bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping Tree Canopy Cover and Aboveground Biomass in Sudano-Sahelian Woodlands Using Landsat 8 and Random Forest
Authors: Karlson Martin , Ostwald Madelene , Reese Heather , Sanou Josias , Tankoano Boalidioa , Mattsson Eskil
Published: August 2015

Accurate and timely maps of tree cover attributes are important tools for environmental research and natural resource management. We evaluate the utility of Landsat 8 for mapping tree canopy cover (TCC) and aboveground biomass (AGB) in a woodland landscape in Burkina Faso. Field data and WorldView-2 imagery were used to assemble the reference dataset. Spectral, texture, and phenology predictor variables were extracted from Landsat 8 imagery and used as input to Random Forest (RF) models. RF models based on multi-temporal and single date imagery were compared to determine the influence of phenology predictor variables. The effect of reducing the number of predictor variables on the RF predictions was also investigated. The model error was assessed using 10-fold cross validation. The most accurate models were created using multi-temporal imagery and variable selection, for both TCC (five predictor variables) and AGB (four predictor variables). The coefficient of determination of predicted versus observed values was 0.77 for TCC (RMSE = 8.9%) and 0.57 for AGB (RMSE = 17.6 tons∙ha−1). This mapping approach is based on freely available Landsat 8 data and relatively simple analytical methods, and is therefore applicable in woodland areas where sufficient reference data are available.
Modeling Glacier Elevation Change from DEM Time Series
Authors: Wang Di , Kääb Andreas
Published: August 2015

In this study, a methodology for glacier elevation reconstruction from Digital Elevation Model (DEM) time series (tDEM) is described for modeling the evolution of glacier elevation and estimating related volume change, with focus on medium-resolution and noisy satellite DEMs. The method is robust with respect to outliers in individual DEM products. Fox Glacier and Franz Josef Glacier in New Zealand are used as test cases based on 31 Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) DEMs and the Shuttle Radar Topography Mission (SRTM) DEM. We obtained a mean surface elevation lowering rate of −0.51 ± 0.02 m·a−1 and −0.09 ± 0.02 m·a−1 between 2000 and 2014 for Fox and Franz Josef Glacier, respectively. The specific volume difference between 2000 and 2014 was estimated as −0.77 ± 0.13 m·a−1 and −0.33 ± 0.06 m·a−1 by our tDEM method. The comparably moderate thinning rates are mainly due to volume gains after 2013 that compensate larger thinning rates earlier in the series. Terminus thickening prevailed between 2002 and 2007.
Remote-Sensed Monitoring of Dominant Plant Species Distribution and Dynamics at Jiuduansha Wetland in Shanghai, China
Authors: Lin Wenpeng , Chen Guangsheng , Guo Pupu , Zhu Wenquan , Zhang Donghai
Published: August 2015

Spartina alterniflora is one of the most hazardous invasive plant species in China. Monitoring the changes in dominant plant species can help identify the invasion mechanisms of S. alterniflora, thereby providing scientific guidelines on managing or controlling the spreading of this invasive species at Jiuduansha Wetland in Shanghai, China. However, because of the complex terrain and the inaccessibility of tidal wetlands, it is very difficult to conduct field experiments on a large scale in this wetland. Hence, remote sensing plays an important role in monitoring the dynamics of plant species and its distribution on both spatial and temporal scales. In this study, based on multi-spectral and high resolution (<10 m) remote sensing images and field observational data, we analyzed spectral characteristics of four dominant plant species at different green-up phenophases. Based on the difference in spectral characteristics, a decision tree classification was built for identifying the distribution of these plant species. The results indicated that the overall classification accuracy for plant species was 87.17%, and the Kappa Coefficient was 0.81, implying that our classification method could effectively identify the four plant species. We found that the area of Phragmites australi showed an increasing trend from 1997 to 2004 and from 2004 to 2012, with an annual spreading rate of 33.77% and 31.92%, respectively. The area of Scirpus mariqueter displayed an increasing trend from 1997 to 2004 (12.16% per year) and a decreasing trend from 2004 to 2012 (−7.05% per year). S. alterniflora has the biggest area (3302.20 ha) as compared to other species, accounting for 51% of total vegetated area at the study region in 2012. It showed an increasing trend from 1997 to 2004 and from 2004 to 2012, with an annual spreading rate of 130.63% and 28.11%, respectively. As a result, the native species P. australi was surrounded and the habitats of S. mariqueter were occupied by S. alterniflora. The high proliferation ability and competitive advantage for S. alterniflora inhibited the growth of other plant species and we anticipate a continuous expansion of this invasive species at Jiuduansha Wetland. Effective measures should be taken to control the invasion of S. alterniflora.
Investment Strategy of Emission-Reduction Technology in a Supply Chain
Authors: Lou Gao , Xia Hai , Zhang Jie , Fan Ti
Published: August 2015

