cssi/SciSciGPT-SciSciNet huggingface dataset:
A predictive-validity-based procedure for choosing between regression and equal weights.

Abstract The equal weighting procedure has often been found to have more predictive validity than regression. This paper makes use of estimators of the population cross-validated correlation to estimate the predictive validity of both regression and equal weights and to suggest a procedure for choosing between the two in any given situation.
Planetary mission departures from Space Station orbit

The concept of orbital assembly and launch of oversized planetary (or lunar) spacecraft from a Space Station is rapidly coming of age. This prospect raises a host of new problems demanding timely resolution. The one most serious issue involved in launch from a rapidly precessing Space Station orbit (about -7.2 deg/day) is the need to cope with the generally out-of-plane orientation of the V-infinity departure vector. Methods dealing with single or multiple injection maneuvers, deep space plane changes, nodal shift caused by reboost strategy modifications, and departure window duration analysis are discussed.
Copying out our ABCs - the role of gene redundancy in interpreting genetic hierarchies

Abstract The complete sequence of the Arabidopsis genome is scheduled to be determined by the end of the year 2000. While this goal could prove to be something of a moving target (the estimated size of the genome has grown from 120 Mb to 130 Mb over the last year 1 ), it is clear that the majority of genes required for higher plant growth, reproduction and development will have been described within this time frame. Some of the implications of this landmark achievement are already becoming clear, even though less than a half of the genome has been sequenced.
SmartID: a highly accurate physics-based isotope attribution algorithm

The spectral post-processing algorithm Advanced Synthetically Enhanced Detector Resolution Algorithm (ASEDRA (patent pending)) has shown to be a powerful tool for deconvolving full energy peaks from scintillation spectrometer-acquired gamma-ray spectra, effectively improving obtainable data-synthesized energy resolutions by a factor of four to six times over what is rendered from the detector. An isotope attribution algorithm, SmartID, was developed to augment ASEDRA in order to improve radionuclide identification accuracy. SmartID utilizes a novel, physics-based method of importance weighting the ASEDRA-identified peaks and the emissions of a candidate isotope. This methodology enhances the screening of potential false peaks and prevents isotope mismatches. As a final step, SmartID assigns a physical matching attribution score to each possible isotope match to reflect goodness-of-fit. A test suite of 105 gamma-ray spectra acquired with a 2"x2" NaI:T1 spectrometer under varying shielding conditions and various single and multi-source configurations were recorded for testing the accuracy of ASEDRA+SmartID. The sources utilized in the tests included 133 Ba, 109 Cd, 57 Co, 60 Co, 137 Cs, 152 Eu, 54 Mn, 22 Na, 232 Th, natural uranium rods and a PuBe source. Shielding configurations varied widely, ranging from none to more than 2.5cm Pb. Overall, SmartID proved to be more than 95% accurate in attributing the correct isotope(s) to the spectra.
High Order Correlation Tensors in Turbulence

High order correlation tensors for the spatial derivatives of the velocity field are studied with an emphasis on angular dependencies and sensitivity of these correlations to the effect of intermittency. In particular, it is found that the sum of longitudinal and transverse correlations of the deformation rates is proportional to the intermittency deviation from the classical scale similarity of velocity field. {copyright} {ital 1999} {ital The American Physical Society}
Unified complexity analysis for Newton LP methods

We show that a theorem of Smale can be used to unify the polynomial-time bound proofs of several of the recent interior algorithms for linear programming and convex quadratic programming.
Child-custody reform, marital investment in children, and the labor supply of married mothers

Abstract Research on child custody primarily focuses on the well-being of children following divorce. We extend this literature by examining how the prospect of joint child custody affects within-marriage investment in children through changes in household bargaining power. Variation in the timing of joint-custody reforms across states provides a natural-experiment framework with which to examine within-marriage investment in children. The probability of children's private school attendance declines by 12% in states that adopt joint-custody laws. We also find evidence linking joint-custody reform to higher rates of labor force participation for married mothers, which may indicate less time devoted household production.
An Analytic and Experimental Study of Multiple Channel Controllers

A multiple channel controller (MCC) is a controller which switches a given number of channels among a larger number of input/output devices and permits simultaneous access to as many devices as there are channels available. A simple queuing model for multiple channel controllers is created, and an approximate solution for this model is generated. The approximate solution is found, using simulation, to be very close for those cases examined to the actual behavior of the model. Further simulations indicate that the approximate solution of the model appears to be robust with respect to changes in some of the assumptions used in making the approximation. Trace data taken from a real system are analyzed and they confirm the predicted utility of MCC's. The problem of optimal scheduling of MCC's is briefly discussed. Alternative system configurations are compared with the objective of minimizing queuing delays.
Metallacyclopentane Formation: A Deactivation Pathway for a Tungsten(VI) Alkylidene Complex in Olefin Metathesis Reactions

W(NPh)[o-(Me3SiN)2C6H4](CH2CMe3)2, 2h, is quantitatively converted to a new metallacyclopentane complex, W(CH2CH2CH2CH2)(NPh)[o-(Me3SiN)2C6H4], 4, upon the addition of ethylene at T > 70 °C. The co...
The effect of ionizing radiation on dielectric properties of bovine achilles tendon collagen in the temperature range of thermal denaturation

