Semi-quantitative Information Research Articles

STEREOLOGICAL ESTIMATION OF ITO CELLS FROM RAT LIVER USING THE OPTICAL FRACTIONATOR - A PRELIMINARY REPORT

In the last two decades, much light has been shed on hepatic fibrosis, and the activation / proliferation of Ito cells (IC) emerged to play a central role. Therefore, it is essential to have solid quantitative data in nonpathological statuses; yet, this data is scarce and confined to "number per area" or semiquantitative information. Moreover, the supposed heterogeneous distribution of IC in the hepatic lobule was never analysed with design-based (unbiased) stereology. In the present study, the total number (N) of IC in rat liver was estimated for the first time, by combining immunocytochemistry with the optical fractionator. Quantification was extended to the hepatocytes, to disclose the IC index, an often-used ratio in hepatology. Systematic uniform random liver sections were obtained from male Wistar rats (n = 3), and immunostained against glial fibrillary acidic protein (GFAP), a known specific marker for hepatic IC. For the first time, these were marked against GFAP in thick (30 μm) paraffin sections. The estimated N of IC was 224E06; with a coefficient of error of 0.04 or 0.06, depending on the particular equation used (based on the so-called "quadratic approximation"). The IC index was 91 IC/1000 hepatocytes. Concerning the lobular heterogeneity, it was proved the liver harbours a larger total number of periportal IC and hepatocytes.

In Situ Semi-Quantitative Analysis of Polluted Soils by Laser-Induced Breakdown Spectroscopy (LIBS)

Time-saving, low-cost analyses of soil contamination are required to ensure fast and efficient pollution removal and remedial operations. In this work, laser-induced breakdown spectroscopy (LIBS) has been successfully applied to in situ analyses of polluted soils, providing direct semi-quantitative information about the extent of pollution. A field campaign has been carried out in Brittany (France) on a site presenting high levels of heavy metal concentrations. Results on iron as a major component as well as on lead and copper as minor components are reported. Soil samples were dried and prepared as pressed pellets to minimize the effects of moisture and density on the results. LIBS analyses were performed with a Nd:YAG laser operating at 1064 nm, 60 mJ per 10 ns pulse, at a repetition rate of 10 Hz with a diameter of 500 μm on the sample surface. Good correlations were obtained between the LIBS signals and the values of concentrations deduced from inductively coupled plasma atomic emission spectroscopy (ICP-AES). This result proves that LIBS is an efficient method for optimizing sampling operations. Indeed, "LIBS maps" were established directly on-site, providing valuable assistance in optimizing the selection of the most relevant samples for future expensive and time-consuming laboratory analysis and avoiding useless analyses of very similar samples. Finally, it is emphasized that in situ LIBS is not described here as an alternative quantitative analytical method to the usual laboratory measurements but simply as an efficient time-saving tool to optimize sampling operations and to drastically reduce the number of soil samples to be analyzed, thus reducing costs. The detection limits of 200 ppm for lead and 80 ppm for copper reported here are compatible with the thresholds of toxicity; thus, this in situ LIBS campaign was fully validated for these two elements. Consequently, further experiments are planned to extend this study to other chemical elements and other matrices of soils.

Improvement of the Identification of Four Heavy Metals in Environmental Samples by Using Predictive Decision Tree Models Coupled with a Set of Five Bioluminescent Bacteria

A primary statistical model based on the crossings between the different detection ranges of a set of five bioluminescent bacterial strains was developed to identify and quantify four metals which were at several concentrations in different mixtures: cadmium, arsenic III, mercury, and copper. Four specific decision trees based on the CHAID algorithm (CHi-squared Automatic Interaction Detector type) which compose this model were designed from a database of 576 experiments (192 different mixture conditions). A specific software, 'Metalsoft', helped us choose the best decision tree and a user-friendly way to identify the metal. To validate this innovative approach, 18 environmental samples containing a mixture of these metals were submitted to a bioassay and to standardized chemical methods. The results show on average a high correlation of 98.6% for the qualitative metal identification and 94.2% for the quantification. The results are particularly encouraging, and our model is able to provide semiquantitative information after only 60 min without pretreatments of samples.

