cssi/SciSciGPT-SciSciNet huggingface dataset:
Temporal Yield Variability under Conventional and Alternative Management Systems

Year to year variation in yield is an inherent risk associated with crop production and many growers rely on intensive mechanical or chemical inputs to preserve crop yield in the face of fluctuating environmental conditions. However, as interest grows in alternative crop management systems which depend less on external inputs, determining the degree to which management systems can impact the temporal yield variability will help the development of sustainable agroecosystems. This study assessed average crop yields and temporal yield variability over a 12-yr period in four agricultural management systems that are part of a long-term cropping systems experiment at the W.K. Kellogg Biological Station (KBS) Long Term Ecological Research (LTER) site in southwestern Michigan. The four systems follow a corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and winter wheat (Triticum aestivum L.) 3-yr rotation under conventional (CT), no-till (NT), low-input (LI), or organic (ORG) management, and each crop phase was present in the rotation four times from 1993 to 2004. Yields were measured each year and crop yield variability was estimated using the coefficient of variation calculated separately for each crop phase. Averaged over the study period, yields in the CT and NT systems were similar across all crop phases of the rotation and of higher magnitude than the LI system only in the winter wheat phase of the rotation. Compared to the other three management systems, yields in the ORG system were lower in the corn and winter wheat phases of the rotation. Yields in the soybean phase were similar across the four management systems. Temporal yield variability differed among management systems and rotation phases and was highest in the ORG system during the soybean (CV = 48%) and winter wheat (CV = 33%) phases of the rotation. Compared to the CT system, yield variability was 40% lower in the LI (corn phase), 33% lower in the NT (soybean phase) and similar in the NT (corn and winter wheat phases) systems. Results of this study suggest that yield and temporal yield variability under alternative management systems such as no-till and low-input can be comparable to that in conventional systems. However, temporal yield variability can be as high or higher in organic cropping systems without external inputs of manure or compost.
Equatorial Currents at Semi-Annual Period in the Indian Ocean

Abstract Moored records of zonal velocity in the western equatorial Indian Ocean are dominated by motion of semi-annual period. The motion is coherent over an array spanning more than 1000 km along the equator, 160 km across the equator, and 500 m in the vertical The signal has an amplitude of 0.15 m s−1. It has zonal, vertical and meridional length scales which are long compared to the dimensions of the array, and it shows upward propagation of phase. Behavior is characteristic of an eastward propagating equatorial Kelvin wave and a westward long equatorial Rossby wave. The vertical wavelength is an estimated 5000 m, implying an equatorial trapping scale of 400 km. Zonal wavelengths are ∼8000 km for the equatorial Rossby wave and 24000 km for the equatorial Kelvin wave. A downward energy flux, estimated to be 3 × 1016 erg s−1, most likely represents propagation away from surface forcing by the zonal wind.
Toward Improved Verification And Certification of Legacy Systems

Existing standards for dependable systems, and in particular DO-178B for commercial flight software and DO-254 for flight hardware, are best suited to “clean sheet of paper” designs for entirely new systems. Yet, in industry – and in particular for safety-critical systems – entirely new designs are relatively rare, and generally entail very high risks in both financial and performance terms. This paper briefly surveys the state of the art in methods for certifying legacy (or COTS) systems, and proposes improved procedures for the future, including the increased use of formal verification methods to enhance dependability. As standards evolve, these procedures may ameliorate the very high current cost and risk associated with present compliance requirements.
Autoimmune polyendocrinopathy-candidosis syndrome (APECS): Clinical variation, inheritance and HLA association in 40 Finnish patients

At present age of 8-59 years the manifestation was most variable ranging from life-long mild mucocutaneous affection to 4-fold endocrinopathy. The components are of 3 sorts. 1. Ectodermal dystrophy (nails, enamel, hair, cornea, oral mucosa) proved to be independent of endocrinopathy. 2. Cellular immunodefect appeared as chronic candidosis of oral and vaginal mucosa, nails and skin, and anergy to tuberculin and candida. 3. Autoimmune destruction led to hypoparathyroidism (32 patients), Addison's disease (22), female (6/13) and male (2/8) hypogonadism, pernicious anemia (5), diabetes (3) and hypothyroidism (1). No component was constant. Distribution of ancestors' birth places showed an accumulation at 5 rural areas, indicating involvement of a rare gene. Family pattern fitted to autosomal recessive gene (proportion of affected sibs 0.21-0.27 by different methods). Association was significant with HLA A3 (gene frequency 0.53 in contrast to 0.28 in healthy sibs and general population), but not with chromosome 6. The clinical variation appears to be independent of HLA.
Relative H-atom and O-atom concentration measurements in a laminar, methane/air diffusion flame

