cssi/SciSciGPT-SciSciNet huggingface dataset:
Chilling requirements of hazelnut cultivars

Abstract Chilling requirements of catkins, female inflorescences, and vegetative buds of 45 genotypes of Corylus avellana L. and 13 genotypes of other Corylus species and interspecific hybrids were estimated by cutting shoots in the field at weekly intervals and forcing them in a warm greenhouse for 4 weeks. Chilling requirements were lowest for catkins and highest for leaf buds, and ranged from less than 100 to 860 h for catkins, 290–1550 h for female flowers, and 365–1690 h for leaf buds. The lowest chilling requirements were observed for the leading C. avellana cultivars of Turkey and southern Italy. The yellow-leafed ornamental C. avellana cultivar ‘Aurea’ had very high chilling requirements for all plant parts. Chilling requirements of vegetative buds of clones heterozygous for the non-dormant trait were less than those of clones homozygous for the dormant allele. Chilling requirements were comparable or slightly higher for three groups of other Corylus species, but were considerably higher for all plant parts of Corylus cornuta var. californica . Time of catkin elongation, stigma exsertion, and leaf bud swell in the field were highly and positively correlated with estimated chilling requirements of these plant parts. The chilling requirements of female inflorescences and vegetative buds were highly correlated. Genotypes with the same estimated chilling requirement leafed out as much as 3 weeks apart in the field, indicating differences in post-rest heat requirements.
Have returns to education changed in Nigeria? Uncovering the role of democratic reforms

There is documented evidence that returns to education were low during the military rule of the 1990s in Nigeria. In this paper, I investigate the claim that after democracy in 1999, there have been increases in the returns to education. In addition, I examine the possible role of democratic reform in explaining this time difference in return. Following the sudden death of military general Sanni Abacha, Nigeria moved to democracy in 1999, ending a 15-year stretch of military rule. This move was followed by significant institutional and economic reforms, which could lead to changes in returns to education. The average return to education before and after 1999 is estimated using instrumental variables, and consistent estimates of the change in return are derived. The results provide evidence that returns to education have increased in Nigeria after 1999. More importantly, I show that reforms implemented after democracy in Nigeria can explain a significant part of this increase in returns to education although we cannot completely rule out other secondary factors. Further, evidence is provided that the wage reform implemented after democracy plays a significant role in explaining the higher increases in returns for government workers and those with tertiary education, in comparison to others. Copyright 2011 , Oxford University Press.
CIRCULAR RIBBON FLARES AND HOMOLOGOUS JETS

Solar flare emissions in the chromosphere often appear as elongated ribbons on both sides of the magnetic polarity inversion line (PIL), which has been regarded as evidence of a typical configuration of magnetic reconnection. However, flares having a circular ribbon have rarely been reported, although it is expected in the fan-spine magnetic topology involving reconnection at a three-dimensional (3D) coronal null point. We present five circular ribbon flares with associated surges, using high-resolution and high-cadence H{alpha} blue wing observations obtained from the recently digitized films of Big Bear Solar Observatory. In all the events, a central parasitic magnetic field is encompassed by the opposite polarity, forming a circular PIL traced by filament material. Consequently, a flare kernel at the center is surrounded by a circular flare ribbon. The four homologous jet-related flares on 1991 March 17 and 18 are of particular interest, as (1) the circular ribbons brighten sequentially, with cospatial surges, rather than simultaneously, (2) the central flare kernels show an intriguing 'round-trip' motion and become elongated, and (3) remote brightenings occur at a region with the same magnetic polarity as the central parasitic field and are co-temporal with a separate phase of flare emissions. In another flare onmore » 1991 February 25, the circular flare emission and surge activity occur successively, and the event could be associated with magnetic flux cancellation across the circular PIL. We discuss the implications of these observations combining circular flare ribbons, homologous jets, and remote brightenings for understanding the dynamics of 3D magnetic restructuring.« less
Use of VHDL synthesis in an advanced digital design course

A very-high-speed integrated-circuit hardware description language (VHDL) synthesis tool from Viewlogic is being used in an advanced digital design course. The tool has the capability of synthesizing sequential elements (flip-flops) as well as combinational logic. The tool gives students the capability of practicing a true top-down design methodology. Synthesis implementation targets used were the ITD standard cell library (Oct-tools), the Xilinx field programmable gate array (FPGA), the Actel FPGA, and the Altera FPGA. The addition of the Viewlogic VHDL simulation/synthesis tool and the FPGA mapping software has significantly enhanced the advanced digital design course. It allows students to evaluate tradeoffs between standard cell, Xilinx, Altera, and Actel implementations. >
A Unified Point Process Probabilistic Framework to Assess Heartbeat Dynamics and Autonomic Cardiovascular Control

