cssi/SciSciGPT-SciSciNet huggingface dataset:
Fractional branes and boundary states in orbifold theories

We study the D-brane spectrum of = 2 string orbifold theories using the boundary state formalism. The construction is carried out for orbifolds with isolated singularities, non-isolated singularities and orbifolds with discrete torsion. Our results agree with the corresponding K-theoretic predictions when they are available and generalize them when they are not. This suggests that the classification of boundary states provides a sort of ``quantum K-theory'' just as chiral rings in CFT provide ``quantum'' generalizations of cohomology. We discuss the identification of these states with D-branes wrapping holomorphic cycles in the large radius limit of the CFT moduli space. The example 3/3 is worked out in full detail using local mirror symmetry techniques. We find a precise correspondence between fractional branes at the orbifold point and configurations of D-branes described by vector bundles on the exceptional 2 cycle.
Constraints on cosmic strings due to black holes formed from collapsed cosmic string loops

The cosmological features of primordial black holes formed from collapsed cosmic string loops are studied. Observational restrictions on a population of primordial black holes are used to restrict f, the fraction of cosmic string loops which collapse to form black holes, and mu, the cosmic string mass-per-unit length. Using a realistic model of cosmic strings, we find the strongest restriction on the parameters f and mu is due to the energy density in 100MeV photons radiated by the black holes. We also find that inert black hole remnants cannot serve as the dark matter. If earlier, crude estimates of f are reliable, our results severely restrict mu, and therefore limit the viability of the cosmic string large-scale structure scenario.
Magnetic nanoparticles for the manipulation of proteins and cells

In the rapidly developing areas of nanobiotechnology, magnetic nanoparticles (MNPs) are one type of the most well-established nanomaterials because of their biocompatibility and the potential applications as alternative contrast enhancing agents for magnetic resonance imaging (MRI). While the development of MNPs as alternative contrast agents for MRI application has moved quickly to testing in animal models and clinical trials, other applications of biofunctional MNPs have been explored extensively at the stage of qualitative or conceptual demonstration. In this critical review, we summarize the development of two straightforward applications of biofunctional MNPs—manipulating proteins and manipulating cells—in the last five years or so and hope to provide a relatively comprehensive assessment that may help the future developments. Specifically, we start with the examination of the strategy for the surface functionalization of MNPs because the applications of MNPs essentially depend on the molecular interactions between the functional molecules on the MNPs and the intended biological targets. Then, we discuss the use of MNPs for manipulating proteins since protein interactions are critical for biological functions. Afterwards, we evaluate the development of the use of MNPs to manipulate cells because the response of MNPs to a magnetic field offers a unique way to modulate cellular behavior in a non-contact or “remote” mode (i.e. the magnet exerts force on the cells without direct contact). Finally, we provide a perspective on the future directions and challenges in the development of MNPs for these two applications. By reviewing the examples of the design and applications of biofunctional MNPs, we hope that this article will provide a reference point for the future development of MNPs that address the present challenges and lead to new opportunities in nanomedicine and nanobiotechnology (137 references).
Focus article report of the NIH task force on research standards for chronic low back pain

Background Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients' lives. Such cLBP is often termed non-specific and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. Methods The NIH Pain Consortium therefore charged a Research Task Force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel developed a 3-stage process, each with a 2-day meeting. Results The panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimum dataset to describe research participants (drawing heavily on the PROMIS methodology); reporting "responder analyses" in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved the recommendations, which investigators should incorporate into NIH grant proposals. Conclusions The RTF believes these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of chronic low back pain. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes. We expect that the RTF recommendations will become a dynamic document and undergo continual improvement.
Two-photon absorption laser-induced fluorescence of atomic nitrogen by an alternative excitation scheme

Abstract A two-photon absorption laser-induced fluorescence (TALIF) scheme to monitor ground-state atomic nitrogen is described. Excitation at 207 nm to the (3p) 4 S° 3/2 upper state is demonstrated to be superior to the traditional 211 nm excitation to (3p) 4 D° 7/2 . Most striking is the low quenching rate of the upper (3p) 4 S° 3/2 state by N 2 at k q =6.7(9)×10 −11 cm 3 s −1 , nearly an order of magnitude lower than the traditional technique. The two-photon excitation rate at 207 nm is also measured to be a factor of 3.5 greater than the traditional scheme. The results suggest that the 207 nm excitation scheme should be employed in future N-atom diagnostic work.
A labor income-based measure of the value of human capital: An application to the states of the United States

Abstract We argue that a sensible measure of the aggregate value of human capital is the ratio of total labor income per capita to the wage of a person with zero years of schooling. The reason is that total labor income not only incorporates human capital but also physical capital: given human capital regions with higher physical capital will tend to have higher wages for all workers and, therefore, higher labor income. We find that one way to net out the effect of aggregate physical capital on labor income is to divide labor income by the wage of a zero-schooling worker. For the average U.S. state, our measure suggests that the value of human capital during the 1980s grew at a much larger rate than schooling. The reason has to do with movements in the relative productivities of the different workers: in some sense, some workers and some types of schooling became more relevant in the 1980s and, as a result, measured human capital increased.
The ultrastructure of the basilar membrane in the cat.

