bluuebunny/crossref_metadata_2025 huggingface dataset:
The added value of system robustness analysis for flood risk management
Authors: Mens M. J. P. , Klijn F.
Published: April 2014

Abstract. Decision makers in fluvial flood risk management increasingly acknowledge that they have to prepare for extreme events. Flood risk is the most common basis on which to compare flood risk-reducing strategies. To take uncertainties into account the criteria of robustness and flexibility are advocated as well. This paper discusses the added value of robustness as additional decision criterion compared to single-value flood risk only. We do so by quantifying flood risk and system robustness for alternative system configurations of the Ijssel River valley in the Netherlands. We found that robustness analysis has added value in three respects: (1) it does not require assumptions on current and future flood probabilities, since flood consequences are shown as a function of discharge, (2) it shows the sensitivity of the system to varying discharges and (3) it supports a discussion on the acceptability of flood damage. We conclude that robustness analysis is a valuable addition to flood risk analysis in support of long-term decision-making on flood risk management.
Empirical estimation of present-day Antarctic glacial isostatic adjustment and ice mass change
Authors: Gunter B. C. , Didova O. , Riva R. E. M. , Ligtenberg S. R. M. , Lenaerts J. T. M. , King M. A. , van den Broeke M. R. , Urban T.
Published: April 2014

Abstract. This study explores an approach that simultaneously estimates Antarctic mass balance and glacial isostatic adjustment (GIA) through the combination of satellite gravity and altimetry data sets. The results improve upon previous efforts by incorporating a firn densification model to account for firn compaction and surface processes as well as reprocessed data sets over a slightly longer period of time. A range of different Gravity Recovery and Climate Experiment (GRACE) gravity models were evaluated and a new Ice, Cloud, and Land Elevation Satellite (ICESat) surface height trend map computed using an overlapping footprint approach. When the GIA models created from the combination approach were compared to in situ GPS ground station displacements, the vertical rates estimated showed consistently better agreement than recent conventional GIA models. The new empirically derived GIA rates suggest the presence of strong uplift in the Amundsen Sea sector in West Antarctica (WA) and the Philippi/Denman sectors, as well as subsidence in large parts of East Antarctica (EA). The total GIA-related mass change estimates for the entire Antarctic ice sheet ranged from 53 to 103 Gt yr−1, depending on the GRACE solution used, with an estimated uncertainty of ±40 Gt yr−1. Over the time frame February 2003–October 2009, the corresponding ice mass change showed an average value of −100 ± 44 Gt yr−1 (EA: 5 ± 38, WA: −105 ± 22), consistent with other recent estimates in the literature, with regional mass loss mostly concentrated in WA. The refined approach presented in this study shows the contribution that such data combinations can make towards improving estimates of present-day GIA and ice mass change, particularly with respect to determining more reliable uncertainties.
The Wheat Aquaporin Gene TaAQP7 Confers Tolerance to Cold Stress in Transgenic Tobacco
Authors: Huang Chao , Zhou Shiyi , Hu Wei , Deng Xiaomin , Wei Shuya , Yang Guangxiao , He Guangyuan
Published: April 2014

Aquaporin proteins (AQPs) have been shown to be involved in abiotic stress responses. However, the precise role of AQPs, especially in response to cold stress, is not understood in wheat (Triticum aestivum). In the present study, quantitative real time polymerase chain reaction (qRT-PCR) analysis revealed that TaAQP7 expression increased in leaves, but decreased in roots after cold treatment. Expression of TaAQP7 in tobacco plants resulted in increased root elongation and better growth compared with wild-type (WT) plants under cold stress. Moreover, after cold treatment, the transgenic tobacco lines exhibited higher chlorophyll contents, lower levels of malondialdehyde (MDA), and less ion leakage (IL) than WT plants. Thus, expression of TaAQP7 enhanced cold stress tolerance in transgenic tobacco. Taken together, our results suggest that TaAQP7 confers cold stress tolerance by relieving membrane damage in the transgenic plants.
The Co-Occurrence of Two Pyridine Alkaloids, Mimosine and Trigonelline, in Leucaena leucocephala
Authors: Ogita Shinjiro , Kato Misako , Watanabe Shin , Ashihara Hiroshi
Published: April 2014

Leucaena leucocephala is a nitrogen-fixing tropical leguminous tree that produces two pyridine alkaloids, i. e. mimosine [β-(3-hydroxy-4-pyridon-1-yl)-L-alanine] and trigonelline (1- methylpyridinium-3-carboxylate). Mimosine has been detected in leaves, flowers, pods, seeds, and roots, and it is one of the principal non-protein amino acids that occurs in all organs. Asparagine was the most abundant amino acid in flowers. The mimosine content varied from 3.3 μmol/g fresh weight (FW) in developing flowers to 171 μmol/g FW in mature seeds. Trigonelline was also detected in leaves, flowers, pods, and seeds, but not roots. The trigonelline content was lower than that of mimosine in all organs. It varied from 0.12 μmol/g FW in developing seeds to 2.6 μmol/g FW in mature seeds. [2-14C]Nicotinic acid supplied to the developing seeds was incorporated into trigonelline but not mimosine. This indicates that the pyridine and dihydroxypyridine structures of these two alkaloids are derived from distinct precursors. The physiological functions of mimosine and trigonelline are discussed briefly.
The Case for Integrating Accounting, Finance, and Economics in Teaching the GFC Through a Problem-Based Learning Approach
Authors: Guest Ross ,   Neilson Journals Publishing
Published: April 2014

