bluuebunny/crossref_metadata_2025 huggingface dataset:
Restoration of dietary-fat induced blood–brain barrier dysfunction by anti-inflammatory lipid-modulating agents
Authors: Pallebage-Gamarallage Menuka , Lam Virginie , Takechi Ryusuke , Galloway Susan , Clark Karin , Mamo John
Published: September 2012

Background

Several studies have identified use of non-steroidal-anti-inflammatory drugs and statins for prevention of dementia, but their efficacy in slowing progression is not well understood. Cerebrovascular disturbances are common pathological feature of Alzheimer’s disease. We previously reported chronic ingestion of saturated fatty acids (SFA) compromises blood–brain barrier (BBB) integrity resulting in cerebral extravasation of plasma proteins and inflammation. However, the SFA-induced parenchymal accumulation of plasma proteins could be prevented by co-administration of some cholesterol lowering agents. Restoration of BBB dysfunction is clinically relevant, so the purpose of this study was to explore lipid-lowering agents could reverse BBB disturbances induced by chronic ingestion of SFA’s.

Methods

Wild-type mice were fed an SFA diet for 12 weeks to induce BBB dysfunction, and then randomised to receive atorvastatin, pravastatin or ibuprofen in combination with the SFA-rich diet for 2 or 8 weeks. Abundance of plasma-derived immunoglobulin-G (IgG) and amyloid-β enriched apolipoprotein (apo)-B lipoproteins within brain parenchyme were quantified utilising immunofluorescence microscopy.

Results

Atorvastatin treatment for 2 and 8 weeks restored BBB integrity, indicated by a substantial reduction of IgG and apo B, particularly within the hippocampus. Pravastatin, a water-soluble statin was less effective than atorvastatin (lipid-soluble). Statin effects were independent of changes in plasma lipid homeostasis. Ibuprofen, a lipid-soluble cyclooxygenase inhibitor attenuated cerebral accumulation of IgG and apo B as effectively as atorvastatin. Our findings are consistent with the drug effects being independent of plasma lipid homeostasis.

Conclusion

Our findings suggest that BBB dysfunction induced by chronic ingestion of SFA is reversible with timely introduction and sustained treatment with agents that suppress inflammation.
SR-BI associates with ABCG1 and inhibits ABCG1-mediated cholesterol efflux from cells to high-density lipoprotein 3
Authors: Song Guohua , Zong Chuanlong , Liu Qian , Si Yanhong , Liu Jie , Li Wei , Zhu Ping , Qin Shucun
Published: September 2012

Background

The single and combined effects of scavenger receptor-BI (SR-BI), ATP-binding cassette transporter (ABC) A1 and G1 on cholesterol efflux from Chinese Hamster Ovary (CHO) cells were investigated.

Results

When apolipoproteinA-I (apoA-I) was used as an acceptor, ABCA1 overexpression led to an increase in total cholesterol (TC) in medium which is attributable to a 2-fold increase in free cholesterol (FC) content. When high-density lipoprotein 3 (HDL3) was used as an acceptor, SR-BI overexpression not only promoted FC efflux, but also promoted the uptake of cholesteryl ester (CE) into cells, resulting in no TC varieties in medium. Overexpression of ABCG1 increased both the FC and CE levels in medium. However, when apoA-I and HDL3 were both used as acceptors, coexpression of SR-BI has no effect on ABCA1-mediated increased FC and TC accumulation in medium. Interestingly, coexpression of SR-BI with ABCG1 blocked the ABCG1-mediated cholesterol efflux to HDL3, mostly by promoting the reuptake of CE from the medium. Furthermore, co-immunoprecipitation experiments revealed that SR-BI interacted with ABCG1 in BHK cells overexpressing ABCG1 and SR-BI.

Conclusions

We found SR-BI associates with ABCG1 and inhibits ABCG1-mediated cholesterol efflux from cells to HDL3.
Phenolic-glycolipid-1 and lipoarabinomannan preferentially modulate TCR- and CD28-triggered proximal biochemical events, leading to T-cell unresponsiveness in mycobacterial diseases
Authors: Dagur Pradeep Kumar , Sharma Bhawna , Upadhyay Rajni , Dua Bhavyata , Rizvi Arshad , Khan Naim Akhtar , Katoch Vishwa Mohan , Sengupta Utpal , Joshi Beenu
Published: September 2012

Background

Advanced stages of leprosy show T cell unresponsiveness and lipids of mycobacterial origin are speculated to modulate immune responses in these patients. Present study elucidates the role of phenolicglycolipid (PGL-1) and Mannose-capped lipoarabinomannan (Man-LAM) on TCR- and TCR/CD28- mediated signalling.

Results

We observed that lipid antigens significantly inhibit proximal early signalling events like Zap-70 phosphorylation and calcium mobilization. Interestingly, these antigens preferentially curtailed TCR-triggered early downstream signalling events like p38 phosphorylation whereas potentiated that of Erk1/2. Further, at later stages inhibition of NFAT binding, IL-2 message, CD25 expression and T-cell blastogenesis by PGL-1 and Man-LAM was noted.

