cssi/SciSciGPT-SciSciNet huggingface dataset:
Conspecific presence and microhabitat features influence foraging decisions across ontogeny in a facultatively social mammal

Natural selection is expected to favor the evolution of threat-sensitive behaviors that permit individuals to adaptively detect and respond to danger. However, because time allocated to vigilance reduces the amount of time that is available for energy acquisition, foraging in the face of predation can impose an evolutionary trade-off. Optimal foraging theory therefore predicts that risk-taking decisions should vary in response to perceived levels of threat. Our goal here is to disentangle the relative contributions of conspecific presence, ecological factors, and individual traits on two measures of vigilance in free-living California ground squirrels (Otospermophilus beecheyi). This facultatively social and ecologically flexible rodent represents a major source of prey in California grasslands. Over a 5-year period, we collected 386 focal animal surveys on 156 free-living individuals residing at two colony sites. Individuals were most vigilant in conditions for which predation risk was highest, such as when foraging alone and on flat areas with low vegetative cover. In general, juvenile foragers were more gregarious but less vigilant than adult foragers. Although all animals—regardless of age or sex—generally decreased their intensity of vigilance as group size increased, only adults decreased their time allocated to vigilance in response to conspecific presence. Thus, grouping consistently buffered the costs of foraging for risk-averse adults, but the benefits of conspecific presence were less salient for juveniles. Taken together, our findings highlight the importance of context in shaping foraging decisions and offer insights into the suite of factors mediating decision-making in socially and ecologically variable environments. Animals face trade-offs when foraging in the face of predation, but the capacity for individuals to respond appropriately to subtle changes in context-dependent threats remains poorly understood. We studied antipredator vigilance by the California ground squirrel, a flexible species that may forage alone or in small groups of various sizes and in habitats that vary in their protective value from predators and the ease at which prey may detect predators. Although adults are more sensitive to changes in group size, all animals detected context-dependent danger to some extent. Our findings offer insights into the multiple factors that prey respond to when making foraging decisions, suggesting that animals possess the ability to integrate disparate sources of information about danger to optimize energy gain.
LONG-TERM FOLLOW-UP OF SKELETALLY IMMATURE PATIENTS WITH THE PHYSEAL-SPARING COMBINED EXTRA-/INTRA-ARTICULAR ILIOTIBIAL BAND ACL RECONSTRUCTION: KINEMATIC AND KINETIC RESULTS

Background:Anterior cruciate ligament (ACL) tears are among the most devastating orthopaedic injuries affecting young athletes, especially when they occur in children and adolescents. Growing inter...
Chemotherapy-related outcomes in triple-negative breast cancer.

e12049Background: Triple-negative breast cancer (TNBC) is associated with a poor prognosis when compared to hormone receptor positive breast cancers. Anthracycline-based regimens (ABRs) are mainsta...
The Power of Place: the Transfer of Charismatic Authority to an American Ashram

It has largely been assumed that when an intentional community loses its charismatic leader for one reason or another, the group will most likely disband unless that individual’s charisma has become routinized. The Kashi Ashram in Sebastian, Florida, is a spiritual community that was established, thanks to the vision of their Guru, Ma Jaya Sati Bhagavati. Her students were so devoted to her that her physical death in 2012 could have initiated a crisis in the community. Although bureaucratic offices had been established to carry out some of the necessary functions of the Ashram, no one came close to filling her role as a spiritual teacher. And yet, more than 6 years later, new members are still joining the community and the way they describe Ma’s presence in their lives is little different from how older members that knew Ma in this lifetime talk about her. While I do not disagree that the routinization of charisma is an important step in ensuring the longevity of new religious movements, in this paper, I argue that an individual’s charisma may be transferred to a geographic place such that the Ashram becomes an active agent in the attraction and retention of new members.
An experimental investigation of asphaltene stability in heavy crude oil during carbon dioxide injection

Carbon dioxide (CO2) injection is one of the most applied enhanced oil recovery methods in the hydrocarbon industry, since it has the potential to increase oil recovery significantly and can help reduce greenhouse gases through carbon storage in hydrocarbon reservoirs. Carbon dioxide injection has a severe drawback, however, since it induces asphaltene precipitation by disrupting the asphaltene stability in crude oil that bears even the slightest asphaltene concentration. This can result in severe operational problems, such as reservoir pore plugging and wellbore plugging. This research investigates some of the main factors that impact asphaltene stability in crude oil during CO2 injection. Initially, asphaltene precipitation, flocculation, and deposition were tested using visual tests without CO2 in order to evaluate the effect of oil viscosity and temperature on asphaltene stability and content in the crude oil. The results obtained from the visualization experiments were correlated to the Yen–Mullins asphaltene model and were used to select the proper chemical to alter the oil’s viscosity without strongly affecting asphaltene stability. After performing the visual asphaltene tests, a specially designed filtration vessel was used to perform the oil filtration experiments using filter membranes with a micron and nanometer pore size. The effect of varying CO2 injection pressure, oil viscosity, filter membrane pore size, and filter membrane thickness on asphaltene stability in crude oil was investigated. The results were then correlated with the Yen–Mullins asphaltene model to characterize the asphaltene size within the oil as well. Results showed that as the oil viscosity increased, the asphaltene concentration in the oil also increased. Also, the asphaltene concentration and filter cake thickness increased with the decrease in filter membrane pore size, since the asphaltene particles either plugged up the smaller pores, or the asphaltene nanoaggregates were larger than the pore sizes, and thus the majority of them could not pass. This research studies asphaltene instability in crude oil during CO2 injection in different pore sizes, and correlates the results to the principle of the Yen–Mullins model for asphaltenes. The results from this research can help emphasize the factors that will impact asphaltene stability during CO2 injection in different pore sizes in order to help reduce asphaltene-related problems that arise during CO2 injection in hydrocarbon reservoirs.
Swarm Optimization Algorithm for Road Bypass Extrapolation