A detailed study of the feline basilar membrane was performed in 13 cochleae with light microscopy and in six with electron microscopy. The distribution of the mesothelial cells and homogeneous ground substance with the filaments was recorded and plotted as a function of length along the cochlear duct. The width, thickness and number of filaments were also measured. In the lower basal turn the basilar membrane was narrowest and its entire thickness was occupied by filaments. In the apical region the width was maximal and the filaments were fewer. The density of the filaments counted in the bundles showed no significant difference along the cochlear duct or across the width of the basilar membrane, but the number of filaments decreased markedly (approximately a tenfold difference) from base to apex. The number of mesothelial cells increased towards the apex. These morphological characteristics may be related to the different motion pattern of the basilar membrane along the length of the cochlear duct. A di...
Fast BEM solution for coupled 3D electrostatic and linear elastic problems

Abstract This paper presents the development of a fast Boundary Element Method solver for 3D linear elasticity utilizing the precorrected-FFT and parallel computing. The purpose of this work is to develop mesh-consistent coupled BEM solvers to facilitate the solution of complex coupled mechanical–electrostatic, magnetic, or fluidic problems common in the design of Micro- and Nano-Mechanical Systems. ‘Mesh-consistent’ meaning that all analyses would rely on the same basic mesh, eliminating the difficulties involved in translating results from one model to another.
Basic Hytran Simulation Language: BHSL

An appropriate subtitle for this paper might read: "A Fortran Compatible Dialect of the SCI Continuous System Simulation Language." Here the words "continuous system" distinguish the application area of interest from that encompassed by the event based simulation languages of the genre of GPSS, SIMSCRIPT, etc. The reference to SCI indicates that BHSL, while certainly a member of the growing family of simulation languages, was designed to meet standardization guidelines established by the Simulation Software Committee of Simulation Councils Incorporated.
Fiber–Matrix Interfacial Characteristics in a Fiber‐Reinforced Ceramic‐Matrix Composite

Fiber—matrix interfacial shear stress and mechanical properties in zirconmatrix composites uniaxially re-inforced with either uncoated or BN-coated silicon carbide filaments were measured in the as-fabricated state and after a thermal treatment at 1300°C for 100 h. All the tested composites showed higher fiber—matrix interfacial debond stress than frictional stress and toughened-composite behavior. Mechanical properties of composites reinforced with uncoated filaments were unaffected by an annealing treatment at 1300°C for 100 h. In contrast, an identical annealing treatment given to a composite reinforced with BN-coated filaments led to a decrease in first matrix cracking stress and ultimate strength. These observations were related to the changes in the measured interfacial shear stress values as a result of the annealing treatment.
Mining metadata for composability of IPs from SystemC IP library

Exploring the design space when constructing a system is vital to realize a well performing design. Design complexity has made building high-level system models to explore the design space an essential but time-consuming and tedious part of the system design. Reduction in design time and acceleration of design exploration can be provided through reusing IP-cores to construct system models. As a result, it is common to have high-level SoC design flow based on IP libraries promoting reuse. However, the success of these would be dependent on how introspection and reflection capabilities are provided as well as what are the interoperability standard defined. This leads to the important question of what kind of IP metadata must be available to allow CAD tools to effectively manipulate these designs as well as allow for a seamless integration and exchange design information between tools and design flows. In this article, we describe our tools and methodology, which allow introspection of SystemC designs, such that the extracted metadata enables IP composition. We discuss the issues related to extraction of metadata from IPs specified in SystemC and show how our methodology combines C++ and XML parsers and data structures to achieve the above.
Stalking the wily hacker

An astronomer-turned-sleuth traces a German trespasser on our military networks, who slipped through operating system security holes and browsed through sensitive databases. Was it espionage?
Multi‐rate nonlinear state and parameter estimation in a bioreactor