From the Field into the Lab: Useful Approaches to Selecting Species Based on Local Knowledge

Ethnopharmacological field studies are indispensable for identifying plants that can be selected for their pharmacological effects and chemical composition. Although the subjective interpretation of results by the researcher is crucial, quantitative data analysis is a useful tool to identify the most promising pharmacological plants. It has been stated that such semi-quantitative information increases the likelihood of finding promising ethnopharmacological leads, but so far no critical review has assessed what standards best meet the requirements of biomedical research. Systematic database searches using SCOPUS, Science Direct, Web of Knowledge, Science Citation Index, and Medline with the keywords “ethnobotany,” “ethnopharmacology,” “index,” and “consensus” in research from the last 5 years form the basis of the current analysis, which identifies particularly useful tools like factor of informant consensus, fidelity level, use-value, and relative importance. A key feature for further field studies is that they should provide clear information on a range of topics like; detailed data of the importance of these resources within a culture, data of the uses of the species, how and where the plants are collected, drying and storage processes, preparation method, used doses, and administration. In addition, they must include a collection of records about how the people feel after the plant use, disappearance of specific symptoms and possible side effects.

Coding Early Naturalists' Accounts into Long-Term Fish Community Changes in the Adriatic Sea (1800–2000)

The understanding of fish communities' changes over the past centuries has important implications for conservation policy and marine resource management. However, reconstructing these changes is difficult because information on marine communities before the second half of the 20th century is, in most cases, anecdotal and merely qualitative. Therefore, historical qualitative records and modern quantitative data are not directly comparable, and their integration for long-term analyses is not straightforward. We developed a methodology that allows the coding of qualitative information provided by early naturalists into semi-quantitative information through an intercalibration with landing proportions. This approach allowed us to reconstruct and quantitatively analyze a 200-year-long time series of fish community structure indicators in the Northern Adriatic Sea (Mediterranean Sea). Our analysis provides evidence of long-term changes in fish community structure, including the decline of Chondrichthyes, large-sized and late-maturing species. This work highlights the importance of broadening the time-frame through which we look at marine ecosystem changes and provides a methodology to exploit, in a quantitative framework, historical qualitative sources. To the purpose, naturalists' eyewitness accounts proved to be useful for extending the analysis on fish community back in the past, well before the onset of field-based monitoring programs.

Diesel soot oxidation during the late combustion phase

The diesel soot was extracted from the chamber of a running diesel engine using a total cylinder sampling system. A structural description and size distribution of the soot spherules were performed by means of high-resolution transmission electron microscopy (HRTEM). HRTEM image analysis was carried out to achieve semi-quantitative information about the soot organization. Different nanostructures were found in dependence upon the engine test conditions. A better organization of the graphitic layers occurred for the in-cylinder soot as the expansion stroke developed. The oxygen concentrations at sampling angles and the cylinder pressure were measured. The oxidation rates of the in-cylinder soot during the late combustion phase were calculated according to the differences of spherules size distributions between two consecutive sampling angles. The soot reactivity in dependence on the nanostructure was shown after deducting the effect of oxygen concentration and temperature. The increase of resistance toward oxidation was associated to the increase of the structural order for the in-cylinder soot. The results are a useful database for testing the structure–property relationship between the nanostructure and the reactivity of the in-cylinder diesel soot.

Pyrosequencing faecal DNA to determine diet of little penguins: is what goes in what comes out?

DNA barcoding of faeces or stomach contents is an emerging approach for dietary analysis. We pyrosequenced mtDNA 16S markers amplified from faeces of captive little penguins (Eudyptula minor) to examine if recovered sequences reflect the proportions of species consumed. We also analysed wild little penguin faeces collected from 100 nests in southeast Australia. In the captive study, pilchards were the primary fish fed to the penguins and DNA sequences from pilchard were the most common sequences recovered. Sequences of three other fish fed in constant mass proportions (45:35:20) were all detected, but proportions of sequences (60:6:34) were considerably different than mass proportions in the diet. Correction factors based on relative mtDNA density in the fish did not improve diet estimates. Consistency between replicate samples suggests that the observed bias resulted from differences in prey digestibility. Detection of DNA from fish consumed before the penguins were brought into captivity indicates that a DNA signal in faeces can persist for at least 4 days after ingestion. In the wild-collected faeces, 24 distinct fish and 1 squid were identified; anchovy, barracouta and pilchard accounted for over 80% of these sequences. Our results highlight that DNA sequences recovered in dietary barcoding studies can provide semi-quantitative information on diet composition, but these data should be given wide confidence intervals.