This paper argues that a key lesson of the GFC of 2008-9 is that our “silo” approach to the disciplines of accounting, finance, and economics (AFE) has not equipped students to deal with complex real world problems such as global financial crises. Such real world problems are interdisciplinary in their causes, effects, and solutions. The paper discusses elements of each of the AFE disciplines that are essential for understanding the GFC, and why courses in economics and finance that seek to address the GFC as a topic need to integrate ideas from these three disciplines. A problem-based learning (PBL) approach is offered as a way forward, through at least one capstone course in a business/commerce degree that brings together the strands from a range of commerce/business disciplines in a case study approach. The paper offers an outline of such a PBL approach to the GFC.
Money Mathematics: Examining Ethics Education in Quantitative Finance
Authors: West Jason ,   Neilson Journals Publishing
Published: April 2014

The field of quantitative analysis is often mistaken to be a discipline free from ethical burdens. The quantitative financial analyst or “quant” profession holds a position of significant responsibility as the keeper of mathematical models used in complex derivative security pricing and risk management. Despite this responsibility very few postgraduate programs address the teaching of ethics and professional standards in their curriculum, and the credibility of the profession has suffered as a result of several high-profile financial losses. Some of these failures could have been avoided and their impacts diminished if ethical considerations were integrated with quantitative method. Appropriate development in ethics education for quants is needed to identify points in the decision-making process where ethical questions can arise, and to explain how quants can protect stakeholders from the costs of unethical behaviour. An approach to ethics education needs to be flexible and allow for different methods to infuse ethical coverage into the course. Such an approach will go some way towards aligning the profession with other specialisations in banking and avoid the need for complex and unnecessary regulation.
Teaching Finance in the Post-GFC Environment: Quomodo hic habetur, et Quo hinc?
Authors: Copp Richard I. ,   Neilson Journals Publishing
Published: April 2014

Despite criticism in the wake of the GFC, history shows that theory and curricula adapt to rectify any disconnects between theory, curricula, and practice. Finance theory unquestionably has antecedents in economics, accounting, legal theory, and psychology. Some theoretical developments—including the moral hazard consequences of limited liability—have yet to filter through to many texts and curricula, which also omit explanations of uncertainty; incomplete and (sub)optimal contracting; contagion; and behavioural finance. Student learning outcomes could be enhanced if universities, perhaps in a final year, cross-disciplinary “capstone” course, empowered students to understand the financial documentation evidencing sophisticated transactions; map relevant cash flows and wealth transfers; and recognise Ponzi schemes, the ethics of stakeholder wealth transfers, the conditions for contagion, and incentives for adverse selection and moral hazard in practice.
Simulated Trading Environment as a Learning Tool in Corporate Finance
Authors: Murgulov Zoltan ,   Neilson Journals Publishing
Published: April 2014

This research explores the application of an innovative learning approach by using trading simulation tutorials to reinforce the conventional learning styles in a corporate finance subject at postgraduate level. The majority of surveyed students perceive that their learning experience has been significantly enhanced through simulated trading tutorials. The post-trading survey shows students also indicate feeling more confident to self-monitor their learning. Furthermore, themajority of students feel able to recognise ethical issues in relation to trading in securities. This research highlights some potentially negative effects if trading simulations were to be used in isolation without providing students with a solid background in ethics. This issue is even more relevant in the post Global Financial Crisis environment. If carefully designed and implemented, trading simulations have a potential to mitigate some potentially negative effects of the use of technology and be an effective and inclusive teaching tool.
Past, Present, and Future: The Role of Tertiary Education in Supporting the Development of the Financial Planning Profession
Authors: Brimble Mark , Murphy Brian ,   Neilson Journals Publishing
Published: April 2014

The importance of financial advice for individuals is difficult to refute, however the degree to which the financial planning industry has been able to provide this to date is in debate. As a result, the industry, which is still in its infancy, has been subject to rapid growth, various controversies and regulatory intervention. The Global Financial Crisis (GFC) has contributed to the pace of this change with increased client, regulatory and self scrutiny as a result of the heightened dissatisfaction with advice outcomes. The coalescence of these factors has led to significant internal and external changes within the industry, resulting in the apparent commitment to becoming a profession. This paper will examine the implication of this agenda for tertiary education in relation to the role it could play to support the development of the financial planning profession. The paper achieves this by (1) reviewing the background to the financial planning industry and the move towards professionalism; (2) discussing current developments in the industry; (3) establishing the role of tertiary education and (4) assessing the role that tertiary education has played in supporting the financial planning sector. We argue that tertiary education has a critical role to play, however it is yet to achieve this. This study will be useful for those in both the managerial and operational/ academic elements of tertiary education in terms of providing considered avenues for engagement in this discipline. Indeed, if the paper provokes debate and discussion in tertiary education around the nation then we would consider our task complete.
Modelling Free Flow Speed on Two-Lane Rural Highways in Bosnia and Herzegovina
Authors: Lovrić Ivan , Cvitanić Dražen , Breški Deana
Published: April 2014

