cssi/SciSciGPT-SciSciNet huggingface dataset:
Biological Noise in an Organelle Size Control System

Abstract Stochastic variations (noise) in gene expression have been extensively characterized, but the ramifications of this gene-level variation for cellular structure and function remain unclear. To what extent are cellular structures subject to noise? We show that flagellar length in Chlamydomonas exhibits significant variation that results from a combination of intrinsic fluctuations within the flagella and extrinsic cell to cell variation. We analyzed a series of candidate genes affecting flagella and found that flagellar length variation is increased in mutations which increase the average flagellar length, an effect that can be explained using a theoretical model for flagellar length regulation. Cells with greater differences in their flagellar lengths show impaired swimming but improved gliding motility, raising the possibility that cells have evolved mechanisms to tune intrinsic noise in length. Taken together our results show that biological noise exists at the level of subcellular structures, with a corresponding effect on cell function.
More Than Animals

Humans have long argued that they are higher, better, and more intelligent than other animals. This chapter argues that this is actually not true. There are unique aspects to all animals, but no clear hierarchy if we define things like intelligence in ways that do not just “rig the game” in the favor of humans. The chapter begins a discussion of the up and down sides of consciousness.
Barium ion adduct mass spectrometry to identify carboxylic acid photoproducts from crude oil–water systems under solar irradiation

Petroleum derived dissolved organic matter (DOMHC) samples were successfully cationized with barium, revealing many [M-H + Ba]+ peaks in both dark and simulated sunlight treatments. The DOMHC samples generated after light exposure exhibited a greater number of [M-H + Ba]+ peaks compared to the dark control. Multiple [M-H + Ba]+ peaks were investigated in the irradiated DOMHC using low resolution MS/MS in order to confirm the presence of diagnostic fragment ions, m/z 139, 155 and 196 in each treatment. Due to the high complexity of the bariated DOMHC mixture, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS/MS) was employed to obtain molecular level information for both irradiated and dark treatments. The irradiated DOMHC treatments had more bariated oxygenated species over a wide range of H/C and O/C when compared to the dark controls. Doubly bariated species were also observed in DOMHC, which provides evidence that photochemistry transforms DOMHC to even more complex mixtures with multiple oxygenations per molecule. This study provides evidence that barium adduct mass spectrometry can be successfully applied to DOMHC screening for the presence of COOHs, both in dark samples and solar irradiated samples. Furthermore, direct evidence and molecular composition of aqueous phase crude oil photoproducts is provided by this technique.
XMM-Newton Observations of Broad Iron Kα Emission from Seyfert 1.9 Galaxy MCG –5-23-16

XMM-Newton observations of the bright Seyfert 1.9 galaxy MCG -5-23-16 have revealed a broad Fe Kα emission line that is nearly symmetric in contrast to the broad and redshifted asymmetric Fe Kα line sometimes observed from Seyfert 1 galaxies. The Fe Kα line has two distinct components—a narrow unresolved component with an equivalent width of ~40 eV and a broad component with a FWHM of ~40,000 km s-1 and an equivalent width of ~120 eV. An absorption feature at ~7.1 keV has also been observed. The energies of the emission and absorption features are consistent with those arising from neutral iron. The broad component is consistent with a Fe Kα emission line expected from a relativistic accretion disk around a Schwarzschild or Kerr black hole. Alternatively, most of the flux in the broad component could also be modeled as reflection emission, which mimics emission line-like features because of the presence of iron K-shell edge at ~7.1 keV; however, the reflection fraction, R ~ 3, is much higher than that inferred from the BeppoSAX observations (R ~ 0.5). The disk inclination angle of ~47°, inferred from the disk-line fits, and the absorption column (NH ~ 1022 cm-2), inferred from the low-energy spectral curvature due to photoelectric absorption, suggest that our line of sight passes through the outer edge of a putative torus and are consistent with those expected for a Seyfert 1.9 galaxy falling within the unification scheme. The strength of the narrow iron Kα emission and the optical depth of the iron K absorption edge suggest their origin in the putative torus with NH ~ 1024 cm-2 in the inner regions and NH ~ 1022 cm-2 in the outer edges. The strength of the broad component of Fe Kα varied by a factor of ~2 between the two XMM-Newton observations taken ~6 months apart, while the narrow component of Fe Kα and the continuum flux did not appear to vary appreciably. There is evidence for a weakening in the strength of the broad iron Kα emission with the flattening of the observed continuum. This can perhaps be explained if the shape of the continuum is coupled with the ionization stage of the reflector.
Looking Closely at Clinical Practice: A Clear-Eyed Vision for the Future of Teacher Education

Clinical practice has long been an integral component of teacher education. In the past two decades, however, the call has intensified for more purposeful, inclusive, integrated, and reflective cli...
Reducing Conductivity Variability in Si Nanowires via Surface Passivation for Nanoelectronics

Ensembles of semiconductor nanowires grown via the bottom-up vapor–liquid–solid (VLS) mechanism, especially those that are lightly doped or nominally undoped, can exhibit large nanowire-to-nanowire...
Surgery for the Urine Pooling Cow