Ultra-High Performance Liquid Chromatography−Mass Spectrometry for the Fast Profiling of Histone Post-Translational Modifications

Histones are subjected to extensive post-translational modifications (PTMs) that are known to play key roles in many biological processes. In this study, we report a fast, efficient, highly reproducible, and easily automated method involving ultra-high performance liquid chromatography (UHPLC) coupled to a high resolution/high mass accuracy LTQ-Orbitrap mass spectrometer to profile core histone modifications/variants from WI-38 primary human fibroblasts. The whole analysis was performed on intact unfractionated histones within 19 min, which is ∼3-fold faster than previously published procedures. High mass accuracy measurements combined with top-down tandem mass spectrometry (MS) experiments enable accurate histone identification. Experimental and biological variations were thoroughly assessed and were 8% and 16% on average, respectively. With a sample preparation reduced to the minimum, characterization of the most abundant histones can be achieved in a single experiment. Semi-quantitative information can be obtained with respect to the relative abundances of the detected isoforms through a label-free approach. Isoform identities and relative distributions were further confirmed by the LC-MS/MS analysis of tryptic digests. Overall, our UHPLC-MS approach for histone profiling offers a sensitive and reproducible tool that will be of great value for exploring PTMs and variants and can readily be applied to clinical or pharmaceutical studies.

ChemInform Abstract: Reactions of Transition Metal Clusters with Small Molecules

Atoms and small molecules react with transition metal clusters in ways that are analogous to the physisorption and chemisorption reactions observed on the corresponding extended metal surface. However, often underlying these similarities are size-dependent variations in the reaction mechanisms and rates, the interpretation of which requires a detailed understanding of the structures of both the bare metal cluster substrates and the cluster-molecule complexes. Although polyatomic transition metal clusters cannot be characterized by the traditional methods of molecular spectroscopy, the combination of other physical and chemical probes can provide qualitative and semiquantitative structural information. These techniques, when combined with equilibrium geometries calculated using ab initio or semiempirical methods, provide a detailed picture of the structural origin of metal cluster reactivity and its variation with size.

Direct analysis of pharmaceutical tablet formulations using matrix‐assisted laser desorption/ionisation mass spectrometry imaging

Matrix-Assisted Laser Desorption/Ionisation Mass Spectrometry Imaging (MALDI MSI) has been used to directly analyse a range of tablets in order to assess the homogeneity of the active drug compound throughout the excipients contained within the tablets studied. The information gained from the imaging experiments can be used to improve and gain a greater understanding of the manufacturing process; such knowledge will enable improvements in finished product quality to make safer and more efficacious tablet formulations. Commercially available and prescription tablet formulations have been analysed, including aspirin, paracetamol, sildenafil citrate (Viagra(R)) and a batch of tablets in development (tablet X: placebo; 1 mg; 3 mg and 6 mg). MALDI MSI provides semi-quantitative information that is related to ion abundance, therefore Principal Component Analysis (PCA), a multivariate analysis technique, has been used to differentiate between tablets containing different amounts of active drug ingredient. Aspects of sample preparation have also been investigated with regard to tablet shape and texture. The results obtained indicate that MALDI MSI can be used effectively to analyse the spatial distribution of the active pharmaceutical component (API) in pharmaceutical tablet formulations.