The effect of γ-irradiation, with doses from 102−2×103 kGy, on the dielectric properties of solid-state collagen was studied. The temperature dependence of the constants ɛ′ and ɛ′' revealed a decrease in the denaturation temperature with increasing dose of irradiation. Dielectric dispersion observed in the frequency range 10 Hz to 10 kHz was suggested to be due to Maxwell-Wagner-Sillars polarization. In addition, an increase in the irradiation dose resulted in increasing activation energy of bovine achilles tendon collagen.
Casein Kinase 2 Regulates the NR2 Subunit Composition of Synaptic NMDA Receptors

N-methyl-D-aspartate (NMDA) receptors (NMDARs) play a central role in development, synaptic plasticity, and neurological disease. NMDAR subunit composition defines their biophysical properties and downstream signaling. Casein kinase 2 (CK2) phosphorylates the NR2B subunit within its PDZ-binding domain; however, the consequences for NMDAR localization and function are unclear. Here we show that CK2 phosphorylation of NR2B regulates synaptic NR2B and NR2A in response to activity. We find that CK2 phosphorylates NR2B, but not NR2A, to drive NR2B-endocytosis and remove NR2B from synapses resulting in an increase in synaptic NR2A expression. During development there is an activity-dependent switch from NR2B to NR2A at cortical synapses. We observe an increase in CK2 expression and NR2B phosphorylation over this same critical period and show that the acute activity-dependent switch in NR2 subunit composition at developing hippocampal synapses requires CK2 activity. Thus, CK2 plays a central role in determining the NR2 subunit content of synaptic NMDARs.
PERFORMANCE AS POLEMIC: TAIROV'S 1920 PRINCESS BRAMBILLA AT THE MOSCOW KAMERNY THEATRE

Aside from hinting at the rift between the two directors that had become evident after their failed 1918 collaboration on Claudel's The Exchange , Tairov's criticism of Meyerhold's The Dawn reveals a widening gap in the two directors’ fundamental conceptions of the purpose of theatre in the wake of the Revolution. Meyerhold famously declared “October in the theatre” after becoming head of the Theatre Department of Narkompros (the Commissariat of Enlightenment) in the fall of 1920; he attempted to liquidate the Moscow state academic theatres, of which the Kamerny was one, and to require that all theatres stage revolutionary works using the radical methods of “cubism, futurism and suprematism.” Although Tairov had experimented with cubist designs, he had spent his immediate post-Revolutionary years defending theatre as an autonomous art form that should express universal truths rather than being a vehicle for topical content, declaring, “A propagandist theatre after a revolution is like mustard after a meal.”
Comparison of effects of propranolol versus pindolol on sinus rate and pacing frequency in sick sinus syndrome

Beta blockers in patients with sick sinus syndrome (SSS) may prevent supraventricular arrhythmias, systemic hypertension and myocardial ischemia, but may cause excessive depression of sinus node function. In 8 patients with SSS and a permanent pacemaker, the effect of chronic oral pindolol on sinus rate and pacing frequency was compared with that of propranolol in a double-blind crossover trial. In all patients the pacemaker was programmed to a rate of < or = 50 beats/min. Holter monitors, obtained at baseline and on each drug, were used to calculate peak ambulatory sinus rate, number of paced beats per day, maximal number of paced beats per hour, and percentage of hours with paced beats. The peak sinus rate with pindolol therapy was 24% higher than with propranolol (p = 0.001). During pindolol therapy, the number of paced beats per day and maximal paced beats per hour were reduced 54% (p = 0.04) and 61% (p = 0.02), respectively, compared with propranolol. Patients with SSS who require beta-blocker therapy for tachycardia, systemic hypertension or angina pectoris may have less bradycardia when treated with pindolol rather than propranolol. Beta blockers like pindolol, which cause less sinus node depression, may obviate the need for prophylactic permanent pacemakers in patients with SSS, and may help to prevent chronotropic incompetence and pacemaker syndrome in patients already treated with a VVI device.
Detection of HLA restricted anti-minor histocompatibility antigen(s) reactive cells from skin GVHD lesions☆

Abstract Recipients of marrow grafts from HLA-identical, (including MLC non-reactive) sibling donors have a 40–50% incidence of acute graft vs. host disease (GVHD); the involvement of non-HLA linked, minor histocompatibility antigens (miHA) has been implicated. One of the target tissues of GVHD is the skin where morphological analysis of biopsy specimens is often used to support this diagnosis. We have obtained skin biopsy specimens from the site of GVHD lesions, grown the cells in the presence of T cell growth factor (TCGF) and feeder cells, and tested these cultured cells in the primed lymphocyte test (PLT) and cell mediated lympholysis (CML) assay. Five of six cell cultures tested demonstrated secondary proliferative but not cytolytic reactivity; cells from one culture demonstrated both reactivities. The cell culture populations generated are presumably directed against non-HLA antigens, i.e., miHA whose expression is restricted by an HLA antigen of the recipient. The data are consistent with the suggestion that in the majority of these cultures, the restriction element may be a determinant encoded within the HLA-D region: DQ, DR, and possibly DP based on panel testing. Although the number of cases is small, these preliminary data demonstrate the feasibility of thsi type of culturing system and also suggest that the cellular immunological events leading to the manifestation of skin GNHD lesions may be predominantly a delayed type hypersensitivity reaction.
Acoustic detection of a seafloor spreading episode on the Juan de Fuca Ridge using military hydrophone arrays