Before considering surgery for the urine pooler one must first understand why urine pooling is detrimental and what constitutes a diagnosis of a urine pooler. Doing surgery for a urine pooler is of no benefit if the cow has other pathology which is causing her infertility unless these other problems are treated concurrently or in place of urine pooler surgery.
Mechanical and tribological properties of self-lubricating bio-based carbon-fabric epoxy composites made using liquid composite molding

Abstract Polymer composites reinforced with fibrous materials are used in several tribological and mechanical applications. In this study, the effect of carbon fiber as a reinforcement on the mechanical and tribological properties of a bio-based epoxy composite was investigated. The level of cure was investigated using DSC and the tribo-surfaces were studied using SEM micrographs. Use of carbon fibers with epoxy composites expectedly enhanced the bending strength and modulus of the composite. More importantly, the use of carbon fibers improved the tribological properties. Taguchi technique was employed in order to extract the data in a controlled situation in the experiments. Through the regression analysis equations, it was possible to predict the COF and volume loss as a function of these parameters.
A framework for improving efficiency and accuracy

Publisher Summary This chapter reviews a framework for improving efficiency and accuracy. One of the main goals of machine learning is to improve performance, and the two most studied performance measures are efficiency and predictive accuracy. The knowledge acquired by a learning system must be efficient to use and accurate. Thus, research under such a theme aims essentially at producing a framework where both efficiency and accuracy may achieve a simultaneous incremental nature and where advances in one of the these is not occurring at the cost of the other. The framework presented in the chapter is an extension of work in explanation-based and inductive learning. Research on inductive learning has primarily focused on improving predictive accuracy. The task of learning from examples is a form of inductive learning that builds concept descriptions based upon instances labeled with their class information. Concept hierarchies are an important component of many inductive learning methods. The hierarchy is used to classify instances by beginning with the concept in question. Whenever a concept is matched, all the bindings produced by the match are stored with the concept. The matcher will do less work if it matches the concept multiple times.
The dynamics of subjectivity

I adapt the dynamic framework for vagueness of Barker 2002 to the analysis of subjective taste predicates. I argue, following Kennedy 2013, that there are two qualitatively distinct types of subjectivity in natural language, which I call mapping subjectivity and (vague) standards subjectivity, and that the matrix predicate *find* is sensitive to the distinction between them. Novel to the present analysis is the proposal that *find* requires not just a complement that supports mapping subjectivity, but also a context that supports nonvacuous entailments about those scalar mappings. I part ways from Kennedy and from Barker 2013 in treating mapping subjectivity as a fact of the world, unassimilable to the metalinguistic variety of subjectivity associated with vague standards.
TRADE EXECUTION COSTS AND THE DISINTERMEDIATION OF TRADING IN A COMPETING DEALER MARKET

The growth of alternative trading systems that compete with established stock marketswill have profound effects on many securities exchanges and their member firms. Newscreen-based markets can match buy and sell orders, and confirm trades electronically tothe participants. In many cases, investors' orders meet directly in the system without theinvolvement of a broker or a dealer, saving intermediation costs such as the bid-askspread and broker commission costs. Competing market makers operating on the LondonStock Exchange's SEAQ market system provide an intermediated, "quote-driven" tradingmechanism. Nearly all equities trading in London today occurs through SEAQ, but theapproaching roll-out of several alternative trading systems will provide investors with newopportunities to trade without market makers. A simulation model of order arrival, informationchange, and trading in a competing dealer market based on the London StockExchange is used to examine the consequences of disintermediated trading systems. Theresults indicate that trading by market makers at their discretion at "midspread" pricesleads to a significant reduction in dealing margins. In two other scenarios, the operationof an alternative, disintermediated order crossing mechanism, reduces market makers'trading volumes and lowers the level of intermediation at some savings to investors.Alternative trading systems reduce transactions costs borne by some traders, but thoserequiring immediate execution and dealer intermediation may pay more.
Mode reconstruction for source coding and multi-modal control

In this paper we take the point of view that control procedures have an information theoretic content that can be more or less effectively coded. Of particular interest are control procedures for navigation and obstacle avoidance for mobile robots, and we show how tokenized instructions can be used for understanding how computer generated inputs to robotics systems should be defined, selected, and coded. To this end, a dynamic programming algorithm is developed for generating control procedures that are useful in given robotics applications.
Increased Resistance of Pseudomonas aeruginosa to Carbenicillin After Reversion from Spheroplast to Rod Form.