Conclusion

Altogether, we report that Man-LAM and PGL-1 preferentially interfere with TCR/CD28-triggered upstream cell signalling events, leading to reduced IL-2 secretion and T-cell blastogenesis which potentially could lead to immunosupression and thus, disease exacerbation, as noted in disease spectrum.
Alzheimer disease and platelets: how’s that relevant
Authors: Catricala Silvia , Torti Mauro , Ricevuti Giovanni
Published: September 2012

Alzheimer Disease (AD) is the most common neurodegenerative disorder worldwide, and account for 60% to 70% of all cases of progressive cognitive impairment in elderly patients. At the microscopic level distinctive features of AD are neurons and synapses degeneration, together with extensive amounts of senile plaques and neurofibrillars tangles. The degenerative process probably starts 20–30 years before the clinical onset of the disease. Senile plaques are composed of a central core of amyloid β peptide, Aβ, derived from the metabolism of the larger amyloid precursor protein, APP, which is expressed not only in the brain, but even in non neuronal tissues. More than 30 years ago, some studies reported that human platelets express APP and all the enzymatic activities necessary to process this protein through the same pathways described in the brain. Since then a large number of evidence has been accumulated to suggest that platelets may be a good peripheral model to study the metabolism of APP, and the pathophysiology of the onset of AD. In this review, we will summarize the current knowledge on the involvement of platelets in Alzheimer Disease. Although platelets are generally accepted as a suitable model for AD, the current scientific interest on this model is very high, because many concepts still remain debated and controversial. At the same time, however, these still unsolved divergences mirror a difficulty to establish constant parameters to better defined the role of platelets in AD.
Identification of BACE2 as an avid ß-amyloid-degrading protease
Authors: Abdul-Hay Samer O , Sahara Tomoko , McBride Melinda , Kang Dongcheul , Leissring Malcolm A
Published: September 2012

Background

Proteases that degrade the amyloid ß-protein (Aß) have emerged as key players in the etiology and potential treatment of Alzheimer’s disease (AD), but it is unlikely that all such proteases have been identified. To discover new Aß-degrading proteases (AßDPs), we conducted an unbiased, genome-scale, functional cDNA screen designed to identify proteases capable of lowering net Aß levels produced by cells, which were subsequently characterized for Aß-degrading activity using an array of downstream assays.

Results

The top hit emerging from the screen was ß-site amyloid precursor protein-cleaving enzyme 2 (BACE2), a rather unexpected finding given the well-established role of its close homolog, BACE1, in the production of Aß. BACE2 is known to be capable of lowering Aß levels via non-amyloidogenic processing of APP. However, in vitro, BACE2 was also found to be a particularly avid AßDP, with a catalytic efficiency exceeding all known AßDPs except insulin-degrading enzyme (IDE). BACE1 was also found to degrade Aß, albeit ~150-fold less efficiently than BACE2. Aß is cleaved by BACE2 at three peptide bonds—Phe19-Phe20, Phe20-Ala21, and Leu34-Met35—with the latter cleavage site being the initial and principal one. BACE2 overexpression in cultured cells was found to lower net Aß levels to a greater extent than multiple, well-established AßDPs, including neprilysin (NEP) and endothelin-converting enzyme-1 (ECE1), while showing comparable effectiveness to IDE.

Conclusions

This study identifies a new functional role for BACE2 as a potent AßDP. Based on its high catalytic efficiency, its ability to degrade Aß intracellularly, and other characteristics, BACE2 represents a particulary strong therapeutic candidate for the treatment or prevention of AD.
Morphological and immunohistochemical characterisation of seminomas in Norwegian dogs
Authors: Thorvaldsen Tor Espen , Nødtvedt Ane , Grotmol Tom , Gunnes Gjermund
Published: September 2012

Background

Seminomas in the dog have traditionally been assumed to resemble human spermatocytic seminomas, based on their low malignancy and high occurrence in old individuals. However, recently published studies indicate that canine seminomas can be classified as classical and spermatocytic seminomas in a similar way as in man, and that classical seminomas comprise a substantial proportion of seminomas in the dog. These two factors both contribute to increasing the potential of canine seminoma as a relevant model for human testicular cancer. The aim of the present study was to characterise seminoma in Norwegian dogs using morphology and immunohistochemistry, and determine whether these tumours are comparable with human classical seminoma.

Methods

By applying diagnostic criteria from human pathology, 45 seminomas from the Norwegian Canine Cancer Register were examined histologically with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) stains. All sections were stained immunohistochemically with antibodies against human placental alkaline phosphatase (PLAP) and the transmembrane receptor c-KIT.

Results

Although two of the seminomas showed immunohistochemical staining characteristics indicative of classical seminoma (PLAP+/c-KIT+), all 45 examined seminomas were morphologically consistent with spermatocytic seminoma.

