bluuebunny/crossref_metadata_2025 huggingface dataset:
The Controlled Discipline of Servant Leaders
Authors: Buford Maurice A. , Gomez Doris , Patterson Kathleen , Winston Bruce E.
Published: April 2014

This chapter investigates claims by Johnson (2001) and Bowie (2000) that servant leaders tend not to assert authority. Twenty servant leaders were asked five open-ended questions about their use of discipline with outcomes of the discipline ranging from more training for subordinates to termination. Analysis of the responses resulted in 39 themes and 8 qualitative truths about servant leaders' use of discipline. Participants were included in the study if: (a) each scored above 3.5 on the Shepherd Leadership Inventory, (b) were leading or have led a team of at least three followers, and (c) held such a position for at least three years. This study provides a qualitative base for future research into servant leaders' use of discipline.
Servant Leadership and School Crisis Management
Authors: Geer Gregory , Coleman Howard V.
Published: April 2014

In today's world, public school leaders are often called upon to deal with tragedies that include suicides, homicides, and accidental deaths. When these incidents occur in small school districts, the roles and responsibilities of school personnel become those of counselors and civic leaders. This chapter presents a case study about the experiences of a school superintendent practicing servant leadership to help heal a small community when dealing with the accidental deaths of a local family. The superintendent's responses to the tragedy are based upon the foundations of servant leadership that include empathy, mental models, reflection, self-awareness, emotional healing, listening, commitment, and community building (Goen, 2009; Spears, 2004; Greenleaf, 1977). Servant leadership practices help guide educational leaders in providing support for students, teachers, and parents in school crises.
African American Urban School Principal Servant Leadership
Authors: Hozien Wafa
Published: April 2014

The purpose of this chapter is to investigate the characteristics of African American school principals and the obstacles they experience on their path to the principalship. A secondary purpose, but very important as well, is to analyze critically the experiences of successful African American male principals to help inform the preparation of principals who lead organizations of diverse demographics. Investigating this area also contributes to the much-needed educational discourse of African American principal attitudes, beliefs, and life experiences of principals in education today, and how they are meeting the needs of a growing multicultural population. The principals are the primary units of analysis, and it is the intent of this chapter to delve into the lives of the participants to gain a better understanding of the barriers and obstacles they have to overcome to become principals.
The Impact of Faith on Servant Leadership and Leadership Behavior
Authors: Puls Timothy R.
Published: April 2014

The objective of this chapter is to describe a couple of the deepest, compelling antecedents or schemata that shape personal faith and spiritual beliefs as well as two behaviors that exude outwardly toward followers of servant leaders. The first three core leadership points are strongly based on the theoretical model of Phipps (2012). The first core subject is a leader's personal spiritual beliefs, schema, or worldview. The existential worldview, as categorized by Koltko-Rivera (2004), shares the Christian worldview as a prototypical basis for servant leadership. The second core subject is a leader's constructive development or life experience, which shapes a leader's thinking (Phipps, 2012). This entails how a leader learns, processes, and makes meaning by reflecting on the school of personal experience, including trials and crucibles. The third core subject is more of a leader outcome, called meta-belief. A servant leader utilizes meta-belief or self-awareness in order to make choices in particular places and contexts. Finally, the fourth core essential subject that is evident to followers of servant leaders is vision and hope. A hopeful leader is always optimistically looking ahead with foresight, knowing what has taken place in both the past and present.
Historical Derivative of Servant Leadership and the Untold Story of the Influence of Quakerism on Greenleaf's Teachings
Authors: Beaver Tiffany L.
Published: April 2014

Robert Greenleaf reignited an interest in servant leadership; however, the concept is far from nascent. The multivariate religious influences glistening throughout servant leadership, orchestrate a mosaic imbued with benevolence and service. Although servant leadership transcends religion, the Quaker influence on how Greenleaf approached and taught servant leadership is significant yet gregariously absent in the literature. This chapter navigates the unexplored relationship between servant leadership and Quakerism. The chapter additionally encourages more widespread adoption of Smith's servant leadership paradigm, which goes beyond inverting the leadership paradigm and instead blurs the lines between leading and following, resembling a neurological infrastructure. The kaleidoscopic shift that servant leadership imbues maximizes the powerhouse of knowledge inherent in all organizations.
Distributing Power through Curriculum Development
Authors: Cranton Patricia
Published: April 2014

This chapter explores how power can be distributed in the process of curriculum and program development in adult and higher education. As a theoretical framework, the author relies on Brookfield's writings on power and, in turn, Foucault's writing on power, which has had a strong influence on the thinking of adult education scholars. From there, she turns to practical strategies for distributing power through curriculum development. These include: learners' selection of topics, learners' setting of objectives, learners' selecting methods and materials, learner self-evaluation, equitable discussions, questioning styles, and structural issues. Finally, the author explores future directions for research.
All Roads Lead to Curriculum Inclusive of Social Justice and Democracy
Authors: Wang Victor X. , Russo Marianne Robin , Bryan Valerie C.
Published: April 2014