Ant Colony Optimization (ACO) algorithms work by leveraging a population of agents that communicate through interaction with deposited “pheromone,” and have been applied in various configurations to the long-standing problem of identifying trafficable terrain from aerial imagery. While these approaches have proven successful in highlighting paved roads in urban, highly-developed sites, they tend to fail in peri-urban and rural locations due to the lower frequency of unnatural features. In this work, we describe a workflow that uses site-specific, near-infrared and first-return LIDAR data to predict the “accessible space” of an image–i.e., the more open regions with shallow elevation gradient that may be readily traversible by both mounted (e.g., all-terrain vehicles) and dismounted forces. Collectively, these regions are supplied as input to an ACO algorithm, modified so that the agents perform a random walk weighted by local elevation change, which allows for a more comprehensive exploration of increasingly featureless imaged terrain. Performance of this workflow is evaluated using two study sites in the continental United States: the Muscatatuck Urban Training Center in rural Indiana, and Camp Shelby in Mississippi. Comparison of results with ground-truth datasets show a high degree of success in predicting areas trafficable by a wide variety of mobile units.
High temperature oxidation behaviors of SiON coated AISI 441 in Ar + O2, Ar+H2O, and Ar + CO2 atmospheres

Abstract Silicon oxynitride (SiON) coated AISI 441 was prepared by pyrolysis of a dip-coated perhydropolysilazane (PHPS) precursor polymer. The high temperature oxidation behaviors of SiON coated AISI 441 substrates were studied in Ar + O2, Ar+H2O, and Ar + CO2 atmospheres at 800 °C for 100 h. The SiON coated AISI substrates showed better performance in all three atmospheres compared to the uncoated AISI 441 substrate. This improvement was attributed to the dense, crack-free SiON coatings, which provided complete separation between oxidizing species and the steel substrate. A thin oxide scale was observed on top of the SiON coating for all the atmospheres, which was attributed to the reactions between the oxidizing species in the atmosphere and the metallic species (Cr, Mn, and Fe) diffused through the SiON coating from the AISI 441 substrate.
Etiological Explanations : Illness Causation Theory

Theory of illness causation is an important issue in all biomedical sciences, and solid etiological explanations are needed in order to develop therapeutic approaches in medicine and preventive interventions in public health. Until now, the literature about the theoretical underpinnings of illness causation research has been scarce and fragmented, and lacking a convenient summary. This interdisciplinary book provides a convenient and accessible distillation of the current status of research into this developing field, and adds a personal flavor to the discussion by proposing the etiological stance as a comprehensive approach to identify modifiable causes of illness. Key Features • Provides a synthesis of the epidemiological and philosophical concepts in this growing research area • Gives an accessible overview of current methods in biomedical causal metaphysics what is a cause of illness? and epistemology how do we identify it? • Proposes a novel approach that integrates modern epidemiological methodology and recent theories from philosophy of science Written for postgraduate students and researchers in the health and biomedical sciences, including those undertaking courses in the philosophy of medicine/science, public and global health, introduction to epidemiology, research methods, and advanced reasoning, the content will also be of interest to practicing public health workers, biomedical scientists, and physicians. ABOUT THE AUTHOR Olaf Dammann is Professor and Vice Chair of Public Health and Community Medicine at Tufts University School of Medicine, Boston, Massachusetts, USA; as well as a Professor in the Department of Gynecology and Obstetrics at Hannover Medical School, Hannover, Germany. Cover image: Mask used by "Eskimo" shaman in causation of illness. Credit: Wellcome Collection. CC BY https://creativecommons.org/licenses/by/4.0
Plasma Metabolomic Profiling in Patients with Rheumatoid Arthritis Identifies Biochemical Features Indicative of Quantitative Disease Activity

