caused a greater gain of both body weight and adiposity in the transgenic mice. The transgenic mice also displayed a decrease in fasting plasma levels of free fatty acid, triglyceride, and insulin as well as improved glucose and insulin tolerance. Cumulatively, these results indicate that fat-specific G0S2 overexpression uncouples adiposity from insulin sensitivity and overall metabolic health through inhibiting adipose lipolysis and decreasing circulating fatty acids.
Gender and Anxiety: A Comparison of Student Anxiety Levels in Face-to-Face and Video Conferencing Courses

This research focuses on the role of gender in face-to-face instruction and video conferencing instruction on students’ levels of anxiety. This is due, in part, to the fact that gender and anxiety levels of students enrolled in remote video conferencing learning environments has received little attention in either psychological or educational research. A difference in gender as it relates to education is an important focus of research. This is due to the increasing learning opportunities for female students (online in particular). Explored later, further research should investigate various demographics and delivery options for courses.
Image reconstruction from compressive samples via a max-product EM algorithm

We propose a Bayesian expectation-maximization (EM) algorithm for reconstructing structured approximately sparse signals via belief propagation. The measurements follow an underdetermined linear model where the regression-coefficient vector is the sum of an unknown approximately sparse signal and a zero-mean white Gaussian noise with an unknown variance. The signal is composed of large- and small-magnitude components identified by binary state variables whose probabilistic dependence structure is described by a hidden Markov tree (HMT). Gaussian priors are assigned to the signal coefficients given their state variables and the Jeffreys’ noninformative prior is assigned to the noise variance. Our signal reconstruction scheme is based on an EM iteration that aims at maximizing the posterior distribution of the signal and its state variables given the noise variance. We employ a max-product algorithm to implement the maximization (M) step of our EM iteration. The noise variance is a regularization parameter that controls signal sparsity. We select the noise variance so that the corresponding estimated signal and state variables (obtained upon convergence of the EM iteration) have the largest marginal posterior distribution. Our numerical examples show that the proposed algorithm achieves better reconstruction performance compared with the state-of-the-art methods.
Equilibrium and kinetic aspects of brittle fracture

The lattice statics method for simulating a brittle crack will be employed to determine: (1) the energy-based criterion for crack stability, (2) at a given stress intensity in the stable region, the kinetic barrier for crack motion, and (3) the assumptions that break down in the Griffith theory when generalized to the lattice model. A simple model is used in the analysis, but this model is general enough to provide a conceptual framework for more realistic models.
Value of parasagittal magnetic resonance images in visualizing the vascular territories of the cerebellum.

Abstract The outcomes of infarctions of the cerebellar arteries may range from self-limited neuro-ophthalmic symptoms to sudden death. Identification of the affected territory may assist in clinical management because the vascular syndromes, as well as vascular mechanisms of cerebellar infarcts, are different according to the involved cerebellar arteries. However, it is usually difficult to tell the exact vascular territories using only transaxial imagings. Magnetic resonance imaging is a good tool for obtaining parasagittal and coronal images of the cerebellum, which are better for showing the vascular territories. To illustrate this point we report a 61-year-old woman with bilateral cerebellar infarcts (right posterior inferior cerebellar artery and left superior cerebellar artery who had vertigo, vomiting, headache, intermittent vertical diplopia, and difficulty walking. The clinical value of parasagittal imaging of the cerebellum in this case is discussed.
Special session — Mixed methods in engineering education: Developing research questions and mixing tables

The aim of this special session is to re-introduce the concept of “mixing” as a part of a mixed methods study design. Engineering education researchers are increasingly choosing mixed methods for their study designs, but may not be obtaining the full benefit from their use. In order to highlight specific aspects of the definition of mixed methods research, groups will establish a qualitative, quantitative and “mixing” research questions using the topic of Engineering Student Retention. Through collaborative development of the mixing research question, participants will be exposed to various ways to integrate qualitative and quantitative data. After discussing the combinations of qualitative, quantitative and mixing research questions in the large group, participant teams will sketch out possible mixing tables that integrate their qualitative and quantitative data. Creation of the mixing tables will further explore the integration possibilities, allowing participants to explore ways to maximize the potential of their data. This session is highly collaborative and encourages participation from researchers from all backgrounds (qualitative, quantitative and mixed methods) and experience levels.
An effective method for improving the fertility of glycerol-exposed poultry semen