Free flow speed is used as a parameter in transportation planning and capacity analysis models, as well as speed-flow diagrams. Many of these models suggest estimating free flow speed according to measurements from similar highways, which is not a practical method for use in B&H. This paper first discusses problems with using these methodologies in conditions prevailing in B&H and then presents a free flow speed evaluation model developed from a comprehensive field survey conducted on nine homogeneous sections of state and regional roads.
Using Potential Accessibility Measure for Urban Public Transportation Planning: A Case Study of Denizli, Turkey
Authors: Gulhan Gorkem , Ceylan Huseyin , Baskan Ozgur , Ceylan Halim
Published: April 2014

Policy makers and planners evaluate the implementation of the urban public transport (UPT) planning studies in terms of some objective measures such as load factor, mean volume per trip, capacity usage ratio and total capacity. In some cases, improving these measures may lead an unforeseen decrease on accessibility to the opportunities in terms of UPT users. Thus, this study aims to evaluate Potential Accessibility (PA) as an efficiency measure in decision stage of UPT planning. It widely depends on fieldwork, surveys, data inventories and existing plans. In this context, a comprehensive UPT planning has been carried out through VISUM traffic simulation software by taking the PA into account, and a four-step UPT planning procedure has been proposed. The results showed that PA may alternatively be used as an evaluation instrument in decision stage of UPT planning while the objective measures are insufficient to represent the effectiveness of alternative scenarios.
Comparative Analysis of Safety Performance Indicators Based on Inductive Loop Detector Data
Authors: Mamdoohi Amir Reza , Fallah Zavareh Mohsen , Hydén Christer , Nordfjærn Trond
Published: April 2014

Conflicts in traffic stream have been detected by different safety performance indicators. This study aims to empirically investigate the differences between different indicators in detecting rear-end conflicts and assessing the risk in an uninterrupted flow. Micro-level data of a 24-hr traffic stream (including 6,657 vehicles) were captured using inductive loop detectors installed on a rural freeway section. Different indicators (Time Headway (H), Time to Collision (TTC), Proportion of Stopping Distance (PSD), Deceleration Rate to Avoid Collision (DRAC) and Stopping Distance Index (SDI)) were used to measure each car following event in a bivalent state (safe/unsafe). Unsafe events associated with each indicator were detected and common unsafe events characterized by different indicators were identified. Temporal distributions of rear-end collision risks associated with each indicator at 15-min intervals were also compared. Finally, the 15-min risk values based on different indicators were categorized and compared across three levels (Low, Medium and High). Data mining and statistical techniques showed that while SDI is the single most conservative indicator, DRAC and TTC detect a few risky events but very equal ones. In almost all conflicts associated with TTC, headway is still lower than the critical threshold. However, there exist considerable risky events based on headway which are still safe according to TTC. Comparison of PSD and TTC also declares that almost all conflicts associated with TTC are also risky according to PSD.
Effectiveness of Newly Introduced Variable Message Signs in Al-Khobar, Saudi Arabia
Authors: Ratrout Nedal Taisir , Issa Yazan F
Published: April 2014

Recently, Variable Message Signs (VMS) were introduced in Saudi Arabia and their reliability under local environment is being tested. This paper aims to evaluate the possible response of the drivers to VMS when used for messages related to traffic conditions. A major arterial in Al-Khobar city in Saudi Arabia with a massive VMS board was selected for this paper. The evaluation process started by interviewing drivers selected randomly from the study area. About 77% of the interviewed drivers indicated positive attitude toward messages requesting change of route. The drivers’ interviews demonstrated statistical relationship between the degree of response to messages requesting change of route and the reason for such request. The maximum response was for messages related to accidents, roadwork activities, and traffic congestion. A field experiment was also conducted along the studied arterial. It was found that VMS statistically increased the percentage of diverted traffic during specific peak periods.
Correlation between Land Use and Urban Public Transport: Case Study of Zagreb
Authors: Štefančić Gordana , Šarić Slavko , Spudić Robert
Published: April 2014

Investment in the transport system with the aim of fostering attractiveness and land use in urban structures is of great interest for planners and investors. Investment in urban public transport would especially contribute to revitalising distinct city areas. The samples of high population density and diversified area use are organised around accessible means of urban public transport.The main objective of this case study was to find an adequate model for the solution of urban public transport on the location Novi Jelkovec in Zagreb after the construction of a new urban settlement, with the aim to revitalise the peripheral parts of the city. The theoretical assumption on the influence of better organised transport on land use is hereby researched through the example of correction of timetables and reduction of travelling time between nodes on the line in the Novi Jelkovec settlement. In preparing this paper the following methods were used: analysis and synthesis, mathematical and statistical methods, methods of interviewing. The theory of correlation of land use and urban public transport is based on models that develop the “compact city”. The obtained research results confirm the significance of the correlation between urban land use and urban public transport. It can be concluded that this paper proves the influence of the correlation between land use and urban public transport on the concrete example of Novi Jelkovec. Its implementation could result in solving the concrete traffic problem and along with it a faster urbanisation of the new settlement.
A three‐tier framework for monitoring antiretroviral therapy in high HIV burden settings
Authors: Osler Meg , Hilderbrand Katherine , Hennessey Claudine , Arendse Juanita , Goemaere Eric , Ford Nathan , Boulle Andrew
Published: April 2014