Background: Rheumatoid arthritis (RA) is a chronic, autoimmune disorder characterized by joint inflammation and pain. In patients with RA, metabolomic approaches, i.e., high-throughput profiling of small-molecule metabolites, on plasma or serum has thus far enabled the discovery of biomarkers for clinical subgroups, risk factors, and predictors of treatment response. Despite these recent advancements, the identification of blood metabolites that are predictive of quantitative disease activity remains an important challenge in precision medicine for RA. Herein, we use global plasma metabolomic profiling analyses to detect metabolites associated with, and predictive of, quantitative disease activity in patients with RA. Methods: Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was performed on a discovery cohort consisting of 128 plasma samples from 64 RA patients. The resulting metabolomic profiles were analyzed with two different strategies to find metabolites associated with Disease Activity Score-28 using C-reactive protein (DAS28-CRP). Mixed-effects regression models were used to identify metabolites differentially abundant between two disease activity groups (lower, DAS28-CRP 3.2); and to identify metabolites significantly associated with DAS28-CRP scores. A generalized linear model (GLM) was constructed for estimating DAS28-CRP using plasma metabolite abundances. For associating metabolites with CRP (an indicator of inflammation), metabolites differentially abundant between two patient groups (low-CRP, CRP 3.0 mg/L) were investigated. Results: We identified 33 metabolites differentially abundant between lower and higher disease activity groups (P < 0.05). Additionally, we identified 51 metabolites associated with DAS28-CRP (P < 0.05). A GLM based upon these 51 metabolites resulted in higher prediction accuracy (mean absolute error [MAE]+/-SD): 1.51+/-1.77) compared to a GLM without feature selection (MAE+/-SD: 2.02+/-2.21). The predictive value of this feature set was further demonstrated on a validation cohort of twelve plasma samples, wherein we observed a stronger correlation between predicted vs. actual DAS28-CRP (with feature selection: Spearmans rho = 0.69, 95% CI: [0.18, 0.90]; without feature selection: Spearmans rho = 0.18, 95% CI: [-0.44, 0.68]). Lastly, among all identified metabolites, the abundances of eight were significantly associated with CRP patient groups while controlling for potential confounders (P < 0.05). Conclusion: We demonstrate for the first time the prediction of quantitative disease activity in RA using plasma metabolomes. The metabolites identified herein provide insight into circulating pro-/anti-inflammatory metabolic signatures that can reflect disease activity and inflammatory status in patients with RA.
Water scrubbing for biogas upgrading: developments and innovations

Abstract Water scrubbing is a mature and efficient family of methodologies that is already widespread due to its simplicity and generally low costs. This chapter reviews the state of the art of the most common water scrubbing solutions applied to biogas upgrading, focusing on the main advantages (such as low methane loss, energy consumption, and maintenance costs), disadvantages, plant designs, and potential chemical promoters. The subject of methane slip mitigation by water scrubbing is also discussed in detail; indeed, while off-gas carbon dioxide release in the atmosphere can be considered carbon-neutral, methane in off-gas is a strong greenhouse gas, and furthermore its loss is associated with economic loss.
Raman Scattering and Luminescence by Molecules Adsorbed at Metal Island Films

It is now well established that surface roughness on a sub-microscopic scale plays an Important role in the enhancement of the Raman scattering (RS) by molecules adsorbed on metals.1–4 Moreover, recent work indicates that the optical absorption and luminescence by molecules adsorbed at a rough metal surface can also be enhanced.5–8
Abstract 197: Quantification of Absolute Myocardial Blood Flow With Contrast Enhanced MRI Approaching a Pixel Resolution: Validation vs. Microspheres

Introduction: Myocardial blood flow (MBF) can be estimated from gadolinium enhanced first pass perfusion MR imaging. We hypothesized that MBF can be quantified at approximately the pixel level from MR perfusion images. Results were validated with microspheres. Methods: Local hyperemia of MBF was induced in 7 dogs through intracoronary adenosine infusion. A dual-bolus contrast technique with steady-state free precession imaging was used to acquire first-pass perfusion MR images (1.5 Tesla). Fluorescent microspheres were the reference standard for absolute MBF (in ml/g/min) on 16 sectors (8 endocardial and 8 epicardial) of a mid ventricular slice. MR time intensity curves were analyzed on a pixel-by-pixel basis and converted to parametric maps using model constrained deconvolution. Results: Figure-1 shows a colorized MR perfusion pixel map with corresponding microsphere MBF on the same absolute color scale. Average MBF from microspheres were 5.1±1.5 ml/g/min in hyperemic sectors and 1.3±0.7 ml/g/min in control zones. Transmural estimates of MBF from MR matched well with microspheres (y=0.75x-0.50, r=0.89). For subsector comparison, both endocardial sectors (y=0.80x-0.41, r=0.91) and epicardial sectors (y=0.70x-0.63, r=0.85) showed good correlations of MBF between MR and microspheres. Bland Altman analysis showed no significant bias in all comparisons. Qualitatively, color perfusion maps were comparable to microsphere bull’s-eye plots in all animals. Conclusion: Myocardial blood flow can be quantified at approximately the pixel level on MR perfusion images. These methods could improve the objectivity of diagnosing coronary artery disease in patients.
Intrinsic neuromodulation in the Tritonia swim CPG: the serotonergic dorsal swim interneurons act presynaptically to enhance transmitter release from interneuron C2