This paper concerns real-time, multi-rate, nonlinear state and parameter estimation in a pilot-scale biochemical reactor in which cultivation of mouse-mouse hybridoma cells takes place. A multi-rate estimator is designed and implemented to estimate specific growth rate and concentrations of viable cells, total cells, glucose, glutamine, and monoclonal antibodies (MAb) in the reactor. These are estimated from frequent measurement (inferred values) of oxygen uptake rate (OUR) and infrequent and delayed measurements of the concentrations of viable cells, total cells, glucose, glutamine, and MAb. The infrequent measurements are available every 2 to 17 h with a time delay of 0.08 to 2.00 h, and OUR is inferred from dissolved oxygen concentration measurements that are available very 0.17 h. For each of the process variables, its infrequent measurement data and the profile of its estimate are presented to show the performance of the multi-rate estimator.
Microstructure Analysis and Stress‐Strain Behavior of a Model Refractory System MgO‐CaMgSiO4

The effects of a silicate boundary phase on the high-temperature stress-strain behavior of MgO materials have been studied using a model system MgO-CaMgSiO4 (monticellite, CMS). Specimens were fabricated by hot-pressing, or by hot-pressing and annealing, and contained up to 15% silicate phase. The boundary phase consisted primarily of CMS. The stress-strain behavior of these specimens in the range 1200° to 1400°C was strongly dependent on the degree of continuity of the grain boundary phase and on the temperature.
Reduced-latency SC polar decoder architectures

Polar codes have become one of the most favorable capacity achieving error correction codes (ECC) along with their simple encoding method. However, among the very few prior successive cancellation (SC) polar decoder designs, the required long code length makes the decoding latency high. In this paper, conventional decoding algorithm is transformed with look-ahead techniques. This reduces the decoding latency by 50%. With pipelining and parallel processing schemes, a parallel SC polar decoder is proposed. Sub-structure sharing approach is employed to design the merged processing element (PE). Moreover, inspired by the real FFT architecture, this paper presents a novel input generating circuit (ICG) block that can generate additional input signals for merged PEs on-the-fly. Gate-level analysis has demonstrated that the proposed design shows advantages of 50% decoding latency and twice throughput over the conventional one with similar hardware cost.
The epidemiology of aerobic dance injuries

Aerobic dance is currently the largest organized fitness activity primarily for women in the United States. In an attempt to identify and characterize the health problems associated with it, 351 students and 60 instructors from six facilities were followed for 16 weeks with weekly telephone calls. Of the 327 medical complaints reported during 29,924 hours of documented activity, only 84 (0.28 per hundred hours) resulted in any disa bility and only 2.1% required medical care. The shin/ leg, foot and ankle accounted for nearly two-thirds of the injuries. Instructors were twice as likely to be injured as students. Both a history of prior orthopaedic prob lems and a lack of involvement in other fitness activities resulted in higher injury rates. Injury rates were influ enced by the design and conduct of the aerobic pro gram but not by brand of shoe or type of flooring. Aerobic dance appears to offer students the potential for fitness enhancement with a minimal risk of injury.
Comparison of Graph Generation Methods for Structural Complexity Based Assembly Time Estimation

This paper compares two different methods of graph generation for input into the complexity connectivity method to estimate the assembly time of a product. The complexity connectivity method builds predictive models for assembly time based on twenty-nine complexity metrics applied to the product graphs. Previously the part connection graph was manually created, but recently the Assembly Mate Method and the Interference Detection Method have introduced new automated tools for creating the part connectivity graphs. These graph generation methods are compared on their ability to predict the assembly time of multiple products. For this research, eleven consumers products are used to train an artificial neural network and three products are reserved for testing. The results indicate that both the Assembly Mate Method and the Interference Detection Method can create connectivity graphs that predict the assembly time of a product to within 45% of the target time. The Interference Detection Method showed less variability than the Assembly Mate Method in the time estimations. The Assembly Mate Method is limited to only SolidWorks assembly files, while the Interference Detection Method is more flexible and can operate on different file formats including IGES, STEP, and Parasolid. Overall, both of the graph generation methods provide a suitable automated tool to form the connectivity graph, but the Interference Detection Method provides less variance in predicting the assembly time and is more flexible in terms of file types that can be used.
A note on modeling aggregate productivity growth: The importance of imperfect markets*

Models of aggregate productivity growth linked to sectoral models of production typically assume that product and factor markets are perfectly competitive. The perfect markets assumption allows intermediate goods to be viewed as internal, offsetting transfers. This paper relaxes the conventional perfect markets assumption. The alternatives of basing aggregate models of productivity growth on value-added versus delivery-to-final-demand frameworks are analyzed. The important finding is that if imperfect markets exist, then the value-added and the delivery-to-final-demand models generate identical measures of aggregate productivity growth only under very restrictive assumptions; moreover, a simple variant of imperfect competition cannot reconcile these productivity measures.
Perturbative gluon resummation of the top quark production cross-section