The provision of antiretroviral therapy (ART) in low and middle‐income countries is a chronic disease intervention of unprecedented magnitude and is the dominant health systems challenge for high‐burden countries, many of which rank among the poorest in the world. Substantial external investment, together with the requirement for service evolution to adapt to changing needs, including the constant shift to earlier ART initiation, makes outcome monitoring and reporting particularly important. However, there is growing concern at the inability of many high‐burden countries to report on the outcomes of patients who have been in care for various durations, or even the number of patients in care at a particular point in time. In many instances, countries can only report on the number of patients ever started on ART. Despite paper register systems coming under increasing strain, the evolution from paper directly to complex electronic medical record solutions is not viable in many contexts. Implementing a bridging solution, such as a simple offline electronic version of the paper register, can be a pragmatic alternative. This paper describes and recommends a three‐tiered monitoring approach in low‐ and middle‐income countries based on the experience implementing such a system in the Western Cape province of South Africa. A three‐tier approach allows Ministries of Health to strategically implement one of the tiers in each facility offering ART services. Each tier produces the same nationally required monthly enrolment and quarterly cohort reports so that outputs from the three tiers can be aggregated into a single database at any level of the health system. The choice of tier is based on context and resources at the time of implementation. As resources and infrastructure improve, more facilities will transition to the next highest and more technologically sophisticated tier. Implementing a three‐tier monitoring system at country level for pre‐antiretroviral wellness, ART, tuberculosis and mother and child health services can be an efficient approach to ensuring system‐wide harmonization and accurate monitoring of services, including long term retention in care, during the scale‐up of electronic monitoring solutions.
Seletividade de herbicidas aplicados com óleo mineral na cultura da mandioca ‘Cascuda’
Authors: Costa Neumarcio Vilanova , Pavan Guilherme Cardoso , Dourado Rodrigo Fernando , Costa Andreia Cristina Peres Rodrigues da , Vasconcelos Edmar Soares
Published: April 2014

O uso de adjuvante pode influenciar na seletividade dos herbicidas as culturas agrícolas. Objetivou-se avaliar a seletividade de herbicidas aplicados com diferentes concentrações de adjuvante óleo mineral na cultura da mandioca ‘Cascuda’. O delineamento experimental utilizado foi o de blocos ao acaso, com quatro repetições. Foi utilizado o esquema fatorial 3x3+1 que consistiu de três herbicidas clethodim (120 g ha-1); fluazifop-p-butyl (250 g ha-1) e mesotrione (240 g ha-1), três concentrações de óleo mineral (Assist®) 0,0; 0,5 e 1,0% v v-1; além de uma testemunha sem aplicação. Todas as parcelas foram mantidas livres da interferência das plantas daninhas por meio de capinas manuais. Apenas, o mesotrione promoveu sintomas de fitointoxicação leves a moderados (5,5 a 51,3%) quando aplicado com óleo mineral. Contudo, todos os herbicidas apresentaram-se seletivos à mandioca ‘Cascuda’ na dose aplicada, tanto na presença quanto ausência de óleo mineral até 1% v v-1.
Variations of the 3‐D coronal magnetic field associated with the X3.4‐class solar flare event of AR 10930
Authors: He Han , Wang Huaning , Yan Yihua , Chen P. F. , Fang Cheng
Published: April 2014

The variations of the 3‐D coronal magnetic fields associated with the X3.4‐class flare of active region 10930 are studied in this paper. The coronal magnetic field data are reconstructed from the photospheric vector magnetograms obtained by the Hinode satellite and using the nonlinear force‐free field extrapolation method developed in our previous work (He et al., 2011). The 3‐D force‐free factor α, 3‐D current density, and 3‐D magnetic energy density are employed to analyze the coronal data. The distributions of α and current density reveal a prominent magnetic connectivity with strong negative α values and strong current density before the flare. This magnetic connectivity extends along the main polarity inversion line and is found to be totally broken after the flare. The distribution variation of magnetic energy density reveals the redistribution of magnetic energy before and after the flare. In the lower space of the modeling volume the increase of magnetic energy dominates, and in the higher space the decrease of energy dominates. The comparison with the flare onset imaging observation exhibits that the breaking site of the magnetic connectivity and site with the highest values of energy density increase coincide with the location of flare initial eruption. We conclude that a cramped positive α region appearing in the photosphere causes the breaking of the magnetic connectivity. A scenario for flare initial eruption is proposed in which the Lorentz force acting on the isolated electric current at the magnetic connectivity breaking site lifts the associated plasmas and causes the initial ejection.
Moisture recycling in the Iberian Peninsula from a regional climate simulation: Spatiotemporal analysis and impact on the precipitation regime
Authors: Rios‐Entenza Alexandre , Soares Pedro M. M. , Trigo Ricardo M. , Cardoso Rita M. , Miguez‐Macho Gonzalo
Published: April 2014