In recent years, time-varying inhomogeneous point process models have been introduced for assessment of instantaneous heartbeat dynamics as well as specific cardiovascular control mechanisms and hemodynamics. Assessment of the model’s statistics is established through the Wiener-Volterra theory and a multivariate autoregressive (AR) structure. A variety of instantaneous cardiovascular metrics, such as heart rate (HR), heart rate variability (HRV), respiratory sinus arrhythmia (RSA), and baroreceptor-cardiac reflex (baroreflex) sensitivity (BRS), are derived within a parametric framework and instantaneously updated with adaptive and local maximum likelihood estimation algorithms. Inclusion of second-order non-linearities, with subsequent bispectral quantification in the frequency domain, further allows for definition of instantaneous metrics of non-linearity. We here present a comprehensive review of the devised methods as applied to experimental recordings from healthy subjects during propofol anesthesia. Collective results reveal interesting dynamic trends across the different pharmacological interventions operated within each anesthesia session, confirming the ability of the algorithm to track important changes in cardiorespiratory elicited interactions, and pointing at our mathematical approach as a promising monitoring tool for an accurate, non-invasive assessment in clinical practice. We also discuss the limitations and other alternative modeling strategies of our point process approach.
Metallicity Gradients and Gas Flows in Galaxy Pairs

We present the first systematic investigation into the metallicity gradients in galaxy close pairs. We determine the metallicity gradients for eight galaxies in close pairs using H II region metallicities obtained with high signal-to-noise multi-slit observations with the Keck LRIS Spectrograph. We show that the metallicity gradients in close pairs are significantly shallower than gradients in isolated spiral galaxies such as the Milky Way, M83, and M101. These observations provide the first solid evidence that metallicity gradients in interacting galaxies are systematically different from metallicity gradients in isolated spiral galaxies. Our results suggest that there is a strong relationship between metallicity gradients and the gas dynamics in galaxy interactions and mergers.
A New SiC‐Whisker‐Reinforced Lithium Aluminosilicate Composite

The glass-ceramic matrix of the well-known lithium aluminosilicate (LAS)/SiC composite is usually formulated near the spodumene composition. We report here a new composition which is rich in alumina (78 wt%) and lean in silica (21 wt%) and lithia (1 wt%). This formulation offers a new option of converting the glass-ceramic matrix to a mullite/alumina matrix upon annealing above 1400"C, and hence better creep resistance and other high-temperature mechanical properties. Using a transient-phase processing method that we developed previously for the superplastic forming of mullite, we are able to hot-press a composite containing 30 vol% Sic whiskers at -1350°C to achieve full density. Flexural strength measurements up to 1400°C have confirmed the improved high-temperature strength and creep resistance over conventional LAS. The fracture toughness is also higher than that of LAS. The results suggest that the new composition may be chosen as a better candidate matrix for Sic-fiber-reinforced composites.
Neuro-Ophthalmologic Emergencies

This article is designed to provide the emergency physician with the knowledge necessary for the diagnosis and management of the more common neuro-ophthalmologic emergencies. Emphasis is placed on the recognition and initial evaluation of neuro-ophthalmologic disease.
Designing informative securities

We create a formal framework for the design of informative securities in prediction markets. These securities allow a market organizer to infer the likelihood of events of interest as well as if he knew all of the traders' private signals. We consider the design of markets that are always informative, markets that are informative for a particular signal structure of the participants, and informative markets constructed from a restricted selection of securities. We find that to achieve informativeness, it can be necessary to allow participants to express information that may not be directly of interest to the market organizer, and that understanding the participants' signal structure is important for designing informative prediction markets.
Necessary and sufficient conditions for the solvability of the L p Dirichlet problem on Lipschitz domains

We study the homogeneous elliptic systems of order $$2\ell$$ with real constant coefficients on Lipschitz domains in $$\mathbb{R}^n$$ , $$n\ge 4$$ . For any fixed p > 2, we show that a reverse Holder condition with exponent p is necessary and sufficient for the solvability of the Dirichlet problem with boundary data in L p . We also obtain a simple sufficient condition. As a consequence, we establish the solvability of the L p Dirichlet problem for $$n\ge 4$$ and $$2-\epsilon< p<\frac{2(n-1)}{n-3} +\epsilon$$ . The range of p is known to be sharp if $$\ell\ge 2$$ and $$4\le n\le 2\ell + 1$$ . For the polyharmonic equation, the sharp range of p is also found in the case n = 6, 7 if $$\ell=2$$ , and $$n=2\ell+2$$ if $$\ell\ge 3$$ .
Wireless scheduling with hybrid ARQ