Until recently, no practical method has been available to continuously monitor seismicity of seafloor spreading centers. The availability of the U.S. Navy's SOund SUrveillance System (SOSUS) for environmental research has allowed the continuous monitoring of low-level seismicity of the Juan de Fuca Ridge in the northeast Pacific. On June 22, 1993, NOAA installed a prototype system at U.S. Naval Facility Whidbey Island to allow real-time acoustic monitoring of the Juan de Fuca Ridge using SOSUS. On June 26, 2145 GMT, a burst of low-level seismic activity, with accompanying harmonic tremor, was observed and subsequently located near 46°15′N, 129°53′W, on the spreading axis of the Juan de Fuca Ridge. Over the following 2 days, the activity migrated to the NNE along the spreading axis with the final locus of activity near 46°31.5′N, 129°35′W. The nature of the seismicity was interpreted to represent a lateral dike injection with the possibility of eruption on the seafloor. Based on this interpretation, a response effort was initiated by U.S. and Canadian research vessels, and both warm water plumes and fresh lavas were subsequently identified at the site.
Adenosine 5′-monophosphate-removing system in fructose-1,6-bisphosphatase assay mixture: A new approach

Abstract A simple new AMP-removing system for inclusion in the assay mixture of fructose-1,6-bisphosphatase is described. It consists of either AMP deaminase or 5′-nucleotidase, depending on the pH at which the activity of fructose-1,6-bisphosphatase is measured. This system takes advantage of the fact that AMP deaminase and 5′-nucleotidase irreversibly convert AMP to IMP and adenosine, respectively, both being inert to fructose-1,6-bisphosphatase. As compared with the widely used AMP-removing system of W. J. Black, A. Van Tol, J. Fernado, and B. L. Horecker (1972, Arch. Biochem. Biophys. 151 , 576–590), this new system is simpler and more versatile in application.
Determination of bake time and temperature of painted plastic using mathematical morphology and neural networks

This paper discusses a new automated image analysis technique for inspecting and monitoring changes in plastic bumper surfaces during the paint-baking process. This new technique produces excellent performance, and is appropriate for on-line production monitoring as well as laboratory analysis. The objective of this work was to develop an accurate method for determining the paint bake time and temperature at which parts had been treated. This task was accomplished using mathematical morphology to extract differentiating features from samples collected at three magnifications and sending these feature-vectors to a back-propagation neural network for classification.
Molecular Recognition of tRNA by tRNA Pseudouridine 55 Synthase

Escherichia coli tRNA pseudouridine 55 synthase catalyzes pseudouridine formation at U55 in tRNA. A 17 base oligoribonucleotide analog of the T-arm was equivalent to intact native tRNA as a substrate for pseudouridine 55 synthase, viz., the features for substrate recognition by this enzyme are completely contained within the T-arm. The structures and activities of mutant tRNAs and T-arms were used to analyze substrate recognition by pseudouridine 55 synthase. The 17-mer T-arm was an excellent substrate for the synthase, while disruption of the stem structure of the 17-mer T-arm eliminated activity. Kinetic data on tRNA mutants lacking single T-stem base pairs indicated that only the 53:61 base pair, which maintains the 7 base loop size, was essential for activity. The identities of individual bases in the stem were unimportant provided base pairing was intact. A major function of the T-stem appears to be the maintainence of a stable stem-loop structure and proper presentation of the T-loop to pseudouridine 55 synthase. The 7 base T-loop could be expanded or contracted by 1 base and still retain activity, albeit with a 30-fold reduction in kcat. Kinetic analysis of T-loop mutants revealed the requirement for U54, U55, and A58, and a preference for C over U at position 56. Base substitutions at loop nonconserved position 59 or semiconserved positions 57 or 60 were well tolerated. Comparison of pseudouridine 55 synthase and tRNA (m5U54)-methyltransferase revealed that both enzymes required the stem-loop structure. However, pseudouridine 55 synthase was not stringent for a 7 base loop and recognized a consensus base sequence within the T-loop, while tRNA (m5U54)-methyltransferase recognized the secondary structure of the 7 member T-loop with only a specific requirement for U54, the T-loop substrate site. We conclude that recognition of tRNA by pseudouridine 55 synthase resides in the conformation of the T-arm plus four specific bases of the loop.
Scheduling of testing tasks and resource planning in new product development using stochastic programming