Greenhouse gas emissions have serious impacts on the natural environment. Therefore, the restrictions imposed on carbon emission force enterprises to take carbon emission into consideration when making production decisions. In this paper, in the context of allowing emission trading and investment of emission reduction technology, models were presented for a two-stage supply chain to analyze the optimal investment and pricing decisions. The results indicate that manufacturer’s endurance capacity of reduction difficulty is higher in the cooperation model than in the Stackelberg game model, and that perfect coordination of supply chains can be realized by a revenue sharing contract. From the perspective of a consumer, low-carbon products mean higher price, so that subsidies or tax exemptions should be provided to keep low prices. Meanwhile, the government can promote investment in emission-reduction technologies and achieve its emission reduction targets by controlling emission trading price, strengthening emission reduction publicity and providing technology investment subsidies.
Empirical Study Utilizing QFD to Develop an International Marketing Strategy
Authors: Elrod Cassandra , Stanley Sarah , Cudney Elizabeth , Fisher Caroline
Published: August 2015

Customer expectations can be extremely nebulous. This research identifies the demographic segmentations and their respective expectations for the spa market. Interviews were conducted and a subsequent questionnaire was employed to gather the voice of the customer and assess the expectations of spa clientele. All of the data was collected from luxury spas in Hawaii, and consisted of respondents from all over the world. Results of the survey suggest that while men want more tangible benefits of a spa, women prefer the experiential qualities of peace and rejuvenation. Additionally, those of lower to middle income focus on the atmosphere more than wealthier clients, who are looking for more long term spa benefits, such as a more youthful appearance.
Design of the Building Envelope: A Novel Multi-Objective Approach for the Optimization of Energy Performance and Thermal Comfort
Authors: Ascione Fabrizio , Bianco Nicola , De Masi Rosa , Mauro Gerardo , Vanoli Giuseppe
Published: August 2015

According to the increasing worldwide attention to energy and the environmental performance of the building sector, building energy demand should be minimized by considering all energy uses. In this regard, the development of building components characterized by proper values of thermal transmittance, thermal capacity, and radiative properties is a key strategy to reduce the annual energy need for the microclimatic control. However, the design of the thermal characteristics of the building envelope is an arduous task, especially in temperate climates where the energy demands for space heating and cooling are balanced. This study presents a novel methodology for optimizing the thermo-physical properties of the building envelope and its coatings, in terms of thermal resistance, capacity, and radiative characteristics of exposed surfaces. A multi-objective approach is adopted in order to optimize energy performance and thermal comfort. The optimization problem is solved by means of a Genetic Algorithm implemented in MATLAB®, which is coupled with EnergyPlus for performing dynamic energy simulations. For demonstration, the methodology is applied to a residential building for two different Mediterranean climates: Naples and Istanbul. The results show that for Naples, because of the higher incidence of cooling demand, cool external coatings imply significant energy savings, whereas the insulation of walls should be high but not excessive (no more than 13–14 cm). The importance of high-reflective coating is clear also in colder Mediterranean climates, like Istanbul, although the optimal thicknesses of thermal insulation are higher (around 16–18 cm). In both climates, the thermal envelope should have a significant mass, obtainable by adopting dense and/or thick masonry layers. Globally, a careful design of the thermal envelope is always necessary in order to achieve high-efficiency buildings.
Axonal Transport Impairment in Chemotherapy-Induced Peripheral Neuropathy
Authors: Nicolini Gabriella , Monfrini Marianna , Scuteri Arianna
Published: August 2015

Chemotherapy-Induced Peripheral Neuropathy (CIPN) is a dose-limiting side effect of several antineoplastic drugs which significantly reduces patients’ quality of life. Although different molecular mechanisms have been investigated, CIPN pathobiology has not been clarified yet. It has largely been recognized that Dorsal Root Ganglia are the main targets of chemotherapy and that the longest nerves are the most damaged, together with fast axonal transport. Indeed, this bidirectional cargo-specific transport has a pivotal role in neuronal function and its impairment is involved in several neurodegenerative and neurodevelopmental diseases. Literature data demonstrate that, despite different mechanisms of action, all antineoplastic agents impair the axonal trafficking to some extent and the severity of the neuropathy correlates with the degree of damage on this bidirectional transport. In this paper, we will examine the effect of the main old and new chemotherapeutic drug categories on axonal transport, with the aim of clarifying their potential mechanisms of action, and, if possible, of identifying neuroprotective strategies, based on the knowledge of the alterations induced by each drugs.
Citreoviridin Induces Autophagy-Dependent Apoptosis through Lysosomal-Mitochondrial Axis in Human Liver HepG2 Cells
Authors: Wang Yuexia , Liu Yanan , Liu Xiaofang , Jiang Liping , Yang Guang , Sun Xiance , Geng Chengyan , Li Qiujuan , Yao Xiaofeng , Chen Min
Published: August 2015

Citreoviridin (CIT) is a mycotoxin derived from fungal species in moldy cereals. In our previous study, we reported that CIT stimulated autophagosome formation in human liver HepG2 cells. Here, we aimed to explore the relationship of autophagy with lysosomal membrane permeabilization and apoptosis in CIT-treated cells. Our data showed that CIT increased the expression of LC3-II, an autophagosome biomarker, from the early stage of treatment (6 h). After treatment with CIT for 12 h, lysosomal membrane permeabilization occurred, followed by the release of cathepsin D in HepG2 cells. Inhibition of autophagosome formation with siRNA against Atg5 attenuated CIT-induced lysosomal membrane permeabilization. In addition, CIT induced collapse of mitochondrial transmembrane potential as assessed by JC-1 staining. Furthermore, caspase-3 activity assay showed that CIT induced apoptosis in HepG2 cells. Inhibition of autophagosome formation attenuated CIT-induced apoptosis, indicating that CIT-induced apoptosis was autophagy-dependent. Cathepsin D inhibitor, pepstatin A, relieved CIT-induced apoptosis as well, suggesting the involvement of the lysosomal-mitochondrial axis in CIT-induced apoptosis. Taken together, our data demonstrated that CIT induced autophagy-dependent apoptosis through the lysosomal-mitochondrial axis in HepG2 cells. The study thus provides essential mechanistic insight, and suggests clues for the effective management and treatment of CIT-related diseases.
RNA-Dependent RNA Polymerases of Picornaviruses: From the Structure to Regulatory Mechanisms
Authors: Ferrer-Orta Cristina , Ferrero Diego , Verdaguer Núria
Published: August 2015