Conclusions

The value of canine seminoma as a model for SE in man remains unclear. Among the 45 investigated tumours from Norwegian dogs, none were classified as classical seminoma based on morphological criteria consistent with human seminomas. Regional or breed differences in the occurrence of classical seminoma in the dog, as well as the lack of uniform diagnostic criteria, might explain the discrepancy between the findings in the current study and the results presented by other authors.
Seismic monitoring of radioactive waste repositories
Authors: Manukyan Edgar , Maurer Hansruedi , Marelli Stefano , Greenhalgh Stewart A. , Green Alan G.
Published: September 2012

Safe isolation of high-level radioactive waste (HLW) and spent nuclear fuel (SF) from the biosphere is an important concern for humanity. Many countries consider monitoring the evolving conditions of a HLW/SF repository over a long period noninvasively, in such a way as to not compromise the sealing of the repository. Remote active seismic methods are possible options. We performed extensive seismic measurements at the Mont Terri Rock Laboratory, located within a clay formation that is a potential host rock in the Swiss HLW/SF program. A scaled-down HLW/SF repository was simulated as a 13-m-long microtunnel of 1 m diameter. The dry sand-filled microtunnel was progressively water saturated and slightly overpressured. The monitoring system consisted of a pressure seismic source and a hydrophone cable located in two boreholes drilled perpendicular to the microtunnel and eight geophones equally distributed around the periphery of the microtunnel. Nonlinear anisotropic tomography of crosshole traveltimes allowed the gross velocity structure of the host rock to be determined, but due to the experiment geometry, the hydrophone traveltimes were inadequate for monitoring changes within the repository. In contrast, analysis of the geophone seismic traces enabled the saturation process to be characterized. An integrated interpretation of the geophone data in combination with extensive numerical modeling suggested that injection of the water resulted in significant self sealing of the microtunnel’s excavation damage/disturbed zone (EDZ) and substantial increases in the P-wave velocity of the microtunnel sand and EDZ. On the basis of our investigations, we concluded that seismic monitoring of a HLW/SF repository is feasible, as long as the sensors are installed as close to the repository as regulations allow.
Separation and imaging of seismic diffractions using migrated dip-angle gathers
Authors: Klokov Alexander , Fomel Sergey
Published: September 2012

Common-reflection angle migration can produce migrated gathers either in the scattering-angle domain or in the dip-angle domain. The latter reveals a clear distinction between reflection and diffraction events. We derived analytical expressions for events in the dip-angle domain and found that the shape difference can be used for reflection/diffraction separation. We defined reflection and diffraction models in the Radon space. The Radon transform allowed us to isolate diffractions from reflections and noise. The separation procedure can be performed after either time migration or depth migration. Synthetic and real data examples confirmed the validity of this technique.
Implementing a Systematic Approach to Meeting Patients' Cancer and Fertility Needs: A Review of the Fertile Hope Centers of Excellence Program
Authors: Reinecke Joyce D. , Kelvin Joanne F. , Arvey Sarah R. , Quinn Gwendolyn P. , Levine Jennifer , Beck Lindsay N. , Miller Andy
Published: September 2012

Widespread adoption of programs that incorporate the baseline elements identified in this study will not only comply with national guidelines but also address patients' reproductive needs and fundamentally affect future quality of life.
Identification and Correlates of Unmet Service Needs in Adult Leukemia and Lymphoma Survivors After Treatment
Authors: Parry Carla , Lomax Jana B. , Morningstar Elizabeth A. , Fairclough Diane L.
Published: September 2012

The authors' findings suggest directions for service provision and development of standards for quality care in adult leukemia and lymphoma survivors.
Human Capital Formation and Criminal Behavior: The Role of Early Childhood Education
Authors: Dos Santos Marcelo Rodrigues
Published: September 2012

This paper develops an overlapping generations model of criminal behavior, which extends prior research on crime by taking into account parental decisions about their children's education and about sending them to school when they become adolescents. Additionally, it is also assumed that acquired ability in childhood and school resources interplay to determine the student's probability of leaving school before graduation. Therefore, considering that dropping out of school and criminality are endogenously determined by the quality of early childhood education, school inputs and law enforcement parameters, this paper offers a framework to study the effects of interventions in early education on criminality and human capital accumulation vis-à-vis enhancing school resources and public spending on enforcement. Numerical simulations show that stimuli to increase investments in the education of children from disadvantaged families are much more cost-effective as a crime-prevention policy than expenditures on school resources and police protection.
On the K- and L-theory of hyperbolic and virtually finitely generated abelian groups
Authors: Lück Wolfgang , Rosenthal David
Published: September 2012

We investigate the algebraic K- and L-theory of the group ring
RG, where G is a hyperbolic or virtually finitely generated
abelian group and R is an associative ring with unit.
Characterization of angiotensin I-converting enzyme N-domain selectivity using positional-scanning combinatorial libraries of fluorescence resonance energy transfer peptides
Authors: Bersanetti Patrícia A. , Sabatini Regiane A. , Matos Beatriz S. , Douglas Ross G. , Nchinda Aloysius , Juliano Maria A. , Pesquero João Bosco , Sturrock Edward D. , Carmona Adriana K.
Published: September 2012

