bluuebunny/crossref_metadata_2025 huggingface dataset:
T-Scan Case Finishing Applications in Aesthetic Dentistry Assisted by the iTero Digital Impression System
Authors: Stevens, DDS Christopher J.
Published: January 2015

This chapter introduces the iTero digital impression system as a companion to the T-Scan Occlusal Analysis System. Occlusion as a component of aesthetic dentistry is discussed, and how the aesthetic case is aided by T-Scan force control at insertion. The chapter explains that brittle adhesive restorations cannot be evaluated occlusally prior to bonding. Combined with the spatial errors inherent with impression material setting and stone cast articulation, obtaining reliable interocclusal spatial relationships with adhesive restorations can be compromised. Alternatively, the iTero system accurately captures preparation shapes and the opposing interocclusal relationships, which eliminate typical, non-digital cast articulation errors. These clinical realities are illustrated in a10-unit porcelain veneer Case Report, where the iTero system and the T-Scan system are employed together. Finally, recommendations are made that Dental Medicine move towards digital impression making and accept the importance of the T-Scan system in occlusion to improve the standard of patient care.
An Assessment of Leadership Traits and the Success of Six Sigma Projects
Authors: Chamblee Jr. David Lee
Published: January 2015

In this chapter, more effective green belt leaders rated themselves higher than less effective green belt leaders on the following traits: articulate, perceptive, self-confident, self-assured, and determined. In addition, the more effective green belt leaders reported stronger upper management support than did less effective green belt leaders. In this chapter, more effective black belt leaders rated themselves higher than less effective black belt leaders on the following traits: articulate, perceptive, self-confident, self-assured, determined, dependable, and friendly. The more effective black belt leaders also reported stronger upper management support and project experience than did less effective black belt leaders. Clearly, in times of economic uncertainty and increasing global competiveness, managers need to be able to recognize the individuals who possess the needed traits to make their companies profitable.
Strategic Information System Planning in Healthcare Organizations
Authors: Lee Theresa , Ghapanchi Amir Hossein , Talaei-Khoei Amir , Ray Pradeep
Published: January 2015

The healthcare industry is a critical and growing part of economies worldwide. To provide better quality of care, and value for money, billions of dollars are being spent on bettering information systems in healthcare organizations. Strategic Information System Planning (SISP) is instrumental in making informed decisions to achieve the health organizations' goals and objectives. This paper undertakes a systematic review to gain insight into existing studies on SISP in healthcare organizations. Our systematic review of papers on SISP from 1985 to 2011 examines the background and trend of research into SISP in the healthcare industry, classification of topics in SISP, as well as sets of tools and guidelines to aid practitioners and the research community alike.
Exertional Sickling: Questions and Controversy
Authors: Blinder Morey A. , Russel Sarah
Published: January 2015

Sickle cell trait (SCT) occurs in about 8% of African-Americans and is often described to be of little clinical consequence. Over time, a number of risks have emerged, and among these are rare but catastrophic episodes of sudden death in athletes and other individuals associated with physical activities which is often described as exercise collapse associated with sickle trait (ECAST). Despite an epidemiologic link between SCT and sudden death as well as numerous case reports in both medical literature and lay press, no clear understanding of the key pathophysiologic events has been identified. Strategies for identification of individuals at risk and prevention of ECAST have been both elusive and controversial. Stakeholders have advocated for different approaches to this issue particularly with regard to screening for hemoglobin S. Furthermore, the recommendations and guidelines that are in place for the early recognition of ECAST and the prevention and treatment of the illness are not well defined and remain fragmented. Among the cases identified, those in collegiate football players in the United States are often highlighted. This manuscript examines these case studies and the current recommendations to identify areas of consensus and controversy regarding recommendations for prevention, recognition and treatment of ECAST.
Pseudomonas aeruginosa bacteraemia in two UK district hospitals
Authors: Enoch David A. , Kuzhively Julie , Sismey Andrew , Grynik Alina , Karas Johannis Andreas
Published: January 2015