RNA viruses typically encode their own RNA-dependent RNA polymerase (RdRP) to ensure genome replication within the infected cells. RdRP function is critical not only for the virus life cycle but also for its adaptive potential. The combination of low fidelity of replication and the absence of proofreading and excision activities within the RdRPs result in high mutation frequencies that allow these viruses a rapid adaptation to changing environments. In this review, we summarize the current knowledge about structural and functional aspects on RdRP catalytic complexes, focused mainly in the Picornaviridae family. The structural data currently available from these viruses provided high-resolution snapshots for a range of conformational states associated to RNA template-primer binding, rNTP recognition, catalysis and chain translocation. As these enzymes are major targets for the development of antiviral compounds, such structural information is essential for the design of new therapies.
Special Issue: Gene Therapy with Emphasis on RNA Interference
Authors: Lundstrom Kenneth
Published: August 2015

Gene therapy was originally thought to cover replacement of malfunctioning genes in treatment of various diseases. Today, the field has been expanded to application of viral and non-viral vectors for delivery of recombinant proteins for the compensation of missing or insufficient proteins, anti-cancer genes and proteins for destruction of tumor cells, immunostimulatory genes and proteins for stimulation of the host defense system against viral agents and tumors. Recently, the importance of RNA interference and its application in gene therapy has become an attractive alternative for drug development.
Mate-Pair Sequencing as a Powerful Clinical Tool for the Characterization of Cancers with a DNA Viral Etiology
Authors: Gao Ge , Smith David
Published: August 2015

DNA viruses are known to be associated with a variety of different cancers. Human papillomaviruses (HPV) are a family of viruses and several of its sub-types are classified as high-risk HPVs as they are found to be associated with the development of a number of different cancers. Almost all cervical cancers appear to be driven by HPV infection and HPV is also found in most cancers of the anus and at least half the cancers of the vulva, penis and vagina, and increasingly found in one sub-type of head and neck cancers namely oropharyngeal squamous cell carcinoma. Our understanding of HPVs role in cancer development comes from extensive studies done on cervical cancer and it has just been assumed that HPV plays an identical role in the development of all other cancers arising in the presence of HPV sequences, although this has not been proven. Most invasive cervical cancers have the HPV genome integrated into one or more sites within the human genome. One powerful tool to examine all the sites of HPV integration in a cancer but that also provides a comprehensive view of genomic alterations in that cancer is the use of next generation sequencing of mate-pair libraries produced from the DNA isolated. We will describe how this powerful technology can provide important information about the genomic organization within an individual cancer genome, and how this has demonstrated that HPVs role in oropharyngeal squamous cell carcinoma is distinct from that in cervical cancer. We will also describe why the sequencing of mate-pair libraries could be a powerful clinical tool for the management of patients with a DNA viral etiology and how this could quickly transform the care of these patients.
Spatiotemporal Distribution of Soil Moisture and Salinity in the Taklimakan Desert Highway Shelterbelt
Authors: Huang Yuan , Wang Yongdong , Zhao Ying , Xu Xinwen , Zhang Jianguo , Li Congjuan
Published: August 2015

Salinization and secondary salinization often appear after irrigation with saline water. The Taklimakan Desert Highway Shelterbelt has been irrigated with saline ground water for more than ten years; however, soil salinity in the shelterbelt has not been evaluated. The objective of this study was to analyze the spatial and temporal distribution of soil moisture and salinity in the shelterbelt system. Using a non-uniform grid method, soil samples were collected every two days during one ten-day irrigation cycle in July 2014 and one day in spring, summer, and autumn. The results indicated that soil moisture declined linearly with time during the irrigation cycle. Soil moisture was greatest in the southern and eastern sections of the study area. In contrast to soil moisture, soil electrical conductivity increased from 2 to 6 days after irrigation, and then gradually decreased from 6 to 8 days after irrigation. Soil moisture was the greatest in spring and the least in summer. In contrast, soil salinity increased from spring to autumn. Long time drip-irrigation with saline groundwater increased soil salinity slightly. The soil salt content was closely associated with soil texture. The current soil salt content did not affect plant growth, however, the soil in the shelterbelt should be continuously monitored to prevent salinization in the future.
Topical Referents for Individuals and Possibilities
Authors: Bittner Maria
Published: August 2015

No abstract.
Lexical Alternatives as a Source of Pragmatic Presuppositions
Authors: Abusch Dorit
Published: August 2015

No abstract.
Milsark's Generalization and Categorical Judgments
Authors: Kuroda S.-Y.
Published: August 2015

