Selecting Acid-Soil Tolerant White Clover

A two-stage, tandem, recurrent-selection program is proposed to improve acid-soil tolerance of white clover, Trifolium repens L. In stage one, we evaluate root growth of very young seedlings, grown in an highly-acid Al toxic soil. Although the relationship between the acid-soil response of very young seedlings and that of mature white clover is unknown, the failure of white clover to become established on a highly-acid, Al-toxic soil suggests that establishment is a critical stage of plant development on such soils. In stage two we reevaluate genotypes selected in stage one, in a small-pot study at two lime levels, to separate the effects of plant vigor and acid-soil tolerance, account for any effects of growth stage on evaluation results and ensure that all genotypes selected are vigorous in soils with a higher pH

The FEM-2 design method

The FEM-2 parallel computer is designed using methods differing from those ordinarily employed in parallel computer design. The major distinguishing aspects are: (1) a top-down rather than bottom-up design process; (2) the design considers the entire system structure in terms of layers of virtual machines; and (3) each layer of virtual machine is defined formally during the design process. The result is a complete hardware/software system design. The basic design method is discussed and the advantages of the method are considered. A status report on the FEM-2 design is included

Ultrasonic studies of the magnetic phase transition in MnSi

Measurements of the sound velocities in a single crystal of MnSi were performed in the temperature range 4-150 K. Elastic constants, controlling propagation of longitudinal waves reveal significant softening at a temperature of about 29.6 K and small discontinuities at $\sim$28.8 K, which corresponds to the magnetic phase transition in MnSi. In contrast the shear elastic moduli do not show any softening at all, reacting only to the small volume deformation caused by the magneto-volume effect. The current ultrasonic study exposes an important fact that the magnetic phase transition in MnSi, occurring at 28.8 K, is just a minor feature of the global transformation marked by the rounded maxima or minima of heat capacity, thermal expansion coefficient, sound velocities and absorption, and the temperature derivative of resistivity.Comment: 4 pages, 4 figure

"Честный" и "нечестный" маркетинг: пример DeSheli

В статье рассматриваются критерии "честного" и "нечестного" маркетинга, выделены основные принципы маркетинга, описаны методы "недобросовестного" маркетинга, приводятся приемы "нечестного" маркетинга, используемые компанией DeSheli, приведены рекомендации, как не попасться на нечестных маркетологов, а также, если вы поддались провокациям и оформили кредит на косметику, но после того осознали, что совершили ошибку, несколько правил, как вернуть деньги

Arabidopsis SYT1 maintains stability of cortical endoplasmic reticulum networks and VAP27-1-enriched endoplasmic reticulum–plasma membrane contact sites

Arabidopsis synaptotagmin 1 (SYT1) is localized on the endoplasmic reticulum–plasma membrane (ER–PM) contact sites in leaf and root cells. The ER–PM localization of Arabidopsis SYT1 resembles that of the extended synaptotagmins (E-SYTs) in animal cells. In mammals, E-SYTs have been shown to regulate calcium signaling, lipid transfer, and endocytosis. Arabidopsis SYT1 was reported to be essential for maintaining cell integrity and virus movement. This study provides detailed insight into the subcellular localization of SYT1 and VAP27-1, another ER–PM-tethering protein. SYT1 and VAP27-1 were shown to be localized on distinct ER–PM contact sites. The VAP27-1-enriched ER–PM contact sites (V-EPCSs) were always in contact with the SYT1-enriched ER–PM contact sites (S-EPCSs). The V-EPCSs still existed in the leaf epidermal cells of the SYT1 null mutant; however, they were less stable than those in the wild type. The polygonal networks of cortical ER disassembled and the mobility of VAP27-1 protein on the ER–PM contact sites increased in leaf cells of the SYT1 null mutant. These results suggest that SYT1 is responsible for stabilizing the ER network and V-EPCSs

Experimental demonstration of fractional orbital angular momentum entanglement of two photons

The singular nature of a non-integer spiral phase plate allows easy manipulation of spatial degrees of freedom of photon states. Using two such devices, we have observed very high dimensional (D > 3700) spatial entanglement of twin photons generated by spontaneous parametric down-conversion.Comment: submitted to Phys. Rev. Let

