cssi/SciSciGPT-SciSciNet huggingface dataset:
Nanomechanics of single-walled carbon nanotubes as composite reinforcement

An analytical nanomechanics model is developed for predicting the elastic self-consistent properties of single-walled carbon nanotube (SWCNT) as composite reinforcement. The molecular structural mechanics is employed to determine the in-plane stiffness and strength of continuous nanotubes in the axial direction of the tube. The effect of tube diameter of the SWCNT on the in-plane stiffness and strength is presented and discussed. The nonlinear stress-strain relationships for defect-free nanotubes have been predicted, which gives an engineering approximation on the ultimate strength and strain to failure of nanotubes. Elastic properties of nanotube composites are further predicted based on a composite micro-mechanics model, using the obtained mechanical properties of nanotubes, volume fraction, and typical polymer matrix properties. Results on the mechanical properties of nanocomposites show that the Young's moduli and strengths of carbon nanotube composites are sensitive to both fiber volume fraction and the tube diameter.
Bifurcations and symmetries of optimal solutions for distributed robotic systems

This paper studies bifurcations and multiple solutions of the optimal control problem for mobile robotic systems. While the existence of multiple local solutions to an optimization problem is not unexpected, the nature of the solutions are such that a relatively rich and interesting structure is present, which potentially could be exploited for controls purposes. In particular, this paper studies a group of unicycle-like autonomous mobile robots operating in a 2-dimensional obstacle-free environment. Each robot has a predefined initial state and final state and the problem is to find the optimal path between two states for every robot. The path is optimized with respect to the control effort and the deviation from a desired formation. The bifurcation parameter is the relative weight given to penalizing the deviation from the desired formation versus control effort. Numerically it is shown that as this number varies, bifurcations of solutions are obtained. Theoretic results of this paper relate to the symmetric properties of these bifurcations and the number and existence of multiple solutions for large and small values of the bifurcation parameter. Understanding the existence and nature of multiple solutions for optimization problems of this type is also of practical importance due to the ubiquity of gradient-based optimization methods where the search method will typically converge to the nearest local optimum.
Mode matching of terahertz radiation to cylindrical wire waveguides using radially symmetric photoconductive antennas

Wire waveguides have recently been shown to be valuable for transporting pulsed terahertz radiation. A radially polarized surface wave is excited when a linearly polarized terahertz pulse is focused on the gap between the wire waveguide and another metal structure. We calculate the input coupling efficiency using a simulation based on the finite element method (FEM). Additional FEM results indicate that enhanced coupling efficiency can be achieved through the use of a radially symmetric photoconductive antenna. Experimental results confirm that such an antenna can generate terahertz radiation which couples to the radial waveguide mode with greatly improved efficiency.
Covariance Statistics of Fully Polarimetric Brightness Temperature Measurements

The covariance statistics of measurements by a fully polarimetric microwave radiometer are derived using a fundamental noise-theoretic approach. Previous published derivations of a similar nature have only included the third Stokes brightness temperature. The results are confirmed by a series of numerical Monte Carlo simulations of the underlying radiometric measurement process. It is found that the additive noise that is present in the measurements can be correlated between polarimetric channels and that the correlation statistics will vary as a function of the polarization state of the scene under observation. General expressions are also derived for the measurement precision (the radiometric NEΔT) and the system noise temperature of the third and fourth Stokes channels. It is found that both the precision and noise temperature can also depend on the polarization state of the scene.
Large Area, High Aspect Ratio Microelectrode Arrays

A method is described for the fabrication of arrays of conducting, high aspect-ratio microwires for use as electrodes. The electrode arrays are fabricated by electrochemical deposition of metals, including Ni, Pt, Ag, Au and Rh, in channel glass templates having parallel, uniform, hollow channels with diameters that range from sub-micrometer to over 100 micrometers. The metals completely fill the hollow channels, yielding highly uniform electrodes with aspect ratios on the order of 1000 or more. The glass template electrically insulates the electrodes from one another. The electrode array wafers are cut and polished to a thickness ranging from about 100 to 2000 micrometers. The overall surface area is as large as 1 square centimeter. Alternatively, the wafers can be partially etched with acid to remove some of the glass matrix surrounding the electrodes, exposing an array of bare, solid wire stubs. The high aspect ratio microelectrode arrays were initially fabricated in order to provide the electrical interface for an intraocular retinal prosthesis, but have additional applications including biological and chemical sensing. Arrays with different channel sizes, different electrode spacing (with pitch from approximately 3R to 20R, where R is the electrode radius), and different geometrical arrangement are presented.
Precipitative polymerization for polycarbonate: A simultaneous reaction–precipitation technique

A novel phenomenon, termed precipitative polymerization, is described. In it, the BPA—phosgene reaction is conducted with simultaneous precipitation of polycarbonate granules. Very low organic-to-aqueous phase ratio and high pH medium are primarily required to cause this in-situ precipitation.
Development and validation of the Indian Adolescent Health Questionnaire.

