cssi/SciSciGPT-SciSciNet huggingface dataset:
Smallholder Market Participation: Concepts and Evidence from Eastern and Southern Africa

Abstract This paper reviews the evidence on smallholder market participation, with a focus on staple foodgrains (i.e., cereals) in eastern and southern Africa, in an effort to help better identify what interventions are most likely to break smallholders out of the semi-subsistence poverty trap that appears to ensnare much of rural Africa. The conceptual and empirical evidence suggests that interventions aimed at facilitating smallholder organization, at reducing the costs of intermarket commerce, and, perhaps especially, at improving poorer households’ access to improved technologies and productive assets are central to stimulating smallholder market participation and escape from semi-subsistence poverty traps. Macroeconomic and trade policy tools appear less useful in inducing market participation by poor smallholders in the region.
P-glycoprotein function at the blood–brain barrier in humans can be quantified with the substrate radiotracer [11C]-N-desmethyl-loperamide

Permeability-glycoprotein (P-gp), an efflux transporter in several organs, acts at the blood–brain barrier to protect the brain from exogenous toxins. P-gp almost completely blocks brain entry of the PET radiotracer 11C-N-desmethyl-loperamide (11C-dLop). We examined the ability of 11C-dLop to quantify P-gp function in humans after increasing doses of tariquidar, an inhibitor of P-gp. Methods: Seventeen healthy volunteers had a total of 23 PET scans with 11C-dLop at baseline and after increasing doses of tariquidar (2, 4, and 6 mg/kg intravenously). A subset of subjects received PET with 15O-H2O to measure cerebral blood flow. Brain uptake of 11C-dLop was quantified in 2 ways. Without blood data, uptake was measured as area under the time–activity curve in the brain from 10 to 30 min (AUC10–30). With arterial blood data, brain uptake was quantified with compartmental modeling to estimate the rates of entry into (K1) and efflux from (k2) the brain. Results: Brain uptake of radioactivity was negligible at baseline and increased only slightly (∼30%) after 2 mg of tariquidar per kilogram. In contrast, 4 and 6 mg of tariquidar per kilogram increased brain uptake 2- and 4-fold, respectively. Greater brain uptake reflected greater brain entry (K1), because efflux (k2) and cerebral blood flow did not differ between tariquidar-treated and untreated subjects. In the subjects who received the highest dose of tariquidar (and had the highest brain uptake), regional values of K1 correlated linearly with absolute cerebral blood flow, consistent with high single-pass extraction of 11C-dLop. AUC10–30 correlated linearly with K1. Conclusion: P-gp function at the blood–brain barrier in humans can be quantified using PET and 11C-dLop. A simple measure of brain uptake (AUC10–30) may be used as a surrogate of the fully quantified rate constant for brain entry (K1) and thereby avoid arterial sampling. However, to dissect the function of P-gp itself, both brain uptake and the influx rate constant must be corrected for radiotracer delivery (blood flow).
A new route to early-late heterobimetallic μ-alkylidene complexes

Abstract The reaction of two equivalents of Cp 2 ZrHCl ( 1 ) with Cp(CO) 2 ReCHR ( 2 , R = CH 2 CH 2 CMe 3 ; 4 , R = CH 3 ) led to the formation of the heterobimetallic μ-alkylidene complexes Cp 2 Zr(μ-CHR)(μ,η 1 ,η 2 -CO)Re(CO)Cp ( 3 , R = CH 2 CH 2 CMe 3 ; 5 , R = CH 3 ).
Cyber-physical and networked sensor systems: challenges and opportunities

Rapid advancements in embedded systems, sensors and wireless communication technologies have led to the development of cyber-physical systems, pervasive computing and smart environments with important applications such as smart grids, sustainability, health care and security. Wireless sensor networks play significant role in building such systems as they can effectively act as the human-physical interface with the digital world through sensing, communication, computing and control or actuation. However, the inherent characteristics of wireless sensor networks, typified by resource constraints, high degree of uncertainty, heterogeneity and distributed control pose significant challenges.This tutorial will provide a guided tour of (i) the characteristics and applications of cyber-physical systems and sensor networks, (ii) associated technical challenges and opportunities, and (iii) novel algorithmic frameworks and solutions for data collection from sensor streams, sensor data fusion, multi-modal context recognition, and situation-aware decision making. The common goal is to minimize energy consumption (i.e., maximize life time) and increase information accuracy (i.e., context quality) in wireless sensor networks. The tutorial will be concluded with open issues and future directions of research.
Erupting prominences and the geometry of coronal mass ejections

Studies of the origins of coronal mass ejections (CMEs) show a strong association between CMEs and erupting prominences. 'Loop' CMEs form the most common morphological class for both Skylab and Solar Maximum Mission (SMM) and the class most likely to be associated with erupting prominences. In the optically thin corona, the geometry of such structures is interpreted as either planar (two-dimensional), shell-like, or bubblelike (three-dimensional) structures. Trottet and MacQueen (1980) (hereinafter referred to as TM) first examined the orientations of prominences associated with Skylab CMEs and argued that looplike CMEs were planar structures in the plane of the sky. In this work, the initial orientations of prominences identified with SMM CMEs in 1980 were measured in order to examine the overall geometry of CMEs. Contrary to TM's result, no preferred orientation for prominences associated with SMM CMEs nor any difference between that population and the population of all disk filaments were found. In addition, plots comparing CME/filament orientation angles and the angular widths of the CME envelopes show large scatter. Taken together, these results support a shell-like rather than a planar geometry for at least looplike CMEs.
Extracting and using photon polarization information in radiative B decays