Five of six strains of Pseudomonas aeruginosa had at least fourfold increase in resistance to carbenicillian after they reverted from carbenicillin-induced spheroplasts to rod forms. The most susceptible laboratory strain showed the greatest increase in resistance. There was a marked inoculum effect on the minimal inhibitory concentration of carbenicillin when high inocula (107 colony-forming units) or very low inocula (102 or 103 colony-forming units) were used. Population analysis of this reverted strain revealed increase in resistance of the entire population of cells to carbenicillin. However, the degree of resistance was not homogenous. Only a few cells were highly resistant. Comparison of the effect of carbenicillin on the growth of the parent and reverted strains confirmed the increase in resistance of the reverted strain. The resistance remained stable after 42 passages.
Effect of particle size and doses of olivine addition on carbon dioxide sequestration during anaerobic digestion of sewage sludge at ambient and mesophilic temperatures

Biogas from anaerobic digestion of sludge at wastewater treatment plants consists of methane, carbon dioxide and trace contaminants which can be upgraded for utilization. Compared to current costly upgrading technologies, mineral carbonation has many benefits by using natural magnesium and calcium rich ores capable of sequestering CO2. The feasibility of olivine to sequester CO2 in-situ during batch anaerobic digestion of sludge was tested for (1) ambient versus mesophilic temperatures, (2) placement of olivine in the digester, and (3) olivine particle size and concentration. Increasing the temperature, increasing the olivine surface area via increased dose and decreased particle size, and elevating the olivine in the reactor increased mineral carbonation rates during anaerobic digestion. At mesophilic temperature, the elevated 5% w/v fine olivine digester had a 17.5% reduction in CO2 which equated to a 3.6% increase in methane content (%) and at ambient temperature, the same condition had a 21.7% CO2 sequestration resulting in an 8.8% increase in methane content compared to the control. Response surface methodology was applied for optimization of digestion time and olivine surface area at both temperatures.
Electron spectra of a self-assembled monolayer on gold : Inverse photoemission and two-photon photoemission spectroscopy

Abstract Ultraviolet photoemission spectroscopy, inverse photoemission spectroscopy, and two-photon photoemission spectroscopy are techniques commonly used to examine the electronic structure of surfaces and interfaces. We have used all three to study self-assembled monolayers of 4,4′-bis(phenylethynyl)benzenethiol on gold, a system often studied for potential application in molecular electronic junctions. We compare the results of these measurements and discuss them in relation to electronic structure calculations. The result is a better understanding of the valence electronic structure for this system, of the spectroscopic methods involved, and of previous measurements.
On a hybrid method to characterize the mechanical behavior of thin hollow glass microspheres

Hollow glass microspheres possess niche markets and future research areas due to their high strength-to-density ratio and low thermal conductivity. For example, these qualities make them a viable alternative insulation medium. For this study, Scotchlite™ k1 hollow glass microspheres (HGMs) manufactured by 3M™ were used; however, one of the challenges in investigating their mechanical properties was due to the limited availability of published data. Most importantly, the thickness (or the range of thicknesses) of produced thin hollow microspheres is not measured by the manufacturer, so the authors needed to develop a hybrid characterization method that depended on both experiments and simulations to estimate the HGMs mechanical properties. The experimental method utilizes a nano-indenter with a spherical sapphire tip of 500 μm in diameter. Each HGM was uniaxialy compressed under the indenter to yield the stiffness, diameter, and the force-displacement at fracture of each HGM tested. ABAQUS™ was used to numerically model an HGM of mean diameter and stiffness to obtain a relation between the mechanical and geometrical properties of each HGM to its thickness, and investigate the development of stresses on an HGM during its uniaxial compression. The data show large scatter in the measured stiffness of each HGM as a function of diameter. The authors conjecture this is due to a large fluctuation of the microsphere thickness. Finally, the work necessary to deform an HGM was successfully correlated to its radius-to-thickness ratio. This gives us a unique insight on the force-displacement behavior against the geometrical features of HGMs.
LAND QUALITY AND LAND ALIENATION ON THE DRY FARMING FRONTIER

From 1900 to 1920 the land alienation process in the northern Great Plains was primarily influenced by location, not land quality, in a railroad-dominated settlement pattern. Homesteaders in Sheridan County, MT and Bowman County, ND generally did not settle on the best lands first and assessed the productive acreage on their claims inaccurately. In peripheral locations, homesteaders who perceived soil resources correctly took the higher quality lands first. Evidence suggests abandonment was most likely on poorer soils, least likely on the best soils. Inability to perceive soil capability exacerbated an unstable situation that, with drought, led to out-migration.
A mAb to the β2-leukocyte integrin Mac-1 (CD11b/CD18) reduces intimal thickening after angioplasty or stent implantation in rabbits