Developing curricula requires instructors to take into account several factors. These factors can be viewed as critical components of curriculum development for education instructors. Without adequately addressing critical components such as curriculum history, curriculum theory, curriculum philosophies, curriculum processes, curriculum implementation, and evaluation, education instructors will fail to develop sound/meaningful curriculum(s). This chapter sheds light on relevant information from curriculum on its history, theory, philosophies of development, processes, implementation, and evaluation. The value of such as review is to assist those individuals seeking a teaching credential in education to have confidence to blend curriculum development with their prior occupational knowledge and skills. The chapter also examines caveats and dangers when social and political constructs are overlaid in comportments.
Transformative Curriculum Design and Program Development
Authors: Norris Sharon E.
Published: April 2014

The objective of this chapter is to introduce improvisational self-directed learning as a transformative approach to developing effective adult learning. Improvisational self-directed learning is a method that encourages individuals to leverage their psychological capital and self-directedness through the exercise of human agency. It is common practice to focus on content-related learning objectives while designing educational curriculum and programs. Less routine is a simultaneous focus on the psychological state, human agency, and self-directedness of those involved in the entire process. The type of transformative learning communities necessary for effective 21st century adult education require ongoing faculty and student development. This chapter provides a theoretical framework based on human agency, psychological capital, improvisational behavior, and adult learning. The use of improvisation is presented as a technique for leveraging psychological capital, human agency, and self-directedness to create thriving 21st century learning communities.
Using Creativity to Facilitate an Engaged Classroom
Authors: Sedivy-Benton Amy L. , Fetterly James M. , Wood Betty K. , MacFarlane Bronwyn D.
Published: April 2014

Student achievement, learning, and engagement are at the forefront of the educational concerns for both school administrators and teachers. While it seems to be common knowledge that engaged students tend to retain more from the lesson, a bigger question is how does a teacher create lessons that lead to this engagement? How can teachers structure these learning experiences in a creative way to obtain their objectives? One approach to this is by designing lessons with creative brainstorming to promote different ways of thinking. Creativity is the springboard that allows for critical thinking and engagement. The first instance of this should be in the planning of lessons. This chapter demonstrates how a simple lesson can be redesigned through creative practices and concludes with a checklist that can be used by school administrators, program coordinators, and teachers to quickly evaluate how engaging and creative their teaching truly is.
Dynamics of Informal Learning in Two Local Markets in Ile-Ife, Southwest Nigeria
Authors: Akinsooto Tajudeen Ade , Mejiuni Olutoyin
Published: April 2014

In this chapter, the authors report on a recently concluded research study of the nature of adult informal learning in two local markets in Ile-Ife, Nigeria. Through case study research design, the authors explore what adult buyers and sellers learn as they interact in two local markets, who learned from who, and how they acquire the specific learning experiences identified. They examine the factors that drove learning and provide an explanation, a substantive theory of informal learning in the two local markets, which they name Communication, Value, and Profit (CVP).
Comparison of Avifaunal Composition in a Natural and Regenerated Forest; Towards using Birds as Ecological Indicators
Authors: De Silva Thilina , Ranawana KB , Fernando Sumudu , Ellepola Gajaba
Published: April 2014

Tropical forests have been extensively exploited and cleared for various reasons over the past years.  Therefore, conservation emphasis has been given to protect natural forests and to assist regeneration of secondary forests.  In the current study  the composition and abundance of bird species in a natural forest (NF) and an adjacent regenerating forest (RF) in Maragamuwa, Naula in the Matale District of Sri Lanka were compared using a point count integrated line transect method.  A clear variation was seen in the bird composition, diversity and evenness in both forest types and also during different time sessions of the day.  In all the instances the values shown by the RF was greater than that of the NF and the species evenness showed high values for both forest types.  The species composition showed no seasonal variation in NF throughout the study period while RF showed a seasonal variation.  The endemicity of birds in the NF was higher than that of the RF. Hence, the current study shows that early successional forests support a rich bird diversity while the species richness of endemic bird species increases thereby enabling these measurements to be used as indicators in long term conservational practices.DOI: http://dx.doi.org/10.4038/cjsbs.v42i2.6610 Ceylon Journal of Science (Bio. Sci.) 42(2): 71-78, 2013
The Difficulty in Estimating the Total Population Size of Wild Elephants in Sri Lanka
Authors: Santiapillai Charles
Published: April 2014

DOI: http://dx.doi.org/10.4038/cjsbs.v42i2.6614 Ceylon Journal of Science (Bio. Sci.) 42(2): 101-103, 2013
Pellagra: A Non-Eradicated Old Disease
Authors: Savvidou Savvoula
Published: April 2014

We report a case of a 50-year old homeless male who presented with pellagra and pellagrous encephalopathy. The characteristic - if not pathognomonic - skin lesions of pellagra support its diagnosis on solely clinical grounds. Clinicians should keep a high index of suspicion, in certain patient groups, in order to early diagnose and cure this potentially fatal but treatable disease.
The Importance of Multidisciplinary Approach in Early Detection of BAP1 Tumor Predisposition Syndrome: Clinical Management and Risk Assessment
Authors: Battaglia Angelo
Published: April 2014