Somatic angiotensin I-converting enzyme (ACE) has two homologous active sites (N and C domains) that show differences in various biochemical properties. In a previous study, we described the use of positional-scanning synthetic combinatorial (PS-SC) libraries of fluorescence resonance energy transfer (FRET) peptides to define the ACE C-domain versus N-domain substrate specificity and developed selective substrates for the C-domain (Bersanetti et al., 2004). In the present work, we used the results from the PS-SC libraries to define the N-domain preferences and designed selective substrates for this domain. The peptide Abz-GDDVAK(Dnp)-OH presented the most favorable residues for N-domain selectivity in the P3 to P1′ positions. The fluorogenic analog Abz-DVAK(Dnp)-OH (Abz=ortho-aminobenzoic acid; Dnp=2,4-dinitrophenyl) showed the highest selectivity for ACE N-domain (k

cat

/K

m
=1.76 μm
-1·s-1). Systematic reduction of the peptide length resulted in a tripeptide that was preferentially hydrolyzed by the C-domain. The binding of Abz-DVAK(Dnp)-OH to the active site of ACE N-domain was examined using a combination of conformational analysis and molecular docking. Our results indicated that the binding energies for the N-domain-substrate complexes were lower than those for the C-domain-substrate, suggesting that the former complexes are more stable.
Genetic polymorphisms in the human tissue kallikrein (KLK) locus and their implication in various malignant and non-malignant diseases
Authors: Batra Jyotsna , O’Mara Tracy , Patnala Radhika , Lose Felicity , Clements Judith A.
Published: September 2012

The Kallikrein (KLK) gene locus encodes a family of serine proteases and is the largest contiguous cluster of protease-encoding genes attributed an evolutionary age of 330 million years. The KLK locus has been implicated as a high susceptibility risk loci in numerous cancer studies through the last decade. The KLK3 gene already has established clinical relevance as a biomarker in prostate cancer prognosis through its encoded protein, prostate-specific antigen. Data mined through genome-wide association studies (GWAS) and next-generation sequencing point to many important candidate single nucleotide polymorphisms (SNPs) in KLK3 and other KLK genes. SNPs in the KLK locus have been found to be associated with several diseases including cancer, hypertension, cardiovascular disease and atopic dermatitis. Moreover, introducing a model incorporating SNPs to improve the efficiency of prostate-specific antigen in detecting malignant states of prostate cancer has been recently suggested. Establishing the functional relevance of these newly-discovered SNPs, and their interactions with each other, through in silico investigations followed by experimental validation, can accelerate the discovery of diagnostic and prognostic biomarkers. In this review, we discuss the various genetic association studies on the KLK loci identified either through candidate gene association studies or at the GWAS and post-GWAS front to aid researchers in streamlining their search for the most significant, relevant and therapeutically promising candidate KLK gene and/or SNP for future investigations.
Cysteine cathepsins are not critical for TRAIL- and CD95-induced apoptosis in several human cancer cell lines
Authors: Špes Aleš , Sobotič Barbara , Turk Vito , Turk Boris
Published: September 2012

The potential role of cysteine cathepsins in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L)- and CD95 (Fas/APO-1)-induced apoptosis was investigated using four different cell lines (HeLa, HuH-7, Jurkat, and U-937). All four cell lines exhibited different levels of cathepsins and responded differently to apoptosis triggering, with Jurkat cells being the most sensitive and the only ones that were sensitive to the agonistic anti-APO-1 antibody. Apoptosis was accompanied by caspase activation, loss of the mitochondria and lysosome integrity, and the release of cysteine cathepsins into the cytosol, as judged based on the hydrolysis of the cysteine cathepsin substrate benzyloxycarbonyl-Phe-Arg-7-amino-4-methylcoumarin and by the immunological detection of cathepsin B. The inhibition of caspases by the broad-spectrum inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone prevented apoptosis, including the mitochondrial and lysosomal membrane permeabilization, as well as cathepsin release into the cytosol, consistent with caspases playing a crucial role in the process. Conversely, however, although the broad-spectrum cysteine cathepsin inhibitor (2S,3S)-trans-epoxysuccinyl-leucylamido-3-methyl-butane ethyl ester and the more cathepsin B-selective inhibitor [(2S,3S)-3-propylcarbamoyloxirane-2-carbonyl]-l-isoleucyl-l-proline methyl ester completely blocked cathepsin activity, these inhibitors neither prevented apoptosis and its progression nor the mitochondrial and lysosomal membrane permeabilization associated with this type of cell death. Consequently, cathepsin release into the cytosol was also not prevented. Together, these data indicate that cysteine cathepsins are not required for the TRAIL- and CD95-mediated apoptosis in various human cancer cell lines. This does not, however, rule out that lysosomes and cysteine cathepsins are involved in the amplification, but not in the initiation, of death receptor-mediated apoptosis in certain cell lines or under different stimulation conditions than the ones employed here.
β-Barrel scaffolds for the grafting of extracellular loops from G-protein-coupled receptors
Authors: Walser Reto , Kleinschmidt Jörg H. , Skerra Arne , Zerbe Oliver
Published: September 2012

Owing to the difficulties in production and purification of G-protein-coupled receptors (GPCRs), relatively little structural information is available about this class of receptors. Here we aim at developing small chimeric proteins, displaying the extracellular ligand-binding motifs of a human GPCR, the Y receptor. This allows the study of ligand-receptor interactions in simplified systems. We present comprehensive information on the use of transmembrane (OmpA) and soluble (Blc) β-barrel scaffolds. Whereas Blc appeared to be not fully compatible with our approach, owing to problems with refolding of the hybrid constructs, loop-grafted versions of OmpA delivered encouraging results. Previously, we described a chimeric construct based on OmpA displaying all three extracellular Y1 receptor loops in different topologies and showing moderate affinity to one of the natural ligands. Now, we present detailed data on the interaction of these constructs with several Y receptor ligands along with data on new constructs. Our findings suggest a common binding mode for all ligands, which is mediated through the C-terminal residues of the peptide ligand, supporting the functional validity of these hybrid receptors. The observed binding affinities, however, are well below those observed for the natural receptors, clearly indicating limitations in mimicking the natural systems.
The worldwide “wildfire” problem
Authors: Gill A. Malcolm , Stephens Scott L. , Cary Geoffrey J.
Published: September 2012