Leukocytes are recruited early and abundantly to experimentally injured vessels, in direct proportion to cell proliferation and intimal growth. Activated circulating leukocytes and Mac-1 (CD11b/CD18, alphaMbeta2) expression are markers of restenosis risk in patients undergoing angioplasty. As angioplastied vessels lack endothelium but have extensive fibrin(ogen) and platelet deposition, we hypothesized that Mac-1-dependent adhesion to fibrin(ogen) is an important determinant of leukocyte recruitment and function, which may in turn promote intimal growth. To study this hypothesis we administered M1/70, an anti-CD11b blocking mAb, to rabbits (1 mg/kg i.v.) immediately before, and every 48 hr for 3, 6, or 14 days after, iliac artery balloon denudation or deeper stent-induced injury. M1/70, which bound to isolated rabbit monocytes and dose-dependently inhibited Mac-1-mediated fibrinogen binding in vitro, reduced leukocyte recruitment more than 2-fold 3, 6, and 14 days after injury. Neointimal growth 14 days after injury was markedly attenuated by treatment with M1/70 (intimal area after balloon injury, 0.12 +/- 0.09 mm2, compared with 0.32 +/- 0.08 mm2 in vehicle-treated controls, P < 0.01, and 0.38 +/- 0.08 mm2 in IgG-treated controls, P < 0.005; intimal area after stent injury, 0. 56 +/- 0.16 mm2, compared with 0.84 +/- 0.13 mm2 in vehicle-treated controls, P < 0.05, and 0.90 +/- 0.15 mm2 in IgG-treated controls, P < 0.02). Mac-1 blockade reduces experimental neointimal thickening, suggesting that leukocyte recruitment to and infiltration of injured arteries may be a valid target for preventing intimal hyperplasia.
Soil carbon sequestration beneath hybrid poplar plantations in the North Central United States

Hybrid poplar plantations grown on tilled agricultural lands previously in prairie, sequester significant quantities of soil carbon. Comparisons are made between hybrid poplar plantations and adjacent row crops or mowed grass. Establishing and tending plantations often results in early soil carbon loss, but soil carbon is significantly related (positive) to tree age. Increasing tree age eventually results in a net addition of soil carbon from plantations older than about 6 to 12 years of age. Soil carbon loss under trees occurred most frequently from the surface 30 cm early in the plantation history—evidence that the loss was due to mineralization. Soil carbon gain was most significant in the 30–50 cm layer and was attributed to tree root growth. Soil carbon accretion rate beneath 12- to 18-year-old poplar plantations exceeded that of adjacent agricultural crops by l.63 ± 0.16 Mg ha−1 yr−1. There was a significant crop × soil depth interaction for bulk density with bulk density lower beneath trees in the 0–30 cm layer and higher in the 30–50 cm layer. There was little evidence of carbon trapping of wind-blown organic detritus by tree plantations in the prairie environment.
Associations of Weight Status, Social Factors, and Active Travel Among College Students

Background: Active travel (AT) is associated with various health benefits and may help prevent the decline in physical activity during college years. Purpose: The purpose of this study was to examine the relationship of several factors with AT to campus by weight status. Methods: Students at a large northeastern US campus completed an online survey about demographics, height/weight, frequency and mode of travel to/around campus, and environmental influences for travel choices. Participants were dichotomized into healthy weight ( < 25 kg/m2, n = 552, 72.3%) and overweight ( ≥ 25 kg/m2, n = 211, 27.7%) categories. Descriptive and inferential analyses examined relationships and differences between weight categories. Logistic regression models examined the associations with demographic, psychological, residential, social, and environmental variables with participation in AT. Results: Participants were primarily white (85.3%) and female (62.7%). Healthy weight students were more likely to report AT to campus a...
What's at stake in the agent-structure debate?

Recent developments in the philosophy of science, particularly those falling under the rubric of “scientific realism,” have earned growing recognition among theorists of international relations but have failed to generate substantive programs of research. Consequently, the empirical relevance of much philosophical discourse, such as that centering on the agent-structure problem in social theory, remains unestablished. This article attempts to bridge the gap between the philosophy and practice of science by outlining a model of international structure based on the principles of scientific realism and by considering its implications for a structural research program in international relations theory. Appealing to Imre Lakatos's methodology of theorychoice, the article presents an ontological case for adopting a “transformational” model of structure over the “positional” model developed in the work of Kenneth Waltz. The article demonstrates that the positional approach offers no conceptual or explanatory hold on those features of the international structure that are the intended products of state action. In conclusion, the article argues that the stakes in the agent-structure debate include the capacity to generate integrative structural theory and the ability to theorize the possibilities for peaceful change in the international system.
Crystal Growth of Organohectorite Clay As Revealed by Atomic Force Microscopy

Noncontact atomic force microscopy, commonly referred to as “tapping mode” AFM, has been used to scan primarily the morphological features of growing hectorite clay crystallites synthesized in the presence of organoammonium cations. The use of such cations allows larger crystals to form in this system, making study by AFM feasible. This is the first time that temporal “snapshots” of a clay's nucleation and crystallization processes have been presented. The observed view does not support the perhaps predicted scene of small crystallites slowly ripening into large plates. Instead, larger aggregates appear to coalesce from numerous small crystallites that are closely associated in globular networks similar in appearance to “strings of pearls” at the initial stages of crystallization.
Universality for locally Szegő measures

In this paper, we use asymptotic estimates of the Christoffel functions associated with regular measures satisfying Szego's condition locally to extend a recent universality result by D.S. Lubinsky. As a consequence, we obtain under the same conditions an extension of a very precise zero-spacing result of Levin and Lubinsky.
Lambda transducing phages carrying plasmid R100 replication genes.

