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Biochar 2022年第1期4卷 635-651页

作者： Logan swaren salman safari Kurt O.Konhauser daniel s.Alessi Department of Earth and Atmospheric sciences University of Alberta3-16 Earth Sciences BuildingEdmontonAB T6G 2E3Canada

Nanoparticles are abundant in the subsurface,soil,streams,and water bodies,and are often a critical control on elemental speciation,transport and cycling in the natural *** review provides an overview of pyrolyzed biomass-derived nanoparticles(PBNPs),their surface properties and reactivity towards aqueous *** focus specifically on biochar-derived nanoparticles and activated carbon-derived nanoparticles which fall under our classification of *** carbon-iron(nano)composites are included in some instances where there are significant gaps in literature because of their environmental *** use of activated carbon,along with a resurgence in the manufacture and application of biochar for water treatment and soil amendment,has generated significant concerns about the mobility and toxicity of PBNPs derived from the bulk material in environmental *** examples are discussed to highlight current progress in understanding the influence of PBNPs on contaminant transport,followed by a critical discussion of gaps and future research directions.

关键词： Nanoparticles surface chemistry Activated carbon Biochar

screening primary racemic amines for enantioseparation by derivatized polysaccharide and cyclofructan columns

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Journal of Pharmaceutical Analysis 2016年第6期6卷 345-355页

作者： Yeeun Lim Zachary s.Breitbach daniel W.Armstrong Alain Berthod Department of Chemistry University of Texas at ArlingtonPlanetarium Place Institut des sciences Analytiques CNRSUniversité de Lyon

It is a challenge to separate the enantiomers of native chiral amines prone to deleterious silanol interactions. Aset of 39 underivatized chiral primary amines was screened for enantiomeric separation. seven recentlyintroduced commercial chiral columns were tested. They included six polysaccharide based chiral stationaryphases (CsP) with bonded derivatives, ChiralPak? IA, IB, IC, ID, IE and IF columns and a cyclofructanderivatized CsP, Larihc? CF6-P column. Both the normal phase (NP) mode with heptane/alcohol mobile phasesand the polar organic (PO) mode with acetonitrile/alcohol were evaluated. It was found that the cyclofructanbased CsP demonstrated the highest success rate in separating primary amines in the PO mode with only onechiral amine not resolved. It is shown that, when screening the columns, there is no standard optimal condition;an excellent mobile phase composition for one column may be poorly suited to another one. Althoughbutylamine was a good mobile phase additive for the polysaccharide columns in both PO and NP modes, it wasdetrimental to the enantio-recognition capability of the cyclofructan column. Triethylamine was the appropriatesilanol screening agent for this latter column.

关键词： Chiral primary amines Cyclofructan Bonded polysaccharide Enantiomeric separation

Watershed prioritization for conservation planning using RUsLE and morphometric methods,Northwestern Ethiopia

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山地科学学报(英文) 2023年第8期20卷 2242-2262页

作者： Agumassie Genet GELA daniel Ayalew MENGIsTU daniel Asfaw BEKELE Department of General Forestry Debre Markos UniversityBure 18Ethiopia Department of Geography and Environmental studies Bahir Dar UniversityBahir Dar 79Ethiopia Geo-spatial Data and Technology Center(GDTC) Bahir Dar UniversityBahir Dar 79Ethiopia