The authors discuss the uses of conversion electron pairs for extracting photon polarization information in weak radiative B decays. Both cases of leptons produced through a virtual and real photon are considered. Measurements of the angular correlation between the (K-pi) and (e{sup +}e{sup {minus}}) decay planes in B --> K*(--> K-pi)gamma (*)(--> e{sup +}e{sup {minus}}) decays can be used to determine the helicity amplitudes in the radiative B --> K*gamma decays. A large right-handed helicity amplitude in B-bar decays is a signal of new physics. The time-dependent CP asymmetry in the B{sup 0} decay angular correlation is shown to measure sin 2-beta and cos 2-beta with little hadronic uncertainty.
Factorial and Noetherian subrings of power series rings

Let F be a field. We show that certain subrings contained between the polynomial ring F[X] = F[X1, ⋯ ,Xn] and the power series ring F[X][[Y ]] = F[X1, ⋯ ,Xn][[Y ]] have Weierstrass Factorization, which allows us to deduce both unique factorization and the Noetherian property. These intermediate subrings are obtained from elements of F[X][[Y ]] by bounding their total X-degree above by a positive real-valued monotonic up function λ on their Y -degree. These rings arise naturally in studying the p-adic analytic variation of zeta functions over finite fields. Future research into this area may study more complicated subrings in which Y = (Y1, ⋯ , Ym) has more than one variable, and for which there are multiple degree functions, λ1, ⋯ , λm. Another direction of study would be to generalize these results to k-affinoid algebras. © 2010 American Mathematical Society.
A decision-theoretic approach to resource allocation in wireless multimedia networks

The allocation of scarce spectral resources to support as many user applications as possible while maintaining reasonable quality of service is a fundamental problem in wireless communication. We argue that the problem is best formulated in terms of decision theory. We propose a scheme that takes decision-theoretic concerns (like preferences) into account and discuss the difficulties and subtleties involved in apply standard techniques from the theory of Markov Decision Processes (MDPs) in constructing an algorithm that is decision-theoretically optimal. As an example of the proposed framework, we construct such an algorithm under some simplifying assumptions. Additionally, we present analysis and simulation results that show that our algorithm meets its design goals. Finally, we investigate how far from optimal one well-known heuristic is. The main contribution of our results is in providing insight and guidance for the design of near-optimal admission-control policies.
Synthesis of (+), (-)- and (±)-7'-hydroxyabscisic acid

Abstract A total synthesis of 7′-hydroxyabscisic acid (1), a putative metabolite of the plant hormone abscisic acid (ABA), is described. The key intermediate in the twelve step synthesis is 2-t-butyldimethylsiloxymethyl-4,4-ethylenedioxy-6,6-dimethylcyclohex-2-en-1-one (5) which contains the desired masked hydroxyl group at the C-7′ position of ABA. The final transformation in the synthesis, the hydrolysis of the methyl ester of 1 is readily accomplished with porcine liver esterase. Optically pure (+)- and (−)-forms of 1 are obtained by resolution of the silyl ether methyl ester by HPLC on a chiral column.
The resonance effect of a wire in response to transient waves

A resonance effect of transient fields on a thin conducting wire is described. Based on the analysis of the wire's characteristic spectrum, its backscatter, bistatic, and specular scattering are investigated in response to a one-cycle sine waveform. The responding waveforms are discussed in terms of traveling waves. It is found that the resonance effect is directly associated with the excitation of a very strong traveling wave.
Fluidic Flame Stabilization in a Planar Combustor Using a Transverse Slot Jet