Germline BAP1 (BRCA1-associated protein-1) mutations are involved into a novel specific cancer syndrome and strictly associated with a high cancer susceptibility. Recent data suggest that BAP1 has activity toward target substrates explaining why loss of BAP1 causes a pro-tumorigenic deregulation of gene expression. The recently published data reviewed raise the hypothesis that BAP1 regulates a common subset of substrates, which in turn causes a pro-tumorigenic deregulation of gene expression, and alternatively suggest the role of BAP1 as tumorigenesis suppressor/promoter also by independent mechanisms. The clinical phenotype of BAP1 alterations includes MBAITs (melanocytic BAP1-mutated atypical intradermal tumors), uveal melanoma (UM), cutaneous melanoma (CM), renal cell carcinoma (RCC), mesothelioma (MM), and possibly several other tumors. In clinical practice, early diagnosis is crucial for curative resection of all these tumor types. The uniformed and unambiguous definition of MBAITs as clinical/pathological predictive markers could provide physicians means to identify patients who may carry germline BAP1 mutations and thus could be at high risk of developing CM, UM, MM, RCC, and possibly other tumors. As part of a novel multidisciplinary approach, physicians, pathologists, and clinicians involved into diagnostics should be aware of the histological features and the spectrum of tumors associated with BAP1 loss. Further clinical, epidemiological, and functional studies are required to fully explain the roles of BAP1 and its interaction partners in neoplasia, to define mechanisms behind shared and non-shared clinical and pathological criteria.
Patients’ Perception on the Nutritional Therapy for Diabetic Nephropathy
Authors: Shide Kenichiro , Takada Yuka , Nakashima Asuka , Tsuji Hidemi , Wada Keiko , Kuwabara Akiko , Tanaka Kiyoshi , Inagaki Nobuya
Published: April 2014

Low protein diet (LPD) plays an important role in preventing the progression of diabetic nephropathy. However, it is a great burden to the patients. In this paper, we have studied the quality of life (QOL) in such patients.

The study subjects were 59 patients (male 38, female 21) with type 2 diabetes. The patients were classified into tertiles based on their protein intake (g/kg BW). Scores from the diet-related QOL questionnaire were summarized by principal component analysis into four components; mental health, less burden, satisfaction and merit, and less social restriction.

Higher protein intake was associated with less burden and less social restriction. In multiple regression analysis, the significant predictors for the “less burden” component were higher protein intake/BW and estimated glomerular filtration rate (eGFR).

In summary, registered dietitians and clinicians must keep in mind that LPD is a serious burden to the patients and efforts must be made to minimize their burden in order to avoid discontinuation.
Efficacy and Side Effects of Natalizumab Therapy in Patients with Multiple Sclerosis
Authors: Hoepner Robert , Faissner Simon , Salmen Anke , Gold Ralf , Chan Andrew
Published: April 2014

Natalizumab (Nat) is a humanized monoclonal antibody used for the treatment of relapsing multiple sclerosis (MS). Nat inhibits lymphocyte migration via the blood brain barrier (BBB) by blockage of an integrin adhesion molecule, very late antigen 4. During the phase III clinical trials, it was shown that Nat reduces disease activity and prevents disability progression. In addition, several smaller studies indicate a positive influence of Nat on cognition, depression, fatigue, and quality of life (Qol). Therapeutic efficacy has to be weighed against the risk of developing potentially fatal progressive multifocal leukoencephalopathy (PML), an opportunistic infection by JC-virus (JCV) with an incidence of 3.4/1000 (95% CI 3.08–3.74) in Nat treated MS patients. In this review article, we will review data on the presumed mechanism of Nat action, clinical and paraclinical efficacy parameters, and adverse drug reactions with a special focus on PML.
‘[H]et dier in al zijn toonaarden’ - Over zoöpoëticale configuraties in Charlotte Mutsaers’ beeldend en literair werk
Authors: Fraipont Barbara
Published: April 2014

This article aims to highlight the prominent place and role of the animal in the literary and visual work of the Dutch writer and artist Charlotte Mutsaers (1942-). The border-crossing between human and animal will be dealt with on the basis of the interaction between image and text in Mutsaers’s oeuvre. In this intermedial perspective, I first focus on three images of Mutsaers’s visual work exemplifying the human-animal masquerade. Secondly, I consider her novel Koetsier Herfst (2008) in which the animal also enacts a crucial function through the figurative and performative force of Mutsaers’s writing. Recent research in the field of Cultural and Literary Animal Studies (CLAS) and ethico-philosophical reflections are used as theoretical frame. Starting from Steve Baker’s ‘representational strategies’ (1993) of the animal (i.e. theriomorphism and therianthropism) and Gilles Deleuze’s theory on the ‘becoming-animal’, this article sheds new light on the subversive functions and non-restrictive meaning of the animal in Mutsaers’s artistic practice in the broadest sense of the word. The analysed figurative strategies in Mutsaers’s work bring a significant reversal of perspective to light: from the human to the animal.
Bedrieglijk betoog - Auteursintentie en interpretatie van Hermans’ ‘Preambule’
Authors: op de Weegh Arne
Published: April 2014