A model for downlink wireless scheduling is studied, which takes into account both user-channel conditions and retransmissions with packet combining hybrid [automatic repeat request (ARQ)]. Quality-of-service (QoS) requirements for each user are represented by a cost function, which is an increasing function of queue length. The objective is to find a scheduling rule that minimizes the average cost over time. We consider two scenarios: 1) the cost functions are linear, and packets arrive to the queues according to a Poisson process and 2) the cost functions are increasing, convex, and there are no new arrivals (draining problem). In each case, we transform the system model into a different model that fits into a framework for stochastic scheduling developed by Klimov. Applying Klimov's results, we show that the optimal schedulers for the transformed models in both scenarios are specified by fixed priority rules. Applying the inverse transformation in each case gives the optimal scheduling policy for the original problem. The priorities can be explicitly computed, and in the first scenario, are given by simple closed-form expressions. For the draining problem, we show that the optimal policy never interrupts the retransmissions of a packet. We also show that a simple myopic scheduling policy, called the U'R rule, performs very close to the optimal scheduling policy in specific cases. We present numerical examples, which compare the performance of the optimal scheduling rule with several heuristic rules.
Magnetoconvection and thermal coupling of the Earth's core and mantle

Numerical calculations of finite amplitude magnetoconvection in a rotating spherical shell are used to investigate the thermal coupling of the Earth’s core to the mantle. From the observed distribution of lower mantle seismic velocity heterogeneity we construct a pattern of heat flow on the core-mantle boundary consisting of a spherical average q 0 plus heterogeneity with amplitude Δ q For Δ q / q 0 = 0, corresponding to a homogeneous lower mantle, convection in the presence of a strong toroidal magnetic field consists of nearly axisymmetric magnetostrophic flow inside the inner-core tangent cylinder and a single large-scale spiraling columnar plume outside the tangent cylinder. Interaction of the columnar plume with the toroidal field induces patches of radial magnetic field distributed symmetrically with respect to the equator. For Δ q / q 0 = 10, corresponding to a strongly heterogeneous lower mantle, stably stratified regions develop below warm mantle and enhanced convection develops below cold mantle. This modulation of the convection pattern breaks the columnar structure of core motions and destroys the equatorial symmetry of the induced magnetic field, without locking it to the mantle. Our results indicate that mantle structure is of secondary importance, compared with rotation, in controlling the structure of the geomagnetic field.
Essential and redundant rules in Horn knowledge bases

A production rule of a knowledge base is called essential if it is present in any prime knowledge base which is logically equivalent to the given one. Identification of essential rules constitutes a crucial part of the structural analysis of any knowledge base. It specifies the degree of freedom we have in constructing logically equivalent transformations of the base, by specifying the set of rules which must remain in place, and implicitly showing which rules could be replaced by other ones. A prime rule is called redundant if it is not present in any irredundant prime knowledge base which is logically equivalent to the given one. Redundant rules can be viewed as the “least important” prime rules of a knowledge base. The recognition of redundancy of a particular prime rule in a knowledge base will eliminate such rule from consideration in any future simplifications of the knowledge base. This paper provides combinatorial characterization of essential and redundant rules of propositional Horn knowledge bases, and develops, whenever possible, efficient computational procedures for recognizing essentiality and redundancy of prime rules of Horn knowledge bases.
WHAT HAPPENS AT THE HORIZON

The Schwarzschild metric has an apparent singularity at the horizon r = 2M. What really happens there? If physics at the horizon is "normal" laboratory physics, then we run into Hawking's information paradox. If we want nontrivial structure at the horizon, then we need a mechanism to generate this structure that evades the "no hair" conjectures of the past. Further, if we have such structure, then what would be the role of the traditional black hole metric which continues smoothly past the horizon? Recent work has provided an answer to these questions, and in the process revealed a beautiful tie-up between gravity, string theory and thermodynamics.
The Politics of Parental Involvement: How Opportunity Hoarding and Prying Shape Educational Opportunity

As more state legislatures join the debate on school-choice and parent-trigger legislation, their discussions draw attention to an evolving landscape outside school walls where parental action shapes educational opportunity. Parents wield their political, social, economic, and cultural capital to secure the best educational outcomes for their children. This paper identifies the political frames that distinguish the educational opportunity-seeking behavior of middle-, working-, and lower-class parents. Rational choice and interest group theories are used to explain the politics of middle-class opportunity hoarding by way of tracking and school-choice practices. Policy entrepreneurship and interest group theory provide the frameworks to explain the support for vouchers and parent-trigger laws by lower- and working-class parents as part of their opportunity-prying efforts.
Exploring Class Discussions from a Massive Open Online Course (MOOC) on Cartography

The rise of the Massive Open Online Course (MOOC) has led to its application in Cartographic education. Students in these classes generate enormous amounts of text data in the form of discussion forum posts. Here we explore the topics and geographic references found in over 95,000 forum posts collected during the 2013 launch of Maps and the Geospatial Revolution, a MOOC taught on Coursera. Using Phrase Nets, topic modeling methods, and a named-entity extraction geocoding tool, we show how students describe their use of maps, what key topics drove conversations during the class, and the geography associated with placenames mentioned in posts. These results help shed light on how novices use and understand Cartography and show how places found in discussion forum text reflect the global reach of MOOCs.
Migration and Hedonic Valuation: The Case of Air Quality