Relative H-atom and O-atom concentration profiles have been measured in a laminar, coflowing methane/air diffusion flame burning at atmospheric pressure. Multiphoton ionization (2+1 process at 243 nm) has been used to detect H atoms, while laser-induced fluorescence at 845 nm excited by two-photon absorption at 226 nm was employed to observe O atoms. In both cases it was found that low photon intensities (≤2×108 W/cm2) were required in order to avoid the photolytic production of the species of interest. Doppler-free measurements were carried out using a retroreflected-beam geometry in order to provide sufficient signal levels. Under these experimental conditions it is necessary to correct the raw profile data for variations in collisional quenching and electron detection sensitivity as a function of flame position. Establishing absolute radical concentrations is discussed in terms of partial equilibrium considerations and detailed flame structure calculations.
The giant-dipole resonance and radiative pion capture in 12C

Abstract Radiative pion capture is calculated for transitions to odd-parity states of 12 B. The results agree with the experiment of Bistirlich et al . The nuclear wave functions were constructed by coupling an sd nucleon to low-energy states of the Cohen-Kurath model for 11 C. These wave functions were tested on muon capture and photoabsorption and were found to give results in remarkable agreement with experiment.
Chemical topology: tying up some loose ends.

A linear molecule containing three bipyridine ligands can be wrapped around a single metal-ion template to form an open-knot complex. The loose ends of the knot can be 'tied' together through esterification or olefin-metathesis reactions to form closed knots that do not unravel when the metal template is removed.
The Imagined and Wished for Imperium of Reason and Science Russell's Empiricism and Its Relation to His and Our Ethics and Politics

Etude de la relation entre la philosophie des sciences et la philosophie morale de B. Russell. Analysant les rapports entre theorie et pratique, l'A. compare la definition empirique de l'activisme politique de Russell a sa propre conception de l'empirisme liberal applique aux domaines epistemologique et metaphysique
Transformation of the perturbation equations for the analysis of magnetohydrodynamic couette flow stability

The eigenvalue problem of the MHD stability analysis for nondissipative Couette flow between coaxially rotating cylinders in the presence of a uniform axial magnetic field, is transformed to one for the modified Mathieu equation with complex parameter and variable.
Tectonic significance of precambrian apatite fission-track ages from the midcontinent United States

Abstract Apparent apatite fission-track ages from drill core penetrating basement on the flank of the Transcontinental Arch in northwestern Iowa range from 934 ± 86 to 641 ± 90 Ma. These ages, the oldest reported in North America, record at least two thermal events. The 934 Ma age, which is synchronous with K-Ar ages in the Grenville Province and many K-Ar whole-rock and Rb-Sr isochron ages from the Lake Superior region, may document basement cooling caused by regional uplift and erosion of the crust. The remaining fission-track ages are products of a more recent thermal event, relative to the age of the samples, which raised temperatures into the zone of partial annealing. Heating may have occurred between the Middle Ordovician and Middle Cretaceous by burial of the basement with additional sediment. It is estimated that burial raised temperatures in the part of the basement sampled by the core to between 50 and 75°C. These temperature estimates imply paleogeothermal gradients of about 20°C/km, approximately two and one-half times present-day values, and burial of the basement by an additional 2–3 km of sediment.
Dear Diary: Logs in Group Counseling.

Logs written by group members after a session can be a powerful tool in group counseling. This article explores the uses of logs and suggests how they can further the success of group counseling in all settings. If used properly they heighten the awareness of personal and group dynamics and smooth the flow of communication.
Phase Behavior of Mixtures Containing Antibiotics. Chloramphenicol Partitioning

Phase equilibrium behavior of antibiotics is important in drug design and for optimization of the recovery processes in manufacturing. Antibiotics are high-cost fine chemicals, mostly manufactured by fermentation using inexpensive substrates. The major cost of manufacturing is involved in the separation processes. The aqueous/organic partitioning behavior of a clinically important antibiotic, chloramphenicol, is measured. The organic phase includes the pure solvents n-hexane, chloroform, diethyl ether, and ethyl acetate. In addition, measurements are also made for a mixed organic phase composed of n-hexane + ethyl acetate. Partitioning increases with the hydrogen bonding tendency of the solvent in the order n-hexane < chloroform < diethyl ether < ethyl acetate. Based on UNIQUAC and lattice-fluid hydrogen-bonding theories, an activity coefficient model (UNIQUAC-HB) is developed that includes hydrogen-bonding interaction. Single-solvent organic-phase data are correlated with the model, and free energy of hydrogen bonding parameters are obtained. Predictions made for mixed-solvent organic-phase systems agree well with the experimental data without using any adjustable parameter.
On the nature of persistent stratospheric clouds in the Antarctic

Thin, persistent very high clouds called “Stratospheric Cist” were reported at Maudheim base (71°03′S, 10°56′W) during the 1950–51 austral winters. The nature of these clouds, whether they are H 2 O or dust, is of importance in the proposed sink for stratospheric moisture in the Antarctic winter. Results are presented from analyses of unpublished daily cloud reports and daily upper air measurements from the Maudheim expedition. The results reveal strong evidence that the “Stratospheric Cist” were stratospheric ice clouds. Given this identification, an upper limit of 6–7 ppm can be assigned to the water vapor mixing ratio in the lower stratosphere for the 1950–51 Antarctic winters. DOI: 10.1111/j.2153-3490.1977.tb00765.x
Induced staggered field effects in antiferromagnets