Semen cryopreservation is necessary for banking germplasm from critical poultry stocks. To date, glycerol is the most effective cryoprotectant for poultry sperm; however, the contraceptive effects of glycerol require a significant reduction of the cryoprotectant from thawed semen before artificial insemination (AI). The effectiveness of glycerol reduction by dialysis, Percoll density gradient centrifugation, or washing through 12% (wt/vol) Accudenz was evaluated by fertility trials with highly inbred chicken research lines and commercial turkey lines. Semen was extended 1:1 and then diluted with glycerolized extender to yield a final 11% (vol/vol) glycerol concentration. Glycerolized rooster semen was aliquoted for control, Accudenz centrifugation, and dialysis treatments. A total of 90 pure line and 85 F1 hybrid chicken hens were each inseminated with 100 x 10(6) sperm at 7-d intervals for 4 to 6 wk. All eggs from the glycerolized control semen treatments were infertile, and fertility rates from dialyzed semen decreased steadily from 26.4 to 0% within the first 4 wk for the pure lines. In contrast, fertility rates for Accudenz-processed semen increased from 17.9 to 37.17% during the first 4 wk. Similar fertility rates occurred with the F1 hybrid cross lines. For turkey fertility trials, the dialysis treatment was not used; glycerolized turkey semen was processed by Accudenz or Percoll centrifugation to reduce glycerol. A total of 36 hens were inseminated with 150 x 10(6) sperm at 7-d intervals for 6 wk. Similar to the chicken trials, fertility rates of Accudenz-processed semen steadily increased to 49.4% by the sixth week of insemination. The average fertility of Percoll-processed semen was only 19.1%. These data demonstrate that Accudenz centrifugation is an acceptable glycerol reduction method for nonfrozen poultry semen.
Look Again: The Multiples of Photographic Discernment and Production

AbstractThis essay explores the task of visual discernment as both a recreation and a prerequisite for productivity in the modern economy in Britain in the 1860s. The investigation is anchored by the close analysis of two exemplars of the second generation of British photography, O. G. Rejlander and his student and sometime rival Henry Peach Robinson, whose photographs evince a complex repertoire which engages the viewer's ability to discern the mode of their constructedness, cultivating a game of visual discrimination with a series of coherent and consistent pictorial clues. Indeed, one might say that Rejlander and Robinson's central project was interrogating the dubious claims of photographic neutrality. This dubiousness was the basis through which the two photographers elaborated an iconography that made the process of discerning the specific modalities of their intervention the basis of their production. They fashioned a body of work that harnessed the kind of visual acuity developed for educational a...
Electric shock—Safety factors when used for the aversive conditioning of humans

Electric shock is used as an aversive stimulus in the treatment of a great variety of behavioral problems. In spite of the extensive use of shock, no easily accessible and assimable source of information on its safe application is available to behavior therapists. This article discusses electrical shock, electrical shock equipment, and considerations involved in its use.
A Pilot Use of Team-Based Learning in Psychiatry Resident Psychodynamic Psychotherapy Education.

Objective Demonstrating psychotherapy competency in trainees will test the resources of psychiatry training programs. The authors outline the phases of team-based learning (TBL).
Programmed Transformations in Neuroblast Gene Expression during Drosophila CNS Lineage Development

During Drosophila embryonic CNS development, the sequential neuroblast (NB) expression of four proteins, Hunchback (Hb), Pou-homeodomain proteins 1 and 2 (referred to collectively as Pdm), and Castor (Cas), identifies a transcription factor network regulating the temporal development of all ganglia. The Zn-finger proteins Hb and Cas, acting as repressors, confine Pdm expression to a narrow intermediate temporal window; this results in the generation of three panneural domains whose cellular constituents are marked by expression of Hb, Pdm, or Cas (R. Kambadur et al., 1998, Genes Dev. 12, 246–260). Seeking to identify the cellular mechanisms that generate these expression compartments, we studied the lineage development of isolated NBs in culture. We found that the Hb, Pdm, and Cas expression domains are generated by transitions in NB gene expression that are followed by gene product perdurance within sequentially produced sublineages. Our results also indicate that following Cas expression, many CNS NBs continue their asymmetric divisions generating additional progeny, which can be identified by the expression of the bHLH transcription factor Grainyhead (Gh). Gh appears to be a terminal embryonic CNS lineage marker. Taken together, these studies indicate that once NBs initiate lineage development, no additional signaling between NBs and the neuroectoderm and/or mesoderm is required to trigger the temporal progression of Hb → Pdm → Cas → Gh expression during NB outgrowth.
Axon guidance: A balance of signals sets axons on the right track