Generalisation of a procedure for computing transcription factor profiles

The limited amount of quantitative experimental data generated from life-science experiments poses a major challenge in systems biology. The reason for this is that many systems approaches, such as parameter estimation, simulation and sensitivity analysis make use of models or analyse quantitative data. However, these techniques are only of limited use if only qualitative or semi-quantitative information is available about a system. Therefore procedures that generate quantitative data from experiments in the life sciences can greatly expand the use of systems approaches to biological problems. This study addresses this issue as it introduces a procedure that computes quantitative transcription factor profiles from fluorescent microscopy data collected from green fluorescent protein (GFP) reporter cells. This technique forms a generalisation of a method that has recently been introduced for monitoring NF-B profiles. The contribution made in this work is that the assumption that the transcription factor profile exhibits damped oscillations is relaxed, as transcription factors, other than the previously investigated NF-B, may exhibit different profiles. This is achieved by investigating a variety of potential profiles and solving the inverse problem for the model describing transcription, translation and activation of GFP for each one. The transcription factor profile that results in the best fit among the potential candidates, for the measured fluorescent intensity data, is then chosen as the most likely concentration profile. The technique is illustrated in two detailed case studies, where one case study involves simulation data whereas the other one uses experimentally derived fluorescent intensity data.

Application of classical and new, direct analytical methods for the elucidation of ion movements during the redox transformation of polypyrrole

Redox transformation and related processes in conjugated polymers have been studied by both classical (electrochemical quartz crystal nanogravimetry, in situ optical electrochemistry and a. c. impedance technique) and modern, direct analytical methods. As a model, polypyrrole thin layers have been deposited on a double-band indium tin oxide-supporting electrode—for the first time in the literature. The structure of the printed circuit made possible to monitor simultaneously the electrochemical, the optical, and the conductance changes during the processes, occurring in the self-same film. The film has been deposited under similar conditions on a quartz crystal-supported platinum electrode, as well, to follow the mass changes. The oxidation state of the layers has been gradually modified by multiple potential steps, and the abovementioned measurements have been completed by elementary analysis performed by energy dispersive X-ray (EDX) spectroscopy. From the correlation of the results, obtained by independent methods, the mixed anionic and cationic charge compensation has been evidenced. While during the first part of the oxidation (−0.6 V to 0.0 V) cations are removed from the layer, in the second part (0.0 V-0.8 V) the anion incorporation is dominant. The results prove that EDX measurements can deliver direct semi-quantitative information on ion exchange processes accompanying the doping-undoping of conducting polymers.

Application of a Liquid Extraction Based Sealing Surface Sampling Probe for Mass Spectrometric Analysis of Dried Blood Spots and Mouse Whole-Body Thin Tissue Sections

The utility of a liquid extraction based sealing surface sampling probe (SSSP) for the direct mass spectrometric analysis of targeted drugs and metabolites in dried blood spots (DBSs) and whole mouse thin tissue sections was demonstrated. The accuracy and precision for the quantitative analysis of a minimum of 50 ng/mL sitamaquine or acetaminophen in DBSs on paper were well within the required 15% dictated by internationally recognized acceptance criteria for assay validations. Analysis of whole-body mouse thin tissue sections from animals dosed with propranolol, adhered to an adhesive tape substrate, provided semiquantitative information for propranolol and its hydroxyproranolol glucuronide metabolite within specific organs of the tissue. The relative abundances recorded for the two compounds in the brain, lung, kidney, and liver were in nominal agreement with previously reported amounts based on analysis using a liquid microjunction surface sampling probe (LMJ-SSP), whole-body autoradiography (WBA), and high-pressure liquid chromatography-mass spectrometry (HPLC-MS). The ability to sample and analyze from tape-adhered tissue samples, which are generally employed in WBA analysis, presents the possibility of consecutive WBA and SSSP-MS analysis of the same tissue section. This would facilitate assignment, and possibly quantitation, of the different molecular forms of total drug related material detected in the WBA analysis. The flexibility to sample larger or smaller spot sizes, alternative probe sealing mechanisms, and a reduction in internal volumes and associated sample carryover issues will be among the first simple improvements necessary to make the SSSP-MS method a practical DBS and/or thin tissue section analysis tool or to expand its use to other surface sampling applications.