Externally applied magnetic, electric and strain fields can, under certain conditions, induce staggered fields which couple to the order parameter of many antiferromagnets. Different physical effects and their microscopic origins are briefly reviewed and the importance of possible competitions is emphasized.
Carbon−Carbon Rotational Barriers in Butane, 1-Butene, and 1,3-Butadiene

The rotational barriers for n-butane, 1-butene, and 1,3-butadiene were calculated at the G2 and CBS-Q theoretical levels. The thermodynamic functions were obtained with explicit calculation of the effect of the rotational modes. The G2 difference in energy between the syn and anti forms of butane at 298 K is 5.1 kcal/mol, which is significantly larger than the experimental estimate. However, it is shown that a reliable experimental estimate of the barrier cannot be made based on the currently available data. The structural changes on rotation are examined and are related to the changes found for C−C bond rotation in ethane. The G2 model reproduces the observed relative energies for both 1-butene and 1,3-butadiene within the experimental uncertainties, and the CBS-Q model also gives generally satisfactory results.
Perturbation growth by thermal blooming in turbulence

The stability of a phase-compensated laser beam propagating in a turbulent absorbing fluid is considered. Small-scale transverse optical perturbations caused by turbulence and noise grow in thermal blooming by two instabilities: the uncompensated stimulated thermal Rayleigh scattering instability and the closed-loop instability. Linearized perturbation theory is used to calculate the electric field spectrum as a Taylor series in time and as a superposition of stable and unstable modes. The method is applicable to fluids with arbitrary parameter variations along the path. Compensated perturbations grow exponentially, and uncompensated ones grow quasi-exponentially. The instability growth rates and the turbulence and noise excitation strengths are derived for a simple fluid with homogeneous parameters. The linearized theory of perturbation growth is in good agreement with numerical simulations of full nonlinear thermal blooming. If the growth rate exceeds the damping rate from other phenomena, then the perturbations grow until they are limited by nonlinear saturation, at which point the beam is significantly degraded. At saturation the laser beam spontaneously breaks into small-scale transverse structures such as filaments or ribbons. The strongest damping mechanism in the open air is typically wind shear, which sets a threshold blooming rate and a threshold absorbed irradiance. Below threshold the perturbations grow linearly; above threshold they grow quasi-exponentially. Other atmospheric damping phenomena, such as diffusion and turbulent mixing, have a smaller effect.
Sparsity-Exploiting Robust Multidimensional Scaling

Multidimensional scaling (MDS) seeks an embedding of N objects in a p <; N dimensional space such that inter-vector distances approximate pairwise object dissimilarities. Despite their popularity, MDS algorithms are sensitive to outliers, yielding grossly erroneous embeddings even if few outliers contaminate the available dissimilarities. This work introduces robust MDS approaches exploiting the degree of sparsity in the outliers present. Links with compressive sampling lead to robust MDS solvers capable of coping with unstructured and structured outliers. The novel algorithms rely on a majorization-minimization approach to minimize a regularized stress function, whereby iterative MDS solvers involving Lasso and sparse group-Lasso operators are obtained. The resulting schemes identify outliers and obtain the desired embedding at computational cost comparable to that of their nonrobust MDS alternatives. The robust structured MDS algorithm considers outliers introduced by a sparse set of objects. In this case, two types of sparsity are exploited: i) sparsity of outliers in the dissimilarities; and ii) sparsity of the objects introducing outliers. Numerical tests on synthetic and real datasets illustrate the merits of the proposed algorithms.
Getting the Message Out to Older Adults: Effective HIV Health Education Risk Reduction Publications

Printed publications on HIV/AIDS for an older adult population were obtained from state public health departments within the United States in a previous study that explored the availability of age-...
Investigating a tribological failure

Abstract Investigation of a tribological failure is best carried out by following a series of steps, beginning with the obtaining of data on the failed mechanism, and inspection of the failed surfaces; then the computation of tribologically significant parameters, including wear volume, wear particle size and frictional heating. This is followed by the consultation of reference books and the carrying out of laboratory studies to test preliminary conclusions. It is hoped that a comprehensive explanation of what went wrong emerges, and this will suggest tests which will critically evaluate the explanation, and suggest ways of avoiding future failures.
The stress-strain behavior of the corneoscleral envelope of the eye II. In vivo measurements in rhesus monkey eyes

Abstract Optical interferometry was used to study the stress-strain relationships of the rhesus monkey eye in vivo and post mortem. The immediate strain pattern of the globe, both alive and dead, followed Friedenwald's ocular rigidity model rather well. The ocular rigidity coefficient of the living eye was found to be 0·026±0·001 μl −1 . A larger infusion volume was required to raise the pressure in the living eye as compared to the dead eye, a difference which was interpreted as being due to blood volume change in the living eye and which seemed to follow a log-linear relation with changes in vascular perfusion pressure. At higher intraocular pressures, these presumed blood volume changes were as large as the elastic volume strain of the globe. A viscoelastic strain pattern of the globe was observed during four minute simulated tonography. The time-dependent expansion appeared to be one-half the amplitude of the instantaneous expansion with a half-expansion time of approximately 1 min.
[Adjuvant chemotherapy in breast cancer--is omission an error?].