VAλ73, a λ bacteriophage carrying R100 replication genes, maintains itself as an independent plasmid under conditions in which the λ replication genes are inactive.
Structure and expression of the human septin gene HCDCREL-1

Abstract Septins are a family of highly conserved filament-forming proteins that have been shown to mediate cytokinesis and cytoskeletal organization in fungi and Drosophila. The gene encoding the human septin family member HCDCREL-1 has been shown to be transcribed from a locus immediately adjacent to that of the platelet glycoprotein (GP) Ib β. The HCDCREL-1 gene possesses a non-consensus polyadenylation signal that apparently is not efficiently utilized, resulting in the expression of a readthrough transcript also containing the platelet GPIb β coding region. As a first step in understanding the regulation and function of HCDCREL-1, we have analyzed the structure of this gene and characterized its expression in a variety of human cells. Our results indicate that the gene is expressed at high levels in platelets and neural tissue, and is transcriptionally complex.
Concerning the Limiting Behavior of Time-dependent Slope Winds

Abstract Some controversy has developed concerning the results of analytical katabatic-flow models, which appear to show that slope flows become infinite for zero slope angles and adiabatic lapse rates. It is shown that in the limits of zero slope angles and adiabatic conditions an indeterminate form is on hand, and the application of L'Hopital's rule is in order. Application of the rule results in limiting cases that agree with physical expectations and the original slope-flow model evaluated for a zero slope or adiabatic lapse rate.
Cognitive impairment and dementia in basal ganglia disorders.

We present an update focusing on research from the past 2 years on cognitive impairment and dementia in basal ganglia disorders, including Huntington’s disease, progressive supranuclear palsy, Parkinson’s disease, Parkinson’s disease dementia, and dementia with Lewy bodies. In addition to the many recent papers that aim to refine descriptions of the cognitive phenotypes in the basal ganglia disorders, the current literature addresses the use of cognitive assessment in differential diagnosis of clinically overlapping disorders, the effects of surgical and pharmacologic treatments on cognitive functions, and the relationship between cognitive impairment and functional disability. We also discuss opportunities for enhancing the understanding of cognition in basal ganglia disorders through the use of improved study design and assessment strategies.
The cross section for double Compton scattering

Employing elementary methods in nonrelativistic quantum electrodynamics, the cross section for gamma sub 0 + e yields e + gamma + gamma is computed for arbitrary energy in the spectrum of the outgoing photons. The final result is given, differential in the energy of one of these photons, for the case where the incident photon is unpolarized and has energy E sub 0 much less than mc-squared, a polarization sum and angular integration being performed for the final-state photons. The cross section has a simple algebraic form resulting from contributions from the sum of squared direct and exchange amplitudes; interference terms from these amplitudes do not contribute to the angular-integrated cross section.
Neuroscience: Patterns from the brain

Vincent A. Billock recommends an introduction to the mathematics of geometric hallucinations.
An exact derivation of contact resistance to planar devices

A mixed boundary-value problem is formulated for an imperfect rectangular contact to a semiconducting sheet (layer). An exact model for derivation of contact resistance is developed and its solution by conformal mapping and eigenfunction expansion is presented. The expression for contact resistance is similar to that for a perfect (lossless) contact but includes an additional term containing the lowest-order coefficient in the infinite series expansion of the complex potential function. The calculated contact resistances are compared with those obtained from three approximate models: lossless contact, transmission line, and extended transmission line models. The extended transmission line model appears to be a very satisfactory approximation provided the ratio of contact length to sheet thickness is no less than 0.5.
Neuroprotectin D1/protectin D1 stereoselective and specific binding with human retinal pigment epithelial cells and neutrophils

Retinal pigment epithelial (RPE) cells, derived from the neuroectoderm, biosynthesize the novel lipid mediator neuroprotectin D1 (NPD1) from docosahexaenoic acid (DHA) in response to oxidative stress or to neurotrophins, and in turn, elicits cytoprotection. Here, we report the identification of a 16,17-epoxide-containing intermediate in the biosynthesis of NPD1 in ARPE-19 cells from 17S-hydro-(peroxy)-docosahexaenoic acid. We prepared and isolated tritium-labeled NPD1 ([(3)H]-NPD1) and demonstrate specific and high-affinity stereoselective binding to ARPE-19 cells (K(d)=31.3+/-13.1 pmol/mg of cell protein). The stereospecific NPD1 interactions with these cells in turn gave potent protection against oxidative stress-induced apoptosis, and other structurally related compounds were weak competitors of NPD1 specific binding. This [(3)H]-NPD1/PD1 also displayed specific and selective high affinity binding with isolated human neutrophils (K(d) approximately 25 nM). Neither resolvin E1 nor lipoxin A(4) competed for [(3)H]-NPD1/PD1 specific binding with human neutrophils. Together, these results provide evidence for stereoselective specific binding of NPD1/PD1 with retinal pigment epithelial cells as well as human neutrophils. Moreover, they suggest specific receptors for this novel mediator in both the immune and visual systems.
Games fathers and mothers play with their infants

Both fathers and mothers successfully engaged their infants one to six months of age in interactive games in a laboratory play situation. Both parents played almost one game per minute with their infants. Mother played more conventional limb movement games and more distal, visual, attention maintaining games while fathers played more proximal, arousing, idiosyncratic limb movement games with their infants. Interactive games with parents even during the first six months of infancy provide differential experiences for the infant. These games may have developmental significance in selectively facilitating the acquisition of social and cognitive skills.
Unearthing the past

A Complete Manual of Field Archaeology: Tools and Techniques of Field Work for Archaeologists. By Martha Joukowsky. Pp.630. Hbk ISBN 0-13-162164-5; pbk ISBN 0-13-162156-4. (Prentice-Hall: 1980.) Hbk $29.95, £22.45; pbk $14.95, £11.20.
Maternal condition and facultative sex ratios in populations with overlapping generations.