Willem Frederik Hermans’s second collection of short stories, Paranoia (1953), opens with a short prose piece entitled ‘Preambule’ that for decades has been regarded as an introductory essay to the book. The italicized sentence ‘There is only one real word: chaos’ has often been understood as summary of the author’s own epistemological views. However, Hermans himself always insisted that ‘Preambule’ was a story; but the author’s claim has had little impact on its reception. This essay first brings together various explicit or implicit authorial indicators of the genre of ‘Preambule’, ranging from its typographical presentation to explanations in interviews. Second, against the background of the fundamental pattern underlying Hermans’s creative work as established in Hermans scholarship, I attempt to provide a coherent interpretation of the piece as a story, with an argument centered on but not limited to a comparison of the protagonist’s philosophy of language with his own practice. I argue that the narrator turns out to be a self-caricature rather than a genuine self-portrait. The essay concludes by assessing how the story fits into the group of stories that make up the collection, and whether there is any significant order involved.
Dimers in α-pinene secondary organic aerosol: effect of hydroxyl radical, ozone, relative humidity and aerosol acidity
Authors: Kristensen K. , Cui T. , Zhang H. , Gold A. , Glasius M. , Surratt J. D.
Published: April 2014

Abstract. The formation of secondary organic aerosol (SOA) from both ozonolysis and hydroxyl radical (OH)-initiated oxidation of α-pinene under conditions of high nitric oxide (NO) concentrations with varying relative humidity (RH) and aerosol acidity was investigated in the University of North Carolina dual outdoor smog chamber facility. SOA formation from ozonolysis of α-pinene was enhanced relative to that from OH-initiated oxidation in the presence of initially high-NO conditions. However, no effect of RH on SOA mass was evident. Ozone (O3)-initiated oxidation of α-pinene in the presence of ammonium sulfate (AS) seed coated with organic aerosol from OH-initiated oxidation of α-pinene showed reduced nucleation compared to ozonolysis in the presence of pure AS seed aerosol. The chemical composition of α-pinene SOA was investigated by ultra-performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS), with a focus on the formation of carboxylic acids and high-molecular weight dimers. A total of eight carboxylic acids and four dimers were identified, constituting between 8 and 12% of the total α-pinene SOA mass. OH-initiated oxidation of α-pinene in the presence of nitrogen oxides (NOx) resulted in the formation of highly oxidized carboxylic acids, such as 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA) and diaterpenylic acid acetate (DTAA). The formation of dimers was observed only in SOA produced from the ozonolysis of α-pinene in the absence of NOx, with increased concentrations by a factor of two at higher RH (50–90%) relative to lower RH (30–50%). The increased formation of dimers correlates with an observed increase in new particle formation at higher RH due to nucleation. Increased aerosol acidity was found to have a negligible effect on the formation of the dimers. SOA mass yield did not influence the chemical composition of SOA formed from α-pinene ozonolysis with respect to carboxylic acids and dimers. The results support the formation of the high-molecular weight dimers through gas-phase reactions of the stabilized Criegee Intermediate (sCI) formed from the ozonolysis of α-pinene. The high molecular weight and polar nature of dimers formed in the gas phase may explain increased particle number concentration as a result of homogenous nucleation. Since three of these dimers (i.e. pinyl-diaterpenyl dimer (MW 358), pinyl-diaterebyl dimer (MW 344) and pinonyl-pinyl dimer (MW 368)) have been observed in both laboratory-generated and ambient fine organic aerosol samples, we conclude that the dimers observed in this study can be used as tracers for the O3-initiated oxidation of α-pinene, and are therefore indicative of enhanced anthropogenic activities, and that the high molecular weight and low volatility dimers result in homogenous nucleation under laboratory conditions, increasing the particle number concentration.
In-cloud sulfate addition to single particles resolved with sulfur isotope analysis during HCCT-2010
Authors: Harris E. , Sinha B. , van Pinxteren D. , Schneider J. , Poulain L. , Collett J. , D'Anna B. , Fahlbusch B. , Foley S. , Fomba K. W. , George C. , Gnauk T. , Henning S. , Lee T. , Mertes S. , Roth A. , Stratmann F. , Borrmann S. , Hoppe P. , Herrmann H.
Published: April 2014

Abstract. In-cloud production of sulfate modifies aerosol size distribution, with important implications for the magnitude of indirect and direct aerosol cooling and the impact of SO2 emissions on the environment. We investigate which sulfate sources dominate the in-cloud addition of sulfate to different particle classes as an air parcel passes through an orographic cloud. Sulfate aerosol, SO2 and H2SO4 were collected upwind, in-cloud and downwind of an orographic cloud for three cloud measurement events during the Hill Cap Cloud Thuringia campaign in autumn 2010 (HCCT-2010). Combined SEM and NanoSIMS analysis of single particles allowed the δ34S of particulate sulfate to be resolved for particle size and type. The most important in-cloud SO2 oxidation pathway at HCCT-2010 was aqueous oxidation catalysed by transition metal ions (TMI catalysis), which was shown with single particle isotope analyses to occur primarily in cloud droplets nucleated on coarse mineral dust. In contrast, direct uptake of H2SO4 (g) and ultrafine particulate were the most important sources modifying fine mineral dust, increasing its hygroscopicity and facilitating activation. Sulfate addition to "mixed" particles (secondary organic and inorganic aerosol) and coated soot was dominated by in-cloud aqueous SO2 oxidation by H2O2 and direct uptake of H2SO4 (g) and ultrafine particle sulfate, depending on particle size mode and time of day. These results provide new insight into in-cloud sulfate production mechanisms, and show the importance of single particle measurements and models to accurately assess the environmental effects of cloud processing.
Snow cover sensitivity to black carbon deposition in the Himalayas: from atmospheric and ice core measurements to regional climate simulations
Authors: Ménégoz M. , Krinner G. , Balkanski Y. , Boucher O. , Cozic A. , Lim S. , Ginot P. , Laj P. , Gallée H. , Wagnon P. , Marinoni A. , Jacobi H. W.
Published: April 2014