Adjuvant Chemotherapy in Breast Cancer – Is Omission an Error? Adjuvant chemotherapy in women with breast cancer is currently regarded as standard procedure. An efficacy of 10–20% can only be viewed as modest, even if a statistically significant prolonging of disease-free interval and overall survival has been established. The value of this mode of therapy is questionable because 80–90% of patients are subjected to chemotherapy with no effect, i.e. they would either have remained well regardless, or they are primarily resistant. In both cases, they are prone to suffering significant side effects. The cost-benefit ratio also needs to be taken into consideration. It is therefore recommended that the therapeutic effect is depicted in absolute percentages and not in relative percentages and absolute numbers. Only rendering the results as absolute percentages allows a true comparison between the small number of patients who benefit and the vast majority who do not. Even if this mode of therapy is regularly implemented worldwide by doctors, requested by patients and understandably backed by industry, the central question remains: ‘How great do the benefits of a particular therapy have to be, in order to justify its use? Who should set the limits?’ For the time being it therefore does not appear to be a mistake not to subject the patients in question to chemotherapy, unless they are part of a study.
Reply to comment on “A possible definition of basis set superposition error”

Abstract Contrary to the statements of Gutowski et al., the difference between the true dissociation energy and the counterpoise-corrected calculation of the dissociation energy is shown to be entirely a non-additive correction for basis set incompleteness.
B-cell conjunctival lymphoma in a cat

A bilateral conjunctival neoplasm was surgically removed from a 13-year-old Domestic Short-haired female cat and examined by histopathology. The neoplasm was infiltrative, nonencapsulated and composed of large sheets of densely packed, round to polygonal cells. Neoplastic cells were variably sized with scant to modest amounts of cytoplasm and oval to round nuclei. On immunohistochemistry the neoplastic cells stained positively for BLA.36 and negative for CD-3 antibodies. On the basis of histopathology and immunohistochemical findings, a diagnosis of conjunctival B-cell lymphoma was made. This is the first case with immunohistochemical characterization of conjunctival lymphoma in a cat.
Potential and structure controlled interfacial behavior of uracil derivatives.

Abstract The adsorption and related interfacial behavior of utacil, various methylated uracil derivatives, undine, uridine-5'-monophosphate and utidine-3'5'-cyclic monophosphate has been studied by surface electrochemical measurements at a mercury electrode. All uracil derivatives exhibit an initial “dilute” adsorption region where the virtually flat uracil residue is adsorbed flat on the electrode surface. In the case of uracil and its methylated derivatives the area occupied by one molecule is about 60–70 A 2 . Uracil, thymine and 1,5-dimethyluracil exhibit a second adsoiption region where they rearrange on the surface and adopt a perpendicular orientation and occupy about 40 A 2 per molecule. In this perpendicular orientation the uracils are bound to the electrode through the N(3)-H or perhaps N(1)-H functions in a manner similar to their Watson-Crick bonding in nucleic acids. When in the perpendicular orientation the adsorbed molecules undergo extensive stacking (association) interactions, again similar to those observed between adjacent bases in nucleic acids. The ability of a uracil derivative to undergo a surface reorientation is critically dependent on electrode potential, bulk-solution concentration and molecular structure.
Morphology of protein particles produced by spray freezing of concentrated solutions

The mechanisms for the formation of high surface area lysozyme particles in spray freezing processes are described as a function of spray geometry and atomization, solute concentration and the calculated cooling rate. In the spray freeze-drying (SFD) process, droplets are atomized into a gas and then freeze upon contact with a liquid cryogen. In the spray freezing into liquid (SFL) process, a solution is sprayed directly into the liquid cryogen below the gas-liquid meniscus. A wide range of feed concentrations is examined for two cryogens, liquid nitrogen (LN2) and isopentane (i-C5). The particle morphologies are characterized by SEM micrographs and BET measurements of specific surface area. As a result of boiling of the cryogen (Leidenfrost effect), the cooling rate for SFL into LN2 is several orders of magnitude slower than for SFL into i-C5 and for SFD in the case of either LN2 or i-C5. For 50 mg/mL concentrated feed solutions, the slower cooling of SFL into LN2 leads to a surface area of 34 m(2)/g. For the other three cases with more rapid cooling rates, surface areas were greater than 100 m(2)/g. The ability to adjust the cooling rate to vary the final particle surface area is beneficial for designing particles for controlled release applications.
Evaluation of micromilled metal mold masters for the replication of microchip electrophoresis devices