soil erosion and the subsequent sedimentation are serious environmental *** land management coupled with intense rainfall has complicated the problem in the Ethiopian ***,soil loss costs a profound amount of the national GDP and deters land *** soil loss and prioritizing areas for conservation is imperative for proper planning and resource ***,this study aimed at estimating the mean annual soil loss rate of Gilgel Abay watershed which has critical implications on Lake Tana and Abbay River(Upper Blue Nile River),using RUsLE and morphometric analysis *** including rainfall,soil,Digital Elevation Model and land use/land cover were used to generate important parameters required for the soil loss *** collected through field observation,consultation with experts and document analysis were used for validation *** results of the study reveal that the watershed experienced an average soil loss rate of 39.8 t ha^(-1)yr^(-1).subsequently,nearly 25%(37,038 ha)of the watershed is threatened by moderate to very severe soil *** the four sub watersheds,sub watershed 3(s3)and sub watershed 4(s4),which consist of about 65%(105,000 ha)of the total area of the study watershed,experienced an annual soil loss rate of over 30 t ha^(-1)yr^(-1).The amount of soil loss that the study watershed has experienced is above the soil loss tolerance level of Ethiopia(2-18 t ha^(-1)yr^(-1))and the tropical region(10 t ha^(-1)yr^(-1)).similarly,the results of morphometric analysis showed that the studied watershed has s-shaped hypsometric curve,an indication for maturity stage of landscape *** studied watershed is also characterized by a non-circular shaped drainage with rugged and dissected topography that contributes to high flash flood,peak discharge and incidence of soil *** result of both models signified that s3 and s4 are highly susceptible to soil ***,t

关键词： soil loss RUsLE model Morphometric analysis Gilgel Abay watershed

Using yttrium as an indicator to estimate total rare earth element concentration:a case study of anthracite-associated clays from northeastern Pennsylvania

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International Journal of Coal science & Technology 2020年第4期7卷 652-661页

作者： Xiaojing Yang daniel Kozar daniel Gorski Anthony Marchese James Pagnotti Rusty sutterlin Mohammad Rezaee Mark s.Klima sarma V.Pisupati John and Willie Leone Family Department of Energy and Mineral Engineering and the EMs Energy Institute Center for Critical MineralsThe Pennsylvania State University110 Hosier BuildingUniversity ParkPA 16802USA Texas Mineral Resources Corporation.539 El Paso st Sierra BlancaTX 79851USA Pagnotti Enterprises 46 Public SquareWilkes-BarrePA 18701USA Inventure Renewables Inc161625th Avenue.TuscaloosaAL 35401USA

This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and inexpensive *** than 10 anthracite-associated samples were collected from each of three Pennsylvanian sites(sites B,J and C)based on Thorium gamma ray logging suggesting high REY *** samples from each site were analyzed by ICP-Ms to determine the rare earth distribution patterns and to establish the site-specific linear equations of Y and *** Y contents of the remaining samples were measured by a portable X-ray fluorescence analyzer,and the REY values were estimated based on the site-specific linear equation developed earlier.R-squared values above 0.70 were obtained for all the estimation equations from all three sites on both a whole sample basis and an ash ***,ash content has been widely used as an indicator of high REY *** may not be applicable for a specific *** B in this study is an example where ash contents could not be statistically correlated with REY,so using Y for estimation is more *** demonstrated sample screening process is suitable for samples from sites that share more similar distribution patterns(either MREY or LREY or HREY)as well as for samples from sites that share multiple distribution patterns(LREY/MREY/HREY)depending on the desirable *** demonstrated process lowers the analytical cost from$70 to 80 dollars per sample to$10-15 per sample while significantly reducing the processing time and acid consumption for ICP *** is particularly true when a relatively large sample size is involved,for example,100 samples from one site analyzed by ICP-Ms/OEs.

关键词： Rare earth elements XRF analysis Correlations Prediction ICP analysis

supplemental smartamine M in higher-energy diets during the prepartal period improves hepatic biomarkers of health and oxidative status in Holstein cows

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Journal of Animal science and Biotechnology 2017年第3期8卷 624-635页

作者： Mario Vailati-Riboni Johan s.Osorio Erminio Trevisi daniel Luchini Juan J.Loor Mammalian Nutri Physio Genomics Department of Animal Sciences and Division of Nutritional SciencesUniversity of IllinoisUrbanaIL 61801USA Istituto di Zootecnica Facolt àdi scienze Agrarie Alimentari e AmbientaliUniversità Cattolica del Sacro Cuore29122 PiacenzaItaly Adisseo NA AlpharettaGA 30022USA. Dairy and Food science Department South Dakota State University1111 College Ave113H Alfred DairyScience HallBrookings SD 57007USA

