Estimation of soil hydraulic properties and their uncertainty: comparison between laboratory and field experiment

Often the soil hydraulic parameters are obtained by the inversion of measured data (e.g. soil moisture, pressure head, and cumulative infiltration, etc.). However, the inverse problem in unsaturated zone is ill-posed due to various reasons, and hence the parameters become non-unique. The presence of multiple soil layers brings the additional complexities in the inverse modelling. The generalized likelihood uncertainty estimate (GLUE) is a useful approach to estimate the parameters and their uncertainty when dealing with soil moisture dynamics which is a highly non-linear problem. Because the estimated parameters depend on the modelling scale, inverse modelling carried out on laboratory data and field data may provide independent estimates. The objective of this paper is to compare the parameters and their uncertainty estimated through experiments in the laboratory and in the field and to assess which of the soil hydraulic parameters are independent of the experiment. The first two layers in the field site are characterized by Loamy sand and Loamy. The mean soil moisture and pressure head at three depths are measured with an interval of half hour for a period of 1 week using the evaporation method for the laboratory experiment, whereas soil moisture at three different depths (60, 110, and 200 cm) is measured with an interval of 1 h for 2 years for the field experiment. A one-dimensional soil moisture model on the basis of the finite difference method was used. The calibration and validation are approximately for 1 year each. The model performance was found to be good with root mean square error (RMSE) varying from 2 to 4 cm(3) cm(-3). It is found from the two experiments that mean and uncertainty in the saturated soil moisture (theta(s)) and shape parameter (n) of van Genuchten equations are similar for both the soil types. Copyright (C) 2010 John Wiley & Sons, Ltd.

Non-contractible non-edges in 2-connected graphs

Any pair of non-adjacent vertices forms a non-edge in a graph. Contraction of a non-edge merges two non-adjacent vertices into a single vertex such that the edges incident on the non-adjacent vertices are now incident on the merged vertex. In this paper, we consider simple connected graphs, hence parallel edges are removed after contraction. The minimum number of nodes whose removal disconnects the graph is the connectivity of the graph. We say a graph is k-connected, if its connectivity is k. A non-edge in a k-connected graph is contractible if its contraction does not result in a graph of lower connectivity. Otherwise the non-edge is non-contractible. We focus our study on non-contractible non-edges in 2-connected graphs. We show that cycles are the only 2-connected graphs in which every non-edge is non-contractible. (C) 2010 Elsevier B.V. All rights reserved.

Thermodynamic properties of strontium titanates Sr2TiO4, Sr3Ti2O7, Sr4Ti3O10, and SrTiO3

The chemical potentials of SrO in two-phase fields (TiO2 + SrTiO3) (SrTiO3 + Sr4Ti3O10) (Sr4Ti3O10 + Sr3Ti2O7) and (Sr3Ti2O7 + Sr2TiO4) of the pseudo-binary system (SrO + TiO2) have been measured in the temperature range (900 to 1250) K relative to pure SrO as the reference state using solid-state galvanic cells incorporating single crystal SrF2 as the electrolyte The cells were operated under pure oxygen at ambient pressure The standard Gibbs free energies of formation of strontium titanates SrTiO3 Sr4Ti3O10 Sr3Ti2O7 and Sr2TiO4 from their component binary oxides were derived from the reversible electromotive force (EMF) of the cells For the formation of the four compounds from their component oxides TiO2 with rutile structure and SrO the standard Gibbs free energy changes are given by Delta G((ox))(SrTiO3) +/- 89/(J mol(-1)) = -121878 + 3 881(T/K) Delta G((ox))(Sr4Ti3O10) +/- 284/(J mol(-1)) = -409197 + 14 749(T/K) Delta G((ox))(Sr3Ti2O7) +/- 190/(J mol(-1)) = -285827 + 10 022(T/K) Delta G((ox))(Sr2TiO4) +/- 110/(J mol(-1))= -159385 + 3 770(T/K) The reference state for solid TiO2 is the rutile form The results of this study are in good agreement with Gibbs free energy of formation data reported in the literature for SrTiO3 but differ significantly with data for Sr4Ti3O10 For Si3Ti2O7 and Si2TiO4 experimental measurements are not available in the literature for direct comparison with the results obtained in this study (C) 2010 Elsevier Ltd All rights reserved