Heterosynaptic enhancement of transmitter release is potentially very important for neuronal computation, yet, to our knowledge, no prior study has shown that stimulation of one neuron directly enhances release from an interneuron. Here, we demonstrate that in the marine mollusk Tritonia diomedea, the serotonergic dorsal swim interneurons (DSIs) heterosynaptically increase the amount of transmitter released from another interneuron, C2. Stimulation of a single DSI at physiological firing frequencies increases the size of synaptic potentials evoked by C2. This increase in synaptic efficacy is correlated with an increase in homosynaptic paired-pulse facilitation by C2. Thus, it is likely to be due to an enhancement of transmitter release from C2, rather than a postsynaptic action on the followers of C2. This is further supported by the fact that DSI stimulation enhances the strengths of all chemical synapses made by C2 within the swim network, regardless of their sign. Furthermore, DSI enhances the amplitude of C2 synaptic potentials recorded in neurons that DSI itself does not synapse with. Finally, DSI differentially modulates different synaptic inputs to the same postsynaptic target; while increasing C2- evoked EPSPs it simultaneously decreases the size of EPSPs evoked by other DSIs. The heterosynaptic facilitation of C2 synaptic potentials by DSI is not caused by a simple depolarization of C2, but may be a direct action on the transmitter release mechanism. This neuromodulatory effect, which is intrinsic to the circuitry of the central pattern generator for escape swimming in Tritonia, may be important for self-reconfiguration of the swim motor network.
Throwing good money after bad?: Nuclear power plant investment decisions and the relevance of sunk costs☆

Abstract Experimental psychologists and decision theorists suggest that managers are overly reluctant to terminate economically unviable projects and that they fail to ignore sunk costs. This study serves two purposes. First, it shows that the framework of prospect theory allows us to reconcile the sunk cost effect with some older, well-established ideas in investment decision-making. Secondly, the study investigates the external validity of the sunk cost research in the context of the U.S. nuclear power program. The empirical analysis is based on share price movements in reaction to, among other events, all plant completions and cancellations (over $50 million) prior to March 1984. The results are mixed. However, prudency reviews ordered by Public Service Commissions around the nation point to evidence consistent with the sunk cost fallacy.
Degradation of DNA in Haemophilus influenzae cells after X-ray irradiation: II. Comparison with theoretical models

Abstract Models of the kinetics of degradation of DNA in bacterial cells following exposure to X-rays are developed and tested using data obtained with various strains of Haemophilus influenzae cells. Different mathematical models allow for different initial distributions of DNA lengths, depending on cell phase and assumed replication model, and for unilateral or bilateral degradation from initiation points, which are taken as single-strand breaks. In order to explain the observed magnitude and time course of degradation an interruption-of-degradation probability, which may be interpreted as the result of an X-ray inducible inhibitor, is introduced. Interruption of degradation is interpreted as an early and essential, but not necessarily sufficient, step for repair of DNA. Empirical best fits to the kinetic data were obtained by iterative calculation methods based on varying the rate parameters. Depending somewhat on the strain and cell phase, the data seem best described by assuming bilateral degradation, perhaps at different rates, whose total for log phase wild-type cells is roughly 5 × 10 3 nucleotides/min and an interruption rate of about 0·03/min. For stationary phase the total degradation rate is greater and the probability of degradation unchanged. Differences in the kinetics between strains are discussed briefly.
SOCIAL STRUCTURE AND GENERATIONS IN ART: A Case Study of the Hebrew Theater

This study examines artistic innovations from the point of view of age structure and age stratification. Drawing on Mannheim's theory of generations, it describes and analyzes the history of the Hebrew theater, from its beginnings in 1917 to 1977, in terms of four theaters that were expressions of generation units. The study suggests that the crucial variable in explaining changes in artistic ideologies, contents, and styles of the Hebrew theater is Mannheim's concept of generation unit. The emergence and evolution of these generational theaters are explained in relation to changes in the demographic, political, and social structures of Israeli society during the historical era under consideration. Special emphasis is placed on the role of youth in originating artistic innovations and on the problems of maintaining and institutionalizing innovations. The history of Israel's theater, from its beginnings in 1917 to the present, is marked by four turning points, each resulting in profound changes in its artistic conventions, thematic as well as stylistic. The pivotal dates are the establishment of the Habima theater in 1917, the Ohel in 1925, the Cameri in 1944, and the Actors' Stage in 1966. The four theaters were products of basic changes in the demographic, political, and cultural settings of Israeli society. Each theater was an expression of a distinct generation unit' that differentiated itself from other units by rejecting prevalent artistic conventions and by creating new ones.
Boundary Conditions for Schwinger-Dyson Equations and Vacuum Selection

When attempting to solve a field theory or matrix model by using Schwinger-Dyson equations, one must address the problem that these equations do not possess a unique solution. This problem came to our attention when trying to numerically solve the equations for certain lattice field theories using a technique known as Source Galerkin [1], which is discussed elsewhere in these proceedings. It was found that to make the numerical method stable, one had to find some way of selecting the right boundary conditions. This led us to the more general question of how the boundary conditions are related to the phase diagram of a field theory or a matrix model. We shall summarize our work on this relation in this paper. Most of the details will appear elsewhere.
Scutellaria biotechnology: achievements and future prospects.

