bluuebunny/crossref_metadata_2025 huggingface dataset:
Climate, people, fire and vegetation: new insights into vegetation dynamics in the Eastern Mediterranean since the 1st century AD
Authors: Bakker J. , Paulissen E. , Kaniewski D. , Poblome J. , De Laet V. , Verstraeten G. , Waelkens M.
Published: August 2012

Abstract. Anatolia forms a bridge between Europe, Africa and Asia and is influenced by all three continents in terms of climate, vegetation and human civilisation. Unfortunately, well dated palynological records focussing on the period from the end of the classical Roman period until subrecent times are rare for Anatolia and completely absent for southwest Turkey, resulting in a lacuna in knowledge concerning the interactions of climatic change, human impact, and environmental change in this important region. Two well dated palaeoecological records from the Western Taurus Mountains, Turkey, provide a first relatively detailed record of vegetation dynamics from late Roman times until the present in SW Turkey. Combining pollen, non-pollen palynomorphs, charcoal, sedimentological, archaeological data, and newly developed multivariate numerical analyses, allows for the disentangling of climatic and anthropogenic influences on vegetation change. Results show both the regional pollen signal as well as local soil sediment characteristics respond accurately to shifts in regional climatic conditions. Both climatic as well as anthropogenic change had a strong influence on vegetation dynamics and land use. A moist environmental trend during the late 3rd century caused an increase in marshes and wetlands in the moister valley floors, limiting possibilities for intensive crop cultivation at such locations. A mid 7th century shift to pastoralism coincided with a climatic deterioration as well as the start of Arab incursions into the region, the former driving the way in which the vegetation developed afterwards. Resurgence in agriculture was observed in the study during the mid 10th century AD, coinciding with the Medieval Climate Anomaly. An abrupt mid 12th century decrease in agriculture is linked to socio-political change, rather than the onset of the Little Ice Age. Similarly, gradual deforestation occurring from the 16th century onwards has been linked to changes in lands use during Ottoman times. The pollen data reveals that the old model of a fast rise in Pinus pollen after the end of the Beyşehir Occupation Phase is not necessarily accurate. The notion of high Pinus pollen percentages indicating an open landscape incapable of countering the influx of pine pollen is also deemed unrealistic. While multiple fires occurred in the region through time, they were never a major influence on vegetation dynamics and were mostly linked to increased abundance of pine forests, rather than the presence of human impact or of specifically wet or dry environmental conditions. While this study reveals much new information concerning the impact of climate change and human occupation on the environment, more studies from SW turkey are required in order to properly quantify the range of the observed phenomena and the magnitude of their impacts.
Skill and reliability of climate model ensembles at the Last Glacial Maximum and mid Holocene
Authors: Hargreaves J. C. , Annan J. D. , Ohgaito R. , Paul A. , Abe-Ouchi A.
Published: August 2012

Abstract. Paleoclimate simulations provide us with an opportunity to critically confront and evaluate the performance of climate models in simulating the response of the climate system to changes in radiative forcing and other boundary conditions. Hargreaves et al. (2011) analysed the reliability of the PMIP2 model ensemble with respect to the MARGO sea surface temperature data synthesis (MARGO Project Members, 2009) for the Last Glacial Maximum (LGM). Here we extend that work to include a new comprehensive collection of land surface data (Bartlein et al., 2011), and introduce a novel analysis of the predictive skill of the models. We include output from the PMIP3 experiments, from the two models for which suitable data are currently available. We also perform the same analyses for the PMIP2 mid-Holocene ensembles and available proxy data sets. Our results are predominantly positive for the LGM, suggesting that as well as the global mean change, the models can reproduce the observed pattern of change on the broadest scales, such as the overall land-sea contrast and polar amplification, although the more detailed regional scale patterns of change remains elusive. In contrast, our results for the mid-Holocene are substantially negative, with the models failing to reproduce the observed changes with any degree of skill. One likely cause of this problem may be that the globally- and annually-averaged forcing anomaly is very weak at the mid-Holocene, and so the results are dominated by the more localised regional patterns. The root cause of the model-data mismatch at regional scales is unclear. If the proxy calibration is itself reliable, then representation error in the data-model comparison, and missing climate feedbacks in the models are other possible sources of error.
Simulated European stalagmite record and its relation to a quasi-decadal climate mode
Authors: Lohmann G. , Wackerbarth A. , Langebroek P. , Werner M. , Fohlmeister J. , Scholz D. , Mangini A.
Published: August 2012

Abstract. A synthetic stalagmite record for the Bunker cave is constructed using a combined climate-stalagmite modeling approach. The power spectrum of the simulated speleothem calcite δ18O record has a pronounced peak at quasi-decadal time scale. Interestingly, mixing processes in the soil and karst above the cave represent a natural low-pass filter of the speleothem climate archive. We identify a quasi-decadal mode characterized by a "tripole pattern" of sea surface temperature affecting stalagmite δ18O values. This pattern, which is well-known in literature as the quasi-decadal mode in the North Atlantic, propagates eastwards and affects western European temperature surrounding the cave. Stalagmite δ18O values at Bunker Cave lag the regional surface temperature (r = 0.4) and soil moisture (r = −0.4) signal by 2–3 yr. Our modelling study suggests that stalagmite records from Bunker Cave are representative for large-scale teleconnections and can be used to obtain information about the North Atlantic and its decadal variability.
Quality assessment concept of the World Data Center for Climate and its application to CMIP5 data
Authors: Stockhause M. , Höck H. , Toussaint F. , Lautenschlager M.
Published: August 2012