Abstract Testing is a crucial step in new product development in many industrial sectors, from microelectronics to the automotive industry. In the pharmaceutical sector, specifically, candidate drugs have to undergo clinical trials, a process that takes 2–4 years and costs hundreds of millions of dollars. In this paper we are concerned with the scheduling of clinical trials and the planning of the resources necessary to carry these trials out. We present a stochastic programming (SP) framework that addresses the two problems simultaneously. To address large problems we develop a number of results and methods. First, we exploit the structure of the problem to reduce the number of pairs of scenarios for which non-anticipativity has to be enforced, and the number of binary variables. Second, we develop a finite-horizon approximation that allows us to formulate problems using fewer stages without compromising the quality of the solution. Third, we take advantage of the sequential nature of the testing process to develop a smaller but tighter mixed-integer programming (MIP) formulation; we show that a relaxation of this formulation can be used to obtain feasible and most often optimal solutions over the stages of interest. Finally, we develop a rolling-horizon-based approach, where the decisions of the relaxed problem are used over few early periods determining how and when uncertainty will be realized, and a new problem is formulated and solved as we move forward in time.
Transfer of the tumor inducing factor in Agrobacterium tumefaciens.

Summary The Crown-gall tumor inducing factor in Agrobacterium tumefaciens bacterial strain C-58 may be removed by culture at 36°C and it can be reintroduced by inoculation into tomato tumors previously induced by the virulent strain TT-133-1.
Errata for Computing the Top Betti Numbers of Semialgebraic Sets Defined by Quadratic Inequalities in Polynomial Time

For any l>0, we present an algorithm which takes as input a semi-algebraic set, S, defined by P 1≤0,…,P s ≤0, where each P i ∈R[X 1,…,X k ] has degree≤2, and computes the top l Betti numbers of S, b k−1(S),…,b k−l (S), in polynomial time. The complexity of the algorithm, stated more precisely, is $\sum_{i=0}^{\ell+2}{s\choose i}k^{2^{o(\min(\ell,s))}}$. For fixed l, the complexity of the algorithm can be expressed as $s^{\ell+2}+k^{2^{O(\ell)}}$, which is polynomial in the input parameters s and k. To our knowledge this is the first polynomial time algorithm for computing nontrivial topological invariants of semialgebraic sets in R k defined by polynomial inequalities, where the number of inequalities is not fixed and the polynomials are allowed to have degree greater than one. For fixed s, we obtain, by letting l=k, an algorithm for computing all the Betti numbers of S whose complexity is $k^{2^{O(S)}}$.
Dinoflagellate Evolution: Speculation and Evidence*†

Nuclear features of dinoflagellates that were used originally to support the Mesocaryota concept are reviewed. The fibrillar diameter of dinoflagellage chromatin, low level of chromosomal basic proteins, membrane attachment of chromosomes and swirl pattern observed in sectioned chromosomes are features that support a prokaryotic affinity. The presence of repeated and highly complex DNA, a S-phase of DNA synthesis in the cell cycle, presence of basic proteins, and the reinterpretation of extranuclear microtubules as a spindle support the contention that dinoflagellates are eukaryotes. This combination of prokaryotic and eukaryotic features suggests that dionflagellates are a geologically old group and that perhaps they diverged from the higher eukaryotic lineage before evolution of eukaryotic chromatin but after the evolution of repeated DNA. The 2 patterns of carotenoid composition exemplified by the presence of peridinin or fucoxanthin suggest separate origins of dinoflagellate plastids, perhaps by prokaryotic and eukaryotic capture. It is suggested that the species possessing fucoxanthin obtained their plastids by capture of photosynthetic eukaryotes.
Identifying Malicious Metering Data in Advanced Metering Infrastructure

Advanced Metering Infrastructure (AMI) has evolved to measure and control energy usage in communicating through metering devices. However, the development of the AMI network brings with it security issues, including the increasingly serious risk of malware in the new emerging network. Malware is often embedded in the data payloads of legitimate metering data. It is difficult to detect malware in metering devices, which are resource constrained embedded systems, during time-critical communications. This paper describes a method in order to distinguish malwarebearing traffic and legitimate metering data using a disassembler and statistical analysis. Based on the discovered unique characteristic of each data type, the proposed method detects malicious metering data. (i.e. malwarebearing data). The analysis of data payloads is statistically performed while investigating a distribution of instructions in traffic by using a disassembler. Doing so demonstrates that the distribution of instructions in metering data is significantly different from that in malware-bearing data. The proposed approach successfully identifies the two different types of data with complete accuracy, with 0% false positives and 0% false negatives.
Direct Interaction of Focal Adhesion Kinase with p190RhoGEF