No abstract.
You Do What You Gotta Do, Or Why "must" Implies "will"
Authors: Werner Tom
Published: August 2015

No abstract.
Attitudes without Monsters: A Japanese Perspective
Authors: Ogihara Toshiyuki
Published: August 2015

No abstract.
Pronouns, Presuppositions, and Semantic Variation
Authors: Matthewson Lisa
Published: August 2015

No abstract.
'Even' and Biased Questions: The Case of Spanish 'Siquiera'
Authors: Alonso-Ovalle Luis
Published: August 2015

No abstract.
On the Licensing of Understating NPIs: Manipulating the domain of degrees for Japanese 'anmari' and 'sonnani'
Authors: Matsui Ai
Published: August 2015

Negative Polarity Items (NPIs) often have an effect of strengthening the statements which contain them. However, there are also NPIs that contribute to make a weaker claim such as all that (Israel 1996, 2006; van Rooy 2003). I analyze two kinds of such NPIs, namely the degree modiﬁer 'a(n)mari' and 'sonnani' in Japanese, which roughly translate as 'very/much' and '(all) that'. In doing so, two points are considered. First, since the NPIs in question are degree modiﬁers, I would like to adopt a degree-based semantics and combine it with the idea of domain widening proposed for determiner NPIs such as any. In particular, building on a version of Chierchia’s (2006) framework, I consider domain widening in terms of domains of degrees. Second, to capture the nature of understatement, I refer to the notion of quality-based strengthening, rather than informativity/entailment-based strengthening (Israel 2006; Krifka 1995; van Rooy 2003).
Investigating the alternative-sensitivity of "know"
Authors: Uegaki Wataru , Marty Paul
Published: August 2015

Several semantic analyses of know have been proposed in recent years to account for the so-called Gettier Problem. These analyses make distinct predictions regarding the sensitivity of know to the alternative possibilities expressed by its complement, as induced by expressions such as disjunction. These predictions were tested in two experiments. Results show that knowledge sentences with a disjunctive complement (e.g., John knows that Mary has a son or a daughter) are more likely to be judged as false than classically-equivalent sentences with non- disjunctive complements (e.g., John knows that Mary has a child) under Gettier-like scenarios. We discuss how these findings provide evidence for the alternative- sensitive approach to know.
On the Proper Treatment of Tense
Authors: Von Stechow Arnim
Published: August 2015

No abstract.
The Semantics of Relative Position
Authors: Zwarts Joost
Published: August 2015

No abstract.
Tense, Aspect, and Argument Structure
Authors: Ogihara Toshiyuki
Published: August 2015

No abstract.
Vitamin D Deficiency is Common in HIV-Infected Southern Australian Adults
Authors: Klassen Karen M , Fairley Christopher K , Kimlin Michael G , Hocking Jane , Kelsall Liza , Ebeling Peter R
Published: August 2015

Background

Vitamin D deficiency can have serious health consequences and may be particularly important for those living with HIV. It is unknown whether HIV infection is a risk factor for vitamin D deficiency. The aim of the study was to determine whether vitamin D deficiency is more common in HIV-infected than in HIV-uninfected individuals.

Methods

This was a cross-sectional study of HIV-infected and uninfected individuals. A total of 997 HIV-infected participants were from a sexual health clinic in Melbourne with 25(OH)D measurements taken between 2008 and 2012. 3,653 HIV-uninfected individuals were participants in a statewide Victorian survey with 25(OH)D measurements taken between 2009 and 2010. Logistic regression models evaluated the association of HIV status with vitamin D deficiency (25[OH]D<50 nmol/l).

Results

The frequency of vitamin D deficiency was significantly more common in HIV-infected (39% [95% CI 36%, 42%]) compared with HIV-uninfected individuals 23% (95% CI 15%, 31%). In multivariable analysis, males (adjusted odds ratio [aOR] 0.8; 95% CI 0.6, 0.9; P=0.001), Caucasian country of origin (aOR 0.4; 95% CI 0.3, 0.4; P<0.001), summer/autumn (aOR for autumn 0.2; 95% CI 0.1, 0.3; P<0.001), total cholesterol to high-density lipoprotein ratio >5 (aOR 1.4; 95% CI 1.2, 1.8; P<0.001) and HIV infection (aOR 1.7; 95% CI 1.4, 2.1; P<0.001) were associated with vitamin D deficiency.

Conclusions

Adults living in southern Australia with HIV were more likely to be vitamin D deficient than the general population.
Bioremediation of Pesticides under the Influence of Bacteria and Fungi
Authors: Mamta  , Rao Rayavarapu Jaganadha , Wani Khursheed Ahmad
Published: August 2015

The demand and development of chemicals, pesticides, fertilizers, and pharmaceuticals is increasing constantly posing a potential threat to the environment. The presence of pesticides and their impact makes their removal and detoxification a more urgent need. Bioremediation technologies have been successfully used and are gaining more and more importance with increased acceptance of eco-friendly remediation solutions among the scientific community. Bioremediation by fungi and bacteria is considered a better option for making environment free from pesticides, as chemical and physical methods are not only costly but also not very effective. However, the complex nature of pesticides is an obstacle to degrade the pesticides, so more versatile and robust microorganisms need to be identified which can produce the desired result in a very cost-effective manner. This study examines the role played by fungi and bacteria in degradation of the pesticides in environment and also identify the future research problems in this regard that need to be experimented.
Bioremediation of Oil Contaminated Soil and Water
Authors: Nanayakkara Chandrika Malkanthi , Witharana Ayoma
Published: August 2015