Abstract. The preservation of data in a high state of quality which is suitable for interdisciplinary use is one of the most pressing and challenging current issues in long-term archiving. For high volume data such as climate model data, the data and data replica are no longer stored centrally but distributed over several local data repositories, e.g. the data of the Climate Model Intercomparison Project Phase 5 (CMIP5). The most important part of the data is to be archived, assigned a DOI, and published according to the World Data Center for Climate's (WDCC) application of the DataCite regulations. The integrated part of WDCC's data publication process, the data quality assessment, was adapted to the requirements of a federated data infrastructure. A concept of a distributed and federated quality assessment procedure was developed, in which the workload and responsibility for quality control is shared between the three primary CMIP5 data centers: Program for Climate Model Diagnosis and Intercomparison (PCMDI), British Atmospheric Data Centre (BADC), and WDCC. This distributed quality control concept, its pilot implementation for CMIP5, and first experiences are presented. The distributed quality control approach is capable of identifying data inconsistencies and to make quality results immediately available for data creators, data users and data infrastructure managers. Continuous publication of new data versions and slow data replication prevents the quality control from check completion. This together with ongoing developments of the data and metadata infrastructure requires adaptations in code and concept of the distributed quality control approach.
HESS Opinions "Biological catalysis of the hydrological cycle: life's thermodynamic function"
Authors: Michaelian K.
Published: August 2012

Abstract. Darwinian theory depicts life as being overwhelmingly consumed by a fight for survival in a hostile environment. However, from a thermodynamic perspective, life is a dynamic, out of equilibrium process, stabilizing and coevolving in concert with its abiotic environment. The living components of the biosphere on the Earth's surface of greatest biomass, the plants and cyanobacteria, are involved in the transpiration of a vast amount of water. Transpiration is part of the global water cycle, and it is this cycle that distinguishes Earth from its apparently life-barren neighboring planets, Venus and Mars. The dissipation of sunlight into heat by organic molecules in the biosphere, and its coupling to the water cycle (as well as other abiotic processes), is by far the greatest entropy-producing process occurring on Earth. Life, from this perspective, can be viewed as performing an important thermodynamic function, acting as a dynamic catalyst by aiding irreversible abiotic processes such as the water cycle, hurricanes, and ocean and wind currents to produce entropy. The role of animals in this view is that of unwitting but dedicated servants of the plants and cyanobacteria, helping them to grow, and to spread into initially inhospitable areas.
Threshold values and management options for nutrients in a catchment of a temperate estuary with poor ecological status
Authors: Hinsby K. , Markager S. , Kronvang B. , Windolf J. , Sonnenborg T. O. , Thorling L.
Published: August 2012

Abstract. Intensive farming has severe impacts on the chemical status of groundwater and streams and consequently on the ecological status of dependent ecosystems. Eutrophication is a widespread problem in lakes and marine waters. Common problems are hypoxia, algal blooms, fish kills, and loss of water clarity, underwater vegetation, biodiversity and recreational value. In this paper we evaluate the nitrogen (N) and phosphorus (P) concentrations of groundwater and surface water in a coastal catchment, the loadings and sources of N and P, and their effect on the ecological status of an estuary. We calculate the necessary reductions in N and P loadings to the estuary for obtaining a good ecological status, which we define based on the number of days with N and P limitation, and the corresponding stream and groundwater threshold values assuming two different management options. The calculations are performed by the combined use of empirical models and a physically based 3-D integrated hydrological model of the whole catchment. The assessment of the ecological status indicates that the N and P loads to the investigated estuary should be reduced to levels corresponding to 52 and 56% of the current loads, respectively, to restore good ecological status. Model estimates show that threshold total N (TN) concentrations should be in the range of 2.9 to 3.1 mg l−1 in inlet freshwater (streams) to Horsens estuary and 6.0 to 9.3 mg l−1 in shallow aerobic groundwater (∼ 27–41 mg l−1 of nitrate), depending on the management measures implemented in the catchment. The situation for total P (TP) is more complex, but data indicate that groundwater threshold values are not needed. The stream threshold value for TP to Horsens estuary for the selected management options is 0.084 mg l−1. Regional climate models project increasing winter precipitation and runoff in the investigated region resulting in increasing runoff and nutrient loads to the Horsens estuary and many other coastal waters if present land use and farming practices continue. Hence, lower threshold values are required in many coastal catchments in the future to ensure good status of water bodies and ecosystems.
Quantitative analysis on the environmental impact of large-scale water transfer project on water resource area in a changing environment
Authors: Yan D. H. , Wang H. , Li H. H. , Wang G. , Qin T. L. , Wang D. Y. , Wang L. H.
Published: August 2012