Focal adhesion kinase (FAK) is a protein-tyrosine kinase that associates with multiple cell surface receptors and signaling proteins through which it can modulate the activity of several intracellular signaling pathways. FAK activity can influence the formation of distinct actin cytoskeletal structures such as lamellipodia and stress fibers in part through effects on small Rho GTPases, although the molecular interconnections of these events are not well defined. Here, we report that FAK interacts with p190RhoGEF, a RhoA-specific GDP/GTP exchange factor, in neuronal cells and in brain tissue extracts by co-immunoprecipitation and co-localization analyses. Using a two-hybrid assay and deletion mutagenesis, the binding site of the FAK C-terminal focal adhesion targeting (FAT) domain was identified within the C-terminal coiled-coil domain of p190RhoGEF. Binding was independent of a LD-like binding motif within p190RhoGEF, yet FAK association was disrupted by a mutation (Leu-1034 to Ser) that weakens the helical bundle structure of the FAK FAT domain. Neuro-2a cell binding to laminin increased endogenous FAK and p190RhoGEF tyrosine phosphorylation, and co-transfection of a dominant-negative inhibitor of FAK activity, termed FRNK, inhibited lamininstimulated p190RhoGEF tyrosine phosphorylation and p21 RhoA GTP binding. Overexpression of FAK in Neuro-2a cells increased both endogenous p190RhoGEF tyrosine phosphorylation and RhoA activity, whereas these events were inhibited by FRNK co-expression. Because insulin-like growth factor 1 treatment of Neuro-2a cells increased FAK tyrosine phosphorylation and enhanced p190RhoGEF-mediated activation of RhoA, our results support the conclusion that FAK association with p190RhoGEF functions as a signaling pathway downstream of integrins and growth factor receptors to stimulate Rho activity.
Accessory hemi diaphragm.

Abstract Background/purpose Accessory hemi diaphragm (AHD) is an uncommon condition. Its clinical features, diagnosis and management have not been clearly defined. Methods We reviewed the world literature and added a case of our own. Results There are 40 proven cases in the literature. The lesion occurs almost exclusively in the right hemithorax. Twenty seven cases presented with cardiovascular and/or respiratory symptoms while 3 had symptoms pertaining to other systems. In the remaining 10 patients the diagnosis was either made accidentally or information pertaining to their presentation is missing. Abnormalities of pulmonary and systemic blood vessels often accompany the abnormality. The diagnosis is usually suspected because of an abnormal chest radiograph and confirmed by a variety of tests. Conclusions If the AHD prevents proper aeration of the lung it should be excised. If vascular abnormalities coexist they should be treated along with the AHD. Asymptomatic patients may be observed after confirming the diagnosis.
Types of pelvic exenterations: A reappraisal

Subgrouping of pelvic exenterations as supralevator (type I), infralevator (type II), with vulvectomy (type III), and, an added category, extended can be helpful to facilitate communication when referring to these patients. It also can facilitate a more detailed analysis of operative risk factors, complications, and results and can increase our knowledge of the indications and limitations of the different exenterative procedures.
Effects of age on GM1 ganglioside-induced recovery of concentrations of dopamine in the striatum in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice.

Abstract The effect of GM 1 ganglioside on the recovery of concentrations of dopamine (DA) in the striatum, following administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), was studied in mice of various ages. At the start of the study, the mice were 8 weeks, 6, 12 and 20 months old. Mice from each age group received MPTP for 5 days, followed by either GM 1 ganglioside or saline for 4 or 8 weeks. Animals older than 8 weeks, that did not receive GM, showed no spontaneous recovery of striatal levels of DA in the striatum, over either 4 or 8 weeks. Animals that received GM 1 showed varied amounts of recovery of levels of DA in the striatum. The young animals (8 wk old) had the most pronounced effect from GM 1 . With increasing age, the magnitude of the effect of GM 1 became attenuated and recovery had a longer latency. The results suggest that GM 1 can be effective in at least partially restoring MPTP-depleted levels of DA in the striatum, even in aged mice.
Microanalysis of ceramics with PIXE and LA-ICP-MS

Abstract The provenance postulate states that artifact raw material sources can be determined by chemical characterization as long as between-source chemical differences exceed within-source variation. For ceramics, successful differentiation of sources usually requires the measurement of a large suite of elements. While laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) can provide concentration data for nearly every element whose concentration is at or above 100 ng/g, it requires the use of “matrix matched” standards for quantitative analysis. In this work, we report on the use of micro-PIXE to develop standards for the microanalysis of ceramics by LA-ICP-MS.
Telematics: safe and fun driving

The author describes current and future wireless applications that are likely to become our companions in future journeys. This article shows how the concept of personal vehicles has changed in the last decades. Our vehicles will become not only a safe and comfortable means of transportation but also a digital platform for entertainment and access to a vast quantity of information while traveling.
Can bedside oculomotor (HINTS) testing differentiate central from peripheral causes of vertigo

Editor’s Note: Emergency physicians must often make decisions about patient management without clear-cut data of sufficient quality to support clinical guidelines or evidence-based reviews. Topics in the Best Available Evidence section must be relevant to emergency physicians, are formally peer reviewed, and must have a sufficient literature base to draw a reasonable conclusion but not such a large literature base that a traditional “evidence-based” review, meta-analysis, or systematic review can be performed.
Composition and species diversity of pine-wiregrass savannas of the Green Swamp, North Carolina

Fire-maintained, species-rich pine-wiregrass savannas in the Green Swamp, North Carolina were sampled over their natural range of environmental conditions and fire frequencies. Species composition, species richness, diversity (Exp H’, 1/C), and aboveground production were documented and fertilization experiments conducted to assess possible mechanisms for the maintenance of high species diversity in these communities.
US—Mexico fresh vegetable trade: the effects of trade liberalization and economic growth