Abstract: Facultative investment in offspring sex is related to maternal condition in many organisms. In mammals, empirical support for condition‐dependent sex allocation is equivocal, and there is some doubt as to theoretical expectations. Much theory has been developed to make predictions for condition‐dependent sex ratios in populations with discrete generations. However, the extension of these predictions to populations with overlapping generations (OLGs; e.g., mammals) has been limited, leaving doubt as to the specific prediction for maternal‐condition‐dependent sex ratios in mammals. We develop a population genetics model that incorporates maternal effects on multiple offspring fitness components in a population with OLGs. Using a rare‐gene and evolutionarily stable strategy approach, we demonstrate that sex ratio predictions of this model are identical to those for equivalent discrete generations models. We show that the predicted sex ratios depend on the sex‐specific ratio of Ro (offspring lifetim...
Clinical Reasoning: A 44-year-old man with a 3-month history of hiccups

A 44-year-old right-handed African American man with a 1-year history of seizures was admitted for further evaluation. During a previous hospitalization for status epilepticus, MRI revealed a brain lesion, but the patient refused biopsy. Over a 3-month period, he developed unrelenting hiccups which fluctuated in frequency. His only other symptom was headache relieved by acetaminophen. The patient denied photophobia, phonophobia, and visual changes associated with the headache. He had a history of hypertension and a left above-the-knee amputation (AKA) for osteosarcoma as a child. His general medical examination revealed the left AKA but was otherwise unremarkable. He was alert, oriented, and executive functions were intact. Vision was 20/20 in both eyes, extraocular movements were intact, and pupils were equal and reactive. There was no papilledema. He had a flattened right nasolabial fold. Motor, sensory, and cerebellar function were intact. Hiccups persisted throughout the interview. Their frequency remained relatively constant, and they often interrupted the patient's speech. ### Questions for consideration: 1. How are hiccups classified based on their time course? 2. How are hiccups generated and what is the pathophysiology in this patient? GO TO SECTION 2 Hiccups, or singultus, result from sudden closure of the glottis along with contraction of the inspiratory muscles.1 Bouts of hiccups lasting up to 48 hours are considered physiologic. However, persistent (lasting up to 2 months) or intractable (lasting greater than 2 months) hiccups have various etiologies.2 The pathophysiology of hiccups is not entirely clear, but …
PEM stack test and analysis in a power system at operational load via ac impedance

Abstract This paper presents a method for collecting ac impedance data from a commercial PEFC power system at operational loads. The PEM fuel cell stack in the power system, including 47 MEAs, was operated using room air and pure hydrogen (>99.99%). For a stack test in the power system, the power source for the embedded controller board was simultaneously switched from the fuel cell stack to a similar external power source after the system reached a steady temperature. The PEM fuel cells in the stack were tested by collecting the ac impedance data at different current levels. By using ac impedance, a single fuel cell, a group of fuel cells, and a complete stack were then tested without the embedded control devices for ohmic, activation, and mass transport losses. The ohmic resistance for each cell component in the stack was obtained as 117 mΩ cm 2 at operational loads from 2.5 A to 35 A. The membrane thickness was further estimated as ca. 51–89 μm. Resistances from ohmic conduction, anode/cathode activation, and mass transport were measured and discussed using the Nyquist plots from the ac impedance spectra.
Cardiac arrhythmias induced by guanethidine in cats anesthetized with halothane.

Abstract Rapid i.v. administration of guanethidine provokes severe and susteined ventricular arrhythmieas in cats anesthetized with halothane. The arrhythmias premature ventricular exciations, multifocal ventricular rhythm, bigeminy, trigeminy and ventricular tachycardia. They begin in about 20 sec and last from 4 to 19 min. By comparison, a standard dose of noradrenaline (10 ωg/kg) induces ventricular arrhythmias which develop in about 12 sec and continue for 1–2.5 min. Pretreatment with β-adrenoceptor blocking drugs prevents arrhythmias from both drugs, and pretreatment with imipramine or reserpine prevents arrhythmias from guanethidine but not noradrenaline. The adrenergic neuron blocking action of guanethidine does not alter the arrhytmogenic action of guanethidine since arrhythmias can still be produced after adrenergic neuron blockade. These results indicate that guanethidine causes arrhythmias by releasing noradrenaline from cardiac adrenergic neuron storage sites and, therefore, point out the vulnerability of the heart to arrhythmias when noradrenaline-releasing drugs interact with halogenated hydrocarbon anesthetics.
Fluids with highly directional attractive forces. I. Statistical thermodynamics