The period of adolescence is a critical time of development. There is an urgent need to better assess adolescent health worldwide, particularly in India, a country with the world’s largest adolescent population. Validated screening tools are needed to evaluate health-related risks and behaviors in this growing demographic. We developed, validated and administered a school-based health assessment, the Indian Adolescent Health Questionnaire, which can be used as a comprehensive health-screening tool among Indian adolescents in secondary school.
Access control for the SPIN extensible operating system

Summary form only given. In the SPIN operating system (B.N. Bershad et al., 1995; Przemyslaw Pardyak and B.N. Bershad, 1996) built at the University of Washington, we are experimenting with a version of domain and type enforcement (DTE) (L. Badger et al., 1995) that has been extended to address the security concerns of extensible systems. The SPIN operating system defines an extension infrastructure, together with a core set of extensible services, that allows for the fine grained and safe composition of extensions within the operating system kernel. Extensions are written in Modula-3, a type-safe programming language, and execute within the same address space. They interact by calling other parts of the system and by extending existing interfaces to provide new services. A central event dispatcher supports both mechanisms: to call on a service, an extension raises an event, and, to extend an existing interface, an extension registers a handler for that event. The invocation mechanism for events is simply a procedure call, and no context switches are required for the interaction between subsystems (since all extensions are co-located in the same address space).
Scanning monochromatic spatial low-coherence interferometer

A scanning spatial low-coherence interferometer (S-LCI), using an off-axis converging single wavelength laser beam as the probe, resembles a conventional or temporal low-coherence interferometer (T-LCI) in signal formation and data processing. However, the S-LCI is advantageous over a T-LCI with the combination of angle resolving and depth discrimination capabilities. The S-LCI is demonstrated by measuring the angle dependent phase shifts among the multiple reflections of a glass plate, with incident angles accurately scaled in the Fourier domain. The refractive index and geometric thickness of the glass plate are simultaneously produced in this one-step measurement.
Structural Insights into Activation of the Retinal L-type Ca2+ Channel (Cav1.4) by Ca2+-binding Protein 4 (CaBP4)

CaBP4 modulates Ca2+-dependent activity of L-type voltage-gated Ca2+ channels (Cav1.4) in retinal photoreceptor cells. Mg2+ binds to the first and third EF-hands (EF1 and EF3), and Ca2+ binds to EF1, EF3, and EF4 of CaBP4. Here we present NMR structures of CaBP4 in both Mg2+-bound and Ca2+-bound states and model the CaBP4 structural interaction with Cav1.4. CaBP4 contains an unstructured N-terminal region (residues 1–99) and four EF-hands in two separate lobes. The N-lobe consists of EF1 and EF2 in a closed conformation with either Mg2+ or Ca2+ bound at EF1. The C-lobe binds Ca2+ at EF3 and EF4 and exhibits a Ca2+-induced closed-to-open transition like that of calmodulin. Exposed residues in Ca2+-bound CaBP4 (Phe137, Glu168, Leu207, Phe214, Met251, Phe264, and Leu268) make contacts with the IQ motif in Cav1.4, and the Cav1.4 mutant Y1595E strongly impairs binding to CaBP4. We conclude that CaBP4 forms a collapsed structure around the IQ motif in Cav1.4 that we suggest may promote channel activation by disrupting an interaction between IQ and the inhibitor of Ca2+-dependent inactivation domain.
Culture, Communication, and Preferences for Directness in Expression of Directives

Although much research and discussion about culture and communication focuses on the importance of cultural specifics, efforts to theorize in that area tend to begin from apparent universals, and then move to examination of cultural practices as diverse realizations of those universals. This article examines a particular case of cross-cultural theorizing, in regard to preferences for expression of directives. Speakers can opt to express directives, as well as other speech acts, in either a direct or indirect way. A preference for indirect directives has often been assumed in cross-cultural theorizing. Yet a close examination of data from three cultures characterized by a preference for directness in directive pegormance, indicates that culture-specific factors eclipse the universal ones that have been discovered so far. The analysis indicates that cross-cultural theorizing is at least premature, if not in principle impossible. We conclude that preferences for directives are formed within three levels of constraints: praatic differences between direct and indirect forms; social factors made recant in specific instances; and cultural beliefs about personhood, relationships, and the exercise of power.
Evaluating the impact of the American Recovery and Reinvestment Act’s BTOP on broadband adoption

The American Recovery and Reinvestment Act’s Broadband Technology Opportunities Program (BTOP) spent $4.7 billion during 2009–2013 to, inter alia, increase broadband adoption in underserved communities. We characterize the BTOP grants and examine the impact of the awards on broadband adoption. Econometric specifications controlling for award endogeneity related to observed and unobserved county-level factors find that spending is apparently associated with increased broadband adoption. Further investigation, however, reveals that the impacts of spending are nonlinear and even nonmonotonic over the range of county-level BTOP spending in the data. Controlling for trends to reduce the potential for spurious correlation between spending and outcomes removes most of the significance of the results. We conclude with three lessons for policymakers derived from the uncertain outcomes of BTOP spending found in our exploration.
Trading on Culture: Tourism in Formerly Off-Limits Latin America

Keywords: tourism, Peru, Cuba, Nicaragua, Mexico, Latin America, sustainability, economic development
Organic solvent exposure and hearing loss in a cohort of aluminium workers.