Axon guidance depends on the transduction of extracellular guidance cues into motile responses by the axonal growth cone. Recent studies in vivo have elucidated mechanisms required for this process that involve kinases and phosphatases, calcium dynamics and remodeling of the actin cytoskeleton.
The decay of synchronization of cell division

Abstract Consider a synchronized culture in which there are n(t) cells at time t. Approximating the doubling time distribution function of the individual cells by a rectangular distribution of width 2 δ and mean T , the differential-difference equation for the increase in cell number during the period of decay of synchronization is dn dt = [n(t − T + δ) − n(t − T − δ)] δ . The corresponding integral equation for the normalized rate of cell division, R = ( dn dt )/n , is R(t)= [ exp (− ∫ t− T +δ t R(t)dt) − exp (− ∫ t− T −δ t R(t)dt)] δ By means of the first equation the standard deviation of cell doubling times can be estimated from data on the decay of synchronization of a culture when precise growth data are available. Solutions to these equations have been obtained by a digital computer. These can be used to obtain estimates of the rate of decay of synchronization when the standard deviation of cell doubling times is known.
High-pressure fluorescence line narrowing of Eu(III)-doped sodium disilicate glass.

High-pressure fluorescence line narrowing (HPFLN) has been used to characterize the local structure of ${\mathrm{Eu}}^{3+}$ ions in sodium disilicate glass up to 210 kbar. HPFLN spectra, measured at 77 K, were analyzed using crystal-field theory. As pressure was increased from ambient to approximately 40 kbar, a redshift of the $^{5}D_{0}\ensuremath{\leftarrow}^{7}F_{0}$ excitation band was accompanied by a simultaneous decrease in the ${\mathrm{Eu}}^{3+}$ site crystal-field strength and a lengthening of the fluorescence lifetime from approximately 2.3 to 2.4 ms. These trends were reversed above 40 kbar, as crystal-field strength increased with pressure and lifetime decreased linearly to approximately 1.4 ms at 210 kbar. The $^{5}D_{0}\ensuremath{\leftarrow}^{7}F_{0}$ excitation band broadened significantly above 70 kbar and continued to shift red above 150 kbar. HPFLN results are interpreted in terms of structural changes in the silicate glass matrix and compression of the ${\mathrm{Eu}}^{3+}$ bonding environment. Lifetime and intensity changes are attributed to a pressure-induced increase in the electron-phonon coupling to local vibrations. Pressure-induced crystal-field effects are used to deduce characteristics of high- and low-crystal-field-strength sites in ambient pressure glasses. Spectral and lifetime results for the sample released from high pressure show that a new local ${\mathrm{Eu}}^{3+}$ structure is formed during decompression.
Predicting stochastic features of vapor bubble detachment in flow boiling

Abstract The stochastic features of vapor bubble departure and lift-off diameters in forced convection boiling are considered in terms of probability density functions (pdfs). A mechanistic model is developed for the prediction of these functions. Their prediction requires a vapor bubble detachment model and pdfs of the mean wall superheat and mean liquid velocity. The agreement with horizontal flow boiling vapor bubble departure and lift-off data is very good. To the best of the authors' knowledge, this is the first attempt at developing such a predictive capability. In order for the model to be generally applicable to flow boiling systems, the assumptions used in estimating the mean wall superheat and mean vapor velocity pdfs require further scrutiny.
CFTR Genotype as a Predictor of Prognosis in Cystic Fibrosis

