A framework for quantifying environmental sustainability

Recent concepts of environmental sustainability have focused on narrative economic and societal aspects rather than quantitative ones. Many key sustainability indicators also lack a consistent definition of sustainability, have perspectives that are too short-term, and are unable to model the dynamics of complex environmental utilization which can then result in inappropriate projection of long-term sustainability and/or sustainability indication. Here I propose a generalized quantitative framework of environmental sustainability requiring that (1) environmental capacities and utilization rates are identified, (2) their complex temporal dynamics are quantitatively modeled or estimated (3) while also adjusting for uncertainties, and finally, (4) using one of three options, determining which cumulative utilization pathways can be sustained for a (usually well-defined) period of time. Using the example of wood volume and its growth as capacities and harvest as utilization, and the example of global greenhouse gas emissions as the utilization component and the capacity of the air to absorb these emissions, I demonstrate how the proposed framework can be applied in practice, how sustainability indicators could be developed, and also how they can inform policies and measures to ensure sustainability.     

Comparison of label-free methods for quantifying human proteins by shotgun proteomics

Measurements of mass spectral peak intensities and spectral counts are promising methods for quantifying protein abundance changes in shotgun proteomic analyses. We describe Serac, software developed to evaluate the ability of each method to quantify relative changes in protein abundance. Dynamic range and linearity using a three-dimensional ion trap were tested using standard proteins spiked into a complex sample. Linearity and good agreement between observed versus expected protein ratios were obtained after normalization and background subtraction of peak area intensity measurements and correction of spectral counts to eliminate discontinuity in ratio estimates. Peak intensity values useful for protein quantitation ranged from 10(7) to 10(11) counts with no obvious saturation effect, and proteins in replicate samples showed variations of less than 2-fold within the 95% range (+/-2sigma) when >or=3 peptides/protein were shared between samples. Protein ratios were determined with high confidence from spectral counts when maximum spectral counts were >or=4 spectra/protein, and replicates showed equivalent measurements well within 95% confidence limits. In further tests, complex samples were separated by gel exclusion chromatography, quantifying changes in protein abundance between different fractions. Linear behavior of peak area intensity measurements was obtained for peptides from proteins in different fractions. Protein ratios determined by spectral counting agreed well with those determined from peak area intensity measurements, and both agreed with independent measurements based on gel staining intensities. Overall spectral counting proved to be a more sensitive method for detecting proteins that undergo changes in abundance, whereas peak area intensity measurements yielded more accurate estimates of protein ratios. Finally these methods were used to analyze differential changes in protein expression in human erythroleukemia K562 cells stimulated under conditions that promote cell differentiation by mitogen-activated protein kinase pathway activation. Protein changes identified with p<0.1 showed good correlations with parallel measurements of changes in mRNA expression.     

Comparison of two techniques for assessing possum (

Two techniques for assessing possum (Trichosurus vulpecula Kerr) diet from stomach contents ("point-sampling" and "layer- separation") are described and compared. Point-sampling involves sieving stomach contents, systematically selecting fragments from the retained material then, identifying and weighing these. Layer-separation involves separation, identification, and weighing of the discrete layers apparent in most possum stomach contents. In 41 of 43 stomachs examined, we were able to separate discrete layers that nearly always comprised a single food item. To compare the two techniques both were applied to these 41 stomachs, with the point-sampling technique applied as two separate treatments using 1.4-mm and 2.0-mm sieves. There were major differences in diet composition estimates between layer-separation and point-sampling but with few differences between the two point-sampling treatments. Relative to layer-separation, point-sampling underestimated the proportions of food groups with small average fragment size and overestimated those with large fragment size. However, both techniques gave similar frequencies of occurrence for 8 of 10 food groups tested, although the apparent importance of foods based on ranking by frequency of occurrence did not accurately match the ranking based on percent composition data. Identification of material was usually easier and more complete with layer-separation than with point-sampling (i.e., there were virtually no unidentifiable stems and fibre after layer- separation). Layer-separation therefore appears likely to provide a simple technique for diet assessment in possums. Although the technique requires formal validation the existence of layers shows that there can have been little mixing (or digestion) of stomach contents, and therefore, that the layer- separation estimates cannot differ greatly from what was eaten. Techniques that involve sieving possum stomach contents appear to have serious limitations, but may be useful as a last resort when layers contain a mixture of foods, or for stomachs in which the layers are not distinguishable.     