Objectives: Organic solvent exposure has been shown to cause hearing loss in animals and humans. Less is known about the risk of hearing loss due to solvent exposures typically found in US industry. The authors performed a retrospective cohort study to examine the relationship between solvent exposure and hearing loss in US aluminium industry workers. Methods: A cohort of 1319 workers aged 35 years or less at inception was followed for 5 years. Linkage of employment, industrial hygiene and audiometric surveillance records allowed for estimation of noise and solvent exposures and hearing loss rates over the study period. Study subjects were classified as “solvent exposed” or not, on the basis of industrial hygiene records linked with individual job histories. High frequency hearing loss was modelled as both a continuous and a dichotomous outcome. Results: Typical solvent exposures involved mixtures of xylene, toluene and/or methyl ethyl ketone (MEK). Recorded solvent exposure levels varied widely both within and between jobs. In a multivariate logistic model, risk factors for high frequency hearing loss included age (OR = 1.06, p = 0.004), hunting or shooting (OR = 1.35, p = 0.049), noisy hobbies (OR = 1.74, p = 0.01), baseline hearing level (OR = 1.04, p Conclusion: These results suggest that occupational exposure to organic solvent mixtures is a risk factor for high frequency hearing loss, although the data do not allow conclusions about dose–response relationships. Industries with solvent-exposed workers should include such workers in hearing conservation programs.
Design and Modeling of a 3-D Magnetic Actuator for Magnetic Microbead Manipulation

This paper presents the design, implementation, modeling, and analyses of a hexapole magnetic actuator that is capable of 3-D manipulation of a magnetic microbead. The magnetic actuator employs six sharp-tipped magnetic poles placed in hexapole configuration, six actuating coils, and a magnetic yoke. The magnetic poles concentrate the magnetic flux generated by the coils to the workspace, resulting in a high magnetic field with a large field gradient for magnetic force generation on the magnetic microbead. A lumped-parameter magnetic force model is then established to characterize nonlinearity of the magnetic force exerting on the magnetic microbead with respect to the applied currents to the coils and the position dependence of the magnetic force in the workspace. The force generation capability of the designed system is then explored using the force model. Moreover, an inverse force model is derived and its effect on the magnetic actuation capability is investigated. The inverse force model facilitates the implementation of a feedback control law to stabilize and control the motion of a magnetic microbead. Experimental results in terms of the magnetic force in relation to stable motion control of a magnetic microbead are used to validate the force model.
Interaction of Nest Predation and Food Limitation in Reproductive Strategies

Heritable reproductive strategies that yield the greatest lifetime production of surviving offspring are favored by natural selection. I consider a reproductive strategy to be the complement of behaviors and traits associated with reproduction that influence lifetime reproductive success. Trade-offs among standard life history traits (e.g., clutch size, growth rate, juvenile and adult mortality) influence success of reproductive strategies (see reviews by Stearns, 1976; Martin, 1987). In addition, energy allocation between reproduction and other activities can influence expression of traits such as clutch size (Cody 1966). However, for organisms that care for their young, success of traits is also strongly affected by the amount of energy and time allocated to care of young by parents (Trivers, 1972, 1974; Low, 1978; Clutton-Brock, 1984). In other words, allocation of energy and time among different activities within reproduction can be as important as allocation between reproduction and other activities.
Lumbar Degenerative Disk Disease: Workup and Conservative Treatment

Low back pain (LBP) is a common complaint, with over 80 % of the population experiencing an episode of LBP during their lives [1]. Recent data from the Centers for Disease Control and Prevention found that 29 % of interviewees had experienced LBP pain at some point during the previous 3 months [2]. Usually, the clinical course is benign and most patients recover within a few months. It has been reported that over 90 % of patients will recover within 3–6 months [1, 3].
Probing off-Hugoniot states in Ta, Cu, and Al to 1000 GPa compression with magnetically driven liner implosions

We report on a new technique for obtaining off-Hugoniot pressure vs. density data for solid metals compressed to extreme pressure by a magnetically driven liner implosion on the Z-machine (Z) at Sandia National Laboratories. In our experiments, the liner comprises inner and outer metal tubes. The inner tube is composed of a sample material (e.g., Ta and Cu) whose compressed state is to be inferred. The outer tube is composed of Al and serves as the current carrying cathode. Another aluminum liner at much larger radius serves as the anode. A shaped current pulse quasi-isentropically compresses the sample as it implodes. The iterative method used to infer pressure vs. density requires two velocity measurements. Photonic Doppler velocimetry probes measure the implosion velocity of the free (inner) surface of the sample material and the explosion velocity of the anode free (outer) surface. These two velocities are used in conjunction with magnetohydrodynamic simulation and mathematical optimization to obtain the current driving the liner implosion, and to infer pressure and density in the sample through maximum compression. This new equation of state calibration technique is illustrated using a simulated experiment with a Cu sample. Monte Carlo uncertainty quantification of synthetic data establishes convergence criteria for experiments. Results are presented from experiments with Al/Ta, Al/Cu, and Al liners. Symmetric liner implosion with quasi-isentropic compression to peak pressure ∼1000 GPa is achieved in all cases. These experiments exhibit unexpectedly softer behavior above 200 GPa, which we conjecture is related to differences in the actual and modeled properties of aluminum.
Challenges in gigapixel multiscale image formation