The worldwide “wildfire” problem is headlined by the loss of human lives and homes, but it applies generally to any adverse effects of unplanned fires, as events or regimes, on a wide range of environmental, social, and economic assets. The problem is complex and contingent, requiring continual attention to the changing circumstances of stakeholders, landscapes, and ecosystems; it occurs at a variety of temporal and spatial scales. Minimizing adverse outcomes involves controlling fires and fire regimes, increasing the resistance of assets to fires, locating or relocating assets away from the path of fires, and, as a probability of adverse impacts often remains, assisting recovery in the short term while promoting the adaptation of societies in the long term. There are short‐ and long‐term aspects to each aspect of minimization. Controlling fires and fire regimes may involve fire suppression and fuel treatments such as prescribed burning or non‐fire treatments but also addresses issues associated with unwanted fire starts like arson. Increasing the resistance of assets can mean addressing the design and construction materials of a house or the use of personal protective equipment. Locating or relocating assets can mean leaving an area about to be impacted by fire or choosing a suitable place to live; it can also mean the planning of land use. Assisting recovery and promoting adaptation can involve insuring assets and sharing responsibility for preparedness for an event. There is no single, simple, solution. Perverse outcomes can occur. The number of minimizing techniques used, and the breadth and depth of their application, depends on the geographic mix of asset types. Premises for policy consideration are presented.
Livestock‐Generated Nitrogen Exports from a Pastoral Wetland
Authors: McKergow Lucy A. , Rutherford J.C. , Timpany Graham C.
Published: September 2012

When wetlands are disturbed by cattle, pulses of contaminants may be released. We studied nitrogen exports from a small pastoral wetland (1725 m2) in the Lake Taupo Catchment, New Zealand, to which cattle and sheep had periodic access. Flow, turbidity, and water quality samples were collected at the wetland outlet over 2 yr. Turbidity was used to trigger sampling during livestock grazing and as a surrogate for organic N (OrgN) and total N (TN) in flux estimation. The wetland flowed throughout the study (median 0.285 L s−1) and was baseflow dominated (73%) but responded to rainfall (peak storm flow 166 L s−1). Organic N was the dominant N form exported (median OrgN:TN ratio 0.86). During cattle grazing periods, concentrations and fluxes of all forms of nitrogen at the outlet were elevated compared with storm and baseflow conditions during nongrazed periods. The TN fluxes were nine times greater when cattle grazed the wetland (306 g d−1) than under nongrazed baseflow conditions (32 g d−1). Cattle grazing occurred 9% of the time but accounted for 34% of TN export over 11 mo. Excluding cattle from small wetlands is likely to have immediate water quality benefits.
Field‐Scale Evaluation of Water Fluxes and Manure Solution Leaching in Feedlot Pen Soils
Authors: García Ana R. , Maisonnave Roberto , Massobrio Marcelo J. , Fabrizio de Iorio Alicia R.
Published: September 2012

Accumulation of beef cattle manure on feedlot pen surfaces generates large amounts of dissolved solutes that can be mobilized by water fluxes, affecting surface and groundwater quality. Our objective was to examine the long‐term impacts of a beef cattle feeding operation on water fluxes and manure leaching in feedlot pens located on sandy loam soils of the subhumid Sandy Pampa region in Argentina. Bulk density, gravimetric moisture content, and chloride concentration were quantified. Rain simulation trials were performed to estimate infiltration and runoff rates. Using chloride ion as a tracer, profile analysis techniques were applied to estimate the soil moisture flux and manure conservative chemical components leaching rates. An organic stratum was found over the surface of the pen soil, separated from the underlying soil by a highly compacted thin layer (the manure–soil interface). The soil beneath the organic layer showed greater bulk density in the A horizon than in the control soil and had greater moisture content. Greater concentrations of chloride were found as a consequence of the partial sealing of the manure–soil interface. Surface runoff was the dominant process in the feedlot pen soil, whereas infiltration was the main process in control soil. Soil moisture flux beneath pens decreased substantially after 15 yr of activity. The estimated minimum leaching rate of chloride was 13 times faster than the estimated soil moisture flux. This difference suggests that chloride ions are not exclusively transported by advective flow under our conditions but also by solute diffusion and preferential flow.
Soil Persistence and Fate of Carbamazepine, Lincomycin, Caffeine, and Ibuprofen from Wastewater Reuse
Authors: Williams C. F. , McLain J.E.T.
Published: September 2012