Abstract Conventional hedonic techniques for estimating the value of local amenities rely on the assumption that households move freely among locations. We show that when moving is costly, the variation in housing prices and wages across locations may no longer reflect the value of differences in local amenities. We develop an alternative discrete-choice approach that models the household location decision directly, and we apply it to the case of air quality in US metro areas in 1990 and 2000. Because air pollution is likely to be correlated with unobservable local characteristics such as economic activity, we instrument for air quality using the contribution of distant sources to local pollution—excluding emissions from local sources, which are most likely to be correlated with local conditions. Our model yields an estimated elasticity of willingness to pay with respect to air quality of 0.34–0.42. These estimates imply that the median household would pay $149–$185 (in constant 1982–1984 dollars) for a one-unit reduction in average ambient concentrations of particulate matter. These estimates are three times greater than the marginal willingness to pay estimated by a conventional hedonic model using the same data. Our results are robust to a range of covariates, instrumenting strategies, and functional form assumptions. The findings also confirm the importance of instrumenting for local air pollution.
On luminous blue variables as the progenitors of core-collapse supernovae, especially Type IIn supernovae

Luminous blue variable (LBV) stars are very massive, luminous, unstable stars that suffer frequent eruptions. In the last few years, these stars have been proposed as the direct progenitors of some core-collapse supernovae (SNe), particularly Type IIn SNe, in conflict with stellar evolution theory. In this paper we investigate various scenarios wherein LBV stars have been suggested as the immediate progenitors of SNe. Many of these suggestions stem from the fact that the SNe appear to be expanding in a high-density medium, which has been interpreted as resulting from a wind with a high mass-loss rate. Others arise due to perceived similarities between the SN characteristics and those of LBVs. Only in the case of SN 2005gl do we find a valid possibility for an LBV-like progenitor. Other scenarios encounter various levels of difficulty. The evidence that points to LBVs as direct core-collapse SNe progenitors is far from convincing. High mass-loss rates are often deduced by making assumptions regarding the wind parameters, which are contradicted by the results themselves. A high density need not necessarily imply a high wind mass-loss rate: wind shocks sweeping up the surrounding medium may give a high-density shell with a low associated wind mass-loss rate. High densities may also arise due to wind clumps, or due to a previous LBV phase before the SN explodes as a WolfRayet (WR) star. Some Type IIn SNe appear to signify more a phase in the life of an SN than a class of SNe, and may arise from more than one type of progenitor. A WR phase that lasts for a few thousand years or less could be one of the more probable progenitors of Type IIns, and channels for creating short-lived WR phases are briefly discussed.
Lithium Methyl Carbonate as a Reaction Product of Metallic Lithium and Dimethyl Carbonate

To improve the understanding of passive film formation on metallic lithium in organic electrolyte, we synthesized and characterized lithium methyl carbonate (LiOCO{sub 2}CH{sub 3}), a prototypical component of the film. The chemical structure of this compound was characterized with Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR), and its thermal stability and decomposition pathway was studied by thermo-gravimetric analysis (TGA). The FTIR spectrum of chemically synthesized compound enabled us to resolve multiple products in the passive film on lithium in dimethyl carbonate (DMC). Lithium methyl carbonate is only one of the components, the others being lithium oxalate and lithium methoxide.
Synthesis of Heterosubstituted Hexaarylbenzenes via Asymmetric Carbonylative Couplings of Benzyl Halides

[structure: see text]. Asymmetric carbonylative couplings of benzyl halides have been shown to give heterosubstituted 1,3-diarylacetones in moderate to high yields. These asymmetric ketones were converted via Knoevenagel condensations to tetraarylcyclopentadienones, and further conversion via dehydro-Diels-Alder cycloadditions gave highly heterofunctionalized hexaarylbenzenes with uniquely functionalized aryl groups at the para positions of the central benzene. This method allows control of the substituents on each of four unique pendent aryl group positions, giving rise to substitution patterns not available using symmetrical 1,3-diarylacetones.
Continuous flow multi-step organic synthesis

Using continuous flow techniques for multi-step synthesis enables multiple reaction steps to be combined into a single continuous operation. In this mini-review we discuss the current state of the art in this field and highlight recent progress and current challenges facing this emerging area.
Electron beam stability and beam peak to peak motion data for NSLS X-ray storage ring

In the past two years, a significant reduction in electron beam motion has been achieved at the NSLS X-ray storage ring. The implementation of global analog orbit feedbacks, based on a harmonics correction scheme, has reduced the beam motion globally. Implementation of six local analog feedback systems has reduced the beam motion even further at the corresponding beam line straight sections. This paper presents beam motion measurements, showing the improvement due to the feedback systems. Beam motion is measured using a spectrum analyzer and data is presented at various frequencies, where peaks were observed. Finally, some of the beam motion sources are discussed. >
Non-invasive haemoglobin measurement in patients undergoing elective Caesarean section