Abstract We present a calculation of the total cross section for top quark production based on a new perturbative resummation of gluon radiative corrections to the basic QCD subprocesses. We use Principal Value Resummation to calculate all relevant large threshold corrections. Advantages of this method include its independence from arbitrary infrared cutoffs and specification of the perturbative regime of applicability. For p p collisions at center-of-mass energy s =1.8 TeV and a top mass of 175 GeV, we compute σ(t t ) = 5.52 −0.45 +0.07 pb.
Present status of automatic ellipsometers

Abstract Operating principles and capabilities of presently-built automatic ellipsometers are reviwed. The instruments are classified according to their optical principles of operation and their capabilities are compared on the basis of uniform performance criteria. Possible future developments are indicated.
Single Electron Transfer in Michael Induced Ring Closure reactions

Abstract Substituted cyclopropyl ether 3 is readily available from γ-bromoalkylidene malonate 2 via a Michael Induced Ring Closure (MIRC) reaction with sodium methoxide. Single Electron Transfer mechanism is suggested for the key cyclization step to account for the observed high reactivity of a tertiary halide, phosphonium salt and nitro compound.
Two-Phase Microfluidics for Semiconductor Circuits and Fuel Cells

Industrial trends are presenting major challenges and opportunities for research on two-phase flows in microchannels. Semiconductor companies are developing 3D circuits for which multilevel microfluidic cooling is important. Gas delivery microchannels are promising for PEM fuel cells in portable electronics. However, data and modeling are needed for flow regime stability, liquid entrainment/clogging, and bubble inception/departure in complex 2D and 3D geometries. This paper provides an overview of the Stanford two-phase microfluidics program, with a focus on recent experimental and theoretical progress. Microfabrication technologies are used to distribute heaters, thermometers, pressure sensors, and liquid injection ports along the flow path. Liquid PIV quantifies forces on bubbles, and fluorescence imaging detects flow shapes and liquid volume fraction. Separated flow models account for conjugate conduction, liquid injection, evaporation, and a variety of flow regimes. This work benefits strongly from in...
Algorithms for implicit hitting set problems

A hitting set for a collection of sets is a set that has a non-empty intersection with each set in the collection; the hitting set problem is to find a hitting set of minimum cardinality. Motivated by instances of the hitting set problem where the number of sets to be hit is large, we introduce the notion of implicit hitting set problems. In an implicit hitting set problem the collection of sets to be hit is typically too large to list explicitly; instead, an oracle is provided which, given a set H, either determines that H is a hitting set or returns a set that H does not hit. We show a number of examples of classic implicit hitting set problems, and give a generic algorithm for solving such problems optimally. The main contribution of this paper is to show that this framework is valuable in developing approximation algorithms. We illustrate this methodology by presenting a simple on-line algorithm for the minimum feedback vertex set problem on random graphs. In particular our algorithm gives a feedback vertex set of size n - (1/p) log np(1 - o(1)) with probability at least 3/4 for the random graph Gn,p (the smallest feedback vertex set is of size n - (2/p) log np(1 + o(1))). We also consider a planted model for the feedback vertex set in directed random graphs. Here we show that a hitting set for a polynomial-sized subset of cycles is a hitting set for the planted random graph and this allows us to exactly recover the planted feedback vertex set.
Discovering Attribute Shades of Meaning with the Crowd

To learn semantic attributes, existing methods typically train one discriminative model for each word in a vocabulary of nameable properties. However, this "one model per word" assumption is problematic: while a word might have a precise linguistic definition, it need not have a precise visual definition. We propose to discover shades of attribute meaning. Given an attribute name, we use crowdsourced image labels to discover the latent factors underlying how different annotators perceive the named concept. We show that structure in those latent factors helps reveal shades, that is, interpretations for the attribute shared by some group of annotators. Using these shades, we train classifiers to capture the primary (often subtle) variants of the attribute. The resulting models are both semantic and visually precise. By catering to users' interpretations, they improve attribute prediction accuracy on novel images. Shades also enable more successful attribute-based image search, by providing robust personalized models for retrieving multi-attribute query results. They are widely applicable to tasks that involve describing visual content, such as zero-shot category learning and organization of photo collections.
Chordal Loewner families and univalent Cauchy transforms

We study chordal Loewner families in the upper half-plane and show that they have a parametric representation. We show one, that to every chordal Loewner family there corresponds a unique measurable family of probability measures on the real line, and two, that to every measurable family of probability measures on the real line there corresponds a unique chordal Loewner family. In both cases the correspondence is being given by solving the chordal Loewner equation. We use this to show that any probability measure on the real line with finite variance and mean zero has univalent Cauchy transform if and only if it belongs to some chordal Loewner family. If the probability measure has compact support we give two further necessary and sufficient conditions for the univalence of the Cauchy transform, the first in terms of the transfinite diameter of the complement of the image domain of the reciprocal Cauchy transform, and the second in terms of moment inequalities corresponding to the Grunsky inequalities.
J-Resolved He I Emission Predictions in the Low-Density Limit