The reuse of treated wastewater for groundwater recharge is an effective way to provide advanced treatment and water storage. Contaminants such as human drugs have been identified as a potential problem for use of this water. Gilbert, Arizona maintains a 28.3‐ha facility designed to recharge 15,150 m3 d−1 through recharge basins constructed on native soil. The facility averages an infiltration rate of >5 cm d−1, resulting in the potential of pharmaceutical compounds leaching to groundwater. One 4‐ha basin was selected for spatial sampling of four pharmaceutically active compounds (PhACs). The compounds were carbamazepine, lincomycin, ibuprofen, and caffeine. Soils were extracted and analyzed using pressurized liquid extraction and liquid chromatography–mass spectrometry–mass spectrometry. The concentration of ibuprofen was below detection limits in all samples. Lincomycin exhibited no net accumulation from year to year but had significantly higher concentrations from depths of 0 to 5 cm than from depths >10 cm. Carbamazepine had the lowest concentration at 0 to 5 cm (0.18 ng g soil−1), providing evidence that there is potential degradation of carbamazepine in surface soils. Carbamazepine also exhibited significant accumulation from year to year. Caffeine exhibited net accumulation and had higher concentrations in surface samples. The accumulation of PhACs in the soil beneath recharge basins indicates that PhACs are being removed from the infiltrating water and that, regarding ibuprofen and lincomycin, the treatment is sustainable due to the lack of accumulation. Regarding carbamazepine and caffeine, further investigations are needed to determine possible management and environmental conditions that could prevent accumulation.
Effects on Carbon and Nitrogen Emissions due to Swine Manure Removal for Biofuel Production
Authors: Weaver Kim H. , Harper Lowry A. , Brown Sarah M.
Published: September 2012

Methane (CH4) and ammonia (NH3) are emitted from swine‐manure processing lagoons, contributing to global climate change and reducing air quality. Manure diverted to biofuel production is proposed as a means to reduce CH4 emissions. At a swine confined animal feeding operation in the U.S. Central Great Basin, animal manure was diverted from 12 farms to a biofuel facility and converted to methanol. Ammonia emissions were determined using the De Visscher Model from measured data of dissolved lagoon ammoniacal N concentrations, pH, temperature, and wind speed at the lagoon sites. Other lagoon gas emissions were measured with subsurface gas collection devices and gas chromatography analysis. During 2 yr of study, CO2 and CH4 emissions from the primary lagoons decreased 11 and 12%, respectfully, as a result of the biofuel process, compared with concurrently measured control lagoon emissions. Ammonia emissions increased 47% compared with control lagoons. The reduction of CH4 and increase in NH3 emissions agrees with a short‐term study measured at this location by Lagrangian inverse dispersion analysis. The increase in NH3 emissions was primarily due to an increase in lagoon solution pH attributable to decreased methanogenesis. Also observed due to biofuel production was a 20% decrease in conversion of total ammoniacal N to N2, a secondary process for the removal of N in anaerobic waste lagoons. The increase in NH3 emissions can be partially attributed to the decrease in N2 production by a proposed NH4+ conversion to N2 mechanism. This mechanism predicts that a decrease in NH4+ conversion to N2 increases ammoniacal N pH. Both effects increase NH3 emissions. It is unknown whether the decrease in NH4+ conversion to N2 is a direct or physical result of the decrease in methanogenesis. Procedures and practices intended to reduce emissions of one pollutant can have an unintended consequence on the emissions of another pollutant.
A New Method of Regional Eco‐environmental Quality Assessment and Its Application
Authors: Wang Xiaodan , Cao Yingzi , Zhong Xianghao , Gao Pan
Published: September 2012

Eco‐environmental quality assessment (EQA) is an intricate and challenging task that must take into account numerous natural, economic, political, and social factors, which are subject to multiple conflicting criteria. In this paper, a methodological reference framework is developed for EQA that combines the fuzzy Delphi method (FDM) and fuzzy analytical hierarchy process (FAHP) with a geographic information system (GIS). The proposed method significantly improves the accuracy and reliability of evaluation results through the incorporation of fuzzy set theory. A GIS not only has the ability to store and analyze large amounts of spatial data from different sources but also provides a consistent visualization environment for displaying the input data and the results of EQA. Furthermore, unlike prior EQAs, the proposed method can support the dynamic estimation of regional eco‐environmental quality by updating historical spatiotemporal data at little additional cost. A case study is presented for the western Tibetan Plateau. The study results show that worse, bad, and moderate eco‐environmental quality classes comprised 16.58, 20.15, and 24.84% of the total area, respectively. Good and better eco‐environmental quality classes accounted for 38.43%. This result indicates that nearly 62% of the total area is eco‐environmentally vulnerable. The results verified the usefulness and feasibility of the proposed method. The EQA can also help local managers make scientifically based and effective decisions about Tibetan eco‐environmental protection and land use.
Temporal and Spatial Patterns of Internal Phosphorus Recycling in a South Florida (USA) Stormwater Treatment Area
Authors: Dierberg Forrest E. , DeBusk Thomas A. , Henry Jaimee L. , Jackson Scott D. , Galloway Stacey , Gabriel Mark C.
Published: September 2012