Background The ability to measure haemoglobin (Hb) real-time and non-invasively offers important clinical value in the assessment of acute changes in maternal Hb during the peripartum period. This study evaluates the Masimo Rainbow SET ® Radical-7 Pulse CO-Oximeter in a pregnant population undergoing Caesarean section (CS). Methods Fifty patients undergoing elective CS were enrolled in this prospective, controlled study and followed for 48 h after surgery. Non-invasive Masimo Hb (SpHb) values were compared with laboratory Hb values from venous blood samples drawn at baseline, immediately post-CS, and 24 h post-CS using the Bland–Altman plots. Longitudinal analysis of SpHb changes over time was performed using mixed-effects regression modelling. Results For the comparison between SpHb and laboratory Hb, SpHb displayed a significant positive bias at baseline {1.22 g dl −1 [95% confidence interval (CI): 0.89–1.54]} and at 24 h post-CS [1.36 g dl −1 (95% CI: 1.04–1.68)]. The bias immediately post-CS was 0.14 g dl −1 (95% CI: −0.18 to 0.46). The limits of agreement at baseline, immediately post-CS, and at 24 h post-CS were: −0.9 and 3.33, −2.35 and 2.56, and −0.55 and 3.27 g dl −1 , respectively. The mean decrease in SpHb from baseline to 48 h post-CS was ∼1 g dl −1 . Conclusions The variability in bias and limits of agreements of the Rainbow SET ® Radical-7 Pulse CO-Oximeter SpHb may limit its clinical utility for assessing Hb concentration in patients undergoing elective CS. Modifications are needed in the calibration of the device to improve accuracy and precision in an obstetric setting. The study was registered at clinicaltrials.gov (NCT01108471) before participant enrolment: URL=http://clinicaltrials.gov/ct2/show/NCT01108471?term=butwick&rank=1.
A point process framework for modeling electrical stimulation of the auditory nerve

Model-based studies of responses of auditory nerve fibers to electrical stimulation can provide insight into the functioning of cochlear implants. Ideally, these studies can identify limitations in sound processing strategies and lead to improved methods for providing sound information to cochlear implant users. To accomplish this, models must accurately describe spiking activity while avoiding excessive complexity that would preclude large-scale simulations of populations of auditory nerve fibers and obscure insight into the mechanisms that influence neural encoding of sound information. In this spirit, we develop a point process model of individual auditory nerve fibers that provides a compact and accurate description of neural responses to electric stimulation. Inspired by the framework of generalized linear models, the proposed model consists of a cascade of linear and nonlinear stages. We show how each of these stages can be associated with biophysical mechanisms and related to models of neuronal dynamics. Moreover, we derive a semianalytical procedure that uniquely determines each parameter in the model on the basis of fundamental statistics from recordings of single fiber responses to electric stimulation, including threshold, relative spread, jitter, and chronaxie. The model also accounts for refractory and summation effects that influence the responses of auditory nerve fibers to high pulse rate stimulation. Throughout, we compare model predictions to published physiological data of response to high and low pulse rate stimulation. We find that the model, although constructed to fit data from single and paired pulse experiments, can accurately predict responses to unmodulated and modulated pulse train stimuli. We close by performing an ideal observer analysis of simulated spike trains in response to sinusoidally amplitude modulated stimuli and find that carrier pulse rate does not affect modulation detection thresholds.
Reconciling Observed Tariffs and the Median Voter Model

Median voter theory applied to trade policy predicts positive tariffs in capital-abundant countries and negative tariffs in labor-abundant countries. Negative tariffs are rare, and this paper reconciles the median voter theory with observed protectionism across countries. By considering large countries, I show the optimal tariff is a sum of the median voter component and a positive term of trade component. Positive terms of trade effects raise tariffs in all countries, and can overcome the negative median voter component in labor-abundant countries. Testing the tariff prediction with cross-section and panel data from the 1990s, I show the median voter component is negative in labor-abundant countries and positive in capital-abundant countries. As expected, terms of trade effects raise tariffs across all countries and are stronger among nonmembers of the WTO.
Iterations of quadratic polynomials over finite fields

Given a map f:Z-->Z and an initial argument alpha, we can iterate the map to get a finite set of iterates modulo a prime p. In particular, for a quadratic map f(z)=z^2 +c, c constant, work by Pollard suggests that this set should have length on the order of p^(1/2). We give a heuristic argument that suggests that the statistical properties of this set might be very similar to the Birthday Problem random variable X_n, for an n=p day year, and offer considerable experimental evidence that the limiting distribution of these set lengths, divided by p^(1/2), for p\leq x as x goes to infinity, converges to the limiting distribution of X_n/n^(1/2), as n goes to infinity.
Safety of Alternate Day Fasting and Effect on Disordered Eating Behaviors