T HE stabilization of a premixed flame in a high-speed internal environment has received a considerable amount of interest from many researchers, for example, [1–3]. Flame stabilization behind a bluff body represents the most common strategy for flame anchoring [4–8]. Bluff bodies and rearward-facing step flows stabilize the flame by introducing a low-velocity recirculation zone containing combustion products that act as a continuous ignition source. Although these flame-holding devices provide an environment suitable for flame holding, a drag penalty is incurred. An alternative fluidic-based approach using a transverse slot jet to generate a “virtual bluff body” would reduce the thrust penalties through the removal of form drag while producing a flowfield with flame-holding potential. Figure 1 shows two schematics for combustors employing bluff body and fluidic methods for flame holding. The dashed box in the figure represents the control volume that will be used to demonstrate that form drag imposes a penalty. A momentum balance in the streamwise direction for the two situations, employing the assumption of negligible viscous shear, indicates that the drag force on the bluff body FD will result in a loss in either streamwise momentum or an increased pressure drop across the burner. For the fluidic case, a balancewill be maintained between pressure drop and an increase in streamwise momentum. A simple one-dimensional analysis of the systems, shown in Fig. 1, using a drag coefficient based on the inlet flow properties was conducted to determine the additional total pressure losses due to flame-holder drag. The calculation employs constant specific heats, models the fluid as air, and employs conservation of mass, momentum, the ideal gas equation, Mach number definition, and stagnation relations. Figure 2 shows the additional total pressure loss due to form drag on the flame holder as a function of inlet Mach number and drag coefficient. In addition to thrust penalty reduction, the fluidic flame holder allows active control of the recirculation zone size, providing dynamic control of the stabilization characteristics that will allow a broader operating envelope and improved off-design performance. Dynamic control would allow for optimization of the tradeoff between combustion efficiency and flame stability. The cost of the fluidic actuation is considered in terms of the required mass flow rate to achieve the necessary recirculation zone. For the present experiments, the fluidic flow ratewas nominally 7% of themain flow rate. The objective of the current note is to document the operating characteristics of a fluidic flame holder consisting of a planar transverse jet issuing into a channel flow. The influence of the test chamber initial conditions on the scaling of the induced recirculation zonewill be shown. It will also be shown that the jet equivalence ratio can be used to manipulate the rich and lean blowout limits.
Ethical dilemmas in a professional service context

This paper reports on the results of action research exploring the kinds of ethical problems that confront employees in the professional services industry. Data were collected from a single firm via participant observation methods at eight locations across the country. Issues raised included service delivery, responses to life threatening situations, marketing, client relationships, client entertaining, bribery, billings, as well as intra-firm issues such as support for professional judgments in the field, employee health and safety, and compensation. The paper concludes with an assessment of the utility of the approach taken by the firm, the generalizability of the issues beyond the single case setting, as well as an assessment of the managerial issues related to fostering and sustaining an ethical environment within a business organization.
Configurational Stability and Transfer of Stereochemical Information in the Reactions of Enantioenriched Organolithium Reagents

The conversion of a prochiral methylene group into a stereogenic center by means of a lithiation/substitution sequence has emerged as a powerful synthetic transformation over the past 15 years. This reaction proceeds via a chiral organolithium intermediate, and the stereochemical fidelity of the overall reaction sequence is intimately dependent on the stereochemical behavior of the chiral organolithium as well as on the rate and stereochemical sense of the electrophilic substitution step. Chiral organolithium reagents were first reported by Letsinger, Curtin, and Applequist half a century ago. The lithiated intermediates in these early studies were not highly configurationally stable, and applications in stereoselective synthesis were not immediately forthcoming. The two decades that followed the 1980 report by Still and Sreekumar of a configurationally stable α-oxyorganolithium were marked by an increased interest in these reagents. As the synthetic applications of chiral organolithium reagents have grown, so have accompanying mechanistic studies of these intermediates which serve as the basis for this review.
REGULATION BY PRICES AND BY COMMAND.

Standard economic theory states that regulation by price is more efficient than regulation by command and control. Exceptions may arise if regulators have good knowledge of the supply curve. In practice, though, governments usually regulate by command and control and do so when there is uncertainty about the technology of supply. We show that government may prefer to regulate by command and control when it cares about the investment decisions of a firm.
Contribution of environment and genetics to pancreatic cancer susceptibility.

Several risk factors have been identified as potential contributors to pancreatic cancer development, including environmental and lifestyle factors, such as smoking, drinking and diet, and medical conditions such as diabetes and pancreatitis, all of which generate oxidative stress and DNA damage. Oxidative stress status can be modified by environmental factors and also by an individual's unique genetic makeup. Here we examined the contribution of environment and genetics to an individual's level of oxidative stress, DNA damage and susceptibility to pancreatic cancer in a pilot study using three groups of subjects: a newly diagnosed pancreatic cancer group, a healthy genetically-unrelated control group living with the case subject, and a healthy genetically-related control group which does not reside with the subject. Oxidative stress and DNA damage was evaluated by measuring total antioxidant capacity, direct and oxidative DNA damage by Comet assay, and malondialdehyde levels. Direct DNA damage was significantly elevated in pancreatic cancer patients (age and sex adjusted mean ± standard error: 1.00±0.05) versus both healthy unrelated and related controls (0.70±0.06, p A and ERCC4 R415Q polymorphisms. These results suggest that measurement of DNA damage, as well as select SNPs, may provide an important screening tool to identify individuals at risk for development of pancreatic cancer.
A General Strain Theory of Racial Differences in Criminal Offending

Since 1992, General Strain Theory (GST) has earned strong empirical support and has been applied to several key correlates of crime (e.g., age, sex, community), but researchers have yet to fully consider how GST may aid in explaining racial differences in offending. While most explanations focus on macro level and macro-micro control processes, we argue that GST complements these explanations by highlighting the emotional and motivational social psychological processes that underlie criminal behaviour, thereby filling an important theoretical gap. In particular, we argue that African-Americans are likely to experience more and qualitatively unique types of strain compared to Whites, and that these strains in turn lead to higher levels of negative emotions among African-Americans. Further, we argue that the unique social conditions in which many African-Americans live may disproportionately lead them to cope with strain and negative emotions through crime. We believe these theoretical insights can guide future empirical research to create a fuller understanding of racial differences in offending.
Performance of metal meshes as a function of incidence angle.