Study rationale Certain CFTR genotypes are associated with reduced mortality. The accuracy of using CFTR genotype as a predictor of survival and the mechanisms through which CFTR genotype influences survival are unknown. Participants All patients with cystic fibrosis (CF) enrolled in the US Cystic Fibrosis Foundation national registry between 1993 and 2002. Design We examined the prognostic value of CFTR genotype, grouped into "high-risk" and "low-risk" categories based on the effect of their CFTR genotype on phenotype and protein production. Measurements and results Clinical and genetic data were available from 15,651 patients with CF. Patients with a high-risk CFTR genotype had a greater than twofold increased risk of death compared to patients with a low-risk CFTR genotype (relative risk, 2.25; 95% confidence interval [CI], 1.77 to 2.84; p Conclusions Grouping patients into high-risk and low-risk CFTR genotype categories is associated with significant differences in survival and median age at death. These differences are not fully explained by lung function, nutritional measures, pancreatic insufficiency, or P aeruginosa colonization. Modest reassurance about the likelihood of a milder than average course can be provided for CF patients with a low-risk CFTR genotype, although it should be acknowledged that substantial phenotypic variability exists.
An energy-distribution strategy in fast-cutting wire EDM

Abstract The technical requirements of fast-cutting wire EDM are revealed in this paper. In addition to high input pulse energy, fast cutting (cutting speed > 200 mm 2 /min) without damaging the electrode wire needs a high energy efficiency for maintaining a stable fast-cutting process and moderate wire temperature. Based on a synthesis of experimental results and pulse energy analysis, an energy-distribution diagram concerning the correlation between cutting speed and comprehensive machining conditions has been established to determine a suitable parameter combination for a stable fast-cutting process. High power density and high pulse density are found to be two basic requirements for a constant high cutting speed. Harmful energy loss has to be reduced, otherwise the wire temperature becomes too high due to the dissipated heat. According to the energy-distribution diagram, machining conditions such as cutting width, wire diameter and wire traveling speed are also considered in increasing the cutting speed. After an optimization of the energy distribution in fast-cutting wire EDM, a 4-fold improvement in cutting speed has been achieved whilst the wire service life remains almost unchanged. The surface conditions of the cut workpiece are examined through SEM microscopy: the surface roughness is lower than usually expected. A systematic approach is presented for a very fast cutting process. The achievements described here have practical significance in enhancing mold/die productivity as well as in transferring wire EDM into a general cutting alternative. With the cutting speed being increased, the inherent advantages of wire EDM can be used in many cutting cases.
ANGULAR DISTRIBUTIONS FROM MULTIPARTICLE PRODUCTION MODELS

Using $\mathrm{exp}(\ensuremath{-}A{{p}_{T}}^{2})\frac{{d}^{3}p}{E}$ as the momentum distribution of secondaries produced in ultrahigh-energy collisions\char22{}a result predicted by the multiperipheral model, by Feynman's parton model, and by Cheng and Wu's consideration of hadrons as extended objects with many internal degrees of freedom\char22{}we obtain the characteristic features of the angular distribution. We discuss the dependence on incident energy, mass of secondaries, and the value of $A$. We find that the c.m. angular distribution on the variable ${\ensuremath{\eta}}_{\mathrm{c}.\mathrm{m}.}=\ensuremath{-}\mathrm{ln}tan\frac{1}{2}{\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}$. has a two-bump structure, whereas the lab angular distribution in $\ensuremath{\eta}=\ensuremath{-}\mathrm{ln}tan{\ensuremath{\theta}}_{l}$ is flat. This difference leads us to a discussion of the transformation between c.m. and lab angular distributions. We find that the usual relativistic approximation of the exact transformation leads to incorrect results. Finally, we point out that these momentum and angular distributions approach limiting distributions.
Thoughts on the Teaching of Metabolism