Rapid Raman Imaging of Stable, Functionalized Nanoshells in Mammalian Cell Cultures

Two Raman-active poly(ethylene glycol) (PEG) molecules, one linear (MW 5000) and the other branched (MW 2420), are synthesized to stabilize gold-silica nanoshells in cell culture media and track nanoparticles in mammalian cell cultures. The linear PEG provides greater nanoshell stability in saline solution compared to commercially available PEG-thiol or the branched PEG. Surface enhanced Raman scattering rapidly tracks the probes and provides semiquantitative information regarding particle localization within mouse macrophage (RAW 264.7) and human breast cancer (MCF 7) cell cultures.

Relating soil carbon fractions to land use in sloping uplands in northern Thailand

In this study from Khun Samun Watershed in northern Thailand we investigate land use and soil carbon relationships in 99 sloping upland soils that pertain to soil degradation/conservation and carbon storage/loss. Approximately 35% of the variability in total soil carbon could be explained by the available quantitative and semi-quantitative information, primarily clay content and CEC, and to a lesser degree by factors concerning land management. When categorical information such as land-use class and location was included, the explanatory power increased to 65% for total soil carbon, whereas for particulate and soluble carbon fractions the model predicted 71–95% of the total variability. The water soluble carbon fractions were high in systems with input of high C-to-N ratio material, whereas the permanganate oxidizable fraction was somewhat increased in the predominantly anoxic wetland rice site, and in fruit tree plantations. Coarse particulate organic matter carbon was strongly affected by land use. A causal relationship between land use and soil carbon or carbon fractions cannot be firmly established since historical data from these soils are lacking, but the significance of the various carbon fractions is discussed. It is proposed that the communities have selected land for particular purposes based on suitability, i.e. perceived inherent quality, accessibility and possibly other factors. Thus, the best land is apt to be used for the cultivation of fruit trees, teak and annual crops, leaving the poorest land for secondary forest. This study did not indicate that the cultivation of land is rapidly degrading the soil quality, either by carbon content, carbon fractions, or the profile gradients of total carbon or particulate carbon through the topsoil (0–20 cm). Profile carbon gradients were significantly explained by land-use class, but not by the position in the landscape which indicates that erosion is not an overriding force. While the secondary forest had the strongest profile gradient of total carbon, it was not much higher than fallow and fruit tree plantations, and only significantly different from wetland rice, which had a very small gradient due to the frequent ploughing of the soil. The similarities in profile carbon gradients is ascribed to the actual land management, where planting of crops is commonly done by punching holes in the otherwise undisturbed topsoil, and subsequent weeding is done by manual slashing or with herbicides, thus effectively forming a zero-till practice.

A Novel 18 F-Labeled Tracer for the Quantification of Myocardial Blood Flow and Infarct Size With Positron-Emission Tomography

Currently, nuclear imaging techniques can be used to diagnose coronary macrovascular and microvascular disease and to measure infarct size and left ventricular ejection fraction. Semiquantitative assessment of regional myocardial perfusion with single-photon emission computed tomography is a noninvasive, robust, and widely available method of assessing myocardial ischemia and has an established role in the clinical setting.1 A great number of studies have assessed the sensitivity and specificity of this technique for the detection of coronary artery disease (CAD), with coronary arteriography usually being used as the standard by which the accuracy of scintigraphy is judged.1 The main limitation of single-photon emission computed tomography perfusion imaging is that it provides only semiquantitative information on the regional distribution of myocardial blood flow (MBF). This is particularly relevant in conditions in which MBF and coronary flow reserve (CFR) are diffusely abnormal, (eg, in patients with hypertrophic and dilated cardiomyopathies).2 Article p 77 The ability to make quantitative measurements of MBF with positron-emission tomography (PET) allows determination of the functional significance of epicardial coronary lesions. In patients with single-vessel CAD, chronic stable angina, and no previous history of myocardial infarction (MI), CFR in response to a standard dose of dipyridamole was found to be markedly reduced in the myocardial regions subtended by the stenosed coronary artery compared with regions subtended by angiographically normal vessels.3 Using H215O or 13NH3 with PET, the relationship between stenosis severity, measured by quantitative coronary angiography, and its consequences on regional MBF and CFR has been …

Dynamic secondary ion mass spectrometry and X-ray photoelectron spectroscopy on artistic bronze and copper artificial patinas