Large constructed wetlands, known as stormwater treatment areas (STAs), have been deployed to remove phosphorus (P) in drainage waters before discharge into the Everglades in South Florida, USA. Their P removal performance depends on internal P cycling under typically hydrated, but with occasionally desiccated, conditions. We examined the spatial and temporal P removal capacity under different hydrologic conditions along a STA flow path. While inflow soils are P enriched, the outflow region of the wetland contained P‐unsaturated soils with minimal net recycling of bound soil P to the water column as plant‐available P. The outflow‐region soils were characterized by low porewater soluble reactive P (SRP) (≤40 μg L−1) and high total sulfide (TS) (2–9 mg L−1) concentrations, and total ammoniacal nitrogen (TAN) and SRP flux rates that averaged 1.51 and 0.002 mg m−2 d−1, respectively. Pronounced increases in porewater and surface‐water concentrations of SRP, dissolved organic P (DOP), and TAN were observed immediately after rehydration of the cell after an extended drought. Elevated total P concentrations persisted at the outfall of the cell for several months thereafter, resulting in an annual outflow total P concentration nearly threefold higher than the long‐term mean. Relative to processes that can occur during extended periods of inundation, such as sulfate‐enhanced P release from organic matter mineralization or iron sulfide formation, aerobic oxidation of organic matter during prolonged dryout periods is a more significant biogeochemical process in compromising soil P retention in STAs.
Relations between Retired Agricultural Land, Water Quality, and Aquatic‐Community Health, Minnesota River Basin
Authors: Christensen Victoria G. , Lee Kathy E. , McLees James M. , Niemela Scott L.
Published: September 2012

The relative importance of agricultural land retirement on water quality and aquatic‐community health was investigated in the Minnesota River Basin. Eighty‐two sites, with drainage areas ranging from 4.3 to 2200 km2, were examined for nutrient concentrations, measures of aquatic‐community health (e.g., fish index of biotic integrity [IBI] scores), and environmental factors (e.g., drainage area and amount of agricultural land retirement). The relation of proximity of agricultural land retirement to the stream was determined by calculating the land retirement percent in various riparian zones. Spearman's rho results indicated that IBI score was not correlated to the percentage of agricultural land retirement at the basin scale (p = 0.070); however, IBI score was correlated to retired land percentage in the 50‐ to 400‐m riparian zones surrounding the streams (p < 0.05), indicating that riparian agricultural land retirement may have more influence on aquatic‐community health than does agricultural land retirement in upland areas. Multivariate analysis of covariance and analysis of covariance models indicated that other environmental factors (such as drainage area and lacustrine and palustrine features) commonly were correlated to aquatic‐community health measures, as were in‐stream factors (standard deviation of water depth and substrate type). These results indicate that although agricultural land retirement is significantly related to fish communities as measured by the IBI scores, a combination of basin, riparian, and in‐stream factors act together to influence IBI scores.
Evaluation of a Closed Tunnel for Field‐Scale Measurements of Nitrous Oxide Fluxes from an Unfertilized Grassland Soil
Authors: Schäfer Klaus , Böttcher Jürgen , Weymann Daniel , von der Heide Carolin , Duijnisveld Wilhelmus H. M.
Published: September 2012

Emissions of the major greenhouse gas N2O from soils are characterized by huge spatial variability. An upscaling based on conventional small‐scale chamber measurements is thus questionable and may involve a considerable amount of uncertainty. In this feasibility study, we evaluated the applicability of a large, closed tunnel for field‐scale measurements of N2O fluxes from an unfertilized grassland soil. The tunnel, coupled to an open‐path Fourier transform infrared spectrometer, covered 500 m2. During a 2‐yr campaign, concurrent closed‐chamber measurements (area of 0.045 m2) were performed at the tunnel plot. The tunnel system enabled high‐density and precise N2O concentration measurements under dry, stable, nocturnal atmospheric conditions, but higher wind speeds and rain limited its application. To calculate an unbiased, predeployment N2O flux from the increase of N2O concentrations during tunnel deployment, we propose a novel approach based on inverse modeling (IMQ0). We show that IMQ0 is appropriate for the specific non–steady state tunnel setup. Compared with conventional models, which were developed for gas flux calculation from concentration gradients measured in vented closed chambers, IMQ0 is most accurate. Whereas N2O fluxes obtained from the tunnel measurements were generally small and at a typical background level, the chamber measurements revealed high spatial and temporal variability of N2O emissions, including slight N2O uptake and precipitation‐triggered emission peaks. The cumulative N2O fluxes of both methods differed by one order of magnitude and were smaller for the tunnel measurements. We argue that the chambers were occasionally susceptible to detection of hotspots and hot moments of N2O emission. However, these emissions were evidently not representative for the field scale. Compared with available greenhouse gas measurement techniques, we conclude that the tunnel may serve as a gap‐filling method between small‐scale chamber and ecosystem‐level micrometeorological techniques, particularly during stable nocturnal conditions.
Water Quality Effects of Herded Stream Crossings by Domestic Sheep Bands
Authors: Clark Patrick E. , Moffet Corey A. , Lewis Gregory S. , Seyfried Mark S. , Hardegree Stuart P. , Pierson Fredrick B.
Published: September 2012