Abstract. We applied a climate-chemistry global model to evaluate the impact of black carbon (BC) deposition on the Himalayan snow cover from 1998 to 2008. Using a stretched grid with a resolution of 50 km over this complex topography, the model reproduces reasonably well the remotely sensed observations of the snow cover duration. Similar to observations, modelled atmospheric BC concentrations in the central Himalayas reach a minimum during the monsoon and a maximum during the post- and pre-monsoon periods. Comparing the simulated BC concentrations in the snow with observations is more challenging because of their high spatial variability and complex vertical distribution. We simulated spring BC concentrations in surface snow varying from tens to hundreds of μg kg−1, higher by one to two orders of magnitude than those observed in ice cores extracted from central Himalayan glaciers at high elevations (>6000 m a.s.l.), but typical for seasonal snow cover sampled in middle elevation regions (<6000 m a.s.l.). In these areas, we estimate that both wet and dry BC depositions affect the Himalayan snow cover reducing its annual duration by 1 to 8 days. In our simulations, the effect of anthropogenic BC deposition on snow is quite low over the Tibetan Plateau because this area is only sparsely snow covered. However, the impact becomes larger along the entire Hindu-Kush, Karakorum and Himalayan mountain ranges. In these regions, BC in snow induces an increase of the net short-wave radiation at the surface with an annual mean of 1 to 3 W m−2 leading to a localised warming between 0.05 and 0.3 °C.
The effects of aerosols on water cloud microphysics and macrophysics based on satellite observations over East Asia and the North Pacific
Authors: Michibata T. , Kawamoto K. , Takemura T.
Published: April 2014

Abstract. This study examines the characteristics of the microphysics and macrophysics of water clouds from East Asia to the North Pacific, using data from satellite observations. Our goals are to clarify differences in microphysics and macrophysics between land and oceanic clouds, seasonal differences unique to the mid-latitudes, characteristics of the drizzling process, and cloud vertical structure. In pristine oceanic areas, fractional occurrences of cloud optical thickness (COT) and cloud droplet effective radius (CDR) increase systematically with an increase in drizzle intensity, but in polluted land areas these characteristics of the COT and CDR transition are not as evident. Additionally, regional and seasonal differences are identified in terms of drizzle intensity as a function of the liquid water path (LWP) and cloud droplet number concentration (Nc). The correlations between drizzle intensity and LWP, and between drizzle intensity and Nc are both more robust over oceanic areas than over land areas. We also demonstrate regional and seasonal characteristics of the cloud vertical structure. As a result, we find aerosol–cloud interaction mainly occurs around the cloud base in polluted land areas during the winter season. In addition, a difference between polluted and pristine areas in the efficiency of cloud droplet growth is confirmed. These results suggest that water clouds over the mid-latitudes exhibit a different drizzle system to those over the tropics.
Relating hygroscopicity and optical properties to chemical composition and structure of secondary organic aerosol particles generated from the ozonolysis of α-pinene
Authors: Denjean C. , Formenti P. , Picquet-Varrault B. , Pangui E. , Zapf P. , Katrib Y. , Giorio C. , Tapparo A. , Monod A. , Temime-Roussel B. , Decorse P. , Mangeney C. , Doussin J. F.
Published: April 2014

Abstract. Secondary Organic Aerosol (SOA) were generated from the ozonolysis of α-pinene in the CESAM simulation chamber. The formation and ageing of the SOA were studied by following their optical, hygroscopic and chemical properties. The optical properties investigated by determining the particle Complex Refractive Index (CRI). The hygroscopicity was quantified by measuring the effect of RH on particle size (Growth Factor, GF) and scattering coefficient (f(RH)). The oxygen to carbon (O : C) atomic ratio of the particle surface and bulk were used as a sensitive parameter to correlate the changes in hygroscopic and optical properties of the SOA composition in CESAM. The real CRI at 525 nm wavelength decreased from 1.43–1.60 (±0.02) to 1.32–1.38 (±0.02) during the SOA formation. The decrease in real CRI correlates with a decrease in the O : C ratio of SOA from 0.68 (±0.20) to 0.55 (±0.16). In contrast, the GF stayed roughly constant over the reaction time, with values of 1.02–1.07 (±0.02) at 90% (±4.2) RH. Simultaneous measurements of O : C ratio of the particle surface revealed that the SOA was not composed of a homogeneous mixture, but with less oxidised species at the surface which would limit the water adsorption onto particle. In addition, an apparent change of both mobility diameter and scattering coefficient with increasing RH from 0 to 30% was observed for SOA after 16 h reaction. We postulate that this change could be due to a change in the viscosity of the SOA from a predominantly glassy state to a predominantly liquid state.
Variability of the infrared complex refractive index of African mineral dust: experimental estimation and implications for radiative transfer and satellite remote sensing
Authors: Di Biagio C. , Boucher H. , Caquineau S. , Chevaillier S. , Cuesta J. , Formenti P.
Published: April 2014