Background： Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and oxidative stress in fresh cows. We tested the effectiveness of rumen-protected methionine in preventing the negative effect of feeding a higher-energy prepartum. Multiparous Holstein cows were fed a control lower-energy diet（CON, 1.24 Mcal/kg DM; high-straw） during the whole dry period（-50 d）, or were switched to a higher-energy（OVE, 1.54 Mcal/kg DM）, or OVE plus smartamine M（OVE ＋ sM; Adisseo NA） during the last 21 d before *** cows received the same lactation diet（1.75 Mcal/kg DM）. smartamine M was top-dressed on the OVE diet（0.07% of DM） from -21 through 30 d in milk（DIM）. Liver samples were obtained via percutaneous biopsy at -10, 7 and 21 DIM. Expression of genes associated with energy and lipid metabolism, hepatokines, methionine cycle, antioxidant capacity and inflammation was ***： Postpartal dry matter intake, milk yield, and energy-corrected milk were higher in CON and OVE ＋ sM compared with OVE. Furthermore, milk protein and fat percentages were greater in OVE ＋ sM compared with CON and OVE. Expression of the gluconeogenic gene PCK1 and the lipid-metabolism transcription regulator PPARA was again greater with CON and OVE ＋ sM compared with OVE. Expression of the lipoprotein synthesis enzyme MTTP was lower in OVE ＋ sM than CON or OVE. similarly, the hepatokine FGF21, which correlates with severity of negative energy balance, was increased postpartum only in OVE compared to the other two groups. These results indicate greater liver metabolism and functions to support a greater production in OVE ＋ sM. At 7 DIM, the enzyme GsR involved in the synthesis of glutathione tended to be upregulated in OVE than CON-fed cows, suggesting a greater antioxidant demand in overfed cows. Feeding OVE ＋ sM resulted in lower similar express

关键词： Energy Methionine Nutrigenomics Transition period

some Univalence Conditions for a General Integral Operator

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Chinese Annals of Mathematics,series B 2012年第6期33卷 801-806页

作者： Laura sTANCIU daniel BREAZ Department of Mathematics University of Pitesti Department of Mathematics University of Alba Iulia

The authors consider the classes of the univalent functions denoted by sH(β),sP and sP(α,β).On these classes,the univalence conditions for a general integral operator are studied.

关键词： Analytic function Integral operator Univalence condition Generalschwarz lemma

Comparing techniques for measuring corticosterone in tadpoles

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Current Zoology 2015年第5期61卷 835-845页

作者： Pablo BURRACO Rosa ARRIBAs saurabh s. KULKARNI daniel R. BUCHHOLZ Ivan GOMEZ-MEsTRE Department of Wetland Ecology Estacion Biologica de Dofiana (EBD-CSIC) C/Americo Vespucio s/n 41092 Sevilla Spain Department of Pediatrics Yale School of Medicine Yale University New Haven CT 0651 USA Department of Biological sciences University of Cincinnati Cincinnati OH 45221 USA