Alternate day fasting (ADF; ad libitum intake “feed day” alternated with 75% restriction “fast day”), is effective for weight loss, but the safety of the diet has been questioned. Accordingly, this study examined occurrences of adverse events and eating disorder symptoms during ADF. Obese subjects (n = 59) participated in an 8-week ADF protocol where food was provided on the fast day. Body weight decreased (P < 0.0001) by 4.2 ± 0.3%. Some subjects reported constipation (17%), water retention (2%), dizziness (<20%), and general weakness (<15%). Bad breath doubled from baseline (14%) to post-treatment (29%), though not significantly. Depression and binge eating decreased (P < 0.01) with ADF. Purgative behavior and fear of fatness remained unchanged. ADF helped subjects increase (P < 0.01) restrictive eating and improve (P < 0.01) body image perception. Therefore, ADF produces minimal adverse outcomes, and has either benign or beneficial effects on eating disorder symptoms.
Nitrogen in Agricultural Systems: Implications for Conservation Policy

Nitrogen is an important agricultural input that is critical for crop production. However, the introduction of large amounts of nitrogen into the environment has a number of undesirable impacts on water, terrestrial, and atmospheric resources. This report explores the use of nitrogen in U.S. agriculture and assesses changes in nutrient management by farmers that may improve nitrogen use efficiency. It also reviews a number of policy approaches for improving nitrogen management and identifies issues affecting their potential performance. Findings reveal that about two-thirds of U.S. cropland is not meeting three criteria for good nitrogen management. Several policy approaches, including financial incentives, nitrogen management as a condition of farm program eligibility, and regulation, could induce farmers to improve their nitrogen management and reduce nitrogen losses to the environment.
Narrating data structures: the role of context in CS2

Learning computing with respect to the context of its use has been linked in previous reports to student motivation in introductory CS courses. In this report, we consider the role of context in a second course. We present a case study of a CS2 data structures class that uses a media computation context. In this course, students learn data structures and object-oriented programming through a pervasive narrative about how real media professionals use data structures to model the real world and to construct the digital images, sounds, and animations with which the students are familiar in their daily lives. We found that context played a different role in a second course than in a first course. We found evidence that some students did not need context to appreciate computing, but we also found evidence that context can help students get engaged with the material that they otherwise do not find interesting. In particular, the narrative aspect of a context may help students in relating the elements of the course and may even help with learning.
Avant Healthcare: Building Competitive Advantages From Customer Service

This case examines the importance of customer service in the modern economy. In order to do so, it presents the findings from a case study on Avant Healthcare. In-depth interviews were conducted with two executives from the firm and then the interviews were systemically analyzed. The results give a clear example of how firms can build competitive advantages from customer service.
Oxacalixarenes and oxacyclophanes containing 1,8-naphthyridines: a new class of molecular tweezers with concave-surface functionality.

The first examples of oxacalix[4]arenes and [14]oxacyclophanes bearing 1,8-naphthyridine units are reported, and these systems function as molecular tweezers containing inner-cavity hydrogen bond acceptors.
Quantum Deconstruction of a 5D SYM and its Moduli Space

We deconstruct the fifth dimension of the 5D SYM theory with SU(M) gauge symmetry and Chern-Simons level kcs = M and show how the 5D moduli space follows from the non-perturbative analysis of the 4D quiver theory. The 5D coupling h = 1/g25 of the un-broken SU(M) is allowed to take any non-negative values, but it cannot be continued to h< 0 and there are no transitions to other phases of the theory. The alternative UV completions of the same 5D SYM — via M theory on the 3/2M orbifold or via the dual five-brane web in type IIB string theory — have identical moduli spaces: h ≥ 0 only, and no flop transitions. We claim these are intrinsic properties of the SU(M) SYM theory with kcs = M.
A high phase-space density mixture of 87 Rb and 133 Cs: towards ultracold heteronuclear molecules

We report the production of a high phase-space density mixture of 87Rb and 133Cs atoms in a levitated crossed optical dipole trap as the first step towards the creation of ultracold RbCs molecules via magneto-association. We present a simple and robust experimental setup designed for the sympathetic cooling of 133Cs via interspecies elastic collisions with 87Rb. Working with the |F = 1,mF = +1〉 and the |3, +3〉 states of 87Rb and 133Cs respectively, we measure a high interspecies three-body inelastic collision rate ∼10−25−10−26 cm6 s−1 which hinders the sympathetic cooling. Nevertheless by careful tailoring of the evaporation we can produce phase-space densities near quantum degeneracy for both species simultaneously. In addition we report the observation of an interspecies Feshbach resonance at 181.7(5) G and demonstrate the creation of Cs2 molecules via magneto-association on the 4(g)4 resonance at 19.8 G. These results represent important steps towards the creation of ultracold RbCs molecules in our apparatus.
Palladium-catalyzed asymmetric allylic alkylation of 3-aryloxindoles with allylidene dipivalate: a useful enol pivalate product.