We present new results from the image formation team on the AWARE Wide-Field project. We will report on new strategies prompted by new challenges encountered in experiments with two prototype AWARE Wide-Field systems.
Microsurgical epididymovasostomy: Predictors of success

AbstractThe results of microsurgical epididymovasostomy for congenital and acquired vasoepididymal obstruction were retrospectively reviewed in 22 patients in an attempt to determine what preoperative or intraoperative factors might predict surgical success. The overall success rate, defined as sperm on postoperative semen analysis, was 48%. The presence of sperm on an intraoperative touch preparation from the epididymis was significantly correlated with response (chi-square 3.24, p <0.10) and no patient without sperm on touch preparation had sperm on subsequent semen analyses. Testicular biopsy positive for spermatogenesis and presence of motile sperm on intraoperative touch preparation were not statistically significant predictors of response. These results suggest that presence or absence of sperm on intraoperative touch preparation is the only significant prognosticator of successful microsurgical epididymovasostomy.
Temporal Pattern and Association Discovery of Diagnosis Codes Using Deep Learning

Longitudinal health records contain data on patients' visits, condition, treatment, and test results representing progression of their health status over time. In poorly understood patient populations, such data are particularly helpful in characterizing disease progression and early detection. In this work we developed a deep learning algorithm for temporal pattern discovery over Rochester Epidemiology Project data. We modeled each patient's records as a matrix of temporal clinical events with ICD9 and HCUP CSS diagnosis codes as rows and years of diagnosis as columns. Patients aged 18 or younger at the time of diagnosis were selected. A deep Boltzmann machine network with three hidden layers was constructed with each patient's diagnosis matrix values as visible nodes. The final weights of the network model were analyzed as the common features among patients' records.
Transplants of NGF-Secreting Fibroblasts Restore Stimulus-Evoked Activity in Barrel Cortex of Basal-Forebrain-Lesioned Rats

Cholinergic nuclei in the basal forebrain supply the cerebral cortex with acetylcholine (ACh). Depletion of cholinergic fibers following basal forebrain lesion results in reduced stimulus-evoked fu...
Ergonomy of Head Mounted Displays Inside Analog Spacesuit - Mars Analog Extravehicular Activities

This paper summarizes an evaluation of commercially available sight peripheral information transparent head-mounted Head-Up Displays (HUD) from the user’s viewpoint during Extra Vehicular Activity (EVA) exploratory tasks in simulated Mars environment. The evaluation is based on experimental use and focuses on the possibilities of safety enhancement, usability regarding visual and voice aid, affordance, usefulness, mission reliability enhancement and HUD health or technical risks. The experiment was performed at the Mars Desert Research Station (MDRS) in Utah. The tested system is composed of two types of commercially available transparent display HUDs (fixed information and head tracking), each providing time, navigation and user heart rate information. The HUDs were used during six one-hour team EVAs, each focused on a navigation tasks and various activities based on the individual EVA goals of the Crew 135 Reliability and Redundancy mission. The experiment data were post-processed/analyzed using video and sound recording by video cameras placed on arms, shoulder, or helmet and embedded in the HUD. Individual feedback is recorded through a modified NASA TLX evaluation system after each EVA, and our conclusions regarding ergonomics are summarized in table form. Hand-held and Head Mounted Displays (HMD) systems are also compared.
Real-time investigations of Pt(111) surface transformations in sulfuric acid solutions.

We present the first broadband sum-frequency generation (SFG) spectra of adlayers from sulfuric acid solutions on Pt(111) surfaces and reveal surface transformations of (bi)sulfate anions in unprecedented detail. SFG amplitudes, bandwidth, and electrochemical Stark tuning of (bi)sulfate vibrational bands centered at 1250−1290 cm−1 strongly depend on the applied potential and are correlated with prominent voltammetric features. (Bi)sulfate adlayers on Pt(111) are important model systems for weak, specific adsorption of anions on catalytically active surfaces. Although the existence of surface transformations on Pt(111) in dilute H2SO4 solutions has been established by previous studies, so far they have not been observed with surface vibrational spectroscopy. Our results confirm previous reports of a surface transformation at 0.21 V and provide new information on a second transformation at 0.5 V due to surface hydroxyl formation and rearrangement of the electric double layer.
Rapid procedure for erythrocyte packed cell volume and sedimentation rate determinations.