High-precision micromilling was assessed as a tool for the rapid fabrication of mold masters for replicating microchip devices in thermoplastics. As an example, microchip electrophoresis devices were hot embossed in poly(methylmethacrylate) (PMMA) from brass masters fabricated via micromilling. Specifically, sidewall roughness and milling topology limitations were investigated. Numerical simulations were performed to determine the effects of additional volumes present on injection plugs (i.e., shape, size, concentration profiles) due to curvature of the corners produced by micromilling. Elongation of the plug was not dramatic (< 20%) for injection crosses with radii of curvatures to channel width ratios less than 0.5. Use of stronger pinching potentials, as compared to sharp-corner injectors, were necessary in order to obtain short sample plugs. The sidewalls of the polymer microstructures were characterized by a maximum average roughness of 115 nm and mean peak height of 290 nm. Sidewall roughness had insignificant effects on the bulk EOF as it was statistically the same for PMMA microchannels with different aspect ratios compared to LiGA-prepared devices with a value of ca. 3.7 × 10−4 cm2/(V s). PMMA microchip electrophoresis devices were used for the separation of pUC19 Sau3AI double-stranded DNA. The plate numbers achieved in the micromilled-based chips exceeded 1 million/m and were comparable to the plate numbers obtained for the LiGA-prepared devices of similar geometry.
Direct emissivity measurements of IR materials

Emissivity measurements of ZnS, Sapphire, ALON, MgO, and Yttria were performed in 3.9-4.0 micrometers and 4.4-4.9 micrometers bands, for temperatures between 300 degrees C and 600 degrees C. The average radiance was measured over each waveband. Emissivity was calculated as the ratio of the radiance of the sample to that of a black body source at the same temperature. The results of the emissivity measurements for the above-mentioned materials will be reported. Measurement techniques that allowed increasing the dynamic range of the measurement and significantly reducing the noise will be discussed.
Unrestrained early age shrinkage of concrete with polypropylene, PVA, and carbon fibers

Plastic shrinkage cracking due to restrained shrinkage is a primary problem that often occurs in concrete structures with a relatively large surface area, such as concrete walls, bridge decks, slabs, and overlays. These applications are susceptible to rapid changes in temperature and humidity resulting in high water evaporation and high potential for shrinkage cracking. Free shrinkage at early age is one of the most influential factors leading to tensile stresses in concrete structures. When the tensile stress is higher than the tensile strength, cracking occurs. The addition of micro-fibers in amounts as small as 0.1% by volume is an effective method to control plastic shrinkage cracking. However, the effect of fibers on the free shrinkage and water evaporation of concrete is not clearly understood. The main objective of the study described in this paper is to evaluate the influence of fibers on the free shrinkage and water evaporation of fiber reinforced cement composites during the first 24,h after mixing, with particular attention to fiber content, fiber bond, and fiber stiffness. Prismatic concrete specimens of 1000,mm in length and 100 × 60,mm in cross section were tested to measure their unrestrained shrinkage strain. Simultaneously, flat concrete specimens of dimensions 327 × 230 × 50,mm were tested to determine loss of water by evaporation. The tests were carried out under adverse environmental conditions known to encourage high shrinkage, namely high temperature, low relative humidity, and exposure to high volume and velocity of air flow. Three types of fibers, polypropylene, PVA, and carbon fibers were investigated at four different fiber volume fractions, namely: 0.1%, 0.2%, 0.3%, and 0.4%. Experimental results are presented and conclusions are drawn.
Interactions of Blackbody Radiation with Atoms

Blackbody radiation affects low-frequency (${h}_{\ensuremath{\nu}}\ensuremath{\ll}\mathrm{kT}$) atomic transitions both by inducing transitions and producing ac frequency shifts, important effects that have previously been ignored. Here we report the calculation and experimental observation of a manifestation of the former, the threefold reduction of the Na $\mathrm{np}$ radiative lifetimes by 300-K blackbody-radiation-induced stimulated emission and absorption. Estimates of ac frequency shifts for Rydberg and ground-state atoms are given.
Nonparametric estimation with recurrent competing risks data.

Nonparametric estimators of component and system life distributions are developed and presented for situations where recurrent competing risks data from series systems are available. The use of recurrences of components’ failures leads to improved efficiencies in statistical inference, thereby leading to resource-efficient experimental or study designs or improved inferences about the distributions governing the event times. Finite and asymptotic properties of the estimators are obtained through simulation studies and analytically. The detrimental impact of parametric model misspecification is also vividly demonstrated, lending credence to the virtue of adopting nonparametric or semiparametric models, especially in biomedical settings. The estimators are illustrated by applying them to a data set pertaining to car repairs for vehicles that were under warranty.
Determining the Transrepression Activity of Xenoestrogen on Nuclear Factor-κB in Cos-1 Cells by Estrogen Receptor-α

Functional assays have been used to define the estrogenicity of xenoestrogens in cotransfection studies employing estrogen receptors in various cell lines. It is known that estrogen is able to affe...
Regional cerebral blood flow in mood disorders, V.: Effects of antidepressant medication in late-life depression.

Twenty elderly outpatients with major depression were treated with either nortriptyline or sertraline. Resting regional cerebral blood flow (rCBF) was assessed by the planar 133 Xenon inhalation technique after a medication washout and following 6– 9 weeks of antidepressant treatment. At baseline, the depressed sample had reduced rCBF in frontal cortical regions when compared with 20 matched normal-control subjects. After treatment, Responders and Nonresponders differed in the expression of a specific topographic alteration, with Responders manifesting reduced perfusion in frontal regions. These findings are consistent with this group's previous report of reduced rCBF after response to electroconvulsive therapy (ECT) and suggest a common mechanism of action.
A simplified assay for phosphoenolpyruvate.