Asymmetric allylic alkylation (AAA)[1] is a powerful and versatile method for the catalytic, asymmetric construction of quaternary stereocenters.[2] In the Mo- and Pd-AAA in particular, a broad range of functionalized electrophiles has been utilized, enabling the rapid synthesis of complex molecules in an atom- and step-economical manner.[3,4] Geminal dicarboxylates (e.g., allylidene dicarboxylates) constitute an under-explored set of electrophiles in this area.[5]
Autonomous exoskeleton reduces metabolic cost of human walking

Passive exoskeletons that assist with human locomotion are often lightweight and compact, but are unable to provide net mechanical power to the exoskeletal wearer. In contrast, powered exoskeletons often provide biologically appropriate levels of mechanical power, but the size and mass of their actuator/power source designs often lead to heavy and unwieldy devices. In this study, we extend the design and evaluation of a lightweight and powerful autonomous exoskeleton evaluated for loaded walking in (J Neuroeng Rehab 11:80, 2014) to the case of unloaded walking conditions. The metabolic energy consumption of seven study participants (85 ± 12 kg body mass) was measured while walking on a level treadmill at 1.4 m/s. Testing conditions included not wearing the exoskeleton and wearing the exoskeleton, in both powered and unpowered modes. When averaged across the gait cycle, the autonomous exoskeleton applied a mean positive mechanical power of 26 ± 1 W (13 W per ankle) with 2.12 kg of added exoskeletal foot-shank mass (1.06 kg per leg). Use of the leg exoskeleton significantly reduced the metabolic cost of walking by 35 ± 13 W, which was an improvement of 10 ± 3% (p = 0.023) relative to the control condition of not wearing the exoskeleton. The results of this study highlight the advantages of developing lightweight and powerful exoskeletons that can comfortably assist the body during walking.
Control of the Unsteady Flow in a Stator Blade Row Interacting With Upstream Moving Wakes

A computational approach, based on a spectral-element Navier-Stokes solver, has been applied to the study of the unsteady flow arising from wake-stator interaction. Direct, as well as turbulence-model calculations, provide insight into the mechanics of the unsteady flow and demonstrate the potential for controlling its effects. The results show that the interaction between the wakes and the stator blades produces a characteristic pattern of vortical disturbances, which have been correlated to the pressure fluctuations. Within the stator passage, the wakes migrate toward the pressure surface where they evolve into counterrotating vortices. These vortices are the dominant source of disturbances over the pressure surface of the stator blade. Over the suction surface of the stator blade, the disturbances are due to the distortion and detachment of boundary layer fluid. They can be reduced by tailoring the blade loading or by applying nonuniform suction
Cubic Liquid-Crystalline Nanoparticles

Cubic liquid-crystalline nanoparticles prepared from aqueous dispersions of cubic lipid-water phases are kinetically stable in the presence of certain dispersing agents. The properties of cubic nanoparticles from monoolein-water and other lipid-water systems have been examined with a variety of experimental techniques. The cubic nanoparticles can be stabilized by polymerization of the reactive lipids in cubic lipid assemblies. Several low-energy-input methods have been developed to facilitate the production and application of cubic nanoparticles. The ability to incorporate and deliver lipophilic, amphiphilic, and water-soluble molecules in a controlled manner and the good biocompatibility of cubic nanoparticles make them excellent candidates for drug-delivery applications.
An Electro-Optical Shift Register

An electro-optical shift register composed only of electroluminescent (EL) and photoconductive (PC) cells was designed and successfully operated. While its measured operating speed probably does not make this shift register currently competitive in high-speed applications, it is amenable to construction in an extremely small volume, and has certain other unique characteristics.
Victory and Defeat in a Model of Behavior in Games and Toward Risk

The standard expected utility model is augmented by allowing individuals to receive additional utility in states in which they consider themselves victorious and to lose a utility increment in which they consider themselves defeated. The resulting event-dependent expected utility model is used to explain behavior in games and toward risk. In games, players consider themselves defeated when their monetary payoffs are low compared to their opponents' payoffs, and they consider themselves victorious when their payoffs are high, but not too high, compared to their opponents' payoffs. Under these conditions the model can accommodate behavior that has been interpreted elsewhere as inequity aversion, as well as cooperation in the prisoner's dilemma and in public good provision games. In situations of risk, individuals consider themselves victorious (defeated) when they receive an unlikely, avoidable, high (low) outcome. Under these conditions the model can accommodate such behavior as the Allais paradox, boundary effects, and simultaneous gambling and insurance.
Rate-distortion optimal fast thresholding with complete JPEG/MPEG decoder compatibility

We show a rate-distortion optimal way to threshold or drop the DCT coefficients of the JPEG and MPEG compression standards. Our optimal algorithm uses a fast dynamic programming recursive structure. The primary advantage of our approach lies in its complete compatibility with standard JPEG and MPEG decoders. >
The Jones polynomial and graphs on surfaces

The Jones polynomial of an alternating link is a certain specialization of the Tutte polynomial of the (planar) checkerboard graph associated to an alternating projection of the link. The Bollobas-Riordan-Tutte polynomial generalizes the Tutte polynomial of graphs to graphs that are embedded in closed oriented surfaces of higher genus. In this paper we show that the Jones polynomial of any link can be obtained from the Bollobas-Riordan-Tutte polynomial of a certain oriented ribbon graph associated to a link projection. We give some applications of this approach.
The single antenna interferometer