SummaryThe conventional erythrocyte sedimentation rate and the packed red cell volume procedures have been modified to effect more than a 50% reduction in the operational time required. The essence...
A Population of the Striped Field Mouse, Apodemus agrarius coreae, in Central Korea

Recent studies of hemorrhagic fever in Korea (Traub et al. , 1954) have indicated the striped field mouse, Apodemus agrarius coreae Thomas, as a possible reservoir of the disease. Sviridenko (1944) considered striped field mice to be of epidemiological importance, since they might be symptomless carriers of several experimentally induced diseases, including encephalitis and tularemia. Since little was known about the ecology or population dynamics of the striped field mouse, it was considered that a study of this and associated species might add to the understanding of possible rodent reservoirs of hemorrhagic fever and other diseases. In January 1954, an area near the present demilitarized zone was selected for study. This area was in the known endemic zone of hemorrhagic fever, and a number of cases had occurred in military units in this region every year since 1951. Late January and early February were devoted to preparing the selected area for a live-trapping program. Actual trapping operations began on February 21 and were continued until July 10. Acknowledgments .—This research was undertaken as a part of the program of the Field Unit, Commission on Hemorrhagic Fever, Armed Forces Epidemiological Board, 11th Evacuation Hospital, APO 301, San Francisco, California. I express my appreciation and sincere thanks to the civilians, officers and enlisted men of the Field Unit who aided considerably in the accomplishment of this study. I am especially indebted to Dr. Marshall Hertig, Director of the Field Unit, whose supervision and encouragement made this research possible, and Mr. Ervin Kardos and 2nd Lt. J. Knox Jones, Jr. for their friendly advice and aid throughout the study. Acknowledgment is also due Lt. Col. Ralph Hollingsworth and 1st Lt. Paul G. Campbell who kindly made available certain necessary facilities; Dr. Chung …
THE CAMBRIDGE ENCYCLOPEDIA OF METEORITES.O. Richard Norton. Cambridge University Press, 2002. Hardbound, 354 p. $50 U.S. METEORITES: A JOURNEY THROUGH SPACE AND TIME. Alex Bevan and John De Laeter. Smithsonian Institution Press, 2002. Hardbound, 215 p.x $35.95 U.S.

Meteorites, like minerals, have become prized collectors’ items. Public interest in meteorites has increased markedly, fueled in large measure by the momentum of scientific discovery over the last several decades. The mineralogy of meteorites has been summarized within a recent MSA Reviews in Mineralogy (Volume 36, Planetary Materials ), but that treatment is too technical for most undergraduate students, non-geologists, and amateur enthusiasts. Two new books, The Cambridge Encyclopedia of Meteorites (henceforth “ CEM ”) and Meteorites: A Journey through Space and Time (henceforth “ MET ”), thoroughly describe extraterrestrial materials with a minimum of required background and jargon, while at the same time providing enough astrophysical and petrologic context to make them exciting. The intended audience for both books is the interested layman, but they are appropriate for undergraduate geology students who seek an introduction to meteorites. Although most of these chunks of rock and iron may not be as visually stunning as colorful, geometric crystals, the ~150 full-color images in both CEM and MET demonstrate why meteorites are so appealing. The vivid photographs alone are worth the price of these books, although the photomicrographs in MET …
Friends or Foes? The Impact of Political Allies and Social Movement Activity on Environmental Legislation in Congress

This paper challenges implications from leading social movement theories of policy change by presenting results that cast doubt on the benefits of having elite allies. Using event history techniques, we show that bill sponsors identified as strong allies of the environmental movement have a significantly lower chance of enacting pro-environmental legislation. Instead, successful legislators had environmental voting records closer to the median voter in Congress, are members of the dominant political party, and hold positions as chairs of environmental committees. While environmental lobbyist groups positively influence the passage of legislation, contrary to conventional wisdom, peaceful protest has no significant effect on legislative outcomes.
Anomalous Luminescence Pressure-Dependence in c-As2S3, a-As2SeS2: Native Defect Structure

The effect of compression on the sub-bandgap energy levels due to native defects in crystalline (c-) AS2S3 and amorphous (a-) As2SeS2 is determined by hydrostatic-pressure photoluminescence (PL) measurements to 108kbar at 13K. The main observation is a rapid decrease of the Stokes shift as the PL-energy, usually (P = 0) at mid-bandgap, becomes more shallow. It is concluded that the PL-defects loosely couple adjacent layers (layer-fragments for the glass) in the ground state, and more tightly bond them in the excited state, thereby affecting a photo-induced local 2d→3d transition.
Agent-Based Wiki Page Simulation: A Conceptual Model

This chapter provides details regarding the development of an agent-based model (ABM) used to understand and analyze editorial changes made to Wiki pages in sites such as Wikipedia and ELATEwiki. The model was structured using a discrete space approach where letters were represented as agents with capabilities that include changing character symbol, deletion, or re-introduction based on rates derived from wiki page histories. Wiki-Hist-Heist, a pre-processor written in C#, was developed to derive information from existing wiki histories and provide model inputs based on detected distributions. The Wiki Page ABM was built using AnyLogic 7.1 which provided user-friendly features and a framework for model organization, experiments, and results. An input form was developed to enable changes to inputs so a variety of pages could be modelled. Overall, this project illustrates the usefulness of AnyLogic 7.1 and its ABM features in this domain. Study limitations and future directions also are described.
The Woodrat Gut Microbiota as an Experimental System for Understanding Microbial Metabolism of Dietary Toxins.