Plants of the genus Scutellaria (Family Lamiaceae) constitute one of the common components of Eastern as well as traditional American medicine. Skullcap is a North American perennial plant belonging to the genus Scutellaria. The genus is widespread in Northern Hemisphere represented by close to 400 species. Many species are rare, threatened, or endangered. Habitat destruction, urbanization, and poor seed set are the few reasons behind diminishing population of many skullcaps. Many skullcaps have showy, beautiful blooms with great potential as ornamental plants. Skullcap are used in alternative medicine as anti-inflammatory, antispasmodic, emmenagogue, nervine, sedative and strong tonic. We have developed a germplasm collection at Fort Valley State University and the populations are maintained in the greenhouse and through micropropagation. We have made significant headway in the areas of micropropagation, transformation for desired gene transfer and hairy root induction, extraction and HPLC analysis of targeted flavonoids, and clinical role of select flavonoids using glioma cell lines.
Orbital diameters: A new parameter for prenatal diagnosis and dating

Fetal inner orbital diameter and outer orbital diameter were measured in the occipital transverse and occipital posterior positions in 180 normal pregnancies. The outer orbital diameter was found to be closely related to the biparietal diameter. After a nomogram had been constructed, 463 patients whose fetuses were at risk for various anomalies were studied in two cases, hypotelorism was suspected because the orbital measurements fell below the 95% confidence limits, and this diagnosis was confirmed at the time of delivery. The conclusion is that, in situations in which fetal head position precludes accurate biparietal diameter determinations, the outer orbital diameter can often be obtained and used to estimate that variable and, therefore, gestational age. Furthermore, the nomogram constructed has proved to be a useful tool in diagnosing hypotension in utero. Theoretically, this should also be true of fetal hypertelorism.
No Way to Disengage: Themes of Engagement in The Remains of the Day and The Quiet American

Graham Green's The Quiet American and Kazuo Ishiguro's The Remains of the Day were both written by British authors, and both are set in the mid-1950s. This paper explores the themes of personal political engagement in both novels, and the way that those themes illustrate and comment upon British political attitudes during the mid-twentieth century.
VEGETABLES, FRUITS AND PHYTOESTROGENS IN THE PREVENTION OF DISEASES

The intake of 400-600 g/d of fruits and vegetables is associated with reduced incidence of many common forms of cancer, and diets rich in plant foods are also associated with a reduced risk of heart disease and many chronic diseases of ageing. These foods contain phytochemicals that have anti-cancer and anti-inflammatory properties which confer many health benefits. Many phytochemicals are colourful, and recommending a wide array of colourful fruits and vegetables is an easy way to communicate increased diversity of intake to the consumer. For example, red foods contain lycopene, the pigment in tomatoes, which is localized in the prostate gland and may be involved in maintaining prostate health, and which has also been linked with a decreased risk of cardiovascular disease. Green foods, including broccoli, Brussels sprouts and kale, contain glucosinolates which have also been associated with a decreased risk of cancer. Garlic and other white-green foods in the onion family contain allyl sulphides which may inhibit cancer cell growth. Other bioactive substances in green tea and soybeans have health benefits as well. Consumers are advised to ingest one serving of each of the seven colour groups daily, putting this recommendation within the United States National Cancer Institute and American Institute for Cancer Research guidelines of five to nine servings per day. Grouping plant foods by colour provides simplification, but it is also important as a method to help consumers make wise food choices and promote health.
Discovery of a novel amino acid racemase through exploration of natural variation in Arabidopsis thaliana

Plants produce diverse low-molecular-weight compounds via specialized metabolism. Discovery of the pathways underlying production of these metabolites is an important challenge for harnessing the huge chemical diversity and catalytic potential in the plant kingdom for human uses, but this effort is often encumbered by the necessity to initially identify compounds of interest or purify a catalyst involved in their synthesis. As an alternative approach, we have performed untargeted metabolite profiling and genome-wide association analysis on 440 natural accessions of Arabidopsis thaliana. This approach allowed us to establish genetic linkages between metabolites and genes. Investigation of one of the metabolite–gene associations led to the identification of N-malonyl-d-allo-isoleucine, and the discovery of a novel amino acid racemase involved in its biosynthesis. This finding provides, to our knowledge, the first functional characterization of a eukaryotic member of a large and widely conserved phenazine biosynthesis protein PhzF-like protein family. Unlike most of known eukaryotic amino acid racemases, the newly discovered enzyme does not require pyridoxal 5′-phosphate for its activity. This study thus identifies a new d-amino acid racemase gene family and advances our knowledge of plant d-amino acid metabolism that is currently largely unexplored. It also demonstrates that exploitation of natural metabolic variation by integrating metabolomics with genome-wide association is a powerful approach for functional genomics study of specialized metabolism.
Night Comes to the Cretaceous