An inductive mesh was measured for transmission as a function of frequency, incidence angle, and polarization. The experimental data agree well with Chen’s waveguide theory for meshes as long as an adequate number of modes are included in the calculations. To simplify calculations of mesh transmission a lumped circuit model has been developed to fit Chen’s theory. This model predicts transmission for the two major polarizations and a variety of angles to within 1%.
Alloantigen gene therapy for head and neck cancer: Evaluation of animal models

Background. Human trials of alloantigen gene therapy, using the class I major histocompatibility complex (MHC) HLA-B7, have demonstrated the potential efficacy of this treatment for head and neck cancer. Its mechanism remains unclear. An immune-competent mouse model of MHC gene therapy to test factors potentially important to the tumor response is needed. Methods. Two cell lines were used, B4B8 cells that grow in Balb/c mice and SCC-VII cells that grow in C3H mice. The mouse MHC H2-Kb was used as the therapeutic gene, because it is an alloantigen to both mice strains. Plasmids that encode the H2-Kb cDNA were prepared, and the cell lines were transfected. Mice were injected subcutaneously with naive cells to determine the tumor kinetics and serve as controls. Mice were injected with H2-Kb transfected cells and tumor growth was compared with controls. Mice that did not grow tumor were rechallenged with naive cells to assess for tumor immunity. Mice were injected with transfected and naive cells admixed to determine whether the concentration of the alloantigen is important. Results. B4B8 tumors grew slowly, whereas SCC-VII tumors grew rapidly. Transfection with H2-Kb plasmid prevented or inhibited tumor growth of both the B4B8 and SCC-VII tumors. This growth inhibition was independent of the number of cells injected. In the mice that did not grow tumor, tumor immunity was demonstrated after challenge with naive cells in both models. There was no relationship between induction of immunity and the timing of the challenge or initial cell quantity. The mice injected with a mixture of naive and transfected cells grew tumor, although growth was delayed in the B4B8 model. Conclusions. The results demonstrate that the two mouse models can serve as a rapid and slow growing tumor model of alloantigen gene therapy. In addition, it was noted that initial tumor cell number is not a significant factor for predicting tumor response and demonstrated that in both of these models alloantigen gene therapy results in significant antitumor immunity. © 2003 Wiley Periodicals, Inc. Head Neck 25: 274–279, 2003
Integrating user interface agents with conventional applications

In most experiments with user interface agents to date, it has been necessary either to implement both the agent and the application from scratch, or to modify the code of an existing application to enable the necessary communication. Instead, we would like to be able to `attach' an agent to an existing application, while requiring only a minimum of advance planning on the part of the application developer. Commercial applications are increasingly supporting the use of `application programmers' interfaces' and scripting languages as means of achieving external control of applications. Are these mechanisms sufficient for software agents to achieve communication with applications? This paper reports some preliminary experiments in developing agent software that works with existing, unmodified commercial applications and agents that work across multiple applications. We describe a programming by example agent, ScriptAgent, that uses a scripting language, Applescript, to record example procedures that are generalized by the agent. Another approach is examinability, where the application grants to the agent the right to examine internal data structures. We present another kind of learning agent, Tatlin, that compares successive application states to infer interface operations. Finally, we discuss broader systems issues such as parallelism, interface sharing between agent and application, and access to objects.
S&P ETFs: Arbitrage Opportunities and Market Forecasting

The article examines the pricing differences between two SP however, the level of the daily premium (and, on occasion, discount) varies between the two securities, which creates the opportunity for arbitrage. Since the passage of Regulation NMS in mid-2005, the pricing differences, as expected, have declined, implying that any current/future arbitrage opportunity will be confined to periods of high market volatility, such as 2008. Beyond issues related to arbitrage, the author finds that the relative pricing of the ETFs also provides a valuable signal of future (particularly next day) market activity. Thus, he suggests that active traders and longer-term investors may both benefit from recognition of relative ETF prices.
The Language Instinct

In this "extremely valuable book, very informative, and very well written" (Noam Chomsky), one of the greatest thinkers in the field of linguistics explains how language works--how people, ny making noises with their mouths, can cause ideas to arise in other people's minds.
The Uncertainty of Economic Success When Economic Regimes Are Uncertain: A Study of Transition Periods

We construct a model of a reform economy in transition from central planning to free markets. The eventual success of the reform is uncertain. A numerical implementation of the model examines the implications of two alternative paths, instantaneous or gradual price reform. If the controlled-price sector has sharply decreasing returns to scale in production, then gradualism may lead to welfare higher than that of instantaneous reform. Given the inefficiencies in production in many transition economies, this may help to explain why countries that have used gradualism have sometimes fared better than those that have followed a path of rapid price liberalization. J. Comp. Econom., October 1994, 19(2), pp. 217-236. University of Kansas, Lawrence, Kansas 66045.
Indexing for Data Models with Constraints and Classes