Systems biology, metabolomics, metabolic engineering, and other recent developments in biochemistry suggest that future biochemists will require a detailed familiarity with the compounds and pathways of intermediary metabolism and their biochemical control. The challenge to the biochemistry instructor is the presentation of metabolic pathways in a manner that allows student creativity in learning the pathways and their components. One approach that does permit the use of problem solving for the study of metabolic pathways involves following the fate of 13C, 14C, or 15N labels, presented originally in the structure of an important metabolic starting compound, through relevant metabolic pathways. This method allows the presentation and study of problems in which such an isotopic label can be traced through two or more metabolic pathways, thus illustrating how these pathways are interconnected. The understanding that all the pathways of intermediary metabolism are interconnected provides opportunities to discuss their metabolic control by such mechanisms as signaling, feedback inhibition, location in organelles, coenzyme levels, and coenzyme recycling rates. The method is illustrated by following the fate of 14C labels through anaerobic glycolysis, gluconeogenesis, and fatty acid transport, β-oxidation, and ketone body formation. Cholesterol biosynthesis and heme formation are used to show that presentations of long and complex pathways can demonstrate important biochemical concepts by following the fate of an isotopic label using only the most important intermediates. Problems based on tracing radioactive labels through one or more metabolic pathways allow the use of cooperative learning techniques.
Electrical Connections Letters to Thomas Edison in Response to His Claim of Solving Incandescent Lighting, 1878

When the New York Sun reported that Thomas Edison had solved the problem of incandescent lighting, that purported invention generated immense excitement across many segments of the American populat...
Ionic polymerization of vinyl halides initiated by photoionization using photons with energies near the ionization threshold

Abstract Thermal bimolecular rate coefficients have been obtained for the reactions of the parent monomer ions in the vinyl halides with the respective neutral molecules when the ions are formed by photoionization at or very near the ionization thresholds. The values obtained are as follows: C 2 H 3 F + , 0.27 eV above threshold, k = 3.2 × 10 −10 cm 3 molecule −1 s −1 , C 2 H 3 Cl + , within kT of threshold, k = 1.78 × 10 −10 cm 3 molecule −1 s −1 , and C 2 H 3 Br + , 0.2 eV above threshold, k = 1.25 × 10 −10 cm 3 molecule −1 s −1 . An increase in photon energy drastically lowers the values of these coefficients. The reactions of C 2 H 3 F + and C 2 H 3 Cl + were also investigated at high pressures in order to elucidate certain aspects of the cationic polymerization scheme. The formation of (C 2 H 3 Cl) 2 + and (C 2 H 3 Cl) 3 + is reported for the first time. The factors controlling the relative importances of various modes of dissociation of the vinyl halide dimer ions are discussed in terms of thermodynamic and structural considerations.
Disordering of Solids by Neutron Radiation

A general method is outlined for determining the number of vacant lattice sites or interstitial atoms in a monatomic solid exposed to neutron radiation. The colliding atoms are assumed to be within the energy range for which the orbital picture can be applied. Following the treatment of Bohr, the scattering regions of excessive and moderate screening, Rutherford distribution, and electronic collisions are considered separately. The number of vacancies or interstitial atoms as a function of the energy of the primary knocked-out atom is given by the solution of certain integral equations that are different for various energy regions considered. It is found that if the velocity of a recoil atom resulting from neutron collision is less than $\frac{{e}^{2}}{\ensuremath{\hbar}}$ (region of elastic collisions) approximately half of its energy is used up to produce vacancies or interstitials. If the velocity of the recoil atom is above $\frac{{e}^{2}}{\ensuremath{\hbar}}$ (region of inelastic collisions) then the energy used up to produce vacancies and interstitials is approximately constant for medium and heavy elements. A simple formula has been derived expressing the average number of vacant lattice sites or interstitials produced in a collision of a neutron having energy $E$ in a monatomic solid composed of medium or heavy elements having atomic mass $M$. The formula is as follows: $G(E)\ensuremath{\sim}\frac{{(nE\ensuremath{-}\ensuremath{\alpha})}^{2}}{4\ensuremath{\alpha}\mathrm{nE}} \mathrm{for} E\ensuremath{\leqq}\frac{\ensuremath{\gamma}}{n},$ $G(E)\ensuremath{\sim}\frac{[{(nE\ensuremath{-}\ensuremath{\alpha})}^{2}\ensuremath{-}(1\ensuremath{-}\overline{R}){(nE\ensuremath{-}\ensuremath{\alpha}\ensuremath{-}\ensuremath{\gamma})}^{2}]}{4\ensuremath{\alpha}\mathrm{nE}} \mathrm{for} E\ensuremath{\geqq}\frac{\ensuremath{\gamma}}{n},$ where $\ensuremath{\gamma}=\frac{M{e}^{4}}{2{\ensuremath{\hbar}}^{2}}$; $n=\frac{4M}{{(M+1)}^{2}}$, $\ensuremath{\alpha}$ is the binding energy of an atom in the lattice, and $\overline{R}$ is a slowly varying function of $Z$.
Validity and reliability of the Johns Hopkins Adapted Cognitive Exam for critically ill patients