To prevent the natural processes of decay and to develop and improve the treatments of conservation and restoration of artistic bronzes meaning statues and sculptures, it is important understanding the patination processes and the knowledge of artificially corroded surfaces. Chemical and physical characterization of artificial patinas obtained on artistic bronzes and coppers by using the 19th century Western traditional patination techniques and recipes by means of SEM–EDS, light microscopy and ATR/FT-IR has been done in previous studies [I.Z. Balta, L. Robbiola, Characterization of artificial black patinas on artistic cast bronze and pure copper by using SEM–EDS and light microscopy, in: Proceedings of the 13th European Microscopy Congress, 22–27 August 2004, Antwerp, Belgium, EMC 2004 CD-Rom Conference Preprints; I.Z. Balta, L. Robbiola, Traditional artificial artistic bronze and copper patinas—an investigation by SEM–EDS and ATR/FT-IR, in: Proceedings of the 8th International Conference on Non Destructive Investigations and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage, 15–19 May 2005, Lecce, Italy, ART’05 CD-Rom Conference Preprints]. Differences in morphology (structure, thickness, porosity, adherence, compactity, uniformity, homogeneity) and also in composition, on both artistic cast bronze and pure copper patinas, were clearly evidenced. Further in-depth investigation is required to be carried out in order to better understand the patinas mechanisms of formation and the layers kinetics of growth. The elemental and chemical analysis, either on a surface monolayer or in a depth profile, by using the Secondary Ion Mass Spectrometry (SIMS) and X-ray Photoelectron Spectroscopy (XPS) techniques, can provide this kind of information, unique at trace-level sensitivity. SIMS has proved to be a suitable analytical technique for analyzing small amounts of material with high atomic sensitivity (ppm or even ppb) and high depth/lateral resolution in the micron and sub-micron range [R.G. Wilson, F.A. Stevie, C.W. Magee, Secondary Ion Mass Spectrometry: A Practical Handbook for Depth Profiling and Bulk Impurity Analysis, Wiley & Sons, New York, 1989; M. Dowsett, A. Adriaens, The role of SIMS in cultural heritage studies, Nucl. Instr. Meth. Phys. Res. B 226 (2004) 38–52]. XPS has the ability to provide detailed chemical information on virtually each kind of solid sample, and elemental identification is therefore possible due to the core level photoemission. The most important advantage is the high surface sensitivity of the chemical information (a few monolayers) [E. Ciliberto, G. Spoto, Modern Analytical Methods in Art and Archaeology, John Wiley & Sons, Inc., New York, 2000]. In addition elements’ relative abundance can be made semi-quantitative or quantitative and information on chemical bonds can be derived. The aim of the present work is to highlight the advantages and the limits of XPS and Dynamic SIMS surface analytical techniques for the characterization of artistic bronze and copper artificial patinas. The results obtained on the analyzed samples allowed the distribution of the main elements in the corrosion patinas layers and the contribution of each elements present in bronze matrix to the color of the resulting patinas to be precisely revealed. This information could be used for comparative studies between artificial and natural patinas, and also for provenience and authentication studies for artistic and archaeological bronzes.

Visual assessment of soil structure: Evaluation of methodologies on sites in Canada, China and Germany: Part I: Comparing visual methods and linking them with soil physical data and grain yield of cereals