Abstract Studies of US–Mexico vegetable trade have generally emphasized the importance of US tariffs in determining the competitive advantage of US producers. Even so, research has identified at least four factors related primarily to the different levels of economic development in the US and Mexico that also have important effects on US–Mexico agricultural trade in general and fresh vegetable trade in particular. These include the differential growth rates of US and Mexican real wages, production technology (yields), and per capita income as well as cyclical movements in the real Mexican Peso/US Dollar exchange rate. This study examines the relative contribution of NAFTA and the development-related factors to likely future changes in US fresh vegetable imports from Mexico. The analysis employs an econometric simulation model of US and Mexican markets for five fresh vegetables (tomatoes, cucumbers, squash, bell peppers, and onions) accounting for 80% of US fresh vegetable imports. The results suggest that the 1994–1995 Peso devaluation rather than NAFTA was primarily responsible for the sharp increase in US imports of Mexican vegetables observed in the first years following the implementation of NAFTA. Over time, however, the results suggest that differences in the growth rates of US and Mexican production yields and, to a lesser extent, of US and Mexican real incomes and/or real wage rates could plausibly contribute more to the future growth of US tomato, squash, and onion imports from Mexico than the trade liberalizing effects of NAFTA.
Promoting Statistical Analysis in the Marketing Curriculum: A Conjoint Analysis Exercise

The paper presents a detailed class assignment for learning how to perform and interpret conjoint analysis using dummy variable regression. To reduce “statistics anxiety,” the problem is simplified by representing products in terms of five attributes, each with two levels. To enhance student interest and class discussion, the conjoint problem centers on off-campus summer school courses, and students provide their own evaluations, allowing them to estimate their own part worths. The student questionnaire is provided as well as a complete set of assignment questions, discussion of answers, and recommendations for adapting the assignment to serve different learning objectives. The paper addresses two gaps that have been noted in the marketing education literature.
Effect of seed layer on biaxial texturing of pulsed laser deposited YSZ films on electrodeposited Ir/Ni–W tapes

Abstract Pulsed laser deposition (PLD) of biaxially textured Y 2 O 3 stabilized ZrO 2 (YSZ) layers on electrodeposited Ir/Ni–W tape is reported. Biaxial texturing is obtained by deposition of an YSZ seed layer at 800 °C in 10 −6 Torr vacuum. X-ray diffraction (XRD) studies of θ –2 θ and pole figures confirmed in-plane, out-of-plane biaxial texturing with Δ ϕ = 8° and Δ ω = 7.9°. Atomic force microscopy (AFM) revealed a surface with roughness of about 3 nm.
Purposes and Perceptions: What Do University Mathematics Professors See as Their Role in the Education of Secondary Mathematics Teachers?.

The content coursework of preservice secondary mathematics teachers (PSMTs) is a current topic of concern in both the mathematics and education fields. There is a need to determine the knowledge and dispositions necessary to teach secondary mathematics and how coursework can help PSMTs develop the appropriate knowledge and dispositions. In response, this study sought the perceptions on PSMTs' knowledge and dispositions from mathematics teachers who typically teach PSMTs. In addition, mathematics professors were asked how upper-level mathematics coursework could contribute to PSMTs learning of desired knowledge and dispositions. Results provide a picture of what professors articulate as important to preservice secondary mathematics teacher training and perceptions of their role in supporting the PSMTs' training. Implications for preservice teacher education and cross-department collaboration are discussed.
A Web site to promote CS education as a research area

This paper introduces a Web site designed as a tool for anyone wanting to carry out research in the area of CS education. The paper describes the motivation behind the various parts of the site and invites participation from the SIGCSE community in using the site and helping it evolve. The Web site highlights many possibilities for solid educational research and thus publicizes the field as a legitimate academic endeavor.
Synthesis of monodispersed silica powders I. Particle properties and reaction kinetics

Abstract Currently there are several models discussed to describe the formation of monodispersed silica particles by the controlled hydrolysis and condensation of tetraethylorthosilicate (TEOS) in mixtures of water/ammonia and ethanol. The present study will show results on an extended range of experimental conditions. Particle growth followed a first-order reaction kinetic with respect to TEOS concentration. Reaction orders for the ammonia and water content were 0·97 and 1·18, respectively. Only monomeric (≈ 70–90%) and dimeric (≈ 10–25%) silicate units were detected during the growth reaction and an activation energy of 27 kJ mol−1 (6·5 kcal mol−1) was indicated. Particles revealed an ultramicroporous internal structure. A narrower size distribution and a more spherical shape were observed at higher water concentrations. The results suggested an aggregation mechanism of nanometer-sized primary nuclei during the first stage of the reaction followed by a monomer addition growth mechanism thereafter.
Suggestion for a charge-state “enforcer” for heavy ion accelerators

Abstract The design of a new type of device, a charge-state “enforcer”, is described. This device, using an intense magnetic field with some static or rf electric field deflection, causes the stripping of a beam of heavy ions into a single selected charge state with nearly 100% efficiency. The requirements and limitations of the device are discussed.
Kinetics of lipoprotein lipase activity: effects of the substrate apoprotein on reaction velocity.