Abstract. The interbasin long-distance water transfer project is key support for the reasonable allocation of water resources in a large-scale area, which can optimize the spatio-temporal change of water resources to secure the amount of water available. Large-scale water transfer projects have a deep influence on ecosystems; besides, global climate change causes uncertainty and additive effect of the environmental impact of water transfer projects. Therefore, how to assess the ecological and environmental impact of megaprojects in both construction and operation phases has triggered a lot of attention. The water-output area of the western route of China's South-North Water Transfer Project was taken as the study area of the present article. According to relevant evaluation principles and on the basis of background analysis, we identified the influencing factors and established the diagnostic index system. The climate-hydrology-ecology coupled simulation model was used to simulate and predict ecological and environmental responses of the water resource area in a changing environment. The emphasis of impact evaluation was placed on the reservoir construction and operation scheduling, representative river corridors and wetlands, natural reserves and the water environment below the dam sites. In the end, an overall evaluation of the comprehensive influence of the project was conducted. The research results were as follows: the environmental impacts of the western route project in the water resource area were concentrated on two aspects: the permanent destruction of vegetation during the phase of dam construction and river impoundment, and the significant influence on the hydrological situation of natural river corridor after the implementation of water extraction. The impact on local climate, vegetation ecology, typical wetlands, natural reserves and the water environment of river basins below the dam sites was small.
Regional climate models downscaling in the Alpine area with Multimodel SuperEnsemble
Authors: Cane D. , Barbarino S. , Renier L. A. , Ronchi C.
Published: August 2012

Abstract. The climatic scenarios show a strong signal of warming in the Alpine area already for the mid XXI century. The climate simulations, however, even when obtained with Regional Climate Models (RCMs), are affected by strong errors where compared with observations, due to their difficulties in representing the complex orography of the Alps and limitations in their physical parametrization. Therefore the aim of this work is reducing these model biases using a specific post processing statistic technique to obtain a more suitable projection of climate change scenarios in the Alpine area. For our purposes we use a selection of RCMs runs from the ENSEMBLES project, carefully chosen in order to maximise the variety of leading Global Climate Models and of the RCMs themselves, calculated on the SRES scenario A1B. The reference observation for the Greater Alpine Area are extracted from the European dataset E-OBS produced by the project ENSEMBLES with an available resolution of 25 km. For the study area of Piedmont daily temperature and precipitation observations (1957–present) were carefully gridded on a 14-km grid over Piedmont Region with an Optimal Interpolation technique. Hence, we applied the Multimodel SuperEnsemble technique to temperature fields, reducing the high biases of RCMs temperature field compared to observations in the control period. We propose also the first application to RCMS of a brand new probabilistic Multimodel SuperEnsemble Dressing technique to estimate precipitation fields, already applied successfully to weather forecast models, with careful description of precipitation Probability Density Functions conditioned to the model outputs. This technique reduces the strong precipitation overestimation by RCMs over the alpine chain and reproduces well the monthly behaviour of precipitation in the control period.
Snow glacier melt estimation in tropical Andean glaciers using Artificial Neural Networks
Authors: Moya Quiroga V. , Mano A. , Asaoka Y. , Udo K.
Published: August 2012

Abstract. Snow and glacier melt (SGM) estimation plays an important role in water resources management. Although melting process can be modelled by energy balance methods, such studies require detailed data which is rarely available. Hence, new and simpler approaches are needed for SGM estimations. Artificial Neural Networks (ANN) is a modelling paradigm able to reproduce complex non-linear processes without the need of an explicit representation. The present study aims at developing an ANN based technique for estimating SGM rates using available and easy to obtain data such as Temperature and short wave radiation. Several ANN models were developed to represent the SGM process of a tropical glacier in the Bolivian Andes. The main data consisted on short wave radiation and temperature. It was found that accuracy may be increased by considering relative humidity and melting from previous time steps. The model represents the daily pattern showing variation of the melting rates throughout the day, with highest rate at noon. The melting rate in October (1.35 mm h−1) is nearly three times higher than July's melting rate (0.50 mm h−1). Results indicate that the exposure time to melting in October is 12 h, while in July is 9 h. This new methodology allows estimation of SGM at different hours throughout the day, reflecting its daily variation which is very important for tropical glaciers where the daily variation is greater than the yearly one. This methodology will provide useful data for better understanding the glacier retreat process and for analysing future water scenarios.
Continuous multi-criteria methods for crop and soil conservation planning on La Colacha (Río Cuarto, Province of Córdoba, Argentina)
Authors: Antón J. M. , Grau J. B. , Cisneros J. M. , Laguna F. V. , Aguado P. L. , Cantero J. J. , Andina D. , Sánchez E.
Published: August 2012

Abstract. Agro-areas of Arroyos Menores (La Colacha) west and south of Río Cuarto (Prov. of Córdoba, Argentina) basins are very fertile but have high soil loses. Extreme rain events, inundations and other severe erosions forming gullies demand urgently actions in this area to avoid soil degradation and erosion supporting good levels of agro production. The authors first improved hydrologic data on La Colacha, evaluated the systems of soil uses and actions that could be recommended considering the relevant aspects of the study area and applied decision support systems (DSS) with mathematic tools for planning of defences and uses of soils in these areas. These were conducted here using multi-criteria models, in multi-criteria decision making (MCDM); first of discrete MCDM to chose among global types of use of soils, and then of continuous MCDM to evaluate and optimize combined actions, including repartition of soil use and the necessary levels of works for soil conservation and for hydraulic management to conserve against erosion these basins. Relatively global solutions for La Colacha area have been defined and were optimised by Linear Programming in Goal Programming forms that are presented as Weighted or Lexicographic Goal Programming and as Compromise Programming. The decision methods used are described, indicating algorithms used, and examples for some representative scenarios on La Colacha area are given.
El mercado laboral de los titulados en Biblioteconomía y Documentación: análisis de las ofertas de empleo publicadas en IWETEL durante el periodo 2000-2007
Authors: Artaza Carlos Hugo
Published: August 2012