Abstract. Experimental estimations of the infrared refractive index of African mineral dust have been retrieved from laboratory measurements of particle transmission spectra in the wavelength range 2.5–25 μm. Five dust samples collected at Banizoumbou (Niger) and Tamanrasset (Algeria) during dust events originated from different Western Saharan and Sahelian areas have been investigated. The obtained real (n) and imaginary (k) parts of the refractive index for the different dust cases vary in the range 1.1–2.7 and 0.05–1.0, respectively, and appear to be strongly sensitive to the mineralogical composition of the particles, especially in the 8–12 μm and 17–25 μm spectral intervals. Dust absorption is controlled mainly by clays, and, in minor fraction, by quartz and Ca-rich minerals. Size distribution, and the coarse fraction in particular, plays also a role in determining the refractive index. Significant differences are obtained when comparing our results with existing experimental estimations available in the literature, and with the values of the OPAC (Optical Properties of Aerosols and Clouds) database. The different datasets appear comparable in magnitude, with our values of n and k falling in the range of variability of past studies. However, literature data fail in accurately reproducing the spectral signatures of main minerals, in particular clays, and they significantly overestimate the contribution of quartz. We also found that the real and the imaginary parts of the refractive index from part of literature studies do not verify Kramers–Kronig relations, thus resulting theoretically incorrect. The comparison between our results, from Western Africa, and literature data, from different locations in Europe, Africa, and the Caribbean, nonetheless, confirms the expected large variability of the infrared refractive index of dust, thus highlighting the necessity for an extended systematic investigation. Aerosol intensive optical properties relevant to radiative transfer (mass extinction efficiency, kext, single scattering albedo, ω, and asymmetry factor, g), have been calculated, by using the Mie theory, for the five analysed dust samples, based on the estimated refractive index and measured particle size distribution. The optical properties show a large sample-to-sample variability. This variability is expected to significantly impact satellite retrievals of atmospheric and surface parameters and estimates of the dust radiative forcing.
A new inversion algorithm for backscatter ionogram and its experimental validation
Authors: Zhao J. J. , Zhou C. , Yang G. B. , Jiang C. H. , Chang S. S. , Zhu P. , Gu X. D. , Ni B. B. , Zhao Z. Y.
Published: April 2014

Abstract. Oblique backscatter sounding is a powerful tool for detecting and monitoring the ionosphere continuously at a remote distance. High-frequency (HF) backscatter ionograms provide the amplitudes of backscatter signals with respect to group path or time delay against operating frequency. Application of inversion algorithm to a backscatter ionogram can extract useful information regarding the ionospheric electron density along the propagation paths. The present study proposes a new inversion algorithm on basis of simulated annealing method to acquire the leading edge of sweep-frequency ionogram, which is subsequently validated by ionospheric vertical sounding data. Quantitative comparisons between the vertical sounding measurements and the inversion results obtained from oblique backscatter sounding indicate that the new algorithm enables us to overcome the instability issue that traditional inversion algorithm faces and output reliable information of ionospheric inversion with satisfactory efficiency, thus providing a robust alternative for ionospheric detection based on oblique backscatter ionograms especially when the ionosphere is calm with slow changes.
Stable isotopes dissect aquatic food webs from the top to the bottom
Authors: Middelburg J. J.
Published: April 2014

Abstract. Stable isotopes have been used extensively to study food-web functioning, that is, the flow of energy and matter among organisms. Traditional food-web studies are based on the natural variability of isotopes and are limited to larger organisms that can be physically separated from their environment. Recent developments allow isotope ratio measurements of microbes and this in turn allows the measurement of entire food webs, in other words, from small producers at the bottom to large consumers at the top. Here, I provide a concise review on the use and potential of stable isotopes to reconstruct end-to-end food webs. I will first discuss food web reconstruction based on natural abundances isotope data and will then show that the use of stable isotopes as deliberately added tracers provides complementary information. Finally, challenges and opportunities for end-to-end food web reconstructions in a changing world are discussed.
The temperature sensitivity of organic matter decay in tidal marshes
Authors: Kirwan M. L. , Guntenspergen G. R. , Langley J. A.
Published: April 2014