Glucocorticoids play a key role in mediating stress responses in vertebrates. Corticosterone （CORT） is the main glucocorticoid produced in amphibians, birds, and reptiles, and regulates several metabolic functions. The most common methods for quantifying CORT are competitive binding immunoassays： radioimmunoassay （RIA） and enzyme immunoassay （EIA）. RIA has been broadly used since the 1980＇s but it requires radioactivity. Commercial EIA kits permit quantifying hormone levels without radioactivity although the requirement for a larger sample volume may be a strong limitation for measurements involving larval amphibians. Here we used Xenopus laevis tadpoles to compare the performance of three commonly used procedures for determination of CORT： RIA on a chloroform extract of whole-body homogenate, EIA on plasma, and EIA on supematant of whole-body homogenate. We treated tadpoles with exogenous CORT at 0, 25, 50, and 100 nM. RIA could distinguish between 0 and 25 nM, and EIA on plasma between 0 and 50 nM, whereas whole-body homogenate EIA only detected significant differences between 0 and 100 riM. Each procedure presents advantages and disadvantages regarding sensitivity, the use of radioactivity, sample size, handling time, and economic cost. RIA is preferred when studying small-bodied animals from which blood samples cannot be obtained. When CORT level differences are intermediate and blood sampling is possible, EIA on plasma is a good non-radioactive alternative. EIA on whole-body homogenates may be useful to assess qualitative changes in CORT levels when considerable differences are expected. Finally, we discuss our findings in the context of previous studies on CORT in amphibians [Current Zoology 61 （5）： 835-845, 2015].

关键词： Corticosterone Radioimmunoassay Enzyme immunoassay Glucocorticoids Amphibians stress

Genetics of carotenoids for provitamin A biofortification in tropical-adapted maize

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The Crop Journal 2016年第4期4卷 313-322页

作者： Alhassan D.Halilu shehu G.Ado daniel A.Aba Inuwa s.Usman Department of Plant science Institute for Agricultural Research Ahmadu Bello University

Yellow maize contains high levels of β-carotene(βC), making it an important crop for combating vitamin A deficiency through biofortification. In this study, nine maize inbred lines were selected at random from 31 provitamin A(PVA) maize inbred lines and crossed in a partial diallel mating design to develop 36 crosses. The crosses were evaluated in the field in two locations(samaru and Kerawa) and their seed carotenoid content were determined by high-performance liquid chromatography. The modes of gene action, heritability, and correlations between agronomic traits and carotenoid content were estimated. Additive genetic variances(σ~2a) were lower than non-additive genetic variances(σ~2d) for all the carotenoids, plant height(PH), and grain yield(GY), suggesting a preponderance of non-additive gene action. Broad-sense heritability(H^2) was high(H^2> 60%) for zeaxanthin,days to anthesis, and PH, moderate(30% s a percentage of mean, considered with H^2, also suggests a preponderance of non-additive gene action for PVA carotenoids. Hybrid variety development is thus an appropriate approach to improving grain yield and PVA. GY showed no significant genotypic correlations with carotenoid content, suggesting that these traits can be improved concurrently. Thus, there is ample scope for improvement of PVA and GY in the sample of tropical-adapted maize.

关键词： Biofortification Tropical-adapted maize Provitamin A Carotenoids Gene actions Correlations

Response of brown anoles Anolis sagrei to multimodal signals from a native and novel predator

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Current Zoology 2012年第6期58卷 791-796页

作者： Omar L. ELMAsRI Marcus s. MORENO Courtney A. NEUMANN daniel T.BLUMsTEIN Department of Ecology and Evolutionary Biology University of California Los Angeles CA 90095-1606 USA

Abstract Multiple studies have focused on the importance of single modalities （visual, auditory, olfactory） in eliciting anti-predator behavior, however multiple channels are often engaged simultaneously. While examining responses to multiple cues can potentially reveal more complex behavioral responses, little is known about how multimodal processing evolves. By contrasting response to familiar and novel predators, insights can be gained into the evolution of multimodal responses. We studied brown anoles＇（Anolis sagrei） response to acoustic and visual predatory cues of a common potential predator, the great-tailed grackle Quiscalus mexicanus and to the American kestrel Falco sparverius, a species found in other populations but not present in our study population. We observed anole behavior before and after a stimulus and quantified rates of looking, display, and locomotion. Anoles increased their rate of locomotion in response to grackle models, an effect modulated by grackle vocalizations. No such response or modulation was seen when anoles were presented with kestrel stimuli. This suggests that the degree of sophistication of anole response to predators is experience dependent and that relaxed selection can result in reduced anti-predator response following loss of predators.

关键词： Anti-predator behavior Multimodal risk assessment Brown anoles