Pollution from petroleum, plant and animal origin oils, which are released via oil production and shipping operations, refineries, accidental spills, effluents of different industries such as hotels, restaurants, food processing, etc. is ubiquitous in the environment. This necessitates the need for cost effective and efficient remediation technologies. Dealing with the problem chemically and physically is known to generate secondary pollutants and incurs high cost. Expediting natural attenuation via stimulating pollutant degradation activity of residential microbial community and/or introducing competent microflora in to polluted sites has been identified as the most successful and cost effective technology and is termed bioremediation. Phytoremediation, an emerging branch of bioremediation, has also been recognized as a promising treatment technology. Chapter examines the extent of work carried out in in situ and ex situ bioremediation strategies to mitigate oil pollution, the validity of such practices in terms of efficiency of the process and the future research directives.
BASIC SPECIFIC GRAVITY AND ANATOMY OF Peltophorum dubium WOOD AS A FUNCTION OF PROVENANCE AND RADIAL POSITION
Authors: Lima Israel Luiz de , Longui Eduardo Luiz , Cerato Cintya , Freitas Miguel Luiz Menezes , Florsheim Sandra Monteiro Borges , Zanatto Antonio Carlos Scatena
Published: August 2015

We studied the wood of Peltophorum dubium (Spreng.) Taub. (Fabaceae), popularly known in Brazil as canafístula, from two seed provenances with different climates. The trees were planted in a third place and cut when 28 years old. Based on differences in seed origins, we hypothesized that some differences would be observed in wood density and anatomical features between provenances and that the radial variation pattern would also differ. However, we did not observe any differences in basic specific gravity or anatomical features between the provenances, which may partly be explained by the conservative nature of wood compared with the external characteristics more susceptible to environmental stresses. In fact, based on the literature and our previous findings, radial variation in P. dubium was similar to that found in many native species, including, for example, increase in basic specific gravity, length and wall thickness of the fibers, increase in vessel diameter and decrease in vessel frequency toward the bark. Based on our results, it can be concluded that P. dubium has high plant adaptability in different locations and that consistency in the quality of its wood can be maintained between provenances, with concomitant implications for both production and use.
Impact of the 2009 major sudden stratospheric warming on the composition of the stratosphere
Authors: Tao M. , Konopka P. , Ploeger F. , Grooß J.-U. , Müller R. , Volk C. M. , Walker K. A. , Riese M.
Published: August 2015

Abstract. In a case study of a remarkable major sudden stratospheric warming (SSW) during the boreal winter 2008/09, we investigate how transport and mixing triggered by this event affected the composition of the entire stratosphere in the Northern Hemisphere. We simulate this event with the Chemical Lagrangian Model of the Stratosphere (CLaMS), both with optimized mixing parameters and with no mixing, i.e. with transport occurring only along the Lagrangian trajectories. The results are investigated by using tracer–tracer correlations and by applying the transformed Eulerian-mean formalism. The CLaMS simulation of N2O and O3, and in particular of the O3–N2O tracer correlations with optimized mixing parameters, shows good agreement with the Aura Microwave Limb Sounder (MLS) data. The spatial distribution of mixing intensity in CLaMS correlates fairly well with the Eliassen–Palm flux convergence. This correlation illustrates how planetary waves drive mixing. By comparing simulations with and without mixing, we find that after the SSW, poleward transport of air increases, not only across the vortex edge but also across the subtropical transport barrier. Moreover, the SSW event, at the same time, accelerates polar descent and tropical ascent of the Brewer–Dobson circulation. The accelerated ascent in the tropics and descent at high latitudes first occurs in the upper stratosphere and then propagates downward to the lower stratosphere. This downward propagation takes over 1 month from the potential temperature level of 1000 to 400 K.
New calibration noise suppression techniques for the GLORIA limb imager
Authors: Guggenmoser T. , Blank J. , Kleinert A. , Latzko T. , Ungermann J. , Friedl-Vallon F. , Höpfner M. , Kaufmann M. , Kretschmer E. , Maucher G. , Neubert T. , Oelhaf H. , Preusse P. , Riese M. , Rongen H. , Sha M. K. , Sumińska-Ebersoldt O. , Tan V.
Published: August 2015

Abstract. The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) presents new opportunities for the retrieval of trace gases in the upper troposphere and lower stratosphere. The radiometric calibration of the measured signal is achieved using in-flight measurements of reference blackbody and upward-pointing "deep space" scenes. In this paper, we present techniques developed specifically to calibrate GLORIA data exploiting the instrument's imaging capability. The algorithms discussed here make use of the spatial correlation of parameters across GLORIA's detector pixels in order to mitigate the noise levels and artefacts in the calibration measurements. This is achieved by combining a priori and empirical knowledge about the instrument background radiation with noise-mitigating compression methods, specifically low-pass filtering and principal component analysis (PCA). In addition, a new software package for the processing of GLORIA data is introduced which allows us to generate calibrated spectra from raw measurements in a semi-automated data processing chain.
Retrieval algorithm for rainfall mapping from microwave links in a cellular communication network
Authors: Overeem A. , Leijnse H. , Uijlenhoet R.
Published: August 2015