Pseudomonas aeruginosa bacteraemia is associated with significant morbidity and mortality. We retrospectively studied the epidemiology of bacteraemia due to P. aeruginosa in two UK district hospitals so as to determine prevention strategies and assess the efficacy and compliance with local hospital antibiotic guidelines. Eighty six episodes occurred in 85 patients over the 3 year period. There was a year on year increase in bacteraemias, due predominantly to an increased proportion of community-onset episodes. Urinary catheterisation was a significant risk factor, along with anaemia, renal disease, malignancy and diabetes. The antibiotic guidelines were adequate for 92.8% of episodes but only 73.8% of patients received adequate therapy. Failure to follow the guidelines was principally due to unwillingness to use gentamicin due to concerns about nephrotoxicity. The antibiotic guidelines may need reviewing to accommodate this problem and further work is required to address urinary catheter care in both the hospital and community. Pseudomonas aeruginosa should be considered a significant pathogen when patients are admitted with features of sepsis.
Is it time to use checklists in mental health care auditing?
Authors: Abramowitz Moshe Z. , Polackiewicz Jacob , Grinshpoon Alexander
Published: January 2015

A key strategy for improving the quality of mental health care is the design and implementation of a mechanism for on-site inspection and clinical auditing. We discuss the use of checklists in auditing providing an objective, comprehensive system for recording and analyzing multi-disciplinary, clinical auditing in mental health services. We believe such an approach can identify potential risks and allow for better decision making.
Early Complete Remission of Osteoid Osteoma with Conservative Medical Management
Authors: Yokouchi Masahiro , Nagano Satoshi , Shimada Hirofumi , Nakamura Shunsuke , Setoguchi Takao , Kawamura Ichiro , Ishidou Yasuhiro , Komiya Setsuro
Published: January 2015

Osteoid osteoma is a benign bone tumor and causes persistent pain that is usually treated by surgery or ablation therapy. Conservative management with non-steroidal anti-inflammatory drugs (NSAIDs) is also used to avoid the morbidity associated with surgery or ablation therapy; however, it usually takes several years for the condition to resolve using conservative treatment. Our patient, a 10-year-old boy, presented with a 3-month history of a painful lesion in his leg. Plain radiography, bone scanning, computed tomography and magnetic resonance images showed the presence of a lesion with radiological features consistent with an osteoid osteoma of the cortex in the tibial diaphysis. The patient was treated with a usual dose of ibuprofen for 3 weeks. Within 3 weeks, his symptoms were almost completely resolved; he no longer needed NSAIDs and returned to normal life. Repeat imaging studies showed complete disappearance of the nidus within 2.5 years after the resolution of symptoms.
Approaches to Management of Beta-Thalassemia Intermedia
Authors: Maakaron Joseph E. , Taher Ali T.
Published: January 2015

Thalassemia intermedia is a genetically diverse group of diseases that is the result of an imbalance in the production of the alpha and beta chains with ensuing chronic hemolysis, ineffective erythropoiesis, and iron overload.Resulting complications include bone changes, hypercoagulability, and end-organ damage due to iron overload. This decade has witnessed major breakthroughs in the management of thalassemia. In this article, we examine these novelties in therapy including iron chelation therapy, stem cell transplant, and gene therapy.Iron chelation therapy has been revolutionized with the advent of deferasirox, a once-daily oral iron chelator, that has been shown to be safe and efficacious.Gene therapy was also at the core of this revolution with the discovery of novel gene elements and viral vectors allowing for better control and improved outcomes.
Thalassemia: A Dreadful Disease Turned to a Chronic Condition
Authors: Loukopoulos Dimitris
Published: January 2015

Thalassemia is a disease with many challenging aspects [...]
Blood Transfusion: Safety, Optimisation and New Advances
Authors: Allard Shubha
Published: January 2015

This article is distributed under the terms of the Creative Commons Attribution [...]
Thalassemia in Israel: 2012
Authors: Stark Pinhas
Published: January 2015