Con la finalidad de describir las características que presentan las ofertas laborales destinadas a titulados en Biblioteconomía y Documentación en España se analizaron los ofrecimientos publicados en la lista de interés IWETEL durante el periodo 2000-2007. Con las ofertas se efectuaron análisis estadísticos referidos a: número de empleos ofertados, tipología de las organizaciones demandantes, requisitos solicitados y modalidad de los contratos. Se concluye que la mayor demanda de empleos proviene de organizaciones empresariales. Las organizaciones demandantes son mayormente del ámbito privado y el tipo de contrato ofrecido de carácter temporario. En relación a lo conocimientos requeridos, las áreas de Tecnología de la Información, Organización y Tratamiento de la Información e Idiomas figuran entre los más demandados por los empleadores.
To Dwell for the Postcolonial
Authors: Farred Grant
Published: August 2012

None
Claire Pagès, Lyotard et l’aliénation
Authors: McLennan Matthew R.
Published: August 2012

Review of Claire Pagès, Lyotard et l'aliénation
Forest/Habitat Fragmentation and Human-elephant Conflicts in the Takamanda-Mone Landscape of the South West Region of Cameroon
Authors: Fuashi Nkwatoh Athanasius , Fosah Victor Chik
Published: August 2012

Forest/habitat fragmentation and Human-elephant conflicts are among the key factors that are of great concern to conservationists as far as achieving the goals of elephant conservation within their range states is concerned. Although much has been done in some protected areas in the Central African Sub-Region in general and in Cameroon in particular on forest/habitat fragmentation and human-elephant conflicts, very little is known of this situation in the Takamanda-Mone Landscape of South West Cameroon. The absence of such a valuable baseline data has created a knowledge gap that need to be closed and at the same time provides the management bench of the Landscape with appropriate tools for decision making. In the light of the above, there is therefore the need to source baseline information with respect to forest/habitat fragmentation and human-elephant conflicts in the Takamanda National Park and Mone Forest Reserve. It is from this back drop, that this study ‘on the evaluation of forest/habitat fragmentation and Human-elephant conflicts in the Takamanda-Mone Landscape of the South West Region of Cameroon was initiated as a contribution to the ongoing regional search for baseline information on the forest/habitat fragmentation and human elephant conflicts in Cameroon. The study in order to achieve set objectives employed socio-economic and Biological assessment techniques. Biological assessment took the form of line transect establishment, a hunter guided survey, the use of the Global Positioning Systems (GPS Garmin 60CSx) and the Geographic Information System (GIS). The socio-economic techniques made use of the random and the purposive sampling methodologies for the selection of villages and the respondents for questionnaire administration. Alongside these sampling techniques, some selected Participatory Rural Appraisal (PRA) tools were used for data collection. Results revealed that forest/habitat fragmentation and human-elephant conflicts are very prominent in the Takamanda-Mone Landscape due to human activities that are carried out in the area. These activities were identified to range from farming, hunting, poaching, local timber exploitation, Non-timber Forest Products (NTFPs) gathering, road construction to settlement. The associated conflicts (both direct and indirect) were identified to span from crop destruction to loss of lives and injuries. The locations and the effective carry out of these activities were found to have fragmented forest/ habitats and these has resulted in the decline of elephant populations in the study area. In order to reverse the present trend of events, the Takamanda-Mone landscape should be upgraded and classified into a National Park.
HIV/AIDS Dynamics with Three Control Strategies: The Role of Incidence Function
Authors: Kateme Emmanuelina L. , Tchuenche Jean M. , Hove-Musekwa Senelani D.
Published: August 2012

The type of incidence function used in epidemiological models is generally a matter of choice and convenience. Basic deterministic HIV/AIDS models with standard and saturated incidences are developed and extended to include three control measures, namely, public health educational campaigns, condom use, and treatment. The potential impact of these incidence functions on long-term projection of the disease dynamics is theoretically assessed, both qualitatively and quantitatively. Conditions for the stability of the model steady states are provided. The model with saturated incidence yields a higher number of secondary infections compared to the same outcome in the standard incidence formulation.
A Liquid Chromatography Method for Determination of Selected Amino Acids, Coenzymes, Growth Regulators, and Vitamins from Cicer arietinum (L.) and Solanum lycopersicum (L.)
Authors: Meher Hari Charan , Gajbhiye Vijay T , Singh Ghanendra
Published: August 2012