Air- and space-borne platforms using synthetic aperture radars (SAR) have made interferometric measurements by using either two physical antennas mounted on one air-frame or two passes of one antenna over a scene. A new interferometric technique using one pass of a single-antenna SAR system is proposed and demonstrated on data collected by the NASA-JPL AirSAR. Remotely sensed L-band microwave data are used to show the sensitivity of this technique to ocean surface features and provide a baseline for comparison with work by others using two-antenna systems. >
In Defence of the Anarchist

Mark Murphy contends that, whatever the merits of any philosophical argument for anarchism, most people are obligated to obey the law. Murphy defends a moral argument designed to show that most people in reasonably just political communities are obligated to obey the law. And he advances epistemological arguments calculated to support two key claims. First, people who believe they are obligated to obey the law are entitled to retain their belief in the face of anarchist criticism. Second, a credible account of political obligation can accommodate the concerns that drive anarchist arguments in such a way that no anarchist argument against political obligation could, in principle, be successful. I argue that Murphy's moral argument yields relatively limited results, and that his epistemological arguments do not succeed in showing that anarchists could not convict folk-believers in political obligation of unreasonableness.
Social Choice in the Development of Advanced Information Technology

Application of advanced information technology willprofoundly effect the nature of clerical, professional and managerial work. When these consequences are unplanned, they sometimes are positive and sometimes negative, in human and organizational terms. Referring to the range and importance of these impacts, the author argues why social criteria should be employed in the design and implementation of this new technology. Then, based on the increasingly flexible nature of the technology and its cost profile, he argues why social criteria can be applied without economic sacrifice. Turning to trends in social values, theories of management, and interests of trade unions, the author concludes that social criteria probably will be applied increasingly in the development of information technology in the United States. Finally, the paper reviews some of the methodological issues which will arise in the process.
Toward the development of metal-based synthetic nucleases and peptidases: a rationale and progress report in applying the principles of coordination chemistry

Abstract Recently there has been great interest in designing small metal complexes which are capable of catalytically hydrolyzing deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein. In this review, we attempt to justify this goal, as well as discuss some of the strategies currently being pursued. In addition, because much of the work is based on a few well-studied enzymatic hydrolases and exchange-inert metal complexes, the mechanisms proposed for these systems will also be briefly discussed, with special attention being paid to the relevance of these systems to the design of synthetic metallohydrolases. However, since the ultimate goal is not only to design an efficient hydrolase, but also to completely understand the mechanism, this review will generally be limited to labile metal complexes for which the coordination geometry is known and detailed kinetic and/or mechanistic information is available.
Metal–Organic Frameworks as Biomimetic Catalysts

In this Minireview, we have summarized the recent progress of biomimetic catalysis in the field of metal-organic frameworks (MOFs) with a focus on the implantation of biomimetic active sites into a stable MOF. In addition, the potential of creating highly selective catalytic pockets and diffusion-favored hierarchical structures in MOFs has also been explored. Furthermore, we have highlighted the achievements of MOF catalysts in the applications as mimics of peroxidase, cytochromes P450, hemoglobin, and photosynthetic systems.
Open pattern matching for C

Pattern matching is an abstraction mechanism that can greatly simplify source code. We present functional-style pattern matching for C++ implemented as a library, called Mach71. All the patterns are user-definable, can be stored in variables, passed among functions, and allow the use of class hierarchies. As an example, we implement common patterns used in functional languages.Our approach to pattern matching is based on compile-time composition of pattern objects through concepts. This is superior (in terms of performance and expressiveness) to approaches based on run-time composition of polymorphic pattern objects. In particular, our solution allows mapping functional code based on pattern matching directly into C++ and produces code that is only a few percent slower than hand-optimized C++ code.The library uses an efficient type switch construct, further extending it to multiple scrutinees and general patterns. We compare the performance of pattern matching to that of double dispatch and open multi-methods in C++.
A Technique For Measuring Vertically And Horizontally Polarized Microwave Brightness Temperatures Using Electronic Polarization-basis Rotation

This technique for electronically rotating the polarization basis of an orthogonal-linear polarization radiometer is based on the measurement of the first three feedhorn Stokes parameters, along with the subsequent transformation of this measured Stokes vector into a rotated coordinate frame. The technique requires an accurate measurement of the cross-correlation between the two orthogonal feedhorn modes, for which an innovative polarized calibration load was developed. The experimental portion of this investigation consisted of a proof of concept demonstration of the technique of electronic polarization basis rotation (EPBR) using a ground based 90-GHz dual orthogonal-linear polarization radiometer. Practical calibration algorithms for ground-, aircraft-, and space-based instruments were identified and tested. The theoretical effort consisted of radiative transfer modeling using the planar-stratified numerical model described in Gasiewski and Staelin (1990).