Abstract 1. In the absence of the substrate lipoprotein protein moiety, lipoprotein lipase activity with synthetic triglyceride and partial glyceride substrates was under control of ionisable groups, with p K values of 6.8 and 9.1. The enthalpy of ionisation of the former was 5500 cal/mole. Reaction of an ionisable group with p K = 8.0 was also indicated. 2. The incorporation of delipidated very low density lipoprotein protein with the lipid substrate increased the maximal reaction velocity of lipase activity at all hydrogen ion concentrations, and also decreased the apparent Michaelis constant of the reaction at alkaline pH. 3. Lipoprotein protein also induced a shift in the alkaline limb of the plot of maximal reaction velocity vs pH, and apparent Michaelis constant vs pH, p K values in the presence of cofactor protein were 7.0 and 9.8 with indicated reaction also of a group with p K = 8.8. 4. Similar p K values were obtained with lipoprotein lipase purified from post-heparin plasma, and from adipose tissue.
Nucleoside free energy perturbation calculations: mutation of purine-to-pyrimidine and pyrimidine-to-purine nucleosides

Free energy perturbation calculations were conducted on the mutations of pyrimidine-to-pyrimidine, purine-to-purine, purine-to-pyrimidine, and pyrimidine-to-purine nucleosides. The parameters and technique required for these perturbations is presented. Each of the four nucleosides in DNA were mutated into the other three nucleosides, and the calculated change in free energy for each of the 12 mutations is reported.
Relationship between expression of epidermal growth factor and simian virus 40 T antigen in a line of transgenic mice

The pattern of expression of the simian virus 40 (SV40) T antigen gene and resultant dysplasia were re-examined in a line of transgenic mice in which the T antigen gene was under the control of the SV40 early promoter. We found that T antigen expression in the kidney, and resulting dysplastic lesions, occurred exclusively in the distal convoluted tubules and the ascending limbs of Henle. Epidermal growth factor (EGF) expression in the kidney of normal mice was similarly immunolocalized. The correlation between high EGF immunoreactivity in normal mouse tissues and T antigen expression in the transgenic counterpart was also seen in the choroid plexus epithelium and in the submandibular glands of male mice. T antigen was not found in the submandibular gland of transgenic females. Similarly, EGF was only rarely detected in the normal female submandibular gland. In contrast to the correlation between T antigen expression in the transgenic mice and EGF expression in the corresponding tissues of the normal mice, within the dysplastic lesions of the transgenic mice EGF expression was severely diminished. Adenocarcinomas of the male submandibular gland from another line of transgenic mice that expresses theInt-1 transgene, showed similarly reduced levels of immunostaining for EGF. Thus, reduced expression of EGF might be a general feature of dysplasia and tumorigenesis in those tissues that normally express EGF.
Directions for disaster nursing education in the United States

Because of their diverse education, experience, and practice settings, nurses are uniquely qualified to be first receivers, care givers, and leaders in any large-scale public health emergency. Many nurses, however, continue to feel inadequately prepared to function effectively in these types of situations. Great strides have been made since 2001, but much work remains to be accomplished. This article focuses on newer approaches used to teach nurses the principles of disaster preparedness. It also addresses the need to incorporate mass casualty care and disaster management skills into undergraduate curricula, continuing nurse education, and advanced degree programs for nurses in the United States.
High-peak-power efficient edge-emitting photonic crystal nanocavity lasers.

Record-high edge-emitted peak power was collected from L3 and finite-waveguide two-dimensional photonic crystal nanocavity quantum well membrane lasers at room temperature under single-mode operations. Peak power levels of 230 μW and 540 μW were collected from L3 and finite-waveguide edge-emitters, and their quantum differential efficiencies are 11% and 27%, respectively, limited by their collection efficiencies in free space.
Design and Testing of an Advanced Implantable Neuroprosthesis With Myoelectric Control

An implantable stimulator-telemeter (IST-12) was developed for applications in neuroprosthetic restoration of limb function in paralyzed individuals. The IST-12 provides 12 stimulation channels and two myoelectric signal (MES) channels. The MES circuitry includes a two-channel multiplexer, preamplifier, variable gain amplifier/bandpass filter, full-wave rectifier, and bin integrator. Power and control signals are transmitted from an external control unit to the IST-12 through an inductive link. Recorded MES signals are telemetered back to the external control unit through the same inductive link. Following bench testing, one device was implanted chronically in a dog for 15 months and evaluated. Conditions were identified in which MES could be recorded with minimal stimulus artifact. The ability to record MES in the presence of stimulation was verified, confirming the potential of the IST-12 to be used as a myoelectric controlled neuroprosthesis.
Russian Religious Rejections of Money and Homo Economicus: The Self-Identifications of the “Pioneers of a Money Economy” in Post-Soviet Russia