Abstract. Approximately half of marine carbon sequestration takes place in coastal wetlands, including tidal marshes, where ecosystems accumulate organic matter to build soil elevation and survive sea level rise. The long-term viability of marshes, and their carbon pools, depends in part on how the balance between productivity and decay responds to climate change. Here, we report the sensitivity of soil organic matter decay in tidal marshes to seasonal and latitudinal variations in temperature measured over a 3 year period. We find a moderate increase in decay rate at warmer temperatures (3–6% °C−1, Q10 = 1.3–1.5). Despite the profound differences between microbial metabolism in wetlands and uplands, our results indicate a strong conservation of temperature sensitivity. Moreover, simple comparisons with organic matter production suggest that elevated atmospheric CO2 and warmer temperatures will accelerate carbon accumulation in marsh soils, and enhance their ability to survive sea level rise.
Terrigenous input off northern South America driven by changes in Amazonian climate and the North Brazil Current retroflection during the last 250 ka
Authors: Govin A. , Chiessi C. M. , Zabel M. , Sawakuchi A. O. , Heslop D. , Hörner T. , Zhang Y. , Mulitza S.
Published: April 2014

Abstract. We investigate changes in the delivery and oceanic transport of Amazon sediments related to terrestrial climate variations over the last 250 ka. We present high-resolution geochemical records from four marine sediment cores located between 5 and 12° N along the northern South American margin. The Amazon River is the sole source of terrigenous material for sites at 5 and 9° N, while the core at 12° N receives a mixture of Amazon and Orinoco detrital particles. Using an endmember unmixing model, we estimated the relative proportions of Amazon Andean material ("%-Andes", at 5 and 9° N) and of Amazon material ("%-Amazon", at 12° N) within the terrigenous fraction. The %-Andes and %-Amazon records exhibit significant precessional variations over the last 250 ka that are more pronounced during interglacials in comparison to glacial periods. High %-Andes values observed during periods of high austral summer insolation reflect the increased delivery of suspended sediments by Andean tributaries and enhanced Amazonian precipitation, in agreement with western Amazonian speleothem records. Increased Amazonian rainfall reflects the intensification of the South American monsoon in response to enhanced land–ocean thermal gradient and moisture convergence. However, low %-Amazon values obtained at 12° N during the same periods seem to contradict the increased delivery of Amazon sediments. We propose that reorganizations in surface ocean currents modulate the northwestward transport of Amazon material. In agreement with published records, the seasonal North Brazil Current retroflection is intensified (or prolonged in duration) during cold substages of the last 250 ka (which correspond to intervals of high DJF or low JJA insolation) and deflects eastward the Amazon sediment and freshwater plume.
SST phases in the open-ocean and margins of the tropical Pacific; implication on tropical climate dynamics
Authors: Shiau L.-J. , Clemens S. C. , Chen M.-T. , Yamamoto M. , Yokoyama Y.
Published: April 2014

Abstract. The tropical Pacific exerts a major effect on the global climate system and might have driven large extra-tropical climate change. We present a 320 kyr high resolution UK'37-sea surface temperature (SST) record from core MD052928 (11°17.26' S, 148°51.60' E, water depth 2250 m) located off southeastern Papua New Guinea (PNG), in the western tropical Pacific. The age model of the core is based on AMS 14C dating of planktic foraminifers and correlation of benthic to the LR04 stack. The UK'37-SST ranges from 26.5 to 29 °C, showing glacial–interglacial and millennial variations. We assess the phase of the MD052928 UK'37-SST as part of a synthesis of five other SST records from the tropical Pacific at the precession, obliquity, and eccentricity bands. The SST records can be separated into two groups when considering SST phase relative to changes in orbital forcing, ice volume and greenhouse gases (GHGs). SST maxima at open-ocean sites within primary equatorial current systems occur between obliquity maxima and methane (CH4) maxima but early relative to ice volume minima and CO2 maxima at the obliquity band. In contrast, SST maxima at continental margin sites change are in phase with ice minima and CO2 maxima, likely influenced by the slow response of continental ice sheets and GHGs. At the precession band, the early group located on the Warm Pool area indicates a direct influenced by the local insolation, and with the similar phase progress as the obliquity band. These results indicate that the decreased high-low latitudes insolation gradient and increasing low latitude local insolation resulting in tropical Pacific SST rise. Higher SST would supply more moisture resulting in increased CH4 in the tropical wetlands. This promotes increasing CO2 and deglaciation leading to increase continental and continental margin surface temperatures.
Observations of a stratospheric aerosol veil from a tropical volcanic eruption in December 1808: is this the "Unknown" ~1809 eruption?
Authors: Guevara-Murua A. , Williams C. A. , Hendy E. J. , Rust A. C. , Cashman K. V.
Published: April 2014