We examine I/O-efficient data structures that provide indexing support for new data models. The database languages of these models include concepts from constraint programming (e.g., relational tuples are generalized to conjunctions of constraints) and from object-oriented programming (e.g., objects are organized in class hierarchies). Let $n$ be the size of the database, $c$ the number of classes, $B$ the secondary storage page size, and $t$ the size of the output of a query. Indexing by one attribute in the constraint data model (for a fairly general type of constraints) is equivalent to external dynamic interval management, which is a special case of external dynamic 2-dimensional range searching. We present a semi-dynamic data structure for this problem which has optimal worst-case space $O(n/B)$ pages and optimal query I/O time $O(\log_B n + t/B)$ and has $O(\log_B n + (\log^2_B n) / B)$ amortized insert I/O time. If the order of the insertions is random then the expected number of I/O operations needed to perform insertions is reduced to $O(\log_B n)$. Indexing by one attribute and by class name in an object-oriented model, where objects are organized as a forest hierarchy of classes, is also a special case of external dynamic 2-dimensional range searching. Based on this observation we first identify a simple algorithm with good worst-case performance for the class indexing problem. Using the forest structure of the class hierarchy and techniques from the constraint indexing problem, we improve its query I/O time from $O(\log_2 c \log_B n +t/B)$ to $O(\log_B n + t/B + \log_2 B)$.
Nonprofit Ownership, Private Property, And Public Accountability

Mark Schlesinger and Brad Gray have summarized research comparing nonprofit and for-profit health care in a remarkably useful form. Their paper effectively demonstrates how nonprofit and for-profit health care differ. However, their proposal for community control over nonprofit health care organizations in exchange for tax exemption, like many current proposals requiring nonprofit hospitals to provide free care for indigent patients, risks undermining the purpose of the nonprofit organizations and the care they provide. These trade-offs are significant yet have not been acknowledged in policy debate.
A posteriori image-correcting ''deconvolution'' by holographic Fourier-transform division.

Abstract Division of spatial field distributions in the Fourier-transform domain for “resolution-retrieving”, “corrective” image deconvolution of the “smearing” resulting from extended “instrument functions” in optical imaging, spectroscopy and radio-astronomy may be accomplished by a “two-filter” holographic scheme.
Strengthening the International Financial System: Key Issues

Abstract There has been notable progress in reforming the international financial system in order to improve the resilience of the world economy to volatility in international capital flows. This paper focuses on three critical issues central to the effort to reduce the frequency and virulence of crises: (a) exchange rate regimes, both amongst major industrial countries and for emerging market economics; (b) capital account liberalization, whether and how it should be done; and (c) the role of IMF lending in crisis prevention and management, and in particular the critical question of how to involve the private sector in the resolution of financial crises.
870 Micron Observations of Nearby 3CRR Radio Galaxies

We present submillimeter continuum observations at 870 μm of the cores of low-redshift 3CRR radio galaxies, observed at the Heinrich Hertz Submillimeter Telescope. The cores are nearly flat-spectrum between the radio and submillimeter, which implies that the submillimeter continuum is likely to be synchrotron emission and not thermal emission from dust. The emitted power from nuclei detected at optical wavelengths and in the X-rays is similar in the submillimeter, optical, and X-rays. The submillimeter-to-optical and X-ray power ratios suggest that most of these sources resemble misdirected BL Lac–type objects with synchrotron emission peaking at low energies. However, we find three exceptions, the FR I galaxy 3C 264 and the FR II galaxies 3C 390.3 and 3C 338 with high X-ray–to–submillimeter luminosity ratios. These three objects are candidate misdirected high- or intermediate-energy peaked BL Lac–type objects. With additional infrared observations and from archival data, we compile spectral energy distributions for a subset of these objects. The steep dips observed near the optical wavelengths in many of these objects suggest that extinction inhibits the detection and reduces the flux of optical continuum core counterparts. High-resolution near- or mid-infrared imaging may provide better measurements of the underlying synchrotron emission peak.
Dose-dependent effects of peptide YY(3-36) on conditioned taste aversion in rats

We used a conditioned taste aversion test to assess whether PYY(3-36) reduces food intake by producing malaise. Two-hour IV infusion of PYY(3-36) (8, 15, and 30 pmol/kg/min) at dark onset in non-food-deprived rats produced a dose-dependent inhibition of feeding and a conditioned aversion to the flavored chow paired with PYY(3-36) infusion. In food-deprived rats, PYY(3-36) at 2 and 4 pmol/kg/min inhibited intake of a flavored saccharin solution without producing conditioned taste aversion, whereas higher doses (8 and 15 pmol/kg/min) inhibited saccharin intake and produced taste aversion. These results suggest that anorexic doses of PYY(3-36) may produce a dose-dependent malaise in rats, which is similar to that reported for PYY(3-36) infusion in humans. Previous studies have shown that PYY(3-36) potently inhibits gastric emptying, and that gut distention can produce a conditioned taste aversion. Thus, PYY(3-36) may produce conditioned taste aversion in part by slowing gastric emptying.
Interior characteristics at mid-levels of thunderstorms in the southeastern United States