Russian Orthodoxy, Christian Socialism, and Russian Communism are consistent in their denunciation of Homo Economicus - the Western ideal type celebrating individual proprieties and instrumental rationality. Russian religious and cultural rejections of Homo Economicus and Western-style contract are counterpoised by the constructions of Homo Orthodox and Russian covenant, that exalt communitarianism and transcendental value convictions. The recent market-style reforms in Russia brought the rising tide of Westem influences. Focusing on new Russian bankers who are representative of the spirit of an emerging marketplace, this paper explores their self-identifications as Homo Orthodox or Homo Economicus, and their endorsements of covenant or contract. Based on the interviews with sixty-one Russian bankers, it is concluded that the perceptions of the pioneers of a money economy deviate from traditional Russian cultural-religious ideals questioning the endurance of these ideals in the new market situation
T-cell receptors for cytokines: Targets for immunotherapy of leukemia/lymphoma

Summary Background: Cytokine receptors are exceptionally valuable targets for immunotherapy. For example, the high affinity IL-2 receptor is expressed by abnormal T cells in patients with certain lymphoid malignancies or autoimmune disorders and in individuals rejecting allografts whereas it is not expressed by normal resting cells. Design: To exploit this difference in receptor expression in normal resting cells and leukemic cells we have introduced different forms of IL-2 receptor directed therapy including an unmodified murine antibody to the a subunit of the IL-2 receptor (anti-Tac), humanized anti-Tac as well as this antibody armed with truncated Pseudomonas exotoxin or a- and Pemitting radionuclides (e.g., 211 At and 90 Y). In particular, unmodified murine anti-Tac was used in the therapy of HTLV-Iassociated adult T-cell leukemia (ATL). Results: Six of nineteen patients treated with this antibody underwent a partial (four) or complete (two) remission. In a subsequent clinical trial involving anti-Tac armed with 90 Yover 50% of the patients with ATL treated underwent a partial or complete remission. Conclusions: New agents under development include humanized antibodies directed toward shared cytokine receptors such as IL-2/15RP used by both IL-2 and IL-15 as well as to a shared signal transduction element Jak3 utilized by the T-cell stimulatory cytokines IL-2, IL-4, IL-7, IL-9 and IL-15. Thus our emerging understanding of cytokine receptors and their signaling pathways taken in conjunction with the ability to produce humanized antibodies armed with radionuclides or toxins are providing novel perspectives for the treatment of leukemia and lymphoma.
Near optimum universal belief propagation based decoding of LDPC codes and extension to turbo decoding

In this paper, we propose a normalized belief propagation-based algorithm which utilizes normalization to improve the accuracy of the soft values delivered by a previously proposed simplified belief propagation-based algorithm, and can achieve an error performance very close to that of belief propagation. We also extend the principle of normalization to improve the performance of the Max-Log-MAP algorithm in turbo decoding.
Therapeutic angiogenesis the new electrophysiology

Approximately 15 million patients suffer from coronary and peripheral atherosclerotic diseases in the United States alone.1 The evolving development of medical and surgical therapies has significantly improved the physician’s ability to manage these patients, yet many continue to suffer debilitating symptoms from their disease and remain at risk for myocardial infarction, limb loss, and death. This clinical imperative, coupled with rapid advances in molecular biology, has led to the exploration of a plethora of therapeutic angiogenesis strategies. A method described in this issue of Circulation 2 offers yet another means by which angiogenesis may be achieved and thus potentially opens a new chapter in the ongoing search for novel approaches for the treatment of ischemia. In placing the novelty of the approach by Kanno et al into perspective, it is worth considering the important advances made during the last decade in the field of therapeutic angiogenesis. The investigators at the forefront of this field have not used a traditional pharmaceutical approach to search for potential angiogenic agents effective against vascular disease. Instead, they have chosen to arm themselves with the fruits of the molecular biology revolution by harnessing the power of endogenous human angiogenic factors. Vascular endothelial growth factor (VEGF) is the most potent and specific endogenous angiogenic factor yet identified, so it makes sense that it would have drawn the attention of cardiologists interested in angiogenic therapies. The demonstration that intra-arterial injection of recombinant VEGF could induce collateral formation in ischemic rabbit hindlimbs3 suggested that VEGF would be a useful angiogenic agent, and this has subsequently been confirmed by an impressive corpus of preclinical data. Phase I and II clinical trials are now under way to test the effects of VEGF in patients with ischemic vascular disease, and preliminary results from some of these trials have been …
Modeling acreage response with risk consideration: The case of estate tobacco in Malawi

Abstract Employing a simple econometric model with risk consideration, the behavior of Malawi's estate or commercial farmers is investigated. The results indicate that commercial farmers are both price responsive and risk-averse. The short- and long-run price elasticity estimates are 0.33 and 0.91, respectively. The response to price risk is −0.11, in the short-run and −0.30, in the long run. These estimates imply an inelastic but significant response. The analysis has also demonstrated the extent of bias in parameter estimates and overall model performance associated with the omission of risk variables.
Entrepreneurship: An Integrating Typology and Evaluation of the Empirical Research in the Field

Entrepreneurship is one of the newest research fields in management. Most of the empirical research has been completed in the last decade. Other disciplines have made significant contributions to the field. An integrating framework and typology were formulated by Wortman (1986b). Against that framework and typology, this review has examined most of the empirical research in the past decade. Significant shifts in the nature and scope of the field and in research design, methods, and statistics used have occurred. Proposed research studies and questions are primarily in the exploratory stages of the development of a new field. Little of the research has been disseminated to entrepreneurs.