Determinations of the primordial helium abundance are used in precision cosmological tests. These require highly accurate He I recombination rate coefficients. Here we reconsider the formation of He I recombination lines in the low-density limit. This is the simplest case, and it forms the basis for the more complex situation in which collisions are important. The formation of a recombination line is a two-step process, beginning with the capture of a continuum electron into a bound state and followed by radiative cascade to ground. The rate coefficient for capture from the continuum is obtained from photoionization cross sections and detailed balancing, while radiative transition probabilities determine the cascades. We have made every effort to use today's best atomic data. Radiative decay rates are from Drake's variational calculations, which include QED, fine structure, and singlet-triplet mixing. Certain high-L fine-structure levels do not have a singlet-triplet distinction, and the singlets and triplets are free to mix in dipole-allowed radiative decays. We use quantum-defect or hydrogenic approximations to include levels higher than those treated in the variational calculations. Photoionization cross sections come from R-matrix calculations when possible. We use Seaton's method to extrapolate along sequences of transition probabilities to obtain threshold photoionization cross sections for some levels. For higher n we use scaled hydrogenic theory or an extension of quantum-defect theory. We create two independent numerical implementations to ensure that the complex bookkeeping is correct. The two codes use different (reasonable) approximations to span the gap between lower levels, having accurate data, and high levels, where scaled hydrogenic theory is appropriate. We also use different (reasonable) methods to account for recombinations above the highest levels individually considered. We compare these independent predictions to estimate the uncertainties introduced by the various approximations. Singlet-triplet mixing has little effect on the observed spectrum. While intensities of lines within multiplets change, the entire multiplet, the quantity normally observed, does not. The lack of high-precision photoionization cross sections at intermediate n and low L introduces ~0.5% uncertainties in intensities of some lines. The high-n unmodeled levels introduce ~1% uncertainties for "yrast" lines, defined as those having L = n - 1 upper levels. This last uncertainty will not be present in actual nebulae, since such high levels are held in statistical equilibrium by collisional processes. We identify those lines that are least affected by uncertainties in the atomic physics and so should be used in precision helium abundance determinations.
EVALUATION OF THE CARCINOGENIC RISK OF BIOCHEMICALLY INERT INSOLUBLE PARTICLES BY THE EPA USING RAT INHALATION DATA

Regulations pertaining to inhalable particulate matter are promulgated primarily by three program offices of the U.S. Environmental Protection Agency (EPA): Pollution Prevention and Toxic Substances (OPPTS), Air Quality Planning and Standards (OAQPS), and Mobile Sources (OMS). Risk assessment for these agents are carried out either by the program offices or by the National Center for Environmental Assessment (NCEA), formerly the Office of Health and Environmental Assessment (OHEA). Particular matter pollutants within the regulatory domain of OAQPS for which either quantitative or qualitative assessment of cancer risk has been carried out include asbestos, beryllium, cadmium, nickel refinery dust, nickel subsulfide, and ambient particulate matter of less than 10 µm diameter (PM10). OPPTS has qualitatively evaluated manmade mineral fibers, titanium dioxide, and vermiculite. Asbestos is the only fiber for which cancer quantitation has been carried out. For several of these agents, risk is based upon human da...
Computation of Yukawa couplings for Calabi-Yau hypersurfaces in weighted projective spaces

Abstract B.R. Greene, D.R. Morrison and M.R. Plesser [Mirror Manifolds in Higher Dimension, CLNS-93/1253, IASSNS-HEP-94-2, YCTP-92] have recently suggested a general method for constructing a mirror map between a d -dimensional Calabi-Yau hypersurface and its mirror partner for d > 3. We apply their method to smooth hypersurfaces in weighted projective spaces and compute the Chern numbers of holomorphic curves on these hypersurfaces. As anticipated, the results satisfy nontrivial integrality constraints. These examples differ from those studied previously in that standard methods of algebraic geometry which work in the ordinary projective space case for low degree curves are not generally applicable. In the limited special cases in which they do work we can get independent predictions, and we find agreement with our results.
Risks and Incentives in Underserved Mortgage Markets

Abstract Subsidized loans may help increase home ownership in low income neighborhoods with positive social benefits; however, there are risks and costs to the homeowners themselves. Home ownership increases incentives to maintain property and neighborhood, as well as decreasing the outflow of rents from low-income zones. These benefits however are not costless to participants. With a mortgage comes the possibility of a default, the financial demands of maintenance, the reduction in alternate investment opportunities, an increased exposure to fluctuations in local economic conditions, and a drastic reduction in the liquidity of personal wealth. In this paper, we examine the role of the owner-occupied house in the asset allocation decision of a family living in an area characterized as a low income neighborhood. We find that the current subsidies are likely to be too low relative to the costs. In particular, the tax law makes home ownership relatively less attractive to low-income families. This may explain a lack of home ownership and, thus, mortgage lending in low-income neighborhoods.
Deoxygenation of polyhydroxybenzenes: an alternative strategy for the benzene-free synthesis of aromatic chemicals.