Abstract A new method for analysis of phosphoenolpyruvate has been developed. The assay is based upon the stoichiometric conversion of ADP to ATP by the enzyme pyruvate kinase in the presence of variable amounts of PEP, and subsequent measurement of the ATP with a luciferin-luciferase preparation.
Vertically Aligned Carbon Nanotube Arrays for Room Temperature Gas Sensors

Vertically aligned multiwalled carbon nanotube (CNT) arrays were fabricated in anodized aluminum oxide (AAO) templates without the use of a catalyst, using xylene pyrolysis. The CNT arrays in AAO template were integrated into a resistive sensor design. The sensors were found to be highly responsive to NH3 and NO2 with steady state sensitivities of 5% and 10% for 100ppm of NH3 and NO2 respectively, at room temperature. Results were interpreted in terms of the CNTs acting as p-type semiconductors. A study was undertaken to elucidate the dependence of sensitivity on the thickness of the conducting amorphous carbon layers on top and bottom. Recovery of the MWNT gas sensor was studied for different types of desorption techniques. The thickness of the amorphous carbon layer (sheet resistance) was found to be critical in determining the sensor response.
Does Scientific Discovery Have a Logic

It is unusual for an author, less than one-tenth of the way through his work, to disclaim the existence of the subject matter that the title of his treatise announces. Yet that is exactly what Karl Popper does in his classic, The Logic of Scientific Discovery, [4], announcing in no uncertain terms on p. 31 that scientific discovery has no logic. The disclaimer is so remarkable that it deserves to be quoted at length: I said above that the work of the scientist consists in putting forward and testing theories.
A Hybrid Biomimetic Genetic Algorithm Using a Local Fuzzy Simplex Search

This paper presents a hybrid genetic algorithm that expands upon the previously successful approach of twinkling genetic algorithm (TGA) by incorporating a highly efficient local fuzzy-simplex search within the algorithm. The TGA was in principle a bio-mimetic algorithm that introduced a controlled deviation from a typical GA method, by not requiring that every genevariable of an offspring be the result of a crossover. Instead, twinkling allowed the genetic information of the randomly chosen gene locations to be directly passed on from one parent, which was shown to increase the likelihood of survival of a successful gene value within the offspring, rather than requiring it to be blended. The twinkling genetic algorithms proved highly effective at locating exact global optimum with a competitive rate of convergence for a wide variety of benchmark problems. In this work, it is proposed to couple the TGA with a fuzzy simplex local search to increase the rate of convergence of the algorithm. The proposed algorithm is tested using common mathematical and engineering design benchmark problems. Comparison of the results of this algorithm with earlier algorithms is presented.Copyright © 2010 by ASME
Palynological assessment of organic tissues and metallic minerals in the Jerritt Canyon gold deposit, Nevada (U.S.A.)

Abstract Organic tissues and metallic minerals were studied in acid residues and thin section of the Jerritt Canyon (Bell Mine) gold deposit. The purpose was to compare gold-bearing and gold-free rocks, characterize their differences, and assess a possible relationship between the invisible gold and the organic tissues in these early Paleozoic, carbonaceous limestones, dolomites, and claystones. The most visually abundant acid-resistant component in the sooty, unoxidized, gold-bearing rocks is a black, rectangular, carbon-bearing mineraloid. In X-ray diffraction, it is poorly crystalline; in nuclear magnetic resonance, it is a highly aromatized structure. The increase in gold content that accompanies the increase in content of this protographite suggests that it may be the major gold-bearing compound. Less abundant among the acid-resistant residues are uncarbonized organic tissues that are typical of marine settings. The tissues not in the vicinity of silicified veins are medium to dark brown. The dominant tissues are the amorphous remains of algae and their zooplankton predators. These uncarbonized indigenous tissues indicate that temperatures were lower than those determined by geochemical and fluid inclusion methods. The presence of different kinds of carbon-bearing compounds could account for the discrepancy between the palynological and geochemical data. The uncarbonized organic tissues comprise such a small percentage of these rocks that they could be easily missed by bulk analytical methods. The presence of uncarbonized tissues helps to constrain the duration of the high heat flow that is shown by the fluid inclusion data. The presence of mixed signals suggests that the protographite may be the product of chemical rather than thermal reactions.
HIF-1 mediates the Warburg effect in clear cell renal carcinoma.

Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that functions as a master regulator of oxygen homeostasis in all metazoan species. O2-dependent hydroxylation of two proline residues in the HIF-1α subunit is necessary for the binding of the von Hippel–Lindau (VHL) protein, which is a component of a ubiquitin protein ligase that ubiquitinates HIF-1α, leading to its degradation by the proteasome. In the majority of cases of the clear cell type of renal carcinoma, both VHL genes are inactivated by mutation or epigenetic silencing, leading to dysregulated HIF-1 transcriptional activity. VHL loss-of-function leads, under aerobic conditions, to a HIF-1-dependent reprogramming of glucose and energy metabolism that includes increased glucose uptake, glycolysis, and lactate production accompanied by a reciprocal decrease in respiration. These findings delineate for the first time the molecular mechanisms underlying the Warburg effect in a human cancer.
Rare gas diffusion in alkali metal iodides

Xenon-133 diffusion coefficients were measured in single crystals of KI, RbI, and CsI over the temperature range of 150 to 500 °C. Xenon was incorporated in the crystals both by doping with precursor I133 and by fission recoil from an external fissionable source. Consistent diffusion results were obtained which yielded single values for the diffusion activation energy over the temperature range of measurement. A gas concentration effect which was attributed to gas atom clustering was observed at concentrations as low as 10−9 gas atom fraction. Diffusion results were found to be most consistent with a model in which gas atoms associate with mobile defect clusters and diffuse with the clusters through the crystal lattice. Die Diffusionskoeffizienten von Xenon-133 wurden in KJ-, RbJ- und CsJ-Einkristallen im Temperaturaturbereich von 150 bis 500 °C gemessen. Xenon wurde sowohl durch Dotierung mit Tracer J133 als auch durch Spaltungsruckstos von einer auseren Kernquelle eingebaut. Konsistente Diffusionsergebnisse wurden erhalten und ergaben Einzelwerte fur die Aktivierungsenergie der Diffusion uber den Temperaturbereich der Messung. Ein Konzentrationseffekt des Gases wurde bei Konzentrationen bis herab zu 10−9 Gasatomanteilen beobachtet, der der Clusterbildung von Gasatomen zugeschrieben wird. Es wurde gefunden, das die Diffusionsergebnisse am besten einem Modell entsprechen, in dem Gasatome mit beweglichen Defektclustern assoziieren und mit den Clustern durch das Kristallgitter Diffundieren.
TEMPERATURE DEPENDENCE OF THE HYPERFINE COUPLING OF (Gd155) 3+ IN THORIUM OXIDE

Abstract The temperature dependence of the hyperfine constant of (Gd 155 ) 3+ was measured and is compared to existing theory.
Physiologic assessment of fetal compromise: biomarkers of toxic exposure.

Understanding the physiologic and endocrinologic basis of fetal development is a major goal of perinatal biology. During the past decade a number of technological developments have allowed more precise evaluation of the fetus in utero and diagnosis of abnormalities. Despite these methodological achievements, however, there are no specific biological markers currently available to indicate that exposure to a given xenobiotic is associated with a cellular, subcellular, or pharmacodynamic event. This paper evaluates the following issues: What are some of the unique physiologic and endocrinologic features of the fetal milieu interieur? What problems are peculiar to fetal assessment? Of what value are techniques such as ultrasonography, amniocentesis, chorionic villus sampling, fetoscopy, and fetal blood and tissue sampling for obtaining appropriate biomarkers? What are some examples of validated biomarkers and their applicability? What promising biomarkers are on the horizon? What are some of the promising techniques such as the evaluation of fetal body movements, breathing activity, electronic heart rate monitoring, and nuclear magnetic resonance? How may molecular probes be of value as biological markers of fetal compromise? What are some of the major research gaps and needs, and how should research priorities be set? Some of these topics are addressed. Moreover, the more general role(s) that various diagnostic methods and biological markers can have in an understanding of the regulation of fetal growth and differentiation and the role of xenobiotics in affecting the normal course of events are discussed.
Stereochemistry of the puromycin reaction

Summary Space-filling models have shown that peptidyl-puromycin cannot be formed if puromycin is displacing the end of aminoacyl-tRNA. Instead, the models show that puromycin “hugs” the terminus of peptidyl-tRNA in such a way that the free amino group of the antibiotic is in a perfect position for a nucleophylic attack on the carbonyl carbon of the peptide. In this configuration there is a continuous “stack” of four hydrophobic rings, with the dimethyladenine and methoxy-benzene of the antibiotic alternating with the terminal adenine and penultimate cytosine of peptidyl-tRNA. This is an essential feature because it helps to bind the tRNA after its adenine has been displaced from the peptidyl site. The model predicts the existence of a puromycin-binding protein in the ribosome.
More on the non-equivalence of voluntary export restraints

Abstract This note demonstrates that VERs limiting exporters to a percentage of the domestic market are not equivalent to other trade restrictions, and that they can be inferior to equivalent import quotas even when the quota rents accrue to foreign exporters.
Towards Tracking Moving Single Molecules in Atomic Force Microscopy

The atomic force microscope (AFM) is an invaluable tool for observing biological systems, due in part to its incomparable resolution as well as its ability to observe systems in their physiological environments and to measure mechanical properties directly. Its slow imaging rate, however, greatly reduces its applicability in recording fast-changing mechanisms. Such studies are of critical importance. For example, investigating the dynamics of protein motors and other macromolecules is essential for understanding and treating a variety of genetic diseases. Motivated by this, we are developing an approach to AFM centering on tracking rather than imaging. The scheme is primarily designed to follow the motion of a single macromolecule moving along a biopolymer. In approaching this problem, we consider that the presence of the moving macromolecule on its track results in a change in the apparent width of the track. Based on this, we have developed a high-speed width detector that rapidly determines the width by detecting the two edges of the sample during a fast scan. As a result, the motion of these single macromolecules is derived from direct tracking rather than a sequence of images. Such an approach promises a much higher temporal resolution than is achievable in time-lapse imaging.
THE CULTURAL ECOLOGY OF ECONOMIC DEVELOPMENT