A new formulation of statistical thermodynamics is derived for classical fluids of molecules that tend to associate into dimers and possibly highers-mers due to highly directional attraction. A breakup of the pair potential into repulsive and highly directionally attractive parts is introduced into the expansion of the logarithm of the grand partition function in fugacity graphs. The bonding by the directional attraction is used to classify the graphs and to introduce a topological reduction which results in the replacement of the fugacity by two variables: singlet densityρ and monomer densityρ 0. Results for the thermodynamic functions as functionals ofρ andρ 0 are given in the form of graph sums. Pair correlations are analyzed in terms of a new matrix analog of the direct correlation function. It is shown that the low-density limit is treated exactly, while major difficulties arise when the Mayer expansion, which employs onlyp, is used. The intricate resummations required for the Mayer expansion are illustrated for the case where dimers are the only association products.
The Activity of a Small Lytic Peptide PTP-7 on Staphylococcus aureus Biofilms

One of the most important features of bacterial biofilms is their resistance to antibiotics and to the host immune system. In this study, we have found that a small lytic peptide, PTP-7, is very potent to Gram-positive bacteria and is able to kill antibiotic sensitive and resistant Staphylococcus aureus indiscriminately. Further studies have revealed that despite being a cationic peptide, the antibacterial activity of PTP-7 was not affected by the negatively charged extracellular polymeric substance (EPS) of biofilms. PTP-7 could diffuse into the deep layer of S. aureus biofilms to kill bacteria inside biofilms efficiently and effectively. Neither the high concentrations of metal ions nor the acidic pH in biofilms affected the activity of peptide PTP-7. It seems that the unique sequence/structure together with the resistant bacteria killing ability of peptide PTP-7 confers its anti-biofilm activity. This study sheds new light on the treatment of bacterial biofilms, especially various biofilm related infections.
Gonadal cycle of Crassostrea gigas kumamoto (Thunberg) in Yaquina Bay, Oregon and optimum conditions for broodstock oysters and larval culture

Abstract The reproductive cycle of Kumamoto oysters collected from commercial oyster grounds in Yaquina Bay, Oregon, was determined monthly over a 3-year period. Gonads contained some ripe gametes throughout the year. Maximum frequency of sexually mature oysters occurred in August–September and declined rapidly in October–November to a minimum in March. Gametogenesis commenced in May and the first mature ova appeared in June–July. Conditioning for spawning trials was conducted at 20 °C and 24 °C four times a year. At 24 °C production of gametes occurred 2 to 4 weeks earlier than at 20 °C. By beginning conditioning in May or June, the conditioning period in the laboratory could be reduced by 2 to 6 weeks. Larval survival and number of spat collected was also increased by reducing the laboratory conditioning period. In experiments carried out at five temperatures and five salinities, the optimum conditions for larval rearing ranged from 24 to 28 °C and from 20 to 25%o.
Congenital toxoplasmosis in triplets.

mas and lymphoid malignancies. 6. 7 However, the st imulus for the product ion and the biologic significance of A N A in mal ignancy remain unknown. The possibility of the coexistence of SLE and A L L must be considered in our patients. SL E has been reported in association with a variety of malignancies, 8-~2 but the nature and the pathogenesis of these associations remain enigmatic. Mal ignancy has been reported to precede, 8,9 occur s imultaneously with, ~~ or appear years af ter the diagnosis of SLE." , ~2 Despite a number of hypotheses, it remains unclear whether S L E predisposes to mal ignancy or vice versa, or whether thei r association is mere coincidence. Findings in our patients serve to i l lustrate tha t A L L in children may mimic SLE. A bone marrow examinat ion is therefore p ruden t in any child with a presumptive diagnosis of S L E if the clinical course is atypical. I t is par t icular ly impor tan t to exclude leukemia in any pat ient in whom corticosteroid therapy is ant icipated.
Microfabricated Systems and Assays for Studying the Cytoskeletal Organization, Micromechanics, and Motility Patterns of Cancerous Cells

Cell motions are driven by coordinated actions of the intracellular cytoskeleton – actin, microtubules (MTs) and substrate/focal adhesions (FAs). This coordination is altered in metastatic cancer cells resulting in deregulated and increased cellular motility. Microfabrication tools, including photolithography, micromolding, microcontact printing, wet stamping and microfluidic devices have emerged as a powerful set of experimental tools with which to probe and define the differences in cytoskeleton organization/dynamics and cell motility patterns in non-metastatic and metastatic cancer cells. In this review, we discuss four categories of microfabricated systems: (i) micropatterned substrates for studying of cell motility sub-processes (for example, MT targeting of FAs or cell polarization); (ii) systems for studying cell mechanical properties, (iii) systems for probing overall cell motility patterns within challenging geometric confines relevant to metastasis (for example, linear and ratchet geometries), and (iv) microfluidic devices that incorporate co-cultures of multiple cell types and chemical gradients to mimic in vivo intravasation/extravasation steps of metastasis. Together, these systems allow for creating controlled microenvironments that not only mimic complex soft tissues, but are also compatible with live cell high-resolution imaging and quantitative analysis of single cell behavior.
Supramolecular Stabilization of α,ω-Diphenylpolyynes by Complexation to the Tridentate Lewis Acid [o-C6F4Hg]3