New synthetic connections have been established between glucose and aromatic chemicals such as pyrogallol, hydroquinone, and resorcinol. The centerpiece of this approach is the removal of one oxygen atom from 1,2,3,4-tetrahydroxybenzene, hydroxyhydroquinone, and phloroglucinol methyl ether to form pyrogallol, hydroquinone, and resorcinol, respectively. Deoxygenations are accomplished by Rh-catalyzed hydrogenation of the starting polyhydroxybenzenes followed by acid-catalyzed dehydration of putative dihydro intermediates. Pyrogallol synthesis consists of converting glucose into myo-inositol, oxidation to myo-2-inosose, dehydration to 1,2,3,4-tetrahydroxybenzene, and deoxygenation to form pyrogallol. Synthesis of pyrogallol via myo-2-inosose requires 4 enzyme-catalyzed and 2 chemical steps. For comparison, synthesis of pyrogallol from glucose via gallic acid intermediacy and the shikimate pathway requires at least 20 enzyme-catalyzed steps. A new benzene-free synthesis of hydroquinone employs conversion of ...
Ames hypopituitary dwarf mice demonstrate imbalanced myelopoiesis between bone marrow and spleen.

Ames hypopituitary dwarf mice are deficient in growth hormone, thyroid-stimulating hormone, and prolactin. The phenotype of these mice demonstrates irregularities in the immune system with skewing of the normal cytokine milieu towards a more anti-inflammatory environment. However, the hematopoietic stem and progenitor cell composition of the bone marrow (BM) and spleen in Ames dwarf mice has not been well characterized. We found that there was a significant decrease in overall cell count when comparing the BM and spleen of 4–5 month old dwarf mice to their littermate controls. Upon adjusting counts to differences in body weight between the dwarf and control mice, the number of granulocyte-macrophage progenitors, confirmed by immunophenotyping and colony-formation assay was increased in the BM. In contrast, the numbers of all myeloid progenitor populations in the spleen were greatly reduced, as confirmed by colony-formation assays. This suggests that there is a shift of myelopoiesis from the spleen to the BM of Ames dwarf mice; however, this shift does not appear to involve erythropoiesis. The reasons for this unusual shift in spleen to marrow hematopoiesis in Ames dwarf mice are yet to be determined but may relate to the decreased hormone levels in these mice.
A Two-Dimensional Position-Sensitive Detector for Thermal Neutrons

We have developed and tested a thermal neutron, two-dimensional position-sensitive detector for use in neutron scattering from biological samples. The detector is based on a multi-wire proportional concept with a gas filling of 6 atmos. He3, 4 atmos. A, and 0.5 atmos. CO2. The position readout uses a resistive wire with charge division to determine position. We have measured a resolution of less than 3 mm (EWHM) with a detection efficiency of 70% at 2.8 A neutrons. Considerations leading to an optimal configuration are discussed.
Rationality of motivic zeta functions for curves with finite abelian group actions

Let VarkG denote the category of pairs (X,σ), where X is a variety over k and σ is a group action on X. We define the Grothendieck ring for varieties with group actions as the free abelian group of isomorphism classes in the category VarkG modulo a cutting and pasting relation. The multiplication in this ring is defined by the fiber product of varieties. This allows for motivic zeta-functions for varieties with group actions to be defined. This is a formal power series ∑n=0∞[Symn(X,σ)]tn with coefficients in the Grothendieck ring. The main result of this paper asserts that the motivic zeta-function for an algebraic curve with a finite abelian group action is rational. This is a partial generalization of Weil’s First Conjecture.
A variable stability projectile using an internal moving mass

AbstractWeapon designers have known for some time that projectiles with low static margin have proven to be more susceptible to launch perturbations than comparable projectiles with high static stability, and that low static margin allows greater control authority. The work reported here examines a mechanism for active static margin control in flight through mass centre modification, demonstrating that such a system has significant impact on required manoeuvre control force to achieve a given control authority. A system is developed wherein a mass translates aft during flight inside a cavity aligned with the projectile centre-line, thereby altering the mass centre. This in turn decreases the projectile's static margin after launch and allows greater control authority later in flight, while at the same time decreasing initial throw-off errors. A seven-degree-of-freedom flight dynamic model is used to predict the performance of the system. Results show that by decreasing static margin after launch the proje...
Bernoulli measure on strings, and Thompson-Higman monoids