The contribution of the evapotranspiration from a certain region to the precipitation over the same area is referred to as water recycling. In this paper, we explore the spatiotemporal links between the recycling mechanism and the Iberian rainfall regime. We use a 9 km resolution Weather Research and Forecasting simulation of 18 years (1990–2007) to compute local and regional recycling ratios over Iberia, at the monthly scale, through both an analytical and a numerical recycling model. In contrast to coastal areas, the interior of Iberia experiences a relative maximum of precipitation in spring, suggesting a prominent role of land‐atmosphere interactions on the inland precipitation regime during this period of the year. Local recycling ratios are the highest in spring and early summer, coinciding with those areas where this spring peak of rainfall represents the absolute maximum in the annual cycle. This confirms that recycling processes are crucial to explain the Iberian spring precipitation, particularly over the eastern and northeastern sectors. Average monthly recycling values range from 0.04 in December to 0.14 in June according to the numerical model and from 0.03 in December to 0.07 in May according to the analytical procedure. Our analysis shows that the highest values of recycling are limited by the coexistence of two necessary mechanisms: (1) the availability of sufficient soil moisture and (2) the occurrence of appropriate synoptic configurations favoring the development of convective regimes. The analyzed surplus of rainfall in spring has a critical impact on agriculture over large semiarid regions of the interior of Iberia.
Parameter optimization, sensitivity, and uncertainty analysis of an ecosystem model at a forest flux tower site in the United States
Authors: Wu Yiping , Liu Shuguang , Huang Zhihong , Yan Wende
Published: April 2014

Ecosystem models are useful tools for understanding ecological processes and for sustainable management of resources. In biogeochemical field, numerical models have been widely used for investigating carbon dynamics under global changes from site to regional and global scales. However, it is still challenging to optimize parameters and estimate parameterization uncertainty for complex process‐based models such as the Erosion Deposition Carbon Model (EDCM), a modified version of CENTURY, that consider carbon, water, and nutrient cycles of ecosystems. This study was designed to conduct the parameter identifiability, optimization, sensitivity, and uncertainty analysis of EDCM using our developed EDCM‐Auto, which incorporated a comprehensive R package—Flexible Modeling Framework (FME) and the Shuffled Complex Evolution (SCE) algorithm. Using a forest flux tower site as a case study, we implemented a comprehensive modeling analysis involving nine parameters and four target variables (carbon and water fluxes) with their corresponding measurements based on the eddy covariance technique. The local sensitivity analysis shows that the plant production‐related parameters (e.g., PPDF1 and PRDX) are most sensitive to the model cost function. Both SCE and FME are comparable and performed well in deriving the optimal parameter set with satisfactory simulations of target variables. Global sensitivity and uncertainty analysis indicate that the parameter uncertainty and the resulting output uncertainty can be quantified, and that the magnitude of parameter‐uncertainty effects depends on variables and seasons. This study also demonstrates that using the cutting‐edge R functions such as FME can be feasible and attractive for conducting comprehensive parameter analysis for ecosystem modeling.
Natural biogeochemical cycle of mercury in a global three‐dimensional ocean tracer model
Authors: Zhang Yanxu , Jaeglé Lyatt , Thompson LuAnne
Published: April 2014

We implement mercury (Hg) biogeochemistry in the offline global 3‐D ocean tracer model (OFFTRAC) to investigate the natural Hg cycle, prior to any anthropogenic input. The simulation includes three Hg tracers: dissolved elemental (Hg0aq), dissolved divalent (HgIIaq), and particle‐bound mercury (HgPaq). Our Hg parameterization takes into account redox chemistry in ocean waters, air‐sea exchange of Hg0, scavenging of HgIIaq onto sinking particles, and resupply of HgIIaq at depth by remineralization of sinking particles. Atmospheric boundary conditions are provided by a global simulation of the natural atmospheric Hg cycle in the GEOS‐Chem model. In the surface ocean, the OFFTRAC model predicts global mean concentrations of 0.16 pM for total Hg, partitioned as 80% HgIIaq, 14% Hg0aq, and 6% HgPaq. Total Hg concentrations increase to 0.38 pM in the thermocline/intermediate waters (between the mixed layer and 1000 m depth) and 0.82 pM in deep waters (below 1000 m), reflecting removal of Hg from the surface to the subsurface ocean by particle sinking followed by remineralization at depth. Our model predicts that Hg concentrations in the deep North Pacific Ocean (>2000 m) are a factor of 2–3 higher than in the deep North Atlantic Ocean. This is the result of cumulative input of Hg from particle remineralization as deep waters transit from the North Atlantic to the North Pacific on their ~2000 year journey. The model is able to reproduce the relatively uniform concentrations of total Hg observed in the old deep waters of the North Pacific Ocean (observations: 1.2 ± 0.4 pM; model: 1.1 ± 0.04 pM) and Southern Ocean (observations: 1.1 ± 0.2 pM; model: 0.8 ± 0.02 pM). However, the modeled concentrations are factors of 5–6 too low compared to observed concentrations in the surface ocean and in the young water masses of the deep North Atlantic Ocean. This large underestimate for these regions implies a factor of 5–6 anthropogenic enhancement in Hg concentrations.
Biomimetic Metal Phenolates
Authors: Tamasi Gabriella , Cini Renzo
Published: April 2014