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License (by-nc 3.0) which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited [...]
The Molecular and Cellular Basis of Iron Toxicity in Iron Overload (IO) Disorders. Diagnostic and Therapeutic Approaches
Authors: Cabantchik Zvi Ioav , Sohn Yan Sung , Breuer William , Espósito Breno Pannia
Published: January 2015

Abnormal iron accumulation in human tissues and oxidative damage are emerging issues in the medical field (1,2) [...]
Genetic/Metabolic Effect of Iron Metabolism and Rare Anemias
Authors: Camaschella Clara
Published: January 2015

Advances in iron metabolism have allowed a novel classification of iron disorders and to identify previously unknown diseases. These disorders include genetic iron overload (hemochromatosis) and inherited iron-related anemias, in some cases accompanied by iron overload. Rare inherited anemias may affect the hepcidin pathway, iron absorption, transport, utilization and recycling. Among the genetic iron-related anemias the most common form is likely the iron-refractory iron-deficiency anemia (IRIDA), due to mutations of the hepcidin inhibitor TMPRSS6 encoding the serine protease matriptase-2. IRIDA is characterized by hepcidin up-regulation, decrease iron absorption and macrophage recycling and by microcytic- hypochromic anemia, unresponsive to oral iron. High serum hepcidin levels may suggest the diagnosis, which requires demonstrating the causal TMPRSS6 mutations by gene sequencing. Other rare microcytic hypochromic anemias associated with defects of iron transport-uptake are the rare hypotransferrinemia, and DMT1 and STEAP3 mutations. The degree of anemia is variable and accompanied by secondary iron overload even in the absence of blood transfusions. This is due to the iron-deficient or expanded erythropoiesis that inhibits hepcidin transcription, increases iron absorption, through the erythroid regulator, as in untransfused beta-thalassemia. Sideroblastic anemias are due to decreased mitochondrial iron utilization for heme or sulfur cluster synthesis. Their diagnosis requires demonstrating ringed sideroblasts by Perl’s staining of the bone marrow smears. The commonest X-linked form is due to deltaamino- levulinic-synthase-2-acid (ALAS2) mutations. The recessive, more severe form, affects SLC25A38, which encodes a potential mitochondrial importer of glycine, an amino acid essential for ALA synthesis and thus results in heme deficiency. Two disorders affect iron/sulfur cluster biogenesis: deficiency of the ATP-binding cassette B7 (ABCB7) causes X-linked sideroblastic anemia/ataxia, likely impairing the activity of ferrochelatase, which is an iron/sulfur-cluster- dependent enzyme. A recessive form affects GLRX5, a protein involved in the iron/sulfur cluster biogenesis. Aceruloplasminemia is a rare recessive syndrome characterized by anemia, diabetes, retinal degeneration, ataxia and other neurological symptoms, low serum iron but high serum ferritin, due to decreased iron recycling from macrophages and other cells. The study of these rare conditions has greatly contributed to our understanding of iron transport, utilization and recycling. Their distinction is clinically essential in order to plan the best treatment.
Thalassaemia Major and the Heart
Authors: Walker J. Malcolm
Published: January 2015

Disorders of haemoglobin synthesis are the commonest monogenetic disorders worldwide [...]
Epidemiology of Non-Transfusion Dependent Thalassaemias: An Emerging Global Concern
Authors: Eleftheriou Androulla
Published: January 2015

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License [...]
Unsaturated water flux at mid and lower slope positions within an inclined landscape of the Dark Brown soil zone in southern Alberta
Authors: Miller J. J. , Chanasyk D. S.
Published: January 2015