The Bernoulli measure on strings is used to define height functions for the dense \(\mathcal{ R}\)- and \(\mathcal{ L}\)-orders of the Thompson-Higman monoids M k,1. The measure can also be used to characterize the \(\mathcal{ D}\)-relation of certain submonoids of M k,1. The computational complexity of computing the Bernoulli measure of certain sets, and in particular, of computing the \(\mathcal{ R}\)- and \(\mathcal{ L}\)-height of an element of M k,1 is investigated.
Polyhedral study of the capacitated vehicle routing problem

The capacitated vehicle routing problem (CVRP) considered in this paper occurs when goods must be delivered from a central depot to clients with known demands, usingk vehicles of fixed capacity. Each client must be assigned to exactly one of the vehicles. The set of clients assigned to each vehicle must satisfy the capacity constraint. The goal is to minimize the total distance traveled. When the capacity of the vehicles is large enough, this problem reduces to the famous traveling salesman problem (TSP). A variant of the problem in which each client is visited by at least one vehicle, called the graphical vehicle routing problem (GVRP), is also considered in this paper and used as a relaxation of CVRP. Our approach for CVRP and GVRP is to extend the polyhedral results known for TSP. For example, the subtour elimination constraints can be generalized to facets of both CVRP and GVRP. Interesting classes of facets arise as a generalization of the comb inequalities, depending on whether the depot is in a handle, a tooth, both or neither. We report on the optimal solution of two problem instances by a cutting plane algorithm that only uses inequalities from the above classes.
Uses and abuses of wrist arthroscopy.

PURPOSE OF REVIEW The use of wrist arthroscopy in the diagnosis and treatment of carpal pathology continues to expand. The purpose of this paper is to summarize recent advances in the utility of this diagnostic, therapeutic, and research tool. RECENT FINDINGS The indications for wrist arthroscopy are growing with the description of volar portals for the radiocarpal and scaphotrapezial trapezoid joint. Arthroscopic assistance in the treatment of distal radius and scaphoid fractures is also becoming more feasible. Arthroscopic excision of dorsal carpal ganglions has met with considerable success. In addition, the application of electrothermal collagen shrinkage is an exciting new frontier in arthroscopic wrist procedures. SUMMARY Wrist arthroscopy has evolved to be an essential diagnostic and therapeutic tool in the armamentarium of every surgeon treating disorders of the wrist.
Lunar South Pole Illumination: Review, Reassessment, and Power System Implications

This paper reviews past analyses and research related to lunar south pole illumination and presents results of independent illumination analyses using an analytical tool and a radar digital elevation model. The analysis tool enables assessment at most locations near the lunar poles for any time and any year. Average illumination fraction, energy storage duration, solar/horizon terrain elevation profiles and illumination fraction profiles are presented for various highly illuminated sites which have been identified for manned or unmanned operations. The format of the data can be used by power system designers to develop mass optimized solar and energy storage systems. Data are presented for the worse case lunar day (a critical power planning bottleneck) as well as three lunar days during lunar south pole winter. The main site under consideration by present lunar mission planners (on the Crater Shackleton rim) is shown to have, for the worse case lunar day, a 0.71 average illumination fraction and 73 to 117 hours required for energy storage (depending on power system type). Linking other sites and including towers at either site are shown to not completely eliminate the need for energy storage.
A bird's-eye view on the evolution of semiconductor superlattices and quantum wells

Following the past seventeen-year developmental path in the research of semiconductor superlattices and quantum wells, significant milestones are presented with emphasis on experimental investigations in the device physics of reduced dimensionality performed in cooperation with the materials science of heteroepitaxial growth.
Dynamic Knowledge Map: reusing experts' tacit knowledge in the AEC industry

Abstract Much knowledge in the Architecture, Engineering and Construction (AEC) industry is experience-based and tacit. Nevertheless, the typical strategy for knowledge management is focused on computer-based approaches for capturing and disseminating explicit knowledge. AEC firms have been successful at collecting and storing explicit information in enterprise databases, but they are poor at knowledge retrieval and exchange. Consequently, AEC professionals find it difficult to reuse core experts' knowledge for highly knowledge-intensive AEC activities. This situation calls for a method for disseminating tacit knowledge from experts' brains to achieve higher quality AEC projects. The primary purpose of this paper is to set a theoretical foundation for clarifying the contribution of experts' tacit knowledge in the AEC industry. The secondary purpose is to describe the concept for prototype software, Dynamic Knowledge Map, that can assist in the reuse of experts' tacit knowledge. Dynamic Knowledge Map is a Web-based knowledge navigator that searches for experts and facilitates communication with those experts by using internet technology. Higher performance levels theoretically can be achieved while accelerating the knowledge transfer processes. Future research will test the suitability of Dynamic Knowledge Map for tacit knowledge utilization in AEC organizations.
Compressive binary search