Abstract. Microwave links in commercial cellular communication networks hold a promise for areal rainfall monitoring and could complement rainfall estimates from ground-based weather radars, rain gauges, and satellites. It has been shown that country-wide rainfall maps can be derived from the signal attenuations of microwave links in such a network. Here we give a detailed description of the employed rainfall retrieval algorithm and provide the corresponding code. Moreover, the code (in the scripting language "R") is made available including a data set of commercial microwave links. The purpose of this paper is to promote rainfall monitoring utilizing microwave links from cellular communication networks as an alternative or complementary means for global, continental-scale rainfall monitoring.
New image measurements of the gravity wave propagation characteristics from a low latitude Indian station
Authors: Sivakandan M. , Taori A. , Niranjan K.
Published: August 2015

Abstract. The image observations of mesospheric O(1S) 558 nm have been performed from a low latitude Indian station, Gadanki (13.5° N; 79.2° E) using a CCD based all sky camera system. Based on three years (from year 2012 to the year 2014) of image data during March–April, we characterize the small scale gravity wave properties. We noted 50 strong gravity wave event and 19 ripple events to occur. The horizontal wavelengths of the gravity waves are found to vary from 12 to 42 km with the phase velocity ranging from 20 to 90 km. In most cases, these waves were propagating towards north with only a few occasions of southward propagation. The outgoing longwave radiation data suggest that lower atmospheric convection was most possible reason for the generation of the waves observed in the airglow data.
Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry
Authors: Daellenbach K. R. , Bozzetti C. , Křepelová A. , Canonaco F. , Wolf R. , Zotter P. , Fermo P. , Crippa M. , Slowik J. G. , Sosedova Y. , Zhang Y. , Huang R.-J. , Poulain L. , Szidat S. , Baltensperger U. , Prévôt A. S. H. , El Haddad I.
Published: August 2015

Abstract. Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make impractical its deployment at sufficient sites to determine regional characteristics. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical nature and contributing sources. In this study, we utilize the AMS to characterize the water-soluble organic fingerprint of ambient particles collected onto conventional quartz filters, which are routinely sampled at many air quality sites. The method was applied to 256 particulate matter (PM) filter samples (PM1, PM2.5, PM10) collected at 16 urban and rural sites during summer and winter. We show that the results obtained by the present technique compare well with those from co-located online measurements, e.g. AMS or Aerosol Chemical Speciation Monitor (ACSM). The bulk recoveries of organic aerosol (60–91 %) achieved using this technique, together with low detection limits (0.8 μg of organic aerosol on the analyzed filter fraction) allow its application to environmental samples. We will discuss the recovery variability of individual hydrocarbon, oxygen containing and other ions. The performance of such data in source apportionment is assessed in comparison to ACSM data. Recoveries of organic components related to different sources as traffic, wood burning and secondary organic aerosol are presented. This technique, while subjected to the limitations inherent to filter-based measurements (e.g. filter artifacts and limited time resolution) may be used to enhance the AMS capabilities in measuring size-fractionated, spatially-resolved long-term datasets.
Nitrogen fixation and the diazotroph community in the temperate coastal region of the northwestern North Pacific
Authors: Shiozaki T. , Nagata T. , Ijichi M. , Furuya K.
Published: August 2015

Abstract. Nitrogen fixation in temperate oceans is a potentially important, but poorly understood process that may influence the marine nitrogen budget. This study determined seasonal variations in nitrogen fixation and the diazotroph community within the euphotic zone in the temperate coastal region of the northwestern North Pacific. Nitrogen fixation as high as 13.6 nmol N L−1 d−1 was measured from early summer to fall when the surface temperature exceeded 14.2 °C (but was lower than 24.3 °C) and the surface nitrate concentration was low (≤ 0.30 μM), although we also detected nitrogen fixation in subsurface layers (42–62 m) where nitrate concentrations were high (> 1 μM). Clone library analysis results indicated that nifH gene sequences were omnipresent throughout the investigation period. During the period when nitrogen fixation was detected (early summer to fall), the genes affiliated with UCYN-A, Trichodesmium, and γ-proteobacterial phylotype γ-24774A11 were frequently recovered. In contrast, when nitrogen fixation was undetectable (winter to spring), many sequences affiliated with Cluster III diazotrophs (putative anaerobic bacteria) were recovered. Quantitative PCR analysis revealed that UCYN-A was relatively abundant from early to late summer compared with Trichodesmium and γ-24774A11, whereas Trichodesmium abundance was the highest among the three groups during fall.
Changes in soil carbon, nitrogen, and phosphorus due to land-use changes in Brazil
Authors: Groppo J. D. , Lins S. R. M. , Camargo P. B. , Assad E. D. , Pinto H. S. , Martins S. C. , Salgado P. R. , Evangelista B. , Vasconcellos E. , Sano E. E. , Pavão E. , Luna R. , Martinelli L. A.
Published: August 2015