Nanomaterial enabled sensors for environmental contaminants

The need and desire to understand the environment, especially the quality of one’s local water and air, has continued to expand with the emergence of the digital age. The bottleneck in understanding the environment has switched from being able to store all of the data collected to collecting enough data on a broad range of contaminants of environmental concern. Nanomaterial enabled sensors represent a suite of technologies developed over the last 15 years for the highly specific and sensitive detection of environmental contaminants. With the promise of facile, low cost, field-deployable technology, the ability to quantitatively understand nature in a systematic way will soon be a reality. In this review, we first introduce nanosensor design before exploring the application of nanosensors for the detection of three classes of environmental contaminants: pesticides, heavy metals, and pathogens.     

Comparison of two techniques for diagnosis of giardiasis in dogs

Giardiasis is an intestinal parasitosis affecting dogs and able to infect human beings. Its diagnosis can not be done with the only clinical signs, the main of which is non characteristic diarrhoea. It implicates to perform further tests to detect the parasite. The zinc sulfate concentration technique (ZSCT) is the more effective one if performed on two or three successive days. Fecal ELISA kits have been developed to detect Giardia in humans and were found to be less sensitive than the ZSCT in dogs. In this study, we used 30 infected Beagles to compare the sensitivity of one, two or three fecal examinations following ZSCT and one or two ELISA tests. We conclude that if a single ZSCT is insufficient, two or three ZSCT and one or two ELISA using the commercial kit ProSpecT Giardia have almost the same sensitivity.     

Infrared techniques for quantifying protein structural stability

Biopharmaceutical and biotechnology companies and regulatory agencies require novel methods to determine the structural stabilities of proteins and the integrity of protein-protein, protein-ligand, and protein-membrane interactions that can be applied to a variety of sample states and environments. Infrared spectroscopy is a favorable method for a number of reasons: it is adequately sensitive to minimal sample amounts and is not limited by the molecular weight of the sample; yields spectra that are simple to evaluate; does not require protein modifications, a special supporting matrix, or internal standard; and is applicable to soluble and membrane proteins. In this paper, we investigate the application of infrared spectroscopy to the quantification of protein structural stability by measuring the extent of amide hydrogen/deuterium exchange in buffers containing D₂O for proteins in solution and interacting with ligands and lipid membranes. We report the thermodynamic stability of several protein preparations, including chick egg-white lysozyme, trypsin bound by benzamidine inhibitors, and cytochrome c interacting with lipid membranes of varying net-negative surface charge density. The results demonstrate that infrared spectroscopy can be used to compare protein stability as determined by amide hydrogen/deuterium exchange for a variety of cases.     

Comparison of two surgical techniques for mastectomy of goats

Two different techniques for mastectomy were carried out on 14 goats with gangrenous mastitis. The animals were randomly assigned to one of two groups containing seven goats each. The first group was operated via a classical surgical mastectomy technique (either bilateral (n=5) or unilateral (n=2)). The second group was operated via vascular ligation of the external pudendal blood vessels and milk vein and amputation of the affected teat (either bilateral (n=3) or unilateral (n=4)). Comparison between the two groups was carried out. Vascular ligation and teat amputation proved to be an effective, quick, safe, and less expensive technique for mastectomy in goats. Ligation of udder vasculature was less traumatic than surgical amputation and the stress on the patient was minimal.     

福氏志贺菌两种血清分型方法的比较

目的评价福氏志贺菌两种血清分型方法。方法使用传统血清分型方法和多重PCR血清分型方法对255株福氏志贺菌进行血清型分析。结果传统血清分型方法的分型率为98.4%(251/255),多重PCR血清分型方法分型率为96.1%(245/255),两种方法的分型率经卡方检验,差异无统计学意义(χ2=2.644,P>0.05)。有46株菌(18.0%,46/255)通过这两种血清分型得到的结果不一致。结论两种血清分型方法的分型率差异无统计学意义,但部分结果判断有不同。多重PCR更适用于大量样本的检测,传统血清分型方法可以与其互为补充。     

Measuring stress in wildlife: techniques for quantifying glucocorticoids

Stress responses play a key role in allowing animals to cope with change and challenge in the face of both environmental certainty and uncertainty. Measurement of glucocorticoid levels, key elements in the neuroendocrine stress axis, can give insight into an animal’s well-being and can aid understanding ecological and evolutionary processes as well as conservation and management issues. We give an overview of the four main biological samples that have been utilized [blood, saliva, excreta (feces and urine), and integumentary structures (hair and feathers)], their advantages and disadvantages for use with wildlife, and some of the background and pitfalls that users must consider in interpreting their results. The matrix of choice will depend on the nature of the study and of the species, on whether one is examining the impact of acute versus chronic stressors, and on the degree of invasiveness that is possible or desirable. In some cases, more than one matrix can be measured to achieve the same ends. All require a significant degree of expertise, sometimes in obtaining the sample and always in extracting and analyzing the glucocorticoid or its metabolites. Glucocorticoid measurement is proving to be a powerful integrator of environmental stressors and of an animal’s condition.     