Data characterizing the updraft structures and hydrometers observed in moderate thunderstorms by the armored T-28 aircraft during the 1986 Cooperative Huntsville Meteorological Experiment (COHMEX) are presented. Updraft regions in the storms were relatively narrow, but usually very turbulent. The vertical winds were generally weak, the peak updraft speeds usually being <5 m s−1; the absolute maximum was 19 m s−1. Cloud liquid-water concentrations measured between the −7.5°C and +5.5°C levels were typically <25% of adiabetic values. Size spectra for the precipitation particles appear truncated, with very high concentrations of particles with sizes between 1 and 5 mm and few larger than 8 mm. hail occured in less than 25% of the penetrations, and particles larger than about 1 cm were very infrequent, despite reflectivities often between 50 and 60 dBz. The large numbers of precipitation-size particles usually found in the updraft regions that appeared to be well-mixed indicate that a coalescence mechanism was active in the COHMEX storms. The depth warm cloud, the generally weak updrafts, and the presence of large cloud droplets all support a coalescence mechanism. Ice processes also must play a role in precipitation development because most COHMEX storms were characterized by extremely deep convection. However, the high conceentrations of growth centers observed at T-28 penetration levels suggest that a natural “beneficial competition” process limits the growth of large particles.
Two-dimensional depth-resolved Mueller matrix characterization of biological tissue by optical coherence tomography.

We built a polarization-sensitive optical coherence tomographic system and measured the two-dimensional depth-resolved full 4×4 Mueller matrix of biological tissue for what is believed to be the first time. The Mueller matrix measurements, which we made by varying the polarization states of the light source and the detector, yielded a complete characterization of the polarization property of the tissue sample. The initial experimental results indicated that this new approach reveals some tissue structures that are not perceptible in standard optical coherence tomography.
Why Do Vortices Generate Sound

Emphasizing physical pictures with a minimum of analysis, an introductory account is presented as to how vortices generate sound. Based on the observation that a vortex ring induces the same hydrodynamic (incompressible) flow as does a dipole sheet of the same shape, simple physical arguments for sound generation by vorticity are presented, first in terms of moving vortex rings of fixed strength and then of fixed rings of variable strength. These lead to the formal results of the theory of vortex sound, with the source expressed in terms of the vortex force ρ(u ∧ ζ) and of the form introduced by Mohring in terms of the vortex moment (y ∧ ζ′), (ρ is the constant fluid density, u the flow velocity, ζ = ∇ ∧ u the vorticity and y is the flow coordinate). The simple “Contiguous Method” of finding the contiguous acoustic field surrounding an acoustically compact hydrodynamic (incompressible) field is also discussed. Some very simple vortex flows illustrate the various ideas. These are all for acoustically compact, low Mach number flows of an inviscid fluid, except that a simple argument for the effect of viscous dissipation is given and its relevance to the “dilatation” of a vortex is mentioned.
Exactly solvable approximating models for Rabi Hamiltonian dynamics

The interaction between an atom and a one mode external driving field is an ubiquitous problem in many branches of physics and is often modeled using the Rabi Hamiltonian. In this paper we present a series of analytically solvable Hamiltonians that approximate the Rabi Hamiltonian and compare our results to the Jaynes-Cummings model which neglects the so-called counter-rotating term in the Rabi Hamiltonian. Through a unitary transformation that diagonalizes the Jaynes-Cummings model, we transform the counter-rotating term into separate terms representing several different physical processes. By keeping only certain terms, we can achieve an excellent approximation to the exact dynamics within specified parameter ranges.
Managerial ownership with rent-seeking employees

In some cases, the incentives of the manager will affect the behavior of the firm’s employees. A manager with low-powered incentives will discourage employees from engaging in destructive rent-seeking activities. Union members will need to cooperate with this poorly compensated manager if the firm will have any chance to succeed. The elimination of rent-seeking costs can increase the value of owners’ stakes in the firm. Thus, value can be maximized by giving control to a CEO with an ownership stake strictly less than 100 percent.
Wacker-Type Oxidation of Internal Alkenes using Pd(Quinox) and TBHP

The Pd-catalyzed TBHP-mediated Wacker-type oxidation of internal alkenes is reported. The reaction uses 2-(4,5-dihydro-2-oxazolyl)quinoline (Quinox) as ligand and TBHP(aq) as oxidant to deliver single ketone constitutional isomer products in a predictable fashion from electronically biased olefins. This methodology is showcased through its application on an advanced intermediate in the total synthesis of the antimalarial drug artemisinin.
Theoretical Implications of the PSR B1620?26 Triple System and Its Planet

We present a new theoretical analysis of the PSR B1620-26 triple system in the globular cluster M4, based on the latest radio pulsar timing data, which now include measurements of five time derivatives of the pulse frequency. These data allow us to determine the mass and orbital parameters of the second companion completely (up to the usual unknown orbital inclination angle i2). The current best-fit parameters correspond to a second companion of planetary mass, m2 sin i2 7 × 10-3 M☉ , in an orbit of eccentricity e2 0.45 and semimajor axis a2 60 AU. Using numerical scattering experiments, we study a possible formation scenario for the triple system, which involves a dynamical exchange interaction between the binary pulsar and a primordial star-planet system. The current orbital parameters of the triple are consistent with such a dynamical origin and suggest that the separation of the parent star-planet system was very large, 50 AU. We also examine the possible origin of the anomalously high eccentricity of the inner binary pulsar. While this eccentricity could have been induced during the same dynamical interaction that created the triple, we find that it could equally well arise from long-term secular perturbation effects in the triple, combining the general relativistic precession of the inner orbit with the Newtonian gravitational perturbation of the planet. The detection of a planet in this system may be taken as evidence that large numbers of extrasolar planetary systems, not unlike those discovered recently in the solar neighborhood, also exist in old star clusters.
Leading-Edge-Vortex Augmentation in Compressible Flow