An Investigation Of Alkali Aluminosilicate Glasses By Si-29 And Al-27 Magic-Angle-Spinning Nmr-Spectroscopy

Alkali aluminosilicate glasses prepared by the gel and the melt routes have been investigated by Si-29 and Al-27 MAS NMR spectroscopy. It is found that Al has a tetrahedral coordination in the gel glasses modified with equivalent proportions of alkalis unlike in a pure aluminosilicate glass where Al has both four and six coordinations. Silicon is present as Q4 units in all the 5M2O 5Al2O3 9OSiO2 ( M = Li, Na and K) gel glasses studied whereas it is present in Q2 or Q3 species in the lithium aluminosilicate glasses of compositions 40Li2O x Al2O3 (1-x)SiO2 (1 less-than-or-equal-to x less-than-or-equal-to 15) and xLi2O 10Al2O3 (1-x)SiO2 (20 less-than-or-equal-to x less-than-or-equal-to 40). The combination of Q2 and Q3 is also found in certain sodium aluminosilicate glasses, but they change to Q2 and Q1 as the concentration of SiO2 decreases.

Energy for the Developing World

Described are methods which can be used by developing countries to affordably obtain the energy without ruining the environment. The approaches mix efficient end-use technologies with modest increases in generating capacity. (CW).

Detection of a CpA methylase in an insect system: characterization and substrate specificity

A cytosine-specific DNA methyltransferase (EC 2.1.1.37) has been purified to near homogeneity from a mealybug (Planococcus lilacinus). The enzyme can methylate cytosine residues in CpG sequences as well as CpA sequences. The apparent molecular weight of the enzyme was estimated as 135,000 daltons by FPLC. The enzyme exhibits a processive mode of action and a salt dependance similar to mammalian methylases. Mealybug methylase exhibits a preference for denatured DNA substrates.

Dislocation characterization in crystals of potash alum grown by seeded solution growth under conditions of low supersaturation

An analysis has been carried out of the genesis and character of growth dislocations present in all growth sectors of single crystals of potash alum. The crystals, grown from seeded solutions by the temperature lowering method under conditions of low supersaturation, presented the well-developed forms: {111} dominant, {100} and {110}. Growth dislocations formed predominately during refacetting of the edges and corners of the seed, rounded during preparation and insertion into the supersaturated solution. From here they become refracted into the {111} sectors which proved to be the most defective. Smaller numbers of dislocations form at the {111}, {100} and {110} seed interfaces and propagate in these sectors. In crystals of inferior quality, a number of inclusions were found predominantly in the fast growing {100} sectors which become the source of additional dislocations. Dislocations present in the original seed did not propagate across the interface into the developing crystal. Dislocations of all characters were observed. The principal Burgers vectors were found to be left angle bracket100right-pointing angle bracket, left angle bracket110right-pointing angle bracket and left angle bracket111right-pointing angle bracket.

Architecture of Physalis Mottle Tymovirus as Probed by Monoclonal Antibodies and Cross-Linking Studies

Physalis mottle tymovirus (previously named belladonna mottle virus, Iowa strain) RNA was cross-linked to its coat protein by exposure of the intact virus to ultraviolet light. The site of cross-linking of the coat protein with the RNA was identified as Lys-10 by sequencing the oligonucleotide-linked tryptic peptide obtained upon HPLC separation subsequent to enzymetic digestion of the cross-linked and dissociated virus. Three monoclonal antibodies PA3B2, PB5G9, and PF12C9, obtained using denatured coat protein as antigen, cross-reacted effectively with the intact virus indicating that the epitopes recognized by these monoclonals are on the surface of the virus. Using the peptides generated by digestion with CNBr, clostripain, V-8 protease, or trypsin and a recombinant protein lacking the N-terminal 21 residues expressed from a cDNA clone, it was shown that PA3B2 recognizes the sequence 22-36 on the coat protein while PB5G9 and PF12C9 recognize region 75-110. These results suggest that Lys-10 is one of the specific sites through which the RNA interacts in the intact virus. The polypeptide segment (region 22-36) following this buried portion as well as the epitope within the region 75-110 are exposed in the intact virus. These observations are consistent with the canonical β-barrel structure observed in certain other plant viruses.