Aptamer-based environmental biosensors for small molecule contaminants

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Comparison of two histological techniques for age determination in small cetaceans

Age estimation in odontocetes is based on counts of growth layer groups (GLGs) deposited in recording structures such as teeth. Generally, tooth sections are obtained using a cryostat microtome. However, some researchers prefer obtaining thin sections using a traditional paraffin microtome. Little information is available on the application of this technique to dolphin teeth. Our main aim was to investigate if the paraffin technique can be a viable alternative. We considered whether estimated age would be affected by preparation technique, staining method, and section thickness, while controlling for effects of species, body length, and sex. We also analyzed whether the staining method would affect readability of GLGs and age reading variability. Teeth from 86 individuals (representing seven species) were used, but not all were prepared using both techniques because sufficient teeth were not available in all cases. Although the staining method had significant effects on the estimated age using both techniques, the variability of GLG counts was small and appeared to be similar for both techniques. Using Mayer's hematoxylin stained sections of 8 μm thickness, good agreement of ages was obtained from both techniques, with more preparations classified as "good quality" for the paraffin technique. Mayer's hematoxylin provided the best contrast of the GLGs when using the paraffin technique. We conclude that the paraffin technique is viable and represents a cost-effective alternative to a cryostat microtome when preparing cetacean teeth for age determination.     

检测环境污染物的适配体生物传感器研究进展

适配体生物传感器可利用适配体作为识别元件,将适配体的优良特性和目前先进的检测技术进行结合,例如光学、电化学纳米集成技术或生物膜干涉测量法,为其在有毒有害物质检测和环境实时监测领域构筑了良好应用前景。然而,适配体传感器的进一步应用仍有许多问题亟待解决,比如:环境的复杂性会对其应用产生限制;适配体固化到传感器表面的方式会影响适配体的结构和功能,从而影响检测效果。本文将主要研究适配体筛选策略的最新进展并对适配体传感器检测环境中小分子污染物的应用展开综述。     

Comparison of alternative analytical techniques for the characterisation of the human serum proteome in HUPO Plasma Proteome Project

Based on the same HUPO reference specimen (C1-serum) with the six proteins of highest abundance depleted by immunoaffinity chromatography, we have compared five proteomics approaches, which were (1) intact protein fractionation by anion-exchange chromatography followed by 2-DE-MALDI-TOF-MS/MS for protein identification (2-DE strategy); (2) intact protein fractionation by 2-D HPLC followed by tryptic digestion of each fraction and microcapillary RP-HPLC/microESI-MS/MS identification (protein 2-D HPLC fractionation strategy); (3) protein digestion followed by automated online microcapillary 2-D HPLC (strong cation-exchange chromatography (SCX)-RPC) with IT microESI-MS/MS; (online shotgun strategy); (4) same as (3) with the SCX step performed offline (offline shotgun strategy) and (5) same as (4) with the SCX fractions reanalysed by optimised nanoRP-HPLC-nanoESI-MS/MS (offline shotgun-nanospray strategy). All five approaches yielded complementary sets of protein identifications. The total number of unique proteins identified by each of these five approaches was (1) 78, (2) 179, (3) 131, (4) 224 and (5) 330 respectively. In all, 560 unique proteins were identified. One hundred and sixty-five proteins were identified through two or more peptides, which could be considered a high-confidence identification. Only 37 proteins were identified by all five approaches. The 2-DE approach yielded more information on the pI-altered isoforms of some serum proteins and the relative abundance of identified proteins. The protein prefractionation strategy slightly improved the capacity to detect proteins of lower abundance. Optimising the separation at the peptide level and improving the detection sensitivity of ESI-MS/MS were more effective than fractionation of intact proteins in increasing the total number of proteins identified. Overall, electrophoresis and chromatography, coupled respectively with MALDI-TOF/TOF-MS and ESI-MS/MS, identified complementary sets of serum proteins.     