The chapter reports on recent studies of metal complexes that have the phenolate group as a ligand. The synthesis and characterization of many low molecular weight complexes is reviewed and commented on. Special attention is devoted to biomimetic models, for a deeper understanding of metalloprotein structures and functions. The chapter is divided into two parts, related to oxidant and antioxidant activities and to the hydrolysis of phospatediesters, respectively.

Activity of phenols as antioxidants and VIVO2+, MnII, MnIII, MnIV,CoII, CoIII, NiII, CuI, CuIIand ZnIIcomplexes with phenolato‐containing Schiff bases as biomimetic for biological systems, is the focus of the first part. A section is dedicated to selected CuIIand PtIIcomplexes having pharmaceutical active molecules as ligands, from the OXICAM family of non‐steroidal anti‐inflammatory drugs. The second part reports on metal–phenolato complexes as models for phosphodiesterase enzymes. Dinuclear complexes based on ZnII, FeIII/ZnII, ZnII/MgIImetal centers are reviewed and commented on
Organic Compounds Containing Bonds between Se or Te with P, As, Sb and Bi
Authors: Murai Toshiaki
Published: April 2014

This chapter describes syntheses, structures, and reactions of the compounds with phosphorus‐selenium double bonds and with at least one carbon‐phosphorus single bond and of their heavier congeners. Among them, phosphane selenides have been the most deeply studied and used as Lewis base catalysts, metal ligands, molecular sensors, and stating materials leading to selenium‐containing nanoparticles. The coupling constants between the phosphorus and selenium atoms are informative on the basicity of the phosphanes. Phosphinoselenoic acid chlorides and secondary phosphanes are frequently used precursors to give a range of phosphinoselenoic acid derivatives, whereas selenation of dichlorophosphanes leads to phosphonoselenoic acid dichlorides, which are converted to a variety of acid derivatives. The selenation of phosphinites also gives phosphinoselenoic acidO‐esters. Stereochemical course of the substitution reaction atP‐chiral phosphorus center in the substitution reaction has been elucidated. Some reactions of dimers of diselenoxophosphanes such as Woollin's reagent are also shown. The chapter finally describes examples of phosphane tellurides, arsenic, antimony, and bismuth isologues of phosphane selenides, although these are fewer.
Coordination Chemistry of Organoselenium and Organotellurium Compounds
Authors: Mutoh Yuichiro
Published: April 2014

Selenolato and tellurolato complexes of metals as well as metal complexes with selenoether and telluroether ligands have been extensively studied for a long time and periodically reviewed with relevance to transition‐metal‐catalyzed reactions. However, only sporadically are papers available for the coordination chemistry of carbon‐selenium and carbon‐tellurium multiple‐bond molecules as supporting ligands for transition metals. Consequently, this chapter highlights the developments in fundamental coordination chemistry of group 6–10 transition metals having such relatively ignored organo‐selenium and ‐tellurium compounds as ligands; the simplest organo‐selenium and ‐tellurium species, that is, seleno‐ and tellurocarbonyl (carbon monoselenide, CSe and carbon monotelluride, CTe), which are heavier analogs of carbonyl (carbon monooxide, CO) ligand, and seleno‐ and tellurocarbonyl compounds (>C=Se and >C=Te).
Synthesis of Biologically Relevant Small Molecules Containing Selenium. Part B. Anti‐infective and Anticancer Compounds
Authors: Braga Antonio L. , Rafique Jamal
Published: April 2014

In the 19705 many reports described the identification of various selenoproteins, which are involved in a wide variety of biological processes, including antioxidant defense, thyroid hormone production and immune response. This brought a new dimension to the design and synthesis of organoselenium compounds as bioactive structures. In this chapter, strategies and methods for the preparation of anti‐infective, chemopreventive as well as anticancer compounds are reviewed. The unique redox properties of selenium confer catalytic activity to organoselenium compounds and influence their biological propert ies as well as the methods selected for their preparation. Several approaches can be applied In order to obtain organoselenium compounds, such as reaction of elemental selenium or diselenides with different types of carbon nucleophiles or reaction of organic electrophiles with selenolate anions generated by different methods, as discussed herein.
Reactions of Metal Complexes with Singlet Oxygen
Authors: Selke Matthias
Published: April 2014