A bottleneck in crosstalk and QC research has been the quantification of diverse chemotypes in small amounts of tissue. An LC-UV method for estimating 28 selected metabolites of the regulatory network underlying growth, development, maintenance, vital functions, defense reactions, and food quality is reported. The method was based on binary gradient resolutions of the analytes in an RP C18 column. The mobile phase comprised solvent A [water + 0.1% trifluoroacetic acid (TFA)] and B (acetonitrile + 0.085% TFA at a flow rate of 1 mL/min. Twenty-three metabolites (selected amino acids, coenzymes, growth regulators, phenolic antioxidant, and water-soluble vitamins) were detected at 254 nm, and four fat-soluble vitamins at 280 nm. Jasmonic acid was quantified at 210 nm. The RSDs of peak area and retention time for each metabolite were <5.8%. The calibration graphs were linear with R2 values ranging from 0.98 to 0.99. The LODs (μg/mL) were about 0.01–1.0 for 23 metabolites quantified at 254 nm, 0.1–0.2 for fat-soluble vitamins, and 0.1 for jasmonic acid. The recoveries ranged from 80 to 105%, with RSDs of 2.8 to 11.2%. The method has been satisfactorily applied for determination of 28 metabolites from Cicer arietinum (L.) and Solanum lycopersicum (L.). It could be an alternative and competitive method of choice that can cheaply and easily perform routine analysis for food quality and targeted metabolomics of chickpea and tomato in response to stressors.
Quantitation of Transdermal Tadalafil in Human Skin by Reversed-Phase High-Performance Liquid Chromatography
Authors: Mehanna Mohammed H , Motawaa Abdel M , Samaha Magda W
Published: August 2012

A reliable and sensitive HPLC method was developed for the quantitation of tadalafil transdermal permeation through human skin. An RP column with UV detection at 290 nm was used for chromatographic separation at ambient temperature. The mobile phase was acetonitrile–water containing 20 mM pH 7 phosphate buffer (35/65, v/v) with a flow rate of 1.0 mL/min. The LOQ achieved was 1 ng/mL, and the calibration curve showed good linearity over the concentration range of 5–2000 ng/mL for tadalafil, with a determination coefficient (R2) of 0.998. The RSD values of intraday and interday analyses were all within 7%. Parameters of validation proved the precision of the method; this validated method was applied for the determination of tadalafil in transdermal permeation and drug deposition in human skin studies.
Development and Validation of a Liquid Chromatographic/Tandem Mass Spectrometric Method for Determination of Chlortetracycline, Oxytetracycline, Tetracycline, and Doxycycline in Animal Feeds
Authors: Guo Liang , Chen Yiqiang , Zhang Liying , Yang Wenjun , He Pingli
Published: August 2012

A selective and accurate LC/MS/MS method for the simultaneous determination of chlortetracycline (CTC), oxytetracycline (OTC), tetracycline (TC), and doxycycline (DC) in animal feeds was developed. Samples were extracted with Na2EDTA-McIlvaine buffer and further purified with Oasis HLB SPE columns. The purified extract was separated on an Xbridge C18 column and detected by LC/MS/MS with positive electrospray ionization in the multiple reaction monitoring mode. This method provided average recoveries of 80.9 to 119.5%, with CVs of 1.7 to 9.8% in the range of 0.5 to 50 mg/kg CTC, OTC, TC, and DC in feeds, except the average recovery of CTC was 76.0%, with a CV of 14.6% in pig feed spiked with 0.5 mg/kg CTC. The linear ranges for the four TCs determined by LC/MS/MS ranged from 0.005 to 2.5 μg/mL with a linear correlation coefficient (R2) >0.99. The LOD and LOQ for CTC, OTC, TC, and DC in pig and poultry feeds ranged from 0.003 to 0.02 and 0.01 to 0.05 μg/g, respectively. The method was successfully applied for the analysis of 30 real feed samples, and no illegal use was detected.
A Method for the Routine Determination of Methylmercury in Marine Tissue by GC Isotope Dilution-ICP-MS
Authors: Valdersnes Stig , Maage Amund , Fliegel Daniel , Julshamn Kåre
Published: August 2012

Currently, there is no legal limit for methyl mercury (MeHg) in food; thus, no standardized method for the determination of MeHg in seafood exists within the European jurisdiction. In anticipation of a future legislative limit an inductively coupled plasma isotope dilution mass spectrometry (GC-ICP-ID-MS) method was developed in collaboration with the European Standardization Organization (CEN). The method comprises spiking the tissue sample with Me201Hg, followed by decomposition with tetramethylammonium hydroxide, pH adjustment and derivatization with sodium tetraethylborate, and finally organic extraction of the derivatized MeHg in a hexane phase. Subsequently, the sample is analyzed via GC-ICP-MS and the result calculated using the ID equation. The working range of the method was 0.0005–1.321 mg/kg MeHg in marine tissue, with an internal reproducibility (RSD) of 12–1%. The method was validated based on statistical measures, such as the z-scores, using the commercially available reference materials from National Institute of Standards and Technology Standard Reference Material (NIST SRM) 1566b, NIST SRM 2977 and National Research Council of Canada (NRCC) TORT 2, NRCC, DORM 3, NRCC DOLT 4, and European Reference Material (ERM) CE 464. Z-scores for all standard reference materials, except for NIST SRM 1566b, were better than |1.5|. The wide range of marine tissues used during the validation ensures that the method will be applicable for measuring of MeHg in seafood matrixes of all kinds.
High-Performance Liquid Chromatography Quantification of Principal Antioxidants in Black seed (Nigella sativa L.) Phytopharmaceuticals
Authors: Hadad Ghada M , Abdel Salam Randa A , Soliman Rabab M , Mesbah Mostafa K
Published: August 2012