Forage Production Potential of Poa Arachnifera Torr in Semi-Arid Climates

This study was undertaken to determine the forage potential of Texas bluegrass (Poa arachnifera Torr). Texas bluegrass is a perennial coolseason grass native to Kansas, Oklahoma, western Arkansas, and the central region of Texas, USA (Gould, 1975). Thirteen different accessions were established in 1988 at the Texas A&M University Centers at Dallas and Stephenville and tested for 2 years. Mean yields at Stephenville and Dallas were 3610 and 6022 kg ha-1. Two synthetic varieties (Syn-1 and Syn-2) were tested from 1990 to 1995 at four locations in Texas. Yields of Syn-1 was greater than Syn-2 whereas Syn- 2 provided significantly higher mortality than Syn-1 of larvae of the fall armyworm (Spodoptera frugiperda (J.E. Smith)) in nochoice laboratory feeding tests

Defoliation and patchy nutrient return drive grazing effects on plant and soil properties in a dairy cow pasture

Large herbivores can influence plant and soil properties in grassland ecosystems, but especially for belowground biota and processes, the mechanisms that explain these effects are not fully understood. Here, we examine the capability of three grazing mechanisms-plant defoliation, dung and urine return, and physical presence of animals (causing trampling and excreta return in patches)-to explain grazing effects in Phleum pratense-Festuca pratensis dairy cow pasture in Finland. Comparison of control plots and plots grazed by cows showed that grazing maintained original plant-community structure, decreased shoot mass and root N and P concentrations, increased shoot N and P concentrations, and had an inconsistent effect on root mass. Among soil fauna, grazing increased the abundance of fungivorous nematodes and Aporrectodea earthworms and decreased the abundance of detritivorous enchytraeids and Lumbricus earthworms. Grazing also increased soil density and pH but did not affect average soil inorganic-N concentration. To reveal the mechanisms behind these effects, we analyzed results from mowed plots and plots that were both mowed and treated with a dung and urine mixture. This comparison revealed that grazing effects on plant attributes were almost entirely explained by defoliation, with only one partly explained by excreta return. Among belowground attributes, however, the mechanisms were more mixed, with effects explained by defoliation, patchy excreta return, and cow trampling. Average soil inorganic-N concentration was not affected by grazing because it was simultaneously decreased by defoliation and increased by cow presence. Presence of cows created great spatial heterogeneity in soil N availability and abundance of fungivorous nematodes. A greenhouse trial revealed a grazing-induced soil feedback on plant growth, which was explained by patchiness in N availability rather than changes in soil biota. Our results show that grazing effects on plant attributes can be satisfactorily predicted using the effects of defoliation, whereas those on soil fauna and soil N availability need understanding of other mechanisms as well. The results indicate that defoliation-induced changes in plant ecophysiology and the great spatial variation in N availability created by grazers are the two key mechanisms through which large herbivores can control grassland ecosystems.Large herbivores can influence plant and soil properties in grassland ecosystems, but especially for belowground biota and processes, the mechanisms that explain these effects are not fully understood. Here, we examine the capability of three grazing mechanisms-plant defoliation, dung and urine return, and physical presence of animals (causing trampling and excreta return in patches)-to explain grazing effects in Phleum pratense-Festuca pratensis dairy cow pasture in Finland. Comparison of control plots and plots grazed by cows showed that grazing maintained original plant-community structure, decreased shoot mass and root N and P concentrations, increased shoot N and P concentrations, and had an inconsistent effect on root mass. Among soil fauna, grazing increased the abundance of fungivorous nematodes and Aporrectodea earthworms and decreased the abundance of detritivorous enchytraeids and Lumbricus earthworms. Grazing also increased soil density and pH but did not affect average soil inorganic-N concentration. To reveal the mechanisms behind these effects, we analyzed results from mowed plots and plots that were both mowed and treated with a dung and urine mixture. This comparison revealed that grazing effects on plant attributes were almost entirely explained by defoliation, with only one partly explained by excreta return. Among belowground attributes, however, the mechanisms were more mixed, with effects explained by defoliation, patchy excreta return, and cow trampling. Average soil inorganic-N concentration was not affected by grazing because it was simultaneously decreased by defoliation and increased by cow presence. Presence of cows created great spatial heterogeneity in soil N availability and abundance of fungivorous nematodes. A greenhouse trial revealed a grazing-induced soil feedback on plant growth, which was explained by patchiness in N availability rather than changes in soil biota. Our results show that grazing effects on plant attributes can be satisfactorily predicted using the effects of defoliation, whereas those on soil fauna and soil N availability need understanding of other mechanisms as well. The results indicate that defoliation-induced changes in plant ecophysiology and the great spatial variation in N availability created by grazers are the two key mechanisms through which large herbivores can control grassland ecosystems.Large herbivores can influence plant and soil properties in grassland ecosystems, but especially for belowground biota and processes, the mechanisms that explain these effects are not fully understood. Here, we examine the capability of three grazing mechanisms-plant defoliation, dung and urine return, and physical presence of animals (causing trampling and excreta return in patches)-to explain grazing effects in Phleum pratense-Festuca pratensis dairy cow pasture in Finland. Comparison of control plots and plots grazed by cows showed that grazing maintained original plant-community structure, decreased shoot mass and root N and P concentrations, increased shoot N and P concentrations, and had an inconsistent effect on root mass. Among soil fauna, grazing increased the abundance of fungivorous nematodes and Aporrectodea earthworms and decreased the abundance of detritivorous enchytraeids and Lumbricus earthworms. Grazing also increased soil density and pH but did not affect average soil inorganic-N concentration. To reveal the mechanisms behind these effects, we analyzed results from mowed plots and plots that were both mowed and treated with a dung and urine mixture. This comparison revealed that grazing effects on plant attributes were almost entirely explained by defoliation, with only one partly explained by excreta return. Among belowground attributes, however, the mechanisms were more mixed, with effects explained by defoliation, patchy excreta return, and cow trampling. Average soil inorganic-N concentration was not affected by grazing because it was simultaneously decreased by defoliation and increased by cow presence. Presence of cows created great spatial heterogeneity in soil N availability and abundance of fungivorous nematodes. A greenhouse trial revealed a grazing-induced soil feedback on plant growth, which was explained by patchiness in N availability rather than changes in soil biota. Our results show that grazing effects on plant attributes can be satisfactorily predicted using the effects of defoliation, whereas those on soil fauna and soil N availability need understanding of other mechanisms as well. The results indicate that defoliation-induced changes in plant ecophysiology and the great spatial variation in N availability created by grazers are the two key mechanisms through which large herbivores can control grassland ecosystems.Peer reviewe