The interaction of trimeric (perfluoro-o-phenylene)mercury ([o-C6F4Hg]3, 1) with α,ω-diphenylpolyynes containing 4, 6, 8, and 12 sp carbon atoms in CH2Cl2 leads to the formation of (1)2·Ph(C⋮C)2Ph (2), 1·Ph(C⋮C)3Ph (3), (1)2·Ph(C⋮C)4Ph (4), and (1)2·Ph(C⋮C)6Ph·CH2Cl2 (5). Adducts 2−4 have been characterized by elemental analysis, X-ray crystallography, infrared and fluorescence spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In the solid state, the α,ω-diphenylpolyynes, which are approximately planar, are associated to molecules of 1 on either side of the molecular plane via secondary Hg−π interactions. The acetylenic stretches of 2−5 measured by IR spectroscopy are essentially identical with those of the free polyyne. While adducts 3−5 give rise to only faint emissions upon UV irradiation, the luminescence spectrum of 2 indicates complete quenching of the fluorescence and displays a heavy-atom-induced emission whose energy and vibronic progression are identical with those...
ECS effects: The PRE

Sixty-four naive male albino rats were trained to leverpress for sucrose using a discrete trial procedure. Half of the Ss were trained on a continuous reinforcement schedule (CRF), and the other half were trained on a fixed-ratio schedule (FR). Following acquisition, on treatment day, a leverpress produced footshock followed by ECS (SECS), footshock only (SO), ECS only (ECSO), or no treatment (OO). Results of an extinction test 24 h after treatment showed that: (1)ECS produced apparent amnesia for footshock; (2) ECS eliminated the partial reinforcement effect (PRE); (3) footshock appeared to be a more effective suppressor in FR- than in CRF-trained Ss; (4) ECS alone produced a significantly increased rate of responding for CRF-trained Ss and a nonsignificant increased rate of responding for FR-trained Ss.
Transforming from centers of learning to learning health systems: the challenge for academic health centers.

Health care organizations face intensifying pressure to achieve the triple aims of better patient experience, better health, and affordability. Although all health systems grapple with these imperatives, the tripartite mission of research, education, and patient care presents particular challenges for academic health centers in responding to demands for high-value, patient-centered care and population health. In this Viewpoint, we propose that health reform offers an opportunity for academic health centers to create new synergies across mission areas to become exemplary learning health systems.
Update on Kaposi's Sarcoma: A Gammaherpesvirus- induced Malignancy.

Since the beginning of the AIDS epidemic, Kaposi’s sarcoma (KS) has been one of the most visible manifestations of this disease and one of the most distressing for affected patients. The discovery in 1994 of a new gammaherpesvirus, called Kaposi’s sarcoma-associated herpesvirus, has led to increased understanding of the pathogenesis of this disease and the potential for new specific therapy. In addition, the development of highly active antiretroviral therapy has had a substantial impact on the incidence of KS in countries where it is available and on the course of established disease. Finally, recent advances in our understanding of angiogenesis have the potential of leading to new KS therapies. In this article we review some of the recent advances in the epidemiology and pathogenesis of KS, review the current treatment of this disease, and discuss several therapeutic approaches that are now under development.
The radiologist as direct public educator: impact of sessions demystifying select cancer screening imaging examinations.

Purpose The aim of this report is to describe our early experience with radiologist-led direct public education about imaging-based cancer screening examinations, with a focus on the level of satisfaction and the educational impact reported by session participants. Methods Subspecialty radiologists provided 1-hour educational sessions to small lay public audiences covering breast, prostate, and lung cancer screening, focusing on key radiologic screening tests. Subsequently, session participants completed a survey pertaining to their levels of satisfaction and the perceived impact of the sessions on knowledge of the diseases and relevant screening tests; results from all topic sessions were pooled for analysis. Results One hundred nineteen participants attended a total of 144 sessions. The large majority of respondents agreed or strongly agreed that the sessions increased their understanding (95.4%), they gained information not obtained from clinic visit (88.1%), seeing radiology images helped their understanding (92.6%), they felt more involved in their own care (85.8%), they felt more prepared to undergo screening tests (87.4%), they were satisfied with the sessions' format (93.3%) and content (96.2%), their main questions were answered (88.3%), they would be interested in similar future radiologist-led sessions (88.5%), and they would recommend the sessions to friends (93.9%). The provided information (43.1%) and images (34.7%) were identified as the most helpful aspects of the sessions. Conclusion Radiologist-led direct public education sessions about imaging-based cancer screening examinations yield high levels of audience satisfaction and add value to the public's understanding of the role of radiology and radiologists. Our experience may provide an encouraging model for other radiology practices in pursuing similar endeavors.