A new, simple, sensitive, rapid, and accurate isocratic RP-HPLC method was developed and validated for simultaneous analysis of the principal antioxidants of Nigella sativa, i.e., thymoquinone (TQ), carvacrol (CR), and its isomer thymol (THY), in different phytopharmaceuticals. The mobile phase was water–methanol (40 + 60, v/v) at a flow rate of 1.5 mL/min. Quantification was achieved with UV detection at 254 nm, based on peak area. The method was validated for linearity, accuracy, precision, selectivity, and robustness. The proposed method is stability-indicating for determination of TQ in the presence of its degradants. The LOD and LOQ (μg/mL) were, respectively, 0.006 and 0.021 for TQ, 0.002 and 0.006 for CR, and 0.027 and 0.090 for THY. The mean recoveries measured at three concentrations were higher than 99%, with RSD <2%. This analytical method is suitable for quality control of the marker substances in this widely used natural protective and curative remedy.
Validation Study of the BetaStar® Plus Lateral Flow Assay for Detection of Beta-Lactam Antibiotics in Milk
Authors: Abouzied Mohamed , Driksna Dana , Walsh Coilin , Sarzynski Michael , Walsh Aaron , Ankrapp David , Klein Frank , Rice Jennifer , Mozola Mark
Published: August 2012

A validation study designed to meet the requirements of the AOAC Research Institute and the U.S. Food and Drug Administration, Center for Veterinary Medicine (FDA/CVM) was conducted for a receptor and antibody-based, immunochromatographic method (BetaStar® Plus) for detection of beta-lactam antibiotic residues in raw, commingled bovine milk. The assay was found to detect amoxicillin, ampicillin, ceftiofur, cephapirin, cloxacillin, and penicillin G at levels below the FDA tolerance/safe levels, but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments (NCIMS). Results of the Part I (internal) and Part II (independent laboratory) dose-response studies employing spiked samples were in close agreement. The test was able to detect all six drugs at the approximate 90/95% sensitivity levels when presented as incurred residues in milk collected from cows that had been treated with the specific drug. Selectivity of the assay was 100%, as no false-positive results were obtained in testing of 1031 control milk samples. Results of ruggedness experiments established the operating parameter tolerances for the BetaStar Plus assay. Results of cross-reactivity testing established that the assay detects certain other beta-lactam drugs (dicloxacillin and ticarcillin), but it does not cross-react with any of 30 drugs belonging to other classes. Abnormally high bacterial or somatic cell counts in raw milk produced no interference with the ability of the test to detect beta-lactams at tolerance/safe levels.
DNA Barcode Identification of Black Cohosh Herbal Dietary Supplements
Authors: Baker David A , Stevenson Dennis Wm , LittLe Damon P
Published: August 2012

Black cohosh (Actaea racemosa) herbal dietary supplements are commonly consumed to treat menopausal symptoms, but there are reports of adverse events and toxicities associated with their use. Accidental misidentification and/or deliberate adulteration results in harvesting other related species that are then marketed as black cohosh. Some of these species are known to be toxic to humans. We have identified two matK nucleotides that consistently distinguish black cohosh from related species. Using these nucleotides, an assay was able to correctly identify all of the black cohosh samples in the validation set. None of the other Actaea species in the validation set were falsely identified as black cohosh. Of 36 dietary supplements sequenced, 27 (75%) had a sequence that exactly matched black cohosh. The remaining nine samples (25%) had a sequence identical to that of three Asian Actaea species (A. cimicifuga, A. dahurica, and A. simplex). Manufacturers should routinely test plant material using a reliable assay to ensure accurate labeling.
Development of Dipsticks for Simultaneous Detection of Vip3A and Cry1Ab/Cry1Ac Transgenic Proteins
Authors: Kumar Rajesh
Published: August 2012

The number of genetically modified (GM) crops being cultivated and its produce reaching market is increasing every year. The transgenes (vip3A, cry1Ab, and cry1Ac) from Bacillus thuringiensis are being used by plant breeders, apart from other transgenes for developing insect pest-resistant GM crops. It is therefore necessary to develop an easy, rapid, and reliable detection assay to discriminate GM crops and non-GM crops. Dipstick strips using colloidal gold-labeled polyclonal antibodies were developed for simultaneous detection of Vip3A and Cry1Ab/Cry1Ac proteins. The assay was essentially based on the sandwich format of immunoassay, which was completed within 10 min, and the results were evaluated visually. The detection limits were 50 ng/mL (50 ppb) for both Cry1Ac and Cry1Ab proteins, and 100 ng/mL (100 ppb) for Vip3A protein. The developed dipsticks are suitable for on-site simultaneous screening of GM crops bearing two proteins, which, in turn, reduce cost and time of the assay.
Determination of Trigonelline, Nicotinic Acid, and Caffeine in Yunnan Arabica Coffee by Microwave-Assisted Extraction and HPLC with Two Columns in Series
Authors: Liu Hongcheng , Shao Jinliang , Li Qiwan , Li Yangang , Yan Hong Mei , He Lizhong
Published: August 2012