Visual observations of soil structure in the field offer the potential of semi-quantitative information for use in extension and monitoring. The aim of the study was to test the diagnostic value of different visual methods of soil structure assessment in relation to measurements of topsoil physical quality and yield of cereals. Visual methods that emphasized aggregate and pore characteristics were considered and included procedures of Peerlkamp [Peerlkamp, P.K., 1967. Visual estimation of soil structure. In: de Boodt, M., de Leenherr, D.E., Frese, H., Low, A.J., Peerlkamp, P.K. (Eds.), West European Methods for Soil Structure Determination, vol. 2, no. 11. State Faculty Agric. Sci., Ghent, Belgium, pp. 216–223], Diez and Weigelt [Diez, T., Weigelt, H., 1997. Bodenstruktur erkennen und beurteilen. Anleitung zur Bodenuntersuchung mit dem Spaten. Sonderdruck diz agrarmagazin. Bayer. Landesanstalt fuer Bodenkultur und Pflanzenbau, Freising-Muenchen., 2nd ed., 16 pp.], Shepherd [Shepherd, T.G., 2000. Visual Soil Assessment. Volume 1. Field Guide for Cropping and Pastoral Grazing on Flat to Rolling Country. Horizons.mw/Landcare Research, Palmerston North, 84 pp.], Werner and Thaemert [Werner, D., Thaemert, W., 1989. Zur Diagnose des physikalischen Bodenzustandes auf Produktionsflaechen. Arch. Acker-Pflanzenbau Bodenkd., Berlin 33, 729–739], FAO [FAO, 2006. Guidelines for soil description, 4th ed. FAO, Rome, 95 pp.] and the Peerlkamp method, modified by [Ball, B.C., Batey, T., Munkholm, L.J., 2007. Field assessment of soil structural quality—a development of the Peerlkamp test. Soil Use and Management 23, 329–337]. Measurements of soil quality included soil density (DBD), strength (penetrometer resistance, vane shear strength), permeability (initial infiltration rate) and biological activity (earthworm counts). The study was conducted on sites in Canada (Elora), China (Luancheng), and Germany (Dedelow). Soils were loamy and silty textured Haplic Luvisols (Elora, Dedelow) and Haplic Cambisols (Luancheng). Results showed that shape and size of aggregates were quickly recognizable diagnostic features of soil structure. Structure scores of most methods gave similar results after standardizing data. Measured soil physical qualities and crop yields correlated significantly with visual soil structure. Unfavourable visual structure was associated with increased dry bulk density, higher soil strength and lower infiltration rate but correlations were site-specific. Biological features like earthworm or root numbers were less reliable indicators of soil structure than aggregate characteristics. Visual soil structure assessment is a useful diagnostic tool and may indicate soil structure states clearly. Methods should be selected according to site conditions and should include a fast method of the Peerlkamp type.

Detection of Diethyl Phthalate in Perfumes by Extractive Electrospray Ionization Mass Spectrometry

Recent findings suggest that long-term exposure to diethyl phthalate (DEP), one of the widely used phthalate esters, can lead to serious health problems. Most perfumes contain non-negligible amounts of DEP. Rapid and sensitive detection of DEP in perfumes is thus of increasing importance. A novel procedure based on extractive electrospray ionization mass spectrometry (EESI-MS) has been developed for fast detection and identification of DEP in perfumes without the need for any sample pretreatment. The limit of determination for DEP in perfume was less than 100 ppb using tandem mass spectrometry on a commercial quadrupole time-of-flight mass spectrometer. The dynamic range of this method was about 4 orders of magnitude. A single sample analysis was completed within a few seconds, providing a rapid way to obtain semiquantitative information on the DEP content in perfumes. This study shows that both volatile and nonvolatile analytes (e.g., amino acids) in liquids can be directly sampled by neutral desorption, providing a convenient way for high-throughput screening of target compounds using EESI-MS.

Anisotropic Crystal Plasticity Finite Element Modeling of the Effect of Crystal Orientation and Solder Joint Geometry on Deformation after Temperature Change

The crystal orientation of the tin phase in a Pb-free Sn solder joint has a significant effect on the stress state, and hence on the reliability of the solder joint. A set of crystal plasticity analyses was used to evaluate stress and strain resulting from a 165°C temperature change in a single-crystal joint using two simplified geometries used in practical solder joints. Phenomenological flow models for ten slip systems were estimated based upon semiquantitative information available in the literature, along with known anisotropic elastic property information. The results show that the internal energy of the system is a strong function of the tin crystal orientation and geometry of the solder joint. The internal energy (and presumably the likelihood of damage) is highest when the crystal c-axis lies in the plane of the substrate, leading to significant plastic deformation. When the a-axis is in the plane of the interface, deformation due to a 165°C temperature change is predominantly elastic. The texture of the copper substrate using isotropic Cu elastic properties, or anisotropic elastic properties with [001] $$ \parallel $$ substrate normal direction, does␣not have a significant effect on the stress or strain in the Sn phase of the joint.