Abstract. The "Unknown" eruption of 1808/1809 was the second most explosive SO2-rich volcanic eruption in the last two centuries, only eclipsed by the cataclysmic VEI 7 Tambora eruption in April 1815. However, no eyewitness accounts of the event, and therefore its location, or the atmospheric optical effects associated with its aerosols have been documented from historical records. Here we report on two meteorological observations dating from the end of 1808 that describe phenomena we attribute to volcanic-induced atmospheric effects caused by the Unknown eruption. The observations were made by two highly respected Latin American scientists. The first, Francisco José de Caldas, describes a stratospheric aerosol haze, a "transparent cloud that obstructs the sun's brilliance", that was visible over the city of Bogotá, Colombia, from 11 December 1808 to at least mid-February 1809. The second, made by physician José Hipólito Unanue in Lima, Peru, describes sunset after-glows (akin to well-documented examples known to be caused by stratospheric volcanic aerosols) from mid-December 1808 to February 1809. These two accounts provide direct evidence of a persistent stratospheric aerosol veil that spanned at least 2600 km into both Northern and Southern Hemispheres and establish that the source was a tropical volcano. Moreover, these observations confirm that the Unknown eruption, previously identified and tentatively assigned to February 1809 (±4 months) from analysis of ice core sulphate records, occurred in late November or early December 1808 (4 December 1808 ± 7 days). This date has important implications for the associated hemispheric climate impacts and temporal pattern of aerosol dispersal.
Ocean Biogeochemistry in the warm climate of the Late Paleocene
Authors: Heinze M. , Ilyina T.
Published: April 2014

Abstract. The Late Paleocene is characterized by warm and stable climatic conditions which served as the background climate for the Paleocene-Eocene Thermal Maximum (PETM, ~55 million years ago). With respect to feedback processes in the carbon cycle, the ocean biogeochemical background state is of major importance for projecting the climatic response to a carbon perturbation related to the PETM. Therefore we use the Hamburg Ocean Carbon Cycle model HAMOCC, embedded into the ocean general circulation model of the Max Planck Institute for Meteorology, MPIOM, to constrain the ocean biogeochemistry of the Late Paleocene. We focus on the evaluation of modeled spatial and vertical distributions of the ocean carbon cycle parameters in a long-term warm steady-state ocean, based on a 560 ppm CO2 atmosphere. Model results are discussed in the context of available proxy data and simulations of pre-industrial conditions. Our results illustrate that ocean biogeochemistry is shaped by the warm and sluggish ocean state of the Late Paleocene, which affects the strength and spatial variation of the different carbon pumps. Primary production is only slightly reduced in comparison to present-day; it is intensified along the equator, especially in the Atlantic. This enhances remineralization of organic matter, resulting in strong oxygen minimum zones and CaCO3 dissolution in intermediate waters. We show that an equilibrium CO2 exchange without increasing total alkalinity concentrations above today's values is achieved. Yet, the surface ocean pH and the saturation state with respect to CaCO3 are lower than today. Our results indicate that under such conditions, the surface ocean carbonate chemistry is expected to be more sensitive to a carbon perturbation (i.e. the PETM) due to lower CO32− concentration, whereas the deep ocean calcite sediments would be less vulnerable to dissolution due to the sluggish ocean.
A geomorphology based approach for digital elevation model fusion – case study in Danang City, Vietnam
Authors: Tran T. A. , Raghavan V. , Masumoto S. , Vinayaraj P. , Yonezawa G.
Published: April 2014

Abstract. Global Digital Elevation Model (DEM) is considered as vital spatial information and finds wide use in several applications. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global DEM (GDEM) and Shuttle Radar Topographic Mission (SRTM) DEM offer almost global coverage and provide elevation data for geospatial analysis. However, GDEM and SRTM still contain some height errors that affect the quality of elevation data significantly. This study aims to examine methods to improve the resolution as well as accuracy of available free DEMs by data fusion technique and evaluating the results with high quality reference DEM. The DEM fusion method is based on the accuracy assessment of each global DEM and geomorphological characteristics of the study area. Land cover units were also considered to correct the elevation of GDEM and SRTM with respect to the bare earth surface. Weighted averaging method was used to fuse the input DEMs based on landform classification map. According to the landform types, the different weights were used for GDEM and SRTM. Finally, a denoising algorithm (Sun et al., 2007) was applied to filter the output fused DEM. This fused DEM shows excellent correlation to the reference DEM having correlation coefficient R2 = 0.9986 and the accuracy was also improved from Root Mean Square Error (RMSE) 14.9 m in GDEM and 14.8 m in SRTM into 11.6 m in fused DEM.
Characterizing configurations of fire ignition points through spatiotemporal point processes
Authors: Comas C. , Costafreda-Aumedes S. , Vega-Garcia C.
Published: April 2014

Abstract. Human-caused forest fires are usually regarded as unpredictable but often exhibit trends towards clustering in certain locations and periods. Characterizing such configurations is crucial for understanding spatiotemporal fire dynamics and implementing preventive actions. Our objectives were to analyse the spatiotemporal point configuration and to test for spatiotemporal interaction. We characterized the spatiotemporal structure of 984 fire ignition points in a study area of Galicia, Spain, during 2007–2011 by the K-Ripley's function. Our results suggest the presence of spatiotemporal structures for time lags of less than two years and ignition point distances in the range 0–12 km. Ignition centre points at time lags of less than 100 days are aggregated for any inter-event distance. This cluster structure loses strength as the time lag increases, and at time lags of more than 365 days this cluster structure is not significant for any lag distance. Our results also suggest spatiotemporal interdependencies at time lags of less than 100 days and inter-event distances of less than 10 km. At time lags of up to 365 days spatiotemporal components are independent for any point distance. These results suggest that risk conditions occur locally and are short-lived in this study area.