Abstract. In this paper, soil carbon, nitrogen and phosphorus concentrations and stocks were investigated in agricultural and natural areas in 17 plot-level paired sites and in a regional survey encompassing more than 100 pasture soils In the paired sites, elemental soil concentrations and stocks were determined in native vegetation (forests and savannas), pastures and crop–livestock systems (CPSs). Nutrient stocks were calculated for the soil depth intervals 0–10, 0–30, and 0–60 cm for the paired sites and 0–10, and 0–30 cm for the pasture regional survey by sum stocks obtained in each sampling intervals (0–5, 5–10, 10–20, 20–30, 30–40, 40–60 cm). Overall, there were significant differences in soil element concentrations and ratios between different land uses, especially in the surface soil layers. Carbon and nitrogen contents were lower, while phosphorus contents were higher in the pasture and CPS soils than in native vegetation soils. Additionally, soil stoichiometry has changed with changes in land use. The soil C : N ratio was lower in the native vegetation than in the pasture and CPS soils, and the carbon and nitrogen to available phosphorus ratio (PME) decreased from the native vegetation to the pasture to the CPS soils. In the plot-level paired sites, the soil nitrogen stocks were lower in all depth intervals in pasture and in the CPS soils when compared with the native vegetation soils. On the other hand, the soil phosphorus stocks were higher in all depth intervals in agricultural soils when compared with the native vegetation soils. For the regional pasture survey, soil nitrogen and phosphorus stocks were lower in all soil intervals in pasture soils than in native vegetation soils. The nitrogen loss with cultivation observed here is in line with other studies and it seems to be a combination of decreasing organic matter inputs, in cases where crops replaced native forests, with an increase in soil organic matter decomposition that leads to a decrease in the long run. The main cause of the increase in soil phosphorus stocks in the CPS and pastures of the plot-level paired site seems to be linked to phosphorus fertilization by mineral and organics fertilizers. The findings of this paper illustrate that land-use changes that are currently common in Brazil alter soil concentrations, stocks and elemental ratios of carbon, nitrogen and phosphorus. These changes could have an impact on the subsequent vegetation, decreasing soil carbon and increasing nitrogen limitation but alleviating soil phosphorus deficiency.
Late Pleistocene glacial–interglacial shell-size–isotope variability in planktonic foraminifera as a function of local hydrography
Authors: Metcalfe B. , Feldmeijer W. , de Vringer-Picon M. , Brummer G.-J. A. , Peeters F. J. C. , Ganssen G. M.
Published: August 2015

Abstract. So-called "vital effects" are a collective term for a suite of physiologically and metabolically induced variability in oxygen (δ18O) and carbon (δ13C) isotope ratios of planktonic foraminifer shells that hamper precise quantitative reconstruction of past ocean parameters. Correction for potential isotopic offsets from equilibrium or the expected value is paramount, as too is the ability to define a comparable life stage for each species that allows for direct comparison. Past research has focused upon finding a specific size range for individual species in lieu of other identifiable features, thus allowing ocean parameters from a particular constant (i.e. a specific depth or season) to be reconstructed. Single-shell isotope analysis of fossil shells from a mid-latitude North Atlantic Ocean piston core covering Termination III (200 to 250 ka) highlight the advantage of using a dynamic size range, i.e. utilising measurements from multiple narrow sieve size fractions spanning a large range of total body sizes, in studies of palaeoclimate. Using this methodology, we show that isotopic offsets between specimens in successive size fractions of Globorotalia inflata and Globorotalia truncatulinoides are not constant over time, contrary to previous findings. For δ18O in smaller-sized globorotalids (212–250 μm) it is suggested that the offset from other size fractions may reflect a shallower habitat in an early ontogenetic stage. A reduction in the difference between small and large specimens of G. inflata between insolation minima and maxima is interpreted to relate to a prolonged period of reduced water column stratification. For the shallow-dwelling species Globigerina bulloides, no size–isotope difference between size fractions is observed, and the variability in the oxygen isotopic values is shown to correlate well with the seasonal insolation patterns. As such, patterns in oxygen isotope variability of fossil populations may be used to reconstruct past seasonality changes.
The impact of sedimentary alkalinity release on the water column CO2 system in the North Sea
Authors: Brenner H. , Braeckman U. , Le Guitton M. , Meysman F. J. R.
Published: August 2015

Abstract. Recently, it has been proposed that alkalinity release from sediments can play an important role in the carbonate dynamics on continental shelves, lowering the pCO2 of seawater and hence increasing the CO2 uptake from the atmosphere. To test this hypothesis, sedimentary alkalinity generation was quantified within permeable and muddy sediments across the North Sea during two cruises in September 2011 (basin-wide) and June 2012 (Dutch coastal zone). Benthic fluxes of alkalinity (AT) and dissolved inorganic carbon (DIC) were determined using shipboard closed sediment incubations. These results show that sediments can be an important source for alkalinity, particularly in the shallow southern North Sea, where high AT and DIC fluxes were recorded in near shore sediments of the Belgian, Dutch and German coastal zone. In contrast, fluxes of AT and DIC are substantially lower in the deeper, seasonally stratified, northern part of the North Sea. Overall, our results show that sedimentary alkalinity generation should be considered an important factor in the CO2 dynamics of shallow coastal systems.
Optimizing the impact of temperature on bio-hydrogen production from food waste and its derivatives under no pH control using statistical modelling
Authors: Sattar A. , Arslan C. , Ji C. , Sattar S. , Yousaf K. , Hashim S.
Published: August 2015