Livestock impacts on total suspended solids (TSS) and pathogen (e.g., Escherichia coli) levels in rangeland streams are a serious concern worldwide. Herded stream crossings by domestic sheep (Ovis aries) are periodic, necessary managerial events on high‐elevation rangelands, but their impacts on stream water quality are largely unknown. We evaluated the effects of herded, one‐way crossings by sheep bands (about 2000 individuals) on TSS and E. coli concentration and load responses in downstream waters. Crossing trials were conducted during the summers of 2005 and 2006 on two reaches within each of three perennial streams in the Centennial Mountains of eastern Idaho and southwestern Montana. Water samples were collected at 2‐min intervals at an upstream background station and at stations 25, 100, 500, and 1500 m downstream just before and during each crossing trial. Crossings produced substantial increases in TSS and E. coli concentrations and loads downstream, but these concentration increases were localized and short lived. Maximum TSS concentration was highest 25 m downstream, declined as a function of downstream distance, and at 500 m downstream was similar to background. Post‐peak TSS concentrations at all downstream stations decreased to <25 mg L−1 within 24 to 48 min after reaching their maxima. Findings for E. coli concentration and load responses were similar to that of TSS but less clear cut. Stream‐crossing sheep do affect water quality; therefore, producers and resource managers should continue to evaluate the efficacy of herdsmanship techniques for reducing water quality impact.
Assessing the Quality of Freshwaters in a Protected Area within the Tagus River Basin District (Central Portugal)
Authors: Silva Emília , Pereira Ana Carina , Estalagem Soraia Patrícia , Moreira‐Santos Matilde , Ribeiro Rui , Cerejeira Maria José
Published: September 2012

Water‐sediment quality was assessed in an agricultural zone of a protected area within the Tagus River basin district (central Portugal) combining chemical analysis to 12 pesticide compounds and whole toxicity testing using the bacterium Vibrio fischeri, the algae Pseudokirchneriella subcapitata, the crustacean Daphnia magna, and the midge Chironomus riparius. The herbicides alachlor, atrazine ethofumesate, metolachlor, terbuthylazine, the insecticides chlorfenvinphos and chlorpyrifos, and the metabolite 3,4‐dichloroaniline were detected in surface water samples at four sites and in groundwater samples from six wells, during four sampling occasions. Measured concentrations were compared with parametric values for human consumption, groundwater quality standards, and environmental quality standards applicable to surface water established in European Union legislation. Most severe adverse effects were noted on the growth of P. subcapitata and lethality of D. magna in nondiluted water samples. Taking into account the values calculated by the method of toxic unit summation for pesticide mixtures, it was not possible to link the pesticides found to the toxicity detected in the water samples. Conducting this study with chemical analyses and biotests provided a more comprehensive quality assessment and realistic picture of the environmental samples analyzed, although additional studies are needed to evaluate the performance of mixture models for predicting mixture toxicity. This study underlines the importance of chemical analysis and whole toxicity testing as tools for assessing the impact of human activity on the status of water, mainly in protected zones.
Sulfur Turnover and Emissions during Storage of Cattle Slurry: Effects of Acidification and Sulfur Addition
Authors: Eriksen Jørgen , Andersen Astrid J. , Poulsen Henrik V. , Adamsen Anders Peter S. , Petersen Søren O.
Published: September 2012

Slurry acidification using sulfuric acid reduces ammonia emissions but also affects sulfur (S) cycling. Emission of sulfur is a source of malodor and reduces the sulfur fertilizer value of the slurry. We investigated the effect of sulfate and methionine amendments, alone or in combination with acidification, on sulfur transformations in slurry and emissions of volatile sulfur compounds (VSC) during storage of fresh and aged cattle slurry. When pH was lowered to 5.5 it resulted in an almost complete inhibition of sulfate reduction. There was a huge emission of hydrogen sulfide (H2S) with addition of sulfate and methionine (P< 0.01). Methanethiol (MT) was emitted in treatments with addition of methionine, especially when simultaneously acidified (P< 0.01). The large H2S production in the sulfate‐amended slurries resulted in little accumulation of MT and dimethyl sulfide (DMS) under neutral conditions, in contrast to acidic conditions where the degradation was inhibited and both MT and DMS accumulated. Based on odor activity values, untreated slurry had little odor development from S compounds, especially the aged slurry. Acidification did not significantly increase odor contribution from any of the compounds in fresh or aged slurry. Generally, addition of a sulfate increased the contribution from H2S dramatically, whereas acidification lowered the H2S contribution but increased that of MT. Thus, acidification of slurry with sulfuric acid may potentially produce more odor from S compounds than untreated slurry.
Phosphorus Flow and Characterization in Dry‐Grind Corn Ethanol Plants
Authors: Alkan‐Ozkaynak A. , Karthikeyan K. G.
Published: September 2012

Both the high phosphorus (P) content and P bioavailability of the animal feed coproducts of the corn‐ethanol industry could potentially contribute to increased manure and soil P levels and associated environmental issues (e.g., eutrophication). Therefore, a detailed modeling of total P mass flow to the coproducts (i.e., dry distillers grains with solubles, DDGS) was performed. Distribution of P between inorganic P and phytase‐hydrolyzable P forms was quantified for selected coproducts (thin stillage, DDGS, modified DDGS [mDDGS]). The P mass balance indicated that although corn is the major P contributor to the coproducts (80.2%), a substantial portion (19.4%) comes from yeast addition. Of the two components constituting DDGS, wet distillers grains and condensed solubles, the latter contributes to only one‐third of the mass but, importantly, yields 70.9% of P. The phytase enzyme used, Aspergillus ficuum, was very effective in hydrolyzing the nonorthophosphate P components of thin stillage, DDGS and mDDGS. Our results would help track P movement during various dry‐grind processing steps and formulate strategies for phytase enzyme supplementation to various postfermentation coproducts from corn‐ethanol plants.