A variety of reactions of metal complexes with singlet oxygen have been reported during the past several decades. These reactions can be divided into two parts, that is, reactions of the metal center and ligand oxidations. Reactions at the metal center involve physical deactivation of singlet oxygen and oxidative addition to form metal‐dioxygen complexes. These peroxo complexes may undergo insertion reactions or lose the added dioxygen molecule either in the singlet or triplet state. Reaction of some metal centers with hydrogen peroxide may also lead to formation of singlet oxygen which constitutes a dark (non‐photochemical) method of
1
O
2
generation. Olefinic ligands bound to Sn, Si, and W centers undergo singlet oxygen ene reactions, leading to conventional H‐ene products and/or peroxides bound to the metal atom (metallo‐ene reaction). These peroxides may be useful synthons for further transformations. Examples of [2+2] and [4+2] cycloaddition of singlet oxygen to ligands are also discussed. Finally, singlet oxygen reacts with metal‐bound thiolates and dithiolates, leading to formation of a variety of oxidized sulfur ligands, such as sulfenates and sulfinates. The mechanisms of these reactions appear to be somewhat similar to that of the photooxidation of organic sulfides but many details are poorly understood at this time.
Electrostatic Accelerators
Authors: Weisser David C.
Published: April 2014

We review the types of electrostatic accelerators currently in use and their historical antecedents. Applications enrich many areas of modern research especially in material analysis and modification. The rapidly developing scope of accelerator mass spectrometry, AMS, has given birth to new low energy accelerators and revitalized the appreciation of the enabling physics of the electron stripping process. Another exciting development has been in the simultaneous bombardment by several accelerators to simulate the radiation environment of nuclear reactors. This exploits a wide variety of accelerators and diagnostic techniques. High energy electrostatic accelerators are being eclipsed as injectors to booster accelerators by dedicated positive ion injectors. Nevertheless, electrostatic accelerators continue to be the bedrock for most injector laboratories during the often extended transition to positive ion injectors. They also continue in their historic role as workhorses of nuclear structure physics.
Nuclear γ‐Spectroscopy and the γ‐Spheres
Authors: Riley Mark , Simpson John
Published: April 2014

High‐resolution γ‐ray spectroscopy is one of the most powerful tools to study the structure of atomic nuclei. Significant advances in the development of increasingly sensitive instrumentation have taken place in recent decades. The latest 4π γ‐ray arrays, or “γ‐spheres,” continue to reveal fascinating new scientific phenomena at the limits of isospin, excitation energy, angular momentum, temperature, and charge. Another huge leap forward in the resolving power of
Ge
‐based detection systems is now taking place via the development of γ‐ray tracking arrays, which, when combined with new accelerator developments, assures a most exciting future to this field. These technical advances also have a wide range of application spin‐offs.
Physics of the Neutron
Authors: Schreckenbach Klaus
Published: April 2014

The nuclear and particle physics of the free neutron is described for neutron energies in the range of nanoelectronvolts to megaelectronvolts. The interaction of the neutron with the atomic nucleus, which comprises scattering and absorption, and the reaction mechanism are discussed, including parity nonconserving processes. In neutron particle physics, the progress in neutron sources and neutron beams has yielded experimental results for sensitive tests of the standard model in particle physics and beyond and some key experiments are presented.
Comparative performance of philic and phobic oil‐mist filters
Authors: Mullins Benjamin J. , Mead‐Hunter Ryan , Pitta Renato N. , Kasper Gerhard , Heikamp Wolfgang
Published: April 2014

The evolution of pressure drop, drainage rate, saturation, and efficiency of combined philic, and phobic oil mist filters in real‐time are examined. The experiments used four different filter configurations, with a combination of oleophobic and oleophilic fibrous filter media, and one oleophilic only reference. The effect of separating filter materials of differing wettability, with a mesh, was also explored. It was found that inclusion of a mesh between layers promoted increased drainage rates and resulted in a significantly lower pressure drop across the filter. The overall mass‐based filtration efficiency was also slightly higher for the configurations containing the mesh. Conversely, re‐entrainment of droplets from the rear face of the filter was only observed in filter configurations without the central mesh. Filters with oleophobic initial layers did not display a classical “depth filtration” pressure drop curve. The oleophobic media was found to possess lower steady‐state saturation than oleophilic media. Additionally, the steady‐state saturation of the oleophilic filter media, when placed at the rear of the filter, was lower when the central mesh was present. The saturation values were compared with recently published theory. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2976–2984, 2014
Mechanical stability of monolithic catalysts: Factors affecting washcoat adhesion and cohesion during preparation
Authors: Wu Dongfang , Kong Shangshang , Zhang Hua , Li Yongdan
Published: April 2014

Alumina‐washcoated cordierite monoliths are prepared to investigate the effects of the preparation process factors on the mechanical stability of monolithic catalysts. It is shown that the agent for pretreating substrates, properties of the washcoating solution (solid content, additive, and amount of additive), and washcoating times all have great effects on the washcoat loading and on the washcoat adhesion and cohesion. There is a great possibility of improving the mechanical stability through the optimization of these factors. If multiple washcoating is performed, the two‐time washcoating after calcination is recommended in this case. It is also pointed out that the minor variation of the washcoat loading with monolithic mini‐specimen increases the scatter of the washcoat adhesion and cohesion, resulting from fatigue failure of active material. Furthermore, the previously proposed mechanical failure mechanism is confirmed to be an effective tool to factors analysis of the mechanical stability of cordierite monolithic catalysts. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2765–2773, 2014
Modeling and Bayesian parameter estimation for semibatch pH‐shift reactive crystallization of l‐glutamic acid
Authors: Su Qing‐Lin , Chiu Min‐Sen , Braatz Richard D.
Published: April 2014