Abstract. The effect of temperature on bio-hydrogen production by co-digestion of sewerage sludge with food waste and its two derivatives, i.e. noodle waste and rice waste, was investigated by statistical modelling. Experimental results showed that increasing temperature from mesophilic (37 °C) to thermophilic (55 °C) was an effective mean for increasing bio-hydrogen production from food waste and noodle waste, but it caused a negative impact on bio-hydrogen production from rice waste. The maximum cumulative bio-hydrogen production of 650 mL was obtained from noodle waste under mesophilic temperature condition. Most of the production was observed during 48 h of incubation that continued till 72 h of incubation, and a decline in pH during this interval was 4.3 and 4.4 from a starting value of 7 under mesophilic and thermophilic conditions, respectively. Most of glucose consumption was also observed during 72 h of incubation and the maximum consumption was observed during the first 24 h, which was the same duration where the maximum pH drop occurred. The maximum hydrogen yields of 82.47 mL VS−1, 131.38 mL COD−1, and 44.90 mL glucose−1 were obtained from mesophilic food waste, thermophilic noodle waste and mesophilic rice waste respectively. The production of volatile fatty acids increased with an increase in time and temperature from food waste and noodle waste reactors whereas it decreased with temperature in rice waste reactors. The statistical modelling returned good results with high values of coefficient of determination (R2) for each waste type when it was opted for the study of cumulative hydrogen production, glucose consumption and volatile fatty acid production. The 3-D response surface plots developed by the statistical models helped a lot in developing better understanding of the impact of temperature and incubation time.
Impacts of beaver dams on hydrologic and temperature regimes in a mountain stream
Authors: Majerova M. , Neilson B. T. , Schmadel N. M. , Wheaton J. M. , Snow C. J.
Published: August 2015

Abstract. Beaver dams affect hydrologic processes, channel complexity, and stream temperature in part by inundating riparian areas, influencing groundwater–surface water interactions, and changing fluvial processes within stream systems. We explored the impacts of beaver dams on hydrologic and temperature regimes at different spatial and temporal scales within a mountain stream in northern Utah over a 3-year period spanning pre- and post-beaver colonization. Using continuous stream discharge, stream temperature, synoptic tracer experiments, and groundwater elevation measurements, we documented pre-beaver conditions in the first year of the study. In the second year, we captured the initial effects of three beaver dams, while the third year included the effects of ten dams. After beaver colonization, reach-scale (~ 750 m in length) discharge observations showed a shift from slightly losing to gaining. However, at the smaller sub-reach scale (ranging from 56 to 185 m in length), the discharge gains and losses increased in variability due to more complex flow pathways with beaver dams forcing overland flow, increasing surface and subsurface storage, and increasing groundwater elevations. At the reach scale, temperatures were found to increase by 0.38 °C (3.8 %), which in part is explained by a 230 % increase in mean reach residence time. At the smallest, beaver dam scale (including upstream ponded area, beaver dam structure, and immediate downstream section), there were notable increases in the thermal heterogeneity where warmer and cooler niches were created. Through the quantification of hydrologic and thermal changes at different spatial and temporal scales, we document increased variability during post-beaver colonization and highlight the need to understand the impacts of beaver dams on stream ecosystems and their potential role in stream restoration.
Impact of model developments on present and future simulations of permafrost in a global land-surface model
Authors: Chadburn S. E. , Burke E. J. , Essery R. L. H. , Boike J. , Langer M. , Heikenfeld M. , Cox P. M. , Friedlingstein P.
Published: August 2015

Abstract. There is a large amount of organic carbon stored in permafrost in the northern high latitudes, which may become vulnerable to microbial decomposition under future climate warming. In order to estimate this potential carbon–climate feedback it is necessary to correctly simulate the physical dynamics of permafrost within global Earth system models (ESMs) and to determine the rate at which it will thaw. Additional new processes within JULES, the land-surface scheme of the UK ESM (UKESM), include a representation of organic soils, moss and bedrock and a modification to the snow scheme; the sensitivity of permafrost to these new developments is investigated in this study. The impact of a higher vertical soil resolution and deeper soil column is also considered. Evaluation against a large group of sites shows the annual cycle of soil temperatures is approximately 25 % too large in the standard JULES version, but this error is corrected by the model improvements, in particular by deeper soil, organic soils, moss and the modified snow scheme. A comparison with active layer monitoring sites shows that the active layer is on average just over 1 m too deep in the standard model version, and this bias is reduced by 70 cm in the improved version. Increasing the soil vertical resolution allows the full range of active layer depths to be simulated; by contrast, with a poorly resolved soil at least 50 % of the permafrost area has a maximum thaw depth at the centre of the bottom soil layer. Thus all the model modifications are seen to improve the permafrost simulations. Historical permafrost area corresponds fairly well to observations in all simulations, covering an area between 14 and 19 million km2. Simulations under two future climate scenarios show a reduced sensitivity of permafrost degradation to temperature, with the near-surface permafrost loss per degree of warming reduced from 1.5 million km2 °C−1 in the standard version of JULES to between 1.1 and 1.2 million km2 °C−1 in the new model version. However, the near-surface permafrost area is still projected to approximately half by the end of the 21st century under the RCP8.5 scenario.