Pakkausmerkinnän vaikutus kuluttajan ostokäyttäytymiseen elintarvikekriisissä – tapaustutkimus Lisäaineeton-pakkausmerkinnästä valmisruoassa

Tutkimuksen tavoitteena oli tarkastella pakkausmerkinnän vaikutusta kuluttajan ostokäyttäytymiseen lisäaineita käsittelevässä elintarvikekriisissä Tutkittavia osa-alueita olivat ostoaikomus, asenteet, luottamus, informaatio ja havaittu riski. Lisäksi tutkimuksella pyrittiin selvittämään, kuinka tärkeä ominaisuus lisäaineettomuus on ruoan valinnassa ja kuinka kiinnostuneita vastaajat ovat lisäaineettomuudesta kertovista pakkausmerkinnöistä. Tutkimus rajattiin koskemaan valmisruokaa, koska sen mielletään tutkimusten mukaan sisältävän paljon lisäaineita. Tutkimuksen teoriaosuus muodostui lisäaineita, elintarvikekriisejä, kuluttajan ostokäyttäytymistä ja pakkausmerkintöjä käsittelevästä kirjallisuudesta. Keskeisenä kuluttajakäyttäytymisen teoriana tutkimuksessa oli Izek Ajzenin luoma ”Theory of planned behaviour” eli ns. suunnitellun käyttäytymisen malli. Kuluttajan käyttäytymistä kriisitilanteesta mallinnettiin ns. SPARTA-teorian avulla, jossa luottamus ja havaittu riski on erotettu omiksi käyttäytymiseen vaikuttaviksi muuttujikseen. Teorian loppuosio käsitteli pakkausmerkintöjä ja niiden tehtäviä tuotteessa. Kirjallisuuden perusteella teoriaosion lopuksi tunnistettiin ne pakkausmerkintöjen tavoitteet, joita niille asetettiin kriisitilanteessa. Tutkimuksessa hyödynnettiin kahta tutkimusmenetelmää: kokeellista ja survey-tutkimusta. Kokeellisessa osiossa pyrittiin tutkimaan, onko pakkausmerkinnällä tilastollisesti merkitsevää vaikutusta kriisikäyttäytymisen osa-alueisiin. Tutkimuksen kuvaileva osio suoritettiin survey-menetelmän avulla. Aineisto kerättiin informoidun kyselyn avulla pääkaupunkiseudun ostoskeskuksissa syksyllä 2011. Aineisto koostuu 110 vastaajan tiedoista, jotka olivat 15–79 -vuotiaita. Aineiston analyysissä käytettiin useita tilastollisia menetelmiä, kuten Spearmanin järjestyskorrelaatiokerrointa, ristiintaulukointia ja ?2 -riippumattomuustestiä ja Wilcoxonin mediaanitestiä. Lisäaineettomuus oli tärkeä ominaisuus ruoan valinnassa 66 % vastaajista. Lisäaineettomuus oli tärkeä valintaperuste erityisesti naisille, iäkkäämmille vastaajille ja heille, jotka liittivät lisäaineisiin suuremman riskin. Vastaajista 76 % oli kiinnostunut näkemään lisää lisäaineettomuudesta kertovia pakkausmerkintöjä. Naiset olivat merkinnöistä miehiä kiinnostuneempia. Lisäaineeton-pakkausmerkinnällä oli tilastollisesti merkitsevää vaikutusta kuluttajan ostoaikomukseen, asenteisiin ja luottamukseen. Merkinnät lisäsivät ostoaikomusta ja luottamusta. Suurin vaikutus merkinnöillä oli asenteisiin, jotka paranivat. Havaittuun riskiin tai informaatioon pakkausmerkinnällä ei ollut tilastollisesti merkitsevää vaikutusta.