The microbial communities inhabiting the alimentary tracts of mammals, particularly those of herbivores, are estimated to be one of the densest microbial reservoirs on Earth. The significance of these gut microbes in influencing the physiology, ecology and evolution of their hosts is only beginning to be realized. To understand the microbiome of herbivores with a focus on nutritional ecology, while evaluating the roles of host evolution and environment in sculpting microbial diversity, we have developed an experimental system consisting of the microbial communities of several species of herbivorous woodrats (genus Neotoma) that naturally feed on a variety of dietary toxins. We designed this system to investigate the long-standing, but experimentally neglected hypothesis that ingestion of toxic diets by herbivores is facilitated by the gut microbiota. Like several other rodent species, the woodrat stomach has a sacculated, nongastric foregut portion. We have documented a dense and diverse community of microbes in the woodrat foregut, with several genera potentially capable of degrading dietary toxins and/or playing a role in stimulating hepatic detoxification enzymes of the host. The biodiversity of these gut microbes appears to be a function of host evolution, ecological experience and diet, such that dietary toxins increase microbial diversity in hosts with experience with these toxins while novel toxins depress microbial diversity. These microbial communities are critical to the ingestion of a toxic diet as reducing the microbial community with antibiotics impairs the host’s ability to feed on dietary toxins. Furthermore, the detoxification capacity of gut microbes can be transferred from Neotoma both intra and interspecifically to naive animals that lack ecological and evolutionary history with these toxins. In addition to advancing our knowledge of complex host-microbes interactions, this system holds promise for identifying microbes that could be useful in the treatment of diseases in humans and domestic animals.
Radiologic-pathologic correlation of response to chemoradiation in resectable locally advanced NSCLC

Abstract Objectives Accurate assessment of tumor response to chemoradiation has the potential to guide clinical decision-making regarding surgical resection and/or dose escalation for patients. Early assessment has implications for Optimal local therapy for operable locally advanced non-small cell lung cancer (LA-NSCLC) is controversial. This study evaluated quantitative CT-based tumor measurements to predict pathologic response. Materials and methods Patients with operable LA-NSCLC treated with chemoradiation followed by surgical resection were assessed. Tumor diameter and volume were quantified from CT imaging obtained prior to chemoradiation and post-chemoradiation prior to surgical resection. Univariate and multivariate logistic regression were used to determine association with the primary endpoint of pathologic complete response (pCR). Overall survival, locoregional recurrence, and distant metastasis were assessed as secondary endpoints. Results 101 LA-NSCLC patients were identified and treated with preoperative chemoradiation and surgical resection. The median RT dose was 54Gy (range, 46–70) and 98% of patients received concurrent chemoradiation as part of their preoperative treatment. Reduction of CT-defined tumor volume was associated with pCR (OR 1.06 [1.02-1.09], p=0.002) and LRR (HR 1.01 [1.00-1.02], p=0.048). Conventional response assessment determined by RECIST (p=0.213) was not associated with pCR or any secondary endpoints. Conclusion CT-measured reductions in tumor volume after chemoradiation are associated with pCR and provide greater clinical information about tumor response than conventional response assessment (RECIST) or absolute tumor sizes or volumes. This study demonstrates that change in tumor volumes provides better radiologic-pathologic correlation and is thus an additional tool to assess tumor response following chemoradiation.
Beyond Iron: Iridium-Containing P450 Enzymes for Selective Cyclopropanations of Structurally Diverse Alkenes