A simple, rapid method was developed for simultaneous extraction of trigonelline, nicotinic acid, and caffeine from coffee, and separation by two chromatographic columns in series. The trigonelline, nicotinic acid, and caffeine were extracted with microwave-assisted extraction (MAE). The optimal conditions selected were 3 min, 200 psi, and 120°C. The chromatographic separation was performed with two columns in series, polyaromatic hydrocarbon C18 (250 × 4.6 mm id, 5 μm particle size) and Bondapak NH2 (300 × 3.9 mm id, 5 μm particle size). Isocratic elution was with 0.02 M phosphoric acid–methanol (70 + 30, v/v) mobile phase at a flow rate of 0.8 mL/min. Good recoveries and RSD values were found for all analytes in the matrix. The LOD of the three compounds was 0.02 mg/L, and the LOQ was 0.005% in the matrix. The concentrations of trigonelline, nicotinic acid, and caffeine in instant coffee, roasted coffee, and raw coffee (Yunnan Arabica coffee) were assessed by MAE and hot water extraction; the correlation coefficients between concentrations of the three compounds obtained were close to 1.
Determination of Total Nitrofuran Metabolites in Shrimp Muscle Using Liquid Chromatography/Tandem Mass Spectrometry in the Atmospheric Pressure Chemical Ionization Mode
Authors: An Haejung , Henry Mark , Cain Teresa , Tran Bichsa , Paek Han Chol , Farley Dennis
Published: August 2012

The method of MacMahon and Lohne for analysis of nitrofuran metabolites in shrimp was optimized to streamline the extraction processes and the LC analysis. This revised method includes 16 h of mild acid hydrolysis/derivatization followed by ethyl acetate extraction and analysis by LC/MS/MS in the atmospheric pressure chemical ionization mode. This revised method was validated in shrimp for concentrations of 0.25 to 2.0 ng/g. The LOQ was 0.25 ng/g for all metabolites. The LOD was 0.052 ng/g for 1-aminohydantoin (AHD), 0.206 ng/g for 3-amino-2-oxazolidinone (AOZ), 0.108 ng/g for semicarbazide (SC), and 0.062 ng/g for 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ). The spike recoveries with RSD into negative matrix at 1 ng/g were 100.2% (3.2%) for AHD, 102.5% (1.0%) for AOZ, 103.7% (2.3%) for SC, and 104.0% (3.3%) for AMOZ. The spike recoveries at 1 ng/g into unknown samples (n = 108) containing varied levels of nitrofuran metabolites were 112.6% (25.7%) for AHD, 108.1% (12.1%) for AOZ, 103.0% (12.0%) for SC, and 100.3% (6.9%) for AMOZ. Interday precision with samples containing incurred AOZ concentrations of 0.92 to 17.8 ppb performed over a year was 10.4% RSD. The method is accurate and precise for determining nitrofuran concentrations in the edible tissue of shrimp.
Biennial Review of Planar Chromatography: 2009–2011
Authors: Sherma Joseph
Published: August 2012

The most important advances in the planar chromatography published between November 1, 2009 and November 1, 2011 are reviewed in this paper. Included are an introduction to the current status of the field; history, student experiments, books, and reviews; theory and fundamental studies; apparatus and techniques for sample preparation and TLC separations (sample application and plate development with the mobile phase); detection and identification of separated zones (chemical and biological detection, TLC/MS, and TLC coupled with other methods); techniques and instruments for quantitative analysis; preparative layer chromatography; and thin layer radiochromatography. Selected applications are given in the various sections of the review, especially for modern HPTLC-densitometry.
Templated Crosslinked Imidazolyl Acrylate for Electronic Detection of Nitroaromatic Explosives
Authors: Kong Hoyoul , Sinha Jasmine , Sun Jia , Katz Howard E.
Published: August 2012

A low‐voltage operable, highly sensitive, and selectively responsive polymer for the detection of nitroaromatic explosives is investigated. Resistive devices are fabricated by simple spin‐coating on flexible and transparent substrates in addition to silicon substrates and are stable under ambient temperature and oxygen levels before exposure to the nitroaromatics. After exposure to 2,4,6‐trinitrotoluene (TNT), the devices show increased conductance, even with picogram (pg) quantities of TNT, accompanied by a confirming color change from colorless to deep red. The relative conductance increase per unit exposure is the highest yet reported for TNT. Aromatic anion salts, on the other hand, do not induce any electronic responses. 1H NMR and microscopic analyses show chemical interactions and morphological changes correlated with the electronic responses, some of which are specific to TNT in relation to other nitroaromatics. The binding constant for the imidazole rings and TNT is on the order of tens of M−1. The materials are promising for rapid indication of exposure to nitroaromatic compounds.
siRNA Transfection with Calcium Phosphate Nanoparticles Stabilized with PEGylated Chelators
Authors: Giger Elisabeth V. , Castagner Bastien , Räikkönen Johanna , Mönkkönen Jukka , Leroux Jean‐Christophe
Published: August 2012

Despite the enormous therapeutic potential of siRNAs, their delivery is still problematic due to unfavorable biodistribution profiles and poor intracellular bioavailability. Calcium phosphate co‐precipitate has been used for nearly 40 years for in vitro transfection due to its non‐toxic nature and simplicity of preparation. However, rapid particle growth has largely prevented the translation of this method for in vivo purposes. It has recently been shown that bisphosphonate derivatives can physically stabilize calcium phosphate nanoparticles while still allowing for efficient cell transfection with plasmid DNA. Herein, two novel PEGylated chelating agents (PEG‐alendronate and PEG‐inositolpentakisphosphate) with enhanced stabilizing properties are introduced, and it is demonstrated that the bisphosphonate‐stabilized nanoparticles can efficiently deliver siRNA in vitro. The nanoparticles are mainly taken up by clathrin‐dependent endocytosis, and acidification of the endosomal compartment is required to release the entrapped siRNA into the cytosol. Furthermore, particle uptake enhances the inhibition of the mevalonate pathway by the bisphosphonate in macrophages.
Neovascularization in Biodegradable Inverse Opal Scaffolds with Uniform and Precisely Controlled Pore Sizes
Authors: Choi Sung‐Wook , Zhang Yu , MacEwan Matthew R. , Xia Younan
Published: August 2012