Comparison of two methods for measuring human serum immunoglobulins (laser-nephelometry and radial immunodiffusion)

The AA. have tested 50 serum samples for immunoglobulins (IgG, IgA, IgM) with two different methods: laser-nephelometry (LN) and radial immunodiffusion (RID). Mean values of IgG and IgA are almost the same in the two tested methods and there is a good correlation between LN and RID (IgG: r = 0,98; IgA: = 0,96). Also IgM have showed a good correlation (r = 0,987) but mean values obtained with LN are just a few lower than those obtained with RID. Regression lines, calculated for all the Ig, confirm these conclusions. The AA. conclude affirming that the obtained difference for IgM is due to the different standards used for LN and RID determinations.     

Comparison of two direct-count techniques for enumerating aquatic bacteria.

Planktonic bacteria from an estuary were concentrated on membrane filters and counted with both a scanning electron microscope and an epi-illuminated fluorescent microscope. Counts on 0.2 micron Nuclepore filters (polycarbonate) were significantly higher (P less than 0.001) than counts on 0.2-micron Sartorius filters (cellulose). In contrast, there was not a statistically significant difference between the two techniques when Nuclepore filters were used (0.5 less than P less than 0.9). The average cell volume from this study area was 0.047 micron3. The estimated number of bacteria ranged from 10(6) to 10(7) bacteria per ml, representing from 4 to 40 mg of C per m3.     

Comparison of two direct-count techniques for enumerating aquatic bacteria.

Planktonic bacteria from an estuary were concentrated on membrane filters and counted with both a scanning electron microscope and an epi-illuminated fluorescent microscope. Counts on 0.2 micron Nuclepore filters (polycarbonate) were significantly higher (P less than 0.001) than counts on 0.2-micron Sartorius filters (cellulose). In contrast, there was not a statistically significant difference between the two techniques when Nuclepore filters were used (0.5 less than P less than 0.9). The average cell volume from this study area was 0.047 micron3. The estimated number of bacteria ranged from 10(6) to 10(7) bacteria per ml, representing from 4 to 40 mg of C per m3.     

Comparison of two techniques for obtaining endometrial bacteriologic cultures in the mare

The endometria of 39 mares were cultured simultaneously using a swab guarded with a double cannula and distal, teflon plug and an unguarded swab with a single, open cannula. Sheep blood (5%) agar, Mac-Conkey's agar, and Sabourad's agar media were innoculated with each swab. The presence of bacterial or fungal growth was determined after 24 and 48 hours of aerobic incubation at 37 C. There were significantly more plates that failed to yield bacterial or fungal growth when streaked with swab specimens obtained with the guarded cannula than when streaked with those obtained with the unguarded cannula. It was concluded that while culturing the endometrium of mares for bacteria or fungi, the use of a guarded instrument consisting of a double cannula with a closed end will result in the recovery of fewer contaminants; therefore, it will be more likely to result in a more accurate representation of uterine bacterial and fungal flora.     

Evaluation of two methods for quantifying passeriform lice

Two methods commonly used to quantify ectoparasites on live birds are visual examination and dust‐ruffling. Visual examination provides an estimate of ectoparasite abundance based on an observer's timed inspection of various body regions on a bird. Dust‐ruffling involves application of insecticidal powder to feathers that are then ruffled to dislodge ectoparasites onto a collection surface where they can then be counted. Despite the common use of these methods in the field, the proportion of actual ectoparasites they account for has only been tested with Rock Pigeons (Columba livia), a relatively large‐bodied species (238–302 g) with dense plumage. We tested the accuracy of the two methods using European Starlings (Sturnus vulgaris; ～75 g). We first quantified the number of lice (Brueelia nebulosa) on starlings using visual examination, followed immediately by dust‐ruffling. Birds were then euthanized and the proportion of lice accounted for by each method was compared to the total number of lice on each bird as determined with a body‐washing method. Visual examination and dust‐ruffling each accounted for a relatively small proportion of total lice (14% and 16%, respectively), but both were still significant predictors of abundance. The number of lice observed by visual examination accounted for 68% of the variation in total abundance. Similarly, the number of lice recovered by dust‐ruffling accounted for 72% of the variation in total abundance. Our results show that both methods can be used to reliably quantify the abundance of lice on European Starlings and other similar‐sized passerines.