In this paper we consider the problem of locating a nonzero entry in a high-dimensional vector from possibly adaptive linear measurements. We consider a recursive bisection method which we dub the compressive binary search and show that it improves on what any nonadaptive method can achieve. We also establish a non-asymptotic lower bound that applies to all methods, regardless of their computational complexity. Combined, these results show that the compressive binary search is within a double logarithmic factor of the optimal performance.
The limits of tax and expenditure limits: TEL implementation as a principal-agent problem

Previous scholarship has shown that Tax and Expenditure Limits (TELs) often fail to constrain government growth. This paper views the implementation of TELs as a principal-agent problem. Agency theory predicts that delegation is affected by the preferences of agents and the costs of monitoring those agents. Using panel data for the US states from 1970 through 2008, I conduct an empirical test of the validity of the principal-agent model for TELs. I find that state spending limitations are only effective at cutting the growth of state and local spending under the direction of agents who have a preference for limited government. Additionally, state property tax limitations are only effective when monitoring does not require costly coordinated action. These findings contradict an alternative theory of TEL implementation that looks towards the policy’s origin. My research suggests that the arrangements of delegation determine when and under what conditions TELs effectively reduce government growth.
Techniques for requirements-oriented design

The purpose of this paper is to discuss how requirement studies can be performed for computer systems. There are many different types of requirement studies that can be used to define a system and a number of these are described.
Wear Mechanisms of Untreated and Gamma Irradiated Ultra-High Molecular Weight Polyethylene for Total Joint Replacements

Modification of the surface microstructure of ultra-high molecular weight polyethylene (UHMWPE) is essential for improving the wear resistance of orthopedic implants. A common approach is to cross-link the polymer by gamma irradiation. The objective of this study was to examine the tribological behaviors of untreated and gamma irradiated UHMWPE under physiologically relevant contact conditions. Emphasis was placed on the identification of the dominant wear mechanisms in the early stage of polymer wear. The irradiation dose exhibited a strong effect on the tribological properties of UHMWPE sliding against Co-Cr alloy in a bath of bovine serum. Transmission electron microscopy (TEM) and environmental scanning electron microscopy (ESEM) were used to examine the microstructure and morphology of the worn surfaces. Regularly spaced folds with average spacing depending on the irradiation dose (i.e., cross-link density) formed on the wear tracks. Surface folding was related to plastic flow and the degree of mobility of the crystalline lamellae. SEM and TEM results elucidated the roles of the cross-link density and crystalline lamellae in the wear process. Based on the experimental evidence, a deformation model was obtained that provides explanation for the dependence of surface folding on the cross-link density and lamellae reorientation during sliding.
Consumer's Surplus versus Compensating Variation Revisited

Consumer's surplus and a second-order approximation to compensating variation are compared to the exact compensating variation for a subsystem of several commodities. An empirical application to the relative retail price distortions created by the U.S. dairy program is presented. In the application, a new specification for weakly integrable incomplete demand models is developed and estimated. The integrable demand model has sufficient flexibility that it is not rejected by the data. Both welfare approximations are found to introduce large errors in the measurement of deadweight losses.
Modeling and Analyzing the Material Flow of Crowdsourcing Processes in Cloud-Based Manufacturing Systems Using Stochastic Petri Nets

Cloud-based manufacturing (CBM), also referred to as cloud manufacturing, has the potential to allow manufacturing enterprises to be rapidly scaled up and down by crowdsourcing manufacturing tasks or sub-tasks. To improve the efficiency of the crowdsourcing process, the material flow of CBM systems needs to be managed so that several manufacturing processes can be executed simultaneously. Further, the scalability of manufacturing capacity in CBM needs to be designed, analyzed, and planned in response to rapidly changing market demands. The objective of this paper is to introduce a stochastic petri nets (SPNs)-based approach for modeling and analyzing the concurrency and synchronization of the material flow in CBM systems. The proposed approach is validated through a case study of a car suspension module. Our results have shown that the SPN-based approach helps analyze the structural and behavioral properties of a CBM system and verify manufacturing performance.Copyright © 2014 by ASME
The social implications of higher level thinking skills

This paper describes theoretical and empirical research suggesting that individuals who are capable of perceiving others in complex and divergent ways may be able to communicate more effectively, adapting verbal messages to fit the perspectives of listeners. This proposition represents a link between several fields of inquiry that researchers rarely interrelate: higher level thinking skills, social cognition, social competency, and communications. Key concepts within each field are historically defined, and directions for future research are outlined.