In the 1960s and 1970s, geology witnessed an intellectual revolution. Recognition that seafloors spread and continents drift led to plate tectonics. NNight Comes to the Cretaceous addresses a second, still developing revolution—the view that impact cratering and other catastrophes may be the dominant phenomena driving evolution of the biosphere. The specific case analyzed is the hypothesis of the late Nobel laureate physicist Luis Alvarez and his colleagues that the Cretaceous/Tertiary (K-T) mass extinctions resulted from the impact of a 10-km-wide asteroid or comet. Once Alan Hildebrand focused geologists' attentions on the immense Chicxulub crater in the Yucatan, K-T deposits bearing impact signatures were found to be arrayed radially to the crater, itself dated precisely at the K-T age of 65 million years. By the early 1990s, the Alvarez hypothesis was thereby proved, despite protests of a few holdouts, whose scientific sloppiness is repeatedly scorned by this book's author, James Powell, director of the Los Angeles County Museum of Natural History.
The influence of cataract types on potential acuity meter results.

Abstract The records of 100 patients who had cataract surgery were reviewed to compare preoperative potential acuity meter (PAM) results with postoperative visual acuity. A PAM acuity was obtainable in 95 patients. In 82 of the 95 patients (86%), the PAM levels were within three lines of the outcome. Potential acuity meter results substantially lower (≤ four Snellen lines) than outcome generally occurred when posterior subcapsular (PSC) or PSC plus diffuse cortical or nuclear changes were present. We believe that the PAM projection can usually go around or through the nuclear sclerosis to give an accurate prediction. However, with PSC or mixed type, one may not always find a window in the cataract. Also, PSC or diffuse cortical cataracts may be particularly disruptive to the paracentral diffracted light that is an important factor in PAM acuity.
Solubilization of the Picrotoxinin Binding Receptor from Mammalian Brain

The binding sites for alpha-dihydropicrotoxinin (DHP), which is a ligand for the picrotoxin-sensitive component at the benzodiazepine-gamma-aminobutyric acid-receptor-ionophore complex, has been solubilized from rat brain, using 1% Lubrol. A new assay, which involves precipitation of the [3H]DHP-soluble protein complex by gamma-globulin and polyethylene glycol (PEG), followed by centrifugation, is described. The solubilized material bound DHP to two sites with apparent affinities of 0.038 and 1.85 microM. The binding of DHP to the solubilized receptors was inhibited by convulsant and depressant drugs with potencies similar to those required for membrane receptors. The ability of barbiturates to inhibit DHP binding to both solubilized and membrane receptors strongly suggests that barbiturates may interact with the picrotoxin binding component. These data suggest that ligand recognition properties of the picrotoxinin binding are not altered by solubilization. The binding was abolished by urea and partially destroyed by heating the soluble extract at 65 degrees C for 30 min. This new method of measuring the binding of ligands to the solubilized receptors by PEG centrifugation might be used successfully in other solubilization studies.
Solution structure and interdomain interactions of the Saccharomyces cerevisiae "TATA binding protein" (TBP) probed by radiolytic protein footprinting.

Although atomic-resolution crystal structures of the conserved C-terminal domain of several species of TBP and their complexes with DNA have been determined, little information is available concerning the structure in solution of full-length TBP containing both the conserved C-terminal and nonconserved N-terminal domains. Quantitation of the amino acid side chain oxidation products generated by synchrotron X-ray radiolysis by mass spectrometry has been used to determine the solvent accessibility of individual residues in monomeric Saccharomyces cerevisiae TATA binding protein (TBP) free in solution and in the TBP−DNA complex. Amino acid side chains within the C-terminal domain of unliganded full-length TBP that are predicted to be accessible from crystal structures of the isolated domain are protected from oxidation. Residues within the N-terminal domain are also protected from oxidation in both the absence and presence of DNA. Some residues within the DNA-binding “saddle” of the C-terminal domain are pro...
Resistance of Rat Pulmonary Alveolar Epithelial Cells to Neutrophil- and Oxidant-induced Injury

We have previously reported that rat pulmonary alveolar epithelial cells are resistant to neutrophil-generated oxidants in contrast to the situation described for endothelial cells. In the present study, we investigated the roles of intracellular catalase and glutathione-dependent reactions in providing protection against cytotoxic concentrations of H2O2 and stimulated neutrophils. Catalase was found to be instrumental in protecting epithelial cells because when inhibited by either azide or 3-amino-1,2,4-triazole, there was an increase in the cytotoxic effect of exogenous H2O2 and stimulated neutrophils. Associated with this potentiation of injury was a reduction in epithelial cell clearance of H2O2. Partial inhibition of glutathione-dependent reactions by depleting intracellular glutathione with buthionine sulfoximine or by inhibiting the enzyme glutathione reductase with 1,3-bis(2-chloroethyl)-1-nitrosourea also augmented the cytotoxic effect of both H2O2 and stimulated neutrophils. This increase in neutrophil-induced cytotoxicity was caused by the addition of an oxidant-dependent mechanism of killing on top of the previously described oxidant-independent pathway. Importantly, the increased susceptibility to injury caused by inhibition of glutathione-dependent reactions was not associated with a reduction in epithelial cell consumption of exogenous H2O2, contrary to the case with catalase. This suggests that there are glutathione-dependent reactions that protect epithelial cells in ways separate from reducing the total burden of exogenous H2O2 on the cells.
Kinetics of Tn5 transposition