Shear modulus of the hadron-quark mixed phase

Robust arguments predict that a hadron-quark mixed phase may exist in the cores of some "neutron" stars. Such a phase forms a crystalline lattice with a shear modulus higher than that of the crust due to the high density and charge separation, even allowing for the effects of charge screening. This may lead to strong continuous gravitational-wave emission from rapidly rotating neutron stars and gravitational-wave bursts associated with magnetar flares and pulsar glitches. We present the first detailed calculation of the shear modulus of the mixed phase. We describe the quark phase using the bag model plus first-order quantum chromodynamics corrections and the hadronic phase using relativistic mean-field models with parameters allowed by the most massive pulsar. Most of the calculation involves treating the "pasta phases" of the lattice via dimensional continuation, and we give a general method for computing dimensionally continued lattice sums including the Debye model of charge screening. We compute all the shear components of the elastic modulus tensor and angle average them to obtain the effective (scalar) shear modulus for the case where the mixed phase is a polycrystal. We include the contributions from changing the cell size, which are necessary for the stability of the lower-dimensional portions of the lattice. Stability also requires a minimum surface tension, generally tens of MeV/fm^2 depending on the equation of state. We find that the shear modulus can be a few times 10^33 erg/cm^3, two orders of magnitude higher than the first estimate, over a significant fraction of the maximum mass stable star for certain parameter choices.Comment: 22 pages, 12 figures, version accepted by Phys. Rev. D, with the corrections to the shear modulus computation and Table I given in the erratu

High pressure Ca-VI phase between 158-180 GPa: Stability, electronic structure and superconductivity

We have performed ab initio calculations for new high-pressure phase of Ca-VI between 158-180 GPa. The study includes elastic parameters of mono- and poly-crystalline aggregates, electronic band structure, lattice dynamics and superconductivity. The calculations show that the orthorhombic Pnma structure is mechanically and dynamically stable in the pressure range studied. The structure is superconducting in the entire pressure range and the calculated Tc (~25K) is maximum at ~172 GPa, where the transfer of charges from 4s to 3d may be thought to be completed.Comment: 8 pages, 4 figures; PACS number(s): 74.70.Ad, 62.20.de, 71.20.-b, 74.20.Pq, 74.25.Kc, 74.62.Fj; Keywords: Calcium; High pressure; Electronic band structure; Phonon spectrum; Elastic constants; Superconducto