Leading-edge-vortex enhancement by blowing has been explored experimentally. Conceptual half-span windtunnel tests were conducted on a wing-body-tail configuration with a cambered and twisted wing with leadingedge flaps. Blowing vortex augmentation is shown to be effective in improving both lift and drag due to lift at high angle of attack for the Mach numbers tested, M=0.3 and 0.75. Drag improvement results, in part, from an apparent vortex-suction effect on the cambered wing.
Facile Synthesis of the Tridecameric Al13 Nanocluster Al13(μ3-OH)6(μ2-OH)18(H2O)24(NO3)15

Treatment of aluminum nitrate with an organic nitroso-containing compound yields the “flat”, tridecameric nanocluster Al13(μ3-OH)6(μ2-OH)18(H2O)24(NO3)15 (Al13) in good yield on a preparative scale under ambient conditions. Synthetic procedures yielding two different single-crystal forms of the Al13 cation with two varying counterion compositions are described.
The Sum-Rate Bound for a New Class of Quadratic Gaussian Multiterminal Source Coding Problems

In this paper, we show tightness of the Berger-Tung (BT) sum-rate bound for a new class of quadratic Gaussian multiterminal (MT) source coding problems dubbed bi-eigen equal-variance with equal distortion (BEEV-ED), where the L × L source covariance matrix has equal diagonal elements with two distinct eigenvalues, and the L target distortions are equal. Let K (K <; L) be the number of repetitions of the larger eigenvalue, the BEEV covariance structure allows us to connect K i.i.d. virtual Gaussian sources with the L given MT sources via an L × K semiorthogonal transform whose rows have equal Euclidean norm plus additive i.i.d. Gaussian noises, resulting in the two sets of sources being mutually conditional i.i.d. By relating the given MT source coding problem to a generalized Gaussian CEO problem with the K virtual sources as remote sources and the L MT sources as observations, we obtain a lower bound on the MT sum-rate, and show its achievability by BT schemes under the equal distortion constraints. Our BEEV-ED class of quadratic Gaussian MT source coding problems subsumes both the positive-symmetric case considered by Wagner et al. and the negative-symmetric case. Other examples, including a subclass of sources with BE circulant symmetric covariance matrices and equal distortion constraints, are also provided to highlight tightness of the sum-rate bound.
The chemistry of the carbon–transition metal double and triple bond: annual survey covering the year 1998

Abstract This survey is intended to be a comprehensive summary of articles, which report on the synthesis, reactivity, or properties of compounds that feature a multiple bond between carbon and a transition metal. Reactions that employ metal carbene complexes as transient intermediates generated through well-established routes [this subject was reviewed in 1998: M.P. Doyle, M.N. Protopopova, Tetrahedron 54 (1998) 7919] are not covered unless there is some effort to characterize the carbene complex intermediate. Although a determined effort has been made to include patents, in general only patents that focus on carbene complexes and not polymer products will be included. Only compounds which feature a multiple bond between one carbon atom and one transition metal are discussed in this survey, thus bridging carbene and carbyne complexes are not covered unless there is a multiple bond to at least one transition metal. The complexes of stable carbenes with transition metals have not been included; since the π-donation component of these complexes is minimal, there is no formal carbon–metal multiple bond [see J.C. Green, R.G. Scurr, P.R. Arnold, F.G.N. Cloke, J. Chem. Soc. Chem. Commun. (1997) 1963, and A.A. Danopoulos, D.M. Hankin, G. Wilkinson, S.M. Cafferkey, T.K.N. Sweet, M.B. Hursthouse, Polyhedron 16 (1997) 3879]. This survey has been divided into two sections, metal carbene (or alkylidene) complexes and metal carbyne (or alkylidyne) complexes; the carbene complex section represents the vast majority of this article. The metal carbene section has been organized according to metal, starting from the left side of the periodic table. A special section focusing on alkene metathesis has been included prior to the discussion of carbene complexes of individual metals. The metal carbyne section has been organized according to reaction type.
Factors Affecting Purchase Intention of University‐Licensed Apparel

This study explores the factors that influence consumer's perceived value and purchase intentions toward university-licensed apparel among college students. Four factors were identified through the initial focus groups and literature review. Based on the value-intention framework, this study developed and empirically examined a structural model to investigate the effects of these factors upon consumers' perceived value and purchase intentions of university-licensed apparel. A convenience sample of 255 undergraduate students from a large university in the southeast were the source of data. The findings provide evidence of a causal relationship among school identification, peer influence, apparel product attributes, perceived value, and purchase intention. The findings contribute to an understanding of college students' behavior toward university-licensed merchandise. The findings suggest marketing directions for manufacturers, retailers, and university authorities.
The survival of water within extrasolar minor planets