Abstract The kinetics of Tn5 transposition and gene expression were studied. For about 2 h after infection with λTn5, Tn5 transpositions accumulate, reaching a level of about 1.5% of the infected cells. After 2 h transposition is essentially turned off. In cells carrying a resident Tn5, transposition is undetectable after infection. The synthesis of the Tn5-specific proteins p58 and p54 and the kanamycin-resistance protein were studied in pre-irradiated cells infected with λTn5. The synthesis of p58 and p54 peaked early after infection and was significantly reduced, relative to p neo , by 2 h after infection. Moreover, p54 appeared to reach a maximum later than p58. These kinetic data put new constraints on models for the regulation of Tn5 transposition.
Differences of ammonia metabolism in symbiotic and aposymbiotic condylactus and cassiopea spp.

Abstract Patterns of the excretion of ammonia in aposymbiotic and symbiotic Condylactus and Cassiopea species suggest that zooxanthellae remove host-produced ammonia. Greater amounts of ammonia are removed by zooxanthellae present in Cassiopea exposed to light whereas symbionts in Condylactus remove larger amounts of ammonia in animals in the dark. The results also indicate that the rate of ammonia production by the animal is affected by light, although there are significant specific differences. It is suggested that the involvement of zooxanthellae in the re-cycling of nitrogen enhances the ecological efficiency of Condylactus and Cassiopea.
Are new agents really making a difference in MDS

Myelodysplastic syndromes (MDS) are a heterogeneous group of bone marrow stem cell disorders characterized by dysplastic hypercellular marrows with peripheral cytopenias. The Leukemia & Lymphoma Society estimates the annual US incidence of MDS is at least 12,000. MDS occurs primarily in people over 60 years old. The pathophysiology of most subtypes of MDS is poorly understood. Treating MDS remains a challenge despite the availability of new agents, such as lenalidomide, azacitidine, and decitabine. Whether these drugs have made a real difference in treating this group of diseases remains controversial.
Breathing pattern in anesthetized chickens: CO2 inhalation and vagotomy.

Abstract 1. 1. The breathing patterns of 20 anesthetized chickens were studied during progressive suppression of intrapulmonary chemoreceptors (IPC) by various concentrations of CO 2 and following bilateral vagotomy. 2. 2. The vagotomy breathing pattern, characterized by a marked accentuation of expiratory times with prolonged expiratory pauses, was markedly different from that induced by CO 2 inhalation. 3. 3. Removal of neural input to the central respiratory centers from IPC does not appear to be solely responsible for the altered breathing pattern following vagotomy in birds.
The effect of co-ordination on the reactivity of aromatic ligands—XI Ligand polarography: 5-nitrosalicylaldehyde

Abstract The polarographic reduction of the nitro and carbonyl groups in 5-nitrosalicylaldehyde has been examined in the free ligand and in its complexes with the alkaline earth and sodium ions. Both of these reductions are irreversible in all the systems examined. The half-wave potentials are effected to only a slight extent by the coordination process. The limiting currents are changed in a fairly regular manner by the gradual increase in the concentration of the added metal ions.
Substantia nigra depigmentation and exposure to encephalitis lethargica.

Objective: Parkinsonism has occasionally been reported as a consequence of infectious diseases. The present study examines the clinical and pathological correlates of parkinsonism across birth cohorts in relation to critical exposure to the encephalitis lethargica epidemic in the early 1900s. Methods: The study population consisted of 678 participants in the Nun Study, of whom 432 died and came to autopsy. Qualitative indices of substantia nigra (SN) depigmentation were verified in a subset of 40 randomly selected subjects using quantitative stereological techniques. SN depigmentation, detected neuropathologically, was correlated with clinical parameters of Parkinson disease, age, and birth cohort. Results: SN depigmentation was detected in 57 (13.2%) of the cohort. Although qualitative SN depigmentation correlated modestly with age (p = 0.02), it correlated best with birth cohort (p = 0.009) for women born in the years 1895–1899. Quantitative measures of SN depigmentation were increased in this birth cohort compared to age matched subjects from flanking birth cohorts 1890–1894 and 1900–1904 (p < 0.001). SN depigmentation correlated with speed of 6- and 50-foot walk (p < 0.0001), up and go test (p < 0.0001), and hand coordination (p < 0.0001). Interpretation: Subjects in the birth cohort 1895–1899 would have been in their late teens and 20s at the onset and during the peak of the encephalitis lethargica epidemic. These were precisely the age ranges of persons who were most often affected by the illness. These data suggest the possibility that the coexistence of parkinsonism and SN depigmentation in this birth cohort may have resulted from the yet undetermined infectious agent responsible for encephalitis lethargica. ANN NEUROL 2012;72:912–917
Field screening in (111)B InAsP/InP strained quantum wells