Assessment of cognition in ICU patients is a critical component of evaluating cerebral dysfunction. Several cognitive tools also exist for assessment of delirium in the ICU. However, few are simple to use and none has been specifically designed to focus on cognition in ICU patients. The Johns Hopkins Adapted Cognitive Exam (ACE) is an examination tool on a 100-point scale specifically designed for the assessment and quantification of cognition in critically ill patients.
Electron-phonon coupling of G mode and assignment of a combination mode in carbon nanotubes

We measure the electron-phonon (e-ph) coupling matrix elements of the $G$ band in semiconducting carbon nanotubes (CNTs) in comparison to the radial breathing mode (RBM). The experimental result for the ${G}^{+}$ mode [\ensuremath{\Gamma}-point longitudinal optical (LO) phonon] at the ${E}_{22}$ transition suggests an e-ph coupling strength of approximately 30 meV or 12.5 eV/\AA{}, which is within the expected range of 23 meV to 83 meV for a 1-nm-diameter CNT. This coupling (as the square of the matrix elements) for the ${G}^{+}$ mode is an order of magnitude higher than that of the RBM and other measured phonon modes. In addition we assign a Raman feature observed around 1700 cm${}^{\ensuremath{-}1}$ to be the combination mode of a low energy (\ensuremath{\sim}400 cm${}^{\ensuremath{-}1}$) and a high energy (\ensuremath{\sim}1300 cm${}^{\ensuremath{-}1}$) zone-boundary phonon. Both the phonon energies and phonon dispersions of those modes support the assignment.
Preoperative marijuana inhalation — An airway concern

Cannabis Sativa (marijuana) may cause a variety of respiratory disorders including uvular oedema. This case illustrates that uvular oedema secondary to marijuana inhalation may cause a potentially serious postoperative clinical problem. A healthy 17-yr-old man who inhaled marijuana prior to general anaesthesia. In the recovery room, after an uneventful general anaesthetic, acute uvular oedema resulted in post operative airway obstruction and admission to hospital. The uvular oedema was treated successfully with dexamethasone. Recent inhalation of marijuana before general anaesthesia may cause acute uvular oedema and post operative airway obstruction. The uvular oedema can be easily diagnosed and treated.
Propagation of sound waves through a linear shear layer: A closed form solution

Closed form solutions are presented for sound propagation from a line source in or near a shear layer. The analysis was exact for all frequencies and was developed assuming a linear velocity profile in the shear layer. This assumption allowed the solution to be expressed in terms of parabolic cyclinder functions. The solution is presented for a line monopole source first embedded in the uniform flow and then in the shear layer. Solutions are also discussed for certain types of dipole and quadrupole sources. Asymptotic expansions of the exact solutions for small and large values of Strouhal number gave expressions which correspond to solutions previously obtained for these limiting cases.
Composition of Serum from Cooked‐Frozen‐Thawed‐Reheated Scrambled Eggs at Various pH Levels

The volume of serum pressed from the Cooked-Frozen-Thawed-Reheated (CFTR) scrambled egg decreased as pH was increased from 6.0 to 7.0. Solids, protein and lipid levels were maximal at pH 7.0. Ash and phosphorus contents decreased with increased pH. Sodium and potassium remained constant. Chloride concentration increased from pH 6.2 to 6.8. Iron had maximal levels at pH 6.2 and to 6.8 to 7.2. The lipid and phosphorus levels in the serum were very low when compared to those in the original liquid whole egg. Ovomacroglobulin, lipovitellin and some of the globulins and livetins were absent in the electrophoretograms of the serum. Also, a band appeared in the ovomucoid area which was not normally present in uncooked egg.