A mathematical model for semibatch pH‐shift reactive crystallization of l‐glutamic acid is developed that takes into account the effects of protonation and deprotonation in the species balance of glutamic acid, crystal size distribution, polymorphic crystallization, and nonideal solution properties. The crystallization mechanisms of  α‐ and β‐forms of glutamic acid are addressed by considering primary and secondary nucleation, size‐dependent growth rate, and mixing effects on nucleation. The kinetic parameters are estimated by Bayesian inference from batch experimental data collected from literature. Probability distributions of the estimated parameters in addition to their point estimates are obtained by Markov Chain Monte Carlo simulation. The first‐principles model is observed in good agreement with the experimental data and can be further used for model predictions in robust control strategies. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2828–2838, 2014
Fluidized bed synthesis of carbon nanotubes: Reaction mechanism, rate controlling step and overall rate of reaction
Authors: Dasgupta Kinshuk , Joshi Jyeshtharaj B. , Singh Harvinderpal , Banerjee Srikumar
Published: April 2014

Carbon nanotubes have been synthesized from acetylene and methane in a fluidized bed by using ferrocene as the catalyst dispersed over carbon black support material. The agglomerate size of carbon black, loading of catalyst, total gas flow rate, partial pressure of reactant gas, temperature of synthesis, and time of synthesis have been varied to understand their effects on the yield of carbon nanotubes. A reaction mechanism consisting of eleven steps and the rate equations for these steps have been proposed. Formation of carbon molecules on the catalyst surface was found to be the rate controlling step in the temperature range of 700–807°C, with an activation energy 47 kJ mol−1, while diffusion through pores in the carbon black was found to be the rate controlling step in the temperature range of 807–1000°C with an activation energy of 7.6 kJ mol−1. A continuous deactivation of the catalyst, represented by an exponential decay, was observed. The products have been characterized by thermogravimetry, electron microscopy, and Raman spectroscopy. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2882–2892, 2014
Pathologic heterogeneity persists in early active multiple sclerosis lesions
Authors: Metz Imke , Weigand Stephen D. , Popescu Bogdan F. G. , Frischer Josa M. , Parisi Joseph E. , Guo Yong , Lassmann Hans , Brück Wolfgang , Lucchinetti Claudia F.
Published: April 2014

Objective

Multiple sclerosis (MS) lesions demonstrate immunopathological heterogeneity in patterns of demyelination. Previous cross‐sectional studies reported immunopatterns of demyelination were identical among multiple active demyelinating lesions from the same individual, but differed between individuals, leading to the hypothesis of intraindividual pathological homogeneity and interindividual heterogeneity. Other groups suggested a time‐dependent heterogeneity of lesions. The objective of our present study was to analyze tissue samples collected longitudinally to determine whether patterns of demyelination persist over time within a given patient.

Methods

Archival tissue samples derived from patients with pathologically confirmed central nervous system inflammatory demyelinating disease who had undergone either diagnostic serial biopsy or biopsy followed by autopsy were analyzed immunohistochemically. The inclusion criteria consisted of the presence of early active demyelinating lesions—required for immunopattern classification—obtained from the same patient at 2 or more time points.

Results

Among 1,321 surgical biopsies consistent with MS, 22 cases met the study inclusion criteria. Twenty‐one patients (95%) showed a persistence of immunopathological patterns in tissue sampled from different time points. This persistence was demonstrated for all major patterns of demyelination. A single patient showed features suggestive of both pattern II and pattern III on biopsy, but only pattern II among all active lesions examined at autopsy.

Interpretation

These findings continue to support the concept of patient‐dependent immunopathological heterogeneity in early MS and suggest that the mechanisms and targets of tissue injury may differ among patient subgroups. These observations have potentially significant implications for individualized therapeutic approaches. Ann Neurol 2014;75:728–738
UBQLN2 mutation causing heterogeneous X‐linked dominant neurodegeneration
Authors: Fahed Akl C. , McDonough Barbara , Gouvion Cynthia M. , Newell Kathy L. , Dure Leon S. , Bebin Martina , Bick Alexander G. , Seidman Jonathan G. , Harter Donald H. , Seidman Christine E.
Published: April 2014

We report a 5‐generation family with phenotypically diverse neurodegenerative disease including relentlessly progressive choreoathetoid movements, dysarthria, dysphagia, spastic paralysis, and behavioral dementia in descendants of a 67‐year‐old woman with amyotrophic lateral sclerosis. Disease onset varied with gender, occurring in male children and adult women. Exome sequence analyses revealed a novel mutation (c.1490C>T, p.P497L) in the ubiquilin‐2 gene (UBQLN2) with X‐linked inheritance in all studied affected individuals. As ubiquilin‐2–positive inclusions were identified in brain, we suggest that mutant peptide predisposes to protein misfolding and accumulation. Our findings expand the spectrum of neurodegenerative phenotypes caused by UBQLN2 mutations. ANN NEUROL 2014;75:793–798