We compute that extrasolar minor planets can retain much of their internal H2O during their host star’s red giant evolution. The eventual accretion of a water-rich body or bodies onto a helium white dwarf might supply an observable amount of atmospheric hydrogen, as seems likely for GD 362. More generally, if hydrogen pollution in helium white dwarfs typically results from accretion of large parent bodies rather than interstellar gas as previously supposed, then H2O probably constitutes at least 10% of the aggregate mass of extrasolar minor planets. One observational test of this possibility is to examine the atmospheres of externally polluted white dwarfs for oxygen in excess of that likely contributed by oxides such as SiO2. The relatively high oxygen abundance previously reported in GD 378 can be explained plausibly but not uniquely by accretion of an H2O-rich parent body or bodies. Future ultraviolet observations of white dwarf pollutions can serve to investigate the hypothesis that environments with liquid water that are suitable habitats for extremophiles are widespread in the Milky Way.
Modulational instability for nonlinear Schrödinger equations with a periodic potential

We study the stability properties of periodic solutions to the Nonlinear Schrodinger (NLS) equation with a periodic potential. We exploit the symmetries of the problem, in particular the Hamiltonian structure and the $\U(1)$ symmetry. We develop a simple sufficient criterion that guarantees the existence of a modulational instability spectrum along the imaginary axis. In the case of small amplitude solutions that bifurcate from the band edges of the linear problem this criterion becomes especially simple. We find that the small amplitude solutions corresponding to the band edges alternate stability, with the first band edge being modulationally unstable in the focusing case, the second band edge being modulationally unstable in the defocusing case, and so on. This small amplitude result has a nice physical interpretation in terms of the effective mass of a particle in the periodic potential. We also consider, in somewhat less detail, some sideband instabilities in the small amplitude limit. We find that, depending on the Krein signature of the collision, these can be of one of two types. Finally we illustrate this with some exact calculations in the case where $V(x)$ is an elliptic function, where all of the relevant calculations can be done explicitly.
Theoretical interpretation of photometric properties of the Martian surface and atmosphere

Earth-based UBV photometry, photographs from the Lowell Observatory, and Mariner 9 data are combined with a new radiative transfer theory to derive physical parameters for the Martian surface and atmosphere, both before and during the 1971 dust storm. Storm dust particles had a single scattering albedo of 0.84 plus or minus 0.02 and an asymmetry factor of 0.35 plus or minus 0.10 in green (V) light. The geometric albedo of Mars was 0.15 and the phase integral 1.83, yielding 0.27 for the Bond albedo. The mean optical thickness of the 'clear' atmosphere averaged over the whole planet was 0.15 plus or minus 0.05 and was not dependent on wavelength. Geometric albedos for the surface are 0.25 (light areas) and 0.17 (dark areas) in V, 0.095 in B, and 0.060 in U. The soil particles are moderately backward scattering with an asymmetry factor of minus 0.20, and therefore rather opaque. The mean surface roughness is 0.57, representing the depth/radius ratio of an average hole, and being only one-half as large as values typical for the moon and asteroids.
Bessel sequences of exponentials on fractal measures

Jorgensen and Pedersen have proven that a certain fractal measure ν has no infinite set of complex exponentials which form an orthonormal set in L2(ν). We prove that any fractal measure μ obtained from an affine iterated function system possesses a sequence of complex exponentials which forms a Riesz basic sequence, or more generally a Bessel sequence, in L2(μ) such that the frequencies have positive Beurling dimension.
THE FREQUENCY SPACE OF A FREE GROUP

We analyze the structure of the frequency spaceQ(F) of a nonabelian free group F = F(a1,…,ak) consisting of all shift-invariant Borel probability measures on ∂F and construct a natural action of Out(F) on Q(F). In particular we prove that for any outer automorphism ϕ of F the conjugacy distortion spectrum of ϕ, consisting of all numbers ‖ϕ(w)‖/‖w‖, where w is a nontrivial conjugacy class, is the intersection of ℚ and a closed subinterval of ℝ with rational endpoints.
Lorenz rankings of rules for the adjudication of conflicting claims

For the adjudication of conflicting claims, we develop three general approaches to obtain Lorenz rankings of rules. Our first approach concerns a parameterized family that contains several important rules (Thomson in Soc Choice Welf 31:667–692, 2008). We give a condition that the parameters defining two members of the family should satisfy for one of them to Lorenz dominate the other. Our second approach exploits the concept of “consistency” (Young in Math Oper Res 12:398–414, 1987). We derive a criterion to deduce Lorenz domination for arbitrarily many claimants from Lorenz domination in the two-claimant case. Our third approach is based on the notion of an “operator” on the space of rules (Thomson and Yeh in J Econ Theory 143:177–198, 2008). We develop conditions under which operators preserve the Lorenz order, or reverse it. As corollaries of our general theorems, we obtain rankings of most of the rules that have been discussed in the literature.