Enzymes catalyze organic transformations with exquisite levels of selectivity, including chemoselectivity, stereoselectivity, and substrate selectivity, but the types of reactions catalyzed by enzymes are more limited than those of chemical catalysts. Thus, the convergence of chemical catalysis and biocatalysis can enable enzymatic systems to catalyze abiological reactions with high selectivity. Recently, we disclosed artificial enzymes constructed from the apo form of heme proteins and iridium porphyrins that catalyze the insertion of carbenes into a C-H bond. We postulated that the same type of Ir(Me)-PIX enzymes could catalyze the cyclopropanation of a broad range of alkenes with control of multiple modes of selectivity. Here, we report the evolution of artificial enzymes that are highly active and highly stereoselective for the addition of carbenes to a wide range of alkenes. These enzymes catalyze the cyclopropanation of terminal and internal, activated and unactivated, electron-rich and electron-deficient, conjugated and nonconjugated alkenes. In particular, Ir(Me)-PIX enzymes derived from CYP119 catalyze highly enantio- and diastereoselective cyclopropanations of styrene with ±98% ee, >70:1 dr, >75% yield, and ∼10,000 turnovers (TON), as well as 1,2-disubstituted styrenes with up to 99% ee, 35:1 dr, and 54% yield. Moreover, Ir(Me)-PIX enzymes catalyze cyclopropanation of internal, unactivated alkenes with up to 99% stereoselectivity, 76% yield, and 1300 TON. They also catalyze cyclopropanation of natural products with diastereoselectivities that are complementary to those attained with standard transition metal catalysts. Finally, Ir(Me)-PIX P450 variants react with substrate selectivity that is reminiscent of natural enzymes; they react preferentially with less reactive internal alkenes in the presence of more reactive terminal alkenes. Together, the studies reveal the suitability of Ir-containing P450s to combine the broad reactivity and substrate scope of transition metal catalysts with the exquisite selectivity of enzymes, generating catalysts that enable reactions to occur with levels and modes of activity and selectivity previously unattainable with natural enzymes or transition metal complexes alone.
Impact analysis of carbon taxes on the steamcoal and natural gas market in the eastern United States: a linear complementarity model

The impact of a federal excise tax on Appalachian steamcoal on the consumption and production of steamcoal and natural gas is investigated. To examine the comprehensive effects of such taxes, the linear complementarity model is used to ensure consistent results. Predictions on coal and natural gas prices are also made for useful policy implementations.
Human ancestry correlates with language and reveals that race is not an objective genomic classifier

Genetic and archaeological studies have established a sub-Saharan African origin for anatomically modern humans with subsequent migrations out of Africa. Using the largest multi-locus data set known to date, we investigated genetic differentiation of early modern humans, human admixture and migration events, and relationships among ancestries and language groups. We compiled publicly available genome-wide genotype data on 5,966 individuals from 282 global samples, representing 30 primary language families. The best evidence supports 21 ancestries that delineate genetic structure of present-day human populations. Independent of self-identified ethno-linguistic labels, the vast majority (97.3%) of individuals have mixed ancestry, with evidence of multiple ancestries in 96.8% of samples and on all continents. The data indicate that continents, ethno-linguistic groups, races, ethnicities, and individuals all show substantial ancestral heterogeneity. We estimated correlation coefficients ranging from 0.522 to 0.962 between ancestries and language families or branches. Ancestry data support the grouping of Kwadi-Khoe, Kx'a, and Tuu languages, support the exclusion of Omotic languages from the Afroasiatic language family, and do not support the proposed Dene-Yeniseian language family as a genetically valid grouping. Ancestry data yield insight into a deeper past than linguistic data can, while linguistic data provide clarity to ancestry data.
Socrates Ex Situ

ABSTRACTSocrates is an oddity. This past decade has seen both his radical contextualization through archeological efforts to locate him in the public spaces of his native Athens and his radical decontextualization through studies of his reception in later times and places. What unifies those seemingly divergent investigations of Socrates is a fascination with discovering and discerning where Socrates belongs. Socrates’ own contemporaries called him “atopos” (odd, literally, out-of-place), and our contemporary attempts to locate him seem to oppose this displacement, on the one hand, and capitalize upon it, on the other. By seeking Socrates in his own time and place, we may come to understand better how his very movements marked him as out of step with Athenian norms and how such a demarcation affects how we map rhetoric’s borders during that formative time. By seeking Socrates in other times and places, we learn that Socrates himself is a rhetorical topos returned to again and again by people who find or t...
Impact of Moderate Alcohol Discontinuation on Insulin Action and Secretion in Latinos With and Without Hepatitis C.

Background Insulin resistance (IR) is associated with hepatitis C virus (HCV), and Latinos are both at risk of IR and are disproportionately affected by HCV. Moderate alcohol consumption improves insulin sensitivity and may modify HCV-associated IR. We investigated the impact of moderate alcohol discontinuation on insulin sensitivity and secretion in Latinos using direct measurements. Methods Twenty-five nondiabetic, noncirrhotic Latino adults without (n = 17) or with (n = 8) HCV underwent 3-day metabolic assessment before and after prescription of 6 weeks of moderate alcohol discontinuation. Peripheral IR was measured via steady-state plasma glucose (SSPG) and hepatic IR using endogenous glucose production during a 2-step 240-minute insulin suppression test. Insulin secretion was measured using graded glucose infusion test. Results Baseline mean age was 46 ± 11 years, 63% male, 29% had HCV, and mean body mass index was 27 ± 4 kg/m2 . Compared to non-HCV, HCV patients had a higher median SSPG (132 vs. 98.8 mg/dl, p = 1.0), hepatic IR (13.5 vs. 11.3, p = 0.24), and insulin secretion rate (ISR-AUC, 1,290 vs. 1,250 pmol/min, p = 0.98). After confirmed alcohol discontinuation, hepatic IR was the only parameter that changed significantly (increased, mean change 2.6 ± 4.8, p = 0.02). Higher baseline alanine aminotransferase (ALT) was also associated with a greater change in hepatic IR (average 4.0 points/ALT doubling, p = 0.004), and HCV was associated with a lesser change (average -7.3 points, p = 0.002), independent of ALT. Conclusions Short-term moderate alcohol discontinuation adversely impacted hepatic IR in Latinos which was influenced by level of ALT at baseline independent of etiology. Although reduction in ALT through weight loss and HCV eradication remains a priority in improving IR, the observed nonharmful effect of moderate alcohol use represents a potentially confounding variable that warrants further study.
The Family Dog: Influence of Parents on Children’s Concepts of Responsible Dog Care