The conventional approach to economic development assumes that if a surplus of land and labor exists in village systems, the introduction of commercial activities will not be detrimental to the subsistence system. A cultural-ecological perspective on economic development reveals a more complex process of change in human-environment relationships than the conventional approach. An analysis of the impact of the introduction of cattle raising and coffee production in the highlands of Papua New Guinea indicates that the relative location of activities, the linkages within the local ecosystem, the seasonality of labor inputs, the sociocultural context, and the patterns of cash expenditure must be considered in examining the potential integration of subsistence and cash earning. Cash earning can have a detrimental impact on subsistence systems, even when surplus land and labor exist. Loss of autonomy in relation to outside commercial networks reduces the resilience of village systems.
Analytic theory for the selection of a two-dimensional needle crystal at arbitrary Péclet number.

An accurate analytic theory is presented for the velocity selection of a two-dimensional needle crystal for arbitrary Peclet number for small values of the surface tension parameter. The velocity selection is caused by the effect of transcendentally small terms which are determined by analytic continuation to the complex plane and analysis of nonlinear equations. The work supports the general conclusion of previous small Peclet number analytical results of other investigators, though there are some discrepancies in details. It also addresses questions raised on the validity of selection theory owing to assumptions made on shape corrections at large distances from the tip.
ESAM: adding to the hematopoietic toolbox.

In this issue of Blood , Yokota and colleagues define ESAM as a novel marker that facilitates isolation of multipotential lympho-myeloid hematopoietic stem and progenitor cells in mice throughout ontogeny. Distinction of hematopoietic stem cells (HSCs) from differentiated cells is essential for
A new model for the erosion of metals at normal incidence

Abstract A new theoretical model is proposed for the erosion of metals by particles at normal incidence. The model employs a criterion of critical plastic strain to determine when the material will be removed. This critical plastic strain is defined as the strain at which the deformation in the target localizes and hence results in the lip formation. It is shown that, under typical erosion conditions, the “localization” model is more appropriate than the “fatigue” models. Finally, it is demonstrated that the new model predicts quite well all the essential features of the normal impact erosion process.
On the attenuation of direct solar irradiance in Athens due to aerosols

In this study the trend of the time sequence of the “integral aerosol optical depth” (ka), as proposed by Unsworth and Monteith, was determined for clear days in summer for the period 1962–1988 in Athens. The trend was found by fitting a third degree polynomial curve and it was concluded that (ka) showed a considerable increase (i.e. from the value of 0.18 to 0.31) in the period 1962–1976 and remained approximately constant until 1979, after which it started decreasing again slowly until 1988. The increase of (ka) in the period 1962–1976 is likely attributable to the rapid development of the city in this period, while the decrease of (ka) after 1979 probably reflects the efficiency of some restrictions which were imposed on the pollutant emissions during this period. In addition, an analysis of the percentage frequency distribution found that while 95% of the values of (ka) ranged from 0.100 to 0.400 in the beginning of the period (1964–1967), in recent years (1984–1987) the same percentage of the values of (ka) ranged from 0.100 to 0.500.
Plant protection by the activation of latent mechanisms for resistance

The interactions, green bean-Colletotrichum lindemuthianum and cucurbits-Colletotrichum lagenarium, have been used in our laboratory to study the presence and activation of latent mechanisms for disease resistance in plants. Green bean hypocotyls inoculated with cultivar-non-pathogenic races of C. lindemuthianum, the heat-attenuated fungus, or some non-pathogens of green bean were locally and systemically protected from disease caused by subsequent inoculations with cultivar-pathogenic races of the fungus. Cultivars of bean susceptible to all known races of the pathogen were protected against the pathogen by prior inoculation with some non-pathogens. Recently we observed that inoculation of a cotyledon or first true leaf of cucumber, watermelon or muskmelon with Colletotrichum lagenarium systemically protected plants against the pathogen. Protection was evident as a reduction in the number and size of lesions. Inoculation of the first true leaf, when the second true leaf was partially expanded, systemically protected cucumber plants for 4–5 weeks. Plants at this time had 8–12 leaves. A second or booster inoculation 3 weeks after the first inoculation extended protection, and protection was effective with resistant and susceptible cucumber cultivars. A direct relationship existed between the number of spores used for protection and the extent and duration of protection. A single lesion elicited significant protection. Inoculated leaf one was not necessary to maintain protection of leaf two or to initiate and maintain protection in developing leaves once protection was initiated in leaf two. Inoculation of leaf one with the pathogen protected cucumber and watermelon plants in the field against the pathogen. Results from our experiments support the contention that all plants have efficient mechanisms for disease resistance though resistance may be latent in the presence of some pathogens under certain conditions. Activation of mechanisms for resistance may provide a practical means for disease control by plant immunization and suggests a new approach to breeding for disease resistance in plants.