Low-temperature photoluminescence measurements were performed on InAsP/InP strained quantum wells grown on InP (lll)B substrates by gas-source molecular beam epitaxy. The emission energy was observed to increase as the pump-power density increased. This was attributed to the screening of the internal piezoelectric field by photo-generated carriers. The energy shift was as large as 35 meV for an InAs0.28P0.72/InP quantum well with a lattice mismatch of ~0.9%. A similar structure with a smaller strain showed saturation of the energy shift with increasing pump-power density. We performed a model calculation which includes the quantum confined Stark effect, and this saturation was correlated with a flat-band structure of the quantum well due to the nearly complete screening of the built-in electric field.
The Community Medicine of Cerebrovascular Disease

We now know enough about the incidence rates of cerebrovascular disease in different age groups in the U.S.A. to estimate the number of new cases occurring in mainly white communities in the coming years. Our information on nonwhite incidence is less secure, although rough estimates are possible. Prevalence figures are also known, but give less help in planning future programs. Medical care and hospital programs have given figures which show many deficiencies in our current arrangements for care. A tentative list of risk factors should encourage wider efforts to show whether primary prevention is truly possible. More extensive diagnostic examinations, more specific methods of treatment, and earlier and wider attempts at rehabilitation will improve the fate and quality of existence of future stroke patients. Shorter-trained personnel will help extend good care to a greater proportion of all patients, but not without upsetting some cherished beliefs of health professionals. We should resist the temptation to concentrate on collecting more data, and act now to eradicate neglect from this large problem in community medicine.
Replication of Linkage Studies of Complex Traits: An Examination of Variation in Location Estimates

Summary In linkage studies, independent replication of positive findings is crucial in order to distinguish between true positives and false positives. Recently, the following question has arisen in linkage studies of complex traits: at what distance do we reject the hypothesis that two location estimates in a genomic region represent the same gene? Here we attempt to address this question. Sampling distributions for location estimates were constructed by computer simulation. The conditions for simulation were chosen to reflect features of "typical" complex traits, including incomplete penetrance, phenocopies, and genetic heterogeneity. Our findings, which bear on what is considered a replication in linkage studies of complex traits, suggest that, even with relatively large numbers of multiplex families, chance variation in the location estimate is substantial. In addition, we report evidence that, for the conditions studied here, the standard error of a location estimate is a function of the magnitude of the expected LOD score.
Application of the continuous variation method to cooperative interactions: mechanism of Fe(II)–ferrozine chelation and conditions leading to anomalous binding ratios

The method of continuous variation, often known as the Job plot, has long been used for determining the stoichiometry of two interacting components. The correct binding ratio, n, is generally obtained when the total concentration of the reactants, C(o), is much greater than the dissociation constants involved. For non-cooperative binding systems, the stoichiometry varies between one and n as C(o) increases; whereas for positive cooperative systems, values larger than n may be observed at low C(o). In this report, we present examples to illustrate how the changing apparent stoichiometries as a function of C(o) can provide clues for differentiating various binding mechanisms. To test these concepts, we examined the chelation of Fe(II) with ferrozine in the range of C(o)=7 to 210 microM with Fe(II) expressed in molar concentration or in terms of its binding equivalents (three in this case). The results were analyzed according to several models and found to be most consistent with the mechanism of one-step complex formation or infinite cooperativity with a K(d) of 8 microM.
Pharmacokinetics and bioavailability of a newly synthesized dihydropyridine compound with multidrug resistance reversal activity.

(+/−)3-(3-(4,4-diphenylpiperidin-1-yl)propyl) 5-methyl 4-(3,4-dimethoxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate ((±)-DHP-014), is a new 4-aryl-1,4-dihydropyridine that can reverse multidrug resistance mediated by the ATP-binding cassette (ABC) transport proteins, P-glycoprotein, multidrug resistance-associated protein 1 and breast cancer resistance protein; it exhibits negligible calcium channel blocking activity. The objective of this work was to investigate the pharmacokinetics of this new compound in rats. Three intravenous (1, 2 and 5 mg/kg) and two oral (25 and 50 mg/kg) doses were administered to female Sprague-Dawley rats. A two-compartment model with nonlinear elimination best characterized the pharmacokinetic profiles after intravenous and oral administration in rats. The terminal half-life of (±)-DHP-014 increased and the systemic clearance significantly decreased at higher doses, indicating nonlinear elimination. The dose-dependent clearance is likely due to saturation of metabolism. The apparent volume of distribution of (±)-DHP-014 was 2.0 L/kg in rats and was unchanged with increasing intravenous doses of (±)-DHP-014. The estimated oral bioavailability of (±)-DHP-014 was 8.2%. The poor bioavailability is likely due to the poor solubility of the compound, as well as to substantial first-pass elimination. Copyright © 2005 John Wiley & Sons, Ltd.