Dog ownership is often imagined as a quintessential part of a childhood. Approximately half of households in the United States and one fourth in the European Union are home to one or more dogs. The majority of the families who acquire dogs do so, at least in part, because they believe dog ownership will teach children responsibility. Yet it is the role modeling and teaching of responsibility that adults provide to children, rather than mere ownership of a dog, that shapes children’s attitudes, values, and beliefs about responsible care. Furthermore, parents’ childhood experiences with dogs, as well as the ways in which they interact with their children in caring for family dogs, influence children’s thinking. This chapter describes parents’ views of responsible dog care and ownership and explores how those perspectives might influence children’s concepts of responsible care. Findings are based on an Eastern United States mixed-methods study involving 51 children and 46 adults. Data include interviews with children between the ages of 4 and 14 and their parents’/guardians’ responses to a questionnaire that included both forced choice and open-ended items. Major sections of the survey included the value parents place on dogs, concepts and practices of responsible dog care, reasons for relinquishing a dog, their childhood experience with dogs, and their perceptions of their child’s understanding of safe behaviors around dogs.
A Fully Human Antagonist Anti-CD40 Antibody Triggers Significant Antitumor Activity Against Human Multiple Myeloma.

We previously demonstrated that CHIR-12.12, a fully human anti-CD40 mAb (IgG1) generated in XenoMouseO mice (Abgenix, Inc), blocks CD40/CD40 ligand (CD40L) interactions and has more potent anti-lymphoma activity than Rituximab both in vivo and in vitro (abstract #2386, ASH, San Diego, Dec. 2003). In this study, we assess the efficacy of CHIR-12.12 against human multiple myeloma (MM) using CD40-expressing MM cell lines and purified CD138+ patient cells. CHIR-12.12 binds to purified CD138+ MM cells in >80% (10/12) of patient samples, as measured by flow cytometry: the mean fluorescence intensity (MFI) range was 1 to 20 for CHIR-12.12 vs 0.2–0.9 for control human IgG1. We next examined the antagonist activity of CHIR-12.12 in MM cells. CHIR-12.12 blocked CD40L-mediated proliferation of CD40-expressing MM lines and purified CD138+ patient cells from 2 MM patients in a dose-response manner. In contrast, CHIR-12.12 alone did not alter constitutive MM cell proliferation. Immunoblotting analysis demonstrated that PI3-K/AKT, NF-kB, and ERK activation induced by hCD40L in the 12BM MM cell line was significantly inhibited by CHIR-12.12 (5 μg/ml). Adhesion of MM cells to bone marrow stromal cells (BMSCs) confers growth and survival benefit for tumor cells. Since CD40 activation, either by stimulatory mouse anti-CD40 mAb G28.5 or formaldehyde-fixed CHO cells expressing hCD40L, induces MM cell adhesion to fibronectin (FN) or BMSCs, we next asked whether antagonist CHI12.12 abrogates this process. CHIR-12.12 inhibited CD40L-induced adhesion of MM cell lines to FN in a dose dependent manner (0.001-10 μg/ml), whereas control human IgG did not. Moreover, CHIR-12.12 (1 μg/ml) blocked hCD40L-induced adhesion of freshly isolated patient MM cells to BMSCs. Adhesion of MM cells to BMSCs induces IL-6 secretion, an important growth and survival cytokine for MM cells, and treatment of MM cells with hCD40L further augmented adhesion-induced IL-6 secretion. Conversely, pretreatment of CD40-expressing MM cell lines with CHIR-12.12 significantly decreased IL-6 secretion triggered by coculture of MM cells with BMSCs. We next examined whether CHIR-12.12 stimulates antibody-dependent cellular cytotoxicity (ADCC) against CD40-expressing MM cells. Human peripheral blood mononuclear cells and purified NK cells (CD56+CD3−) were used as effector cells. CHIR-12.12 triggered MM cell lysis in a dose dependent manner, as measured in CD40-expressing MM cell lines. The maximum specific lysis of 20–70 % was achieved at 10 μg/ml concentration of CHIR-12.12. CHIR-12.12 mediated lysis was specific to CD40-expressing MM cells, as CHIR-12.12 did not induce ADCC against CD40-negative MM cells. Importantly, CHIR-12.12 induced ADCC against CD138+ cells isolated from 2 MM patients. These results provide preclinical rationale for clinical evaluation of CHIR-12.12 with the goal of improving patient outcome in MM.