The formation of a stable vascular network in a scaffold is one of the most challenging tasks in tissue engineering and regenerative medicine. Despite the common use of porous scaffolds in these applications, little is known about the effect of pore size on the neovascularization in these scaffolds. Herein is fabricated poly(D, L‐lactide‐co‐glycolide) inverse opal scaffolds with uniform pore sizes of 79, 147, 224, and 312 μm in diameter and which are then used to systematically study neovascularization in vivo. Histology analyses reveal that scaffolds with small pores (<200 μm) favor the formation of vascular networks with small vessels at high densities and poor penetration depth. By contrast, scaffolds with large pores (>200 μm) favor the formation of vascular networks with large blood vessels at low densities and deep penetration depth. Based on the different patterns of vessel ingrowth as regulated by the pore size, a model is proposed to describe vascularization in a 3D porous scaffold, which can potentially serve as a guideline for future design of porous scaffolds.
Noninvasive Saliva Collection for DNA Analyses From Free‐Ranging Tibetan Macaques (Macaca thibetana)
Authors: SIMONS N. D. , LORENZ J. G. , SHEERAN L. K. , LI J. H. , XIA D. P. , Wagner R. S.
Published: August 2012

Cryptic and endangered fauna, including many primate taxa, pose challenges for noninvasive collection of biomaterials. As a result, application of noninvasive genotyping to primates has been limited to the use of samples such as feces and hair for the extraction of PCR‐amplifiable DNA. We present a method for noninvasive collection of saliva from habituated, free‐ranging monkeys. The method utilizes a low‐cost apparatus that controls for contamination and is usable with individual, free‐ranging primates. Saliva samples were collected from 18 individuals in a population of Tibetan macaques (Macaca thibetana) in the Valley of Wild Monkeys in Huangshan, People's Republic of China. DNA was extracted from these samples and PCR‐amplified for both mitochondrial and nuclear genes, Cytochrome B and MHC‐DR Beta 1, respectively. These results indicate this is an effective technique for the noninvasive collection of saliva across age and sex class, and dominance rank in a free‐ranging, terrestrial primate species. This device could have wide application for obtaining high‐quality saliva samples from free‐ranging primate populations for use in epidemiological studies, hormonal analyses of HPA axis function, pathogen screening, noninvasive genotyping, and behavioral genetics. Am. J. Primatol. 74:1064‐1070, 2012. © 2012 Wiley Periodicals, Inc.
Die “Renaissance” der radikalischen Trifluormethylierung
Authors: Studer Armido
Published: August 2012

Dieser Kurzaufsatz stellt jüngste Entwicklungen auf dem Gebiet radikalischer Trifluormethylierungen vor. Die Trifluormethylgruppe zählt zu den privilegierten Struktureinheiten in der Medizinalchemie. Viele Wirkstoffe und Wirkstoffkandidaten enthalten die Trifluormethylgruppe, und auch in Agrochemikalien findet sich oft eine CF3‐Einheit. Der vorliegende Kurzaufsatz befasst sich mit radikalischen Trifluormethylierungen von Alkenen und Arenen, wobei besonders auf die jüngsten Entwicklungen eingegangen wird; wichtige frühere Arbeiten werden jedoch ebenfalls diskutiert.
Overcoming the constraints of low sample sizes to produce age and growth data for rare or threatened sharks
Authors: Smart Jonathan J. , Harry Alastair V. , Tobin Andrew J. , Simpfendorfer Colin A.
Published: August 2012

Many sharks are listed as data deficient in assessment and management reports owing to a lack of basic life history data, making decisions about conservation management difficult. As such, the collection of these data is a priority. However, rare or threatened species with populations that are already small can be difficult to sample. Thus there is a need for techniques that permit the use of small sample sizes to provide preliminary information on life history parameters such as age and growth.

In this study, growth curves were fitted to length‐at‐age data for five rare or difficult to sample sharks from north‐eastern Australia: Carcharhinus coatesi (n = 56), Carcharhinus fitzroyensis (n = 39), Carcharhinus macloti (n = 37), Eusphyra blochii (n = 14) and Hemipristis elongata (n = 14) to provide the first estimates of growth for these species. Vertebral centra from field collections were aged to obtain length‐at‐age data, and partial age adjustments were used to increase the precision of age estimates. In addition, back calculation techniques were applied to add interpolated data to fill gaps in the growth curves caused by missing length classes.

Back calculation techniques did not substantially alter the growth curves of the species, which had an even spread of data across size classes (C. fitzroyensis, E. blochii and H. elongata). However, the back calculation techniques considerably improved the growth curves for C. coatesi and C. macloti where juveniles were missing from the samples.

Small sample sizes often provide a barrier to conducting growth studies because of the perception that growth estimates can only be obtained from ‘large’ sample sizes. However, by including individuals across all of the species length classes and maximizing the use of all available exogenous information using back calculation and partial age adjustments, as well as through judicious choice of growth models, it is possible to obtain practical estimates of growth, even when sample sizes are extremely limited. Copyright © 2012 John Wiley & Sons, Ltd.