Miller, J. J. and Chanasyk, A. S. 2015. Unsaturated water flux at mid and lower slope positions within an inclined landscape of the Dark Brown soil zone in southern Alberta. Can. J. Soil Sci. 95: 27–36. Little research has quantified vertical-unsaturated water flux below the root zone for mid and lower slope positions within inclined, low-relief, and longer-slope landscapes of the Dark Brown soil zone of the Canadian prairies. We measured soil moisture (0.23–1.22 m) in the field at mid and lower slope positions in southern Alberta from May to October in 1985 and 1986. Undisturbed soil cores were taken from soil horizons and saturated hydraulic conductivity and soil moisture retention were determined in the laboratory. Vertical-unsaturated water flux below the root zone was calculated between 1.07 and 1.22 m depths below ground surface using the hydraulic gradient method. Water fluxes for the 2 yr ranged from <10−11to 10−10m s−1at the mid slope position, and from <10−11m s−1to 10−9m s−1at the lower slope position, and were consistent with some other studies. Cumulative water flux was dominantly downward (−2.2 to −3.4 mm) at the mid slope position and this flow direction was consistent with this Orthic Dark Brown Chernozemic soil that was located in a “recharge area”. Cumulative water flux was dominantly upward at the lower slope position in 1985 (1.4 mm) and dominantly downward but of very low magnitude in 1986 (−0.1 mm), and this flow direction was consistent with this saline Gleyed Regosol and “saline seep”. Cumulative water fluxes as a percentage of annual precipitation were 0.8 to 1.8% at the mid slope position and 0.3 to 0.5% at the lower slope position.
Probabilistic hurricane-induced storm surge hazard assessment in Guadeloupe, Lesser Antilles
Authors: Krien Y. , Dudon B. , Roger J. , Zahibo N.
Published: January 2015

Abstract. Current storm surge hazard maps in the French West Indies are essentially based on simple statistical methods using limited historical data and early low-resolution models which do not take the effect of waves into account. In this paper, we infer new 100 and 1000 year surge levels in Guadeloupe from the numerical modelling of storm surges induced by a large set of synthetic events that are in statistical agreement with features of historical hurricanes in the North Atlantic Basin between 1980 and 2011. Computations are performed using the wave-current coupled model ADCIRC-SWAN with high grid resolutions (up to 40–60 m) in the coastal and wave dissipation areas. This model is validated against observations during past events such as hurricane HUGO (1989). Results are generally found to be in reasonable agreement with past studies in areas where surge is essentially wind-driven, but to differ significantly in coastal regions where the transfer of momentum from waves to the water column constitutes a non-negligible part of the total surge. The methodology, which can be applied to other islands in the Lesser Antilles, allows to obtain storm surge level maps that can be of major interest for coastal planners and decision makers in terms of risk management.
Magma storage and plumbing of adakite-type post-ophiolite intrusions in the Sabzevar ophiolitic zone, northeast Iran
Authors: Jamshidi K. , Ghasemi H. , Troll V. R. , Sadeghian M. , Dahren B.
Published: January 2015

Abstract. Subduction-related adakite-type intrusive rocks emplaced into the late Cretaceous–Paleocene Sabzevar ophiolite zone, northeast Iran, range from Mg-andesite to rhyodacite in composition. Here we investigate the magma supply system to these subvolcanic intrusive rocks by applying thermobarometric mineral and mineral–melt equilibrium models, including amphibole thermobarometry, plagioclase–melt thermobarometry and clinopyroxene–melt barometry. Based on the results of these thermobarometric models, plagioclase crystallized dominantly at pressures of ~350 (130 to 468) MPa, while amphiboles record both low pressures (~300 MPa) and very high pressures (>700 MPa) of crystallization. The latter is supported by the calculated pressures for clinopyroxene crystallization (550 to 730 MPa). The association of amphibole with clinopyroxene and no plagioclase in the most primitive samples (Mg-andesites) is consistent with amphibole fractionation from very hydrous magmas at deep crustal levels of the plumbing system, which may have been a key process in intensifying adakite-type affinities in this rock suite. Barometry, combined with frequent disequilibrium features such as oscillatory-zoned and sieve-textured plagioclase crystals with An-rich overgrowths in more evolved samples, implies that final magma differentiation occurred in an open upper crustal magma system that developed progressively stronger compositional modifications during high-level magma storage.
Fear of Falling Is Associated with Recurrent Falls in People with Multiple Sclerosis
Authors: Mazumder Rajarshi , Lambert William E. , Nguyen Thuan , Bourdette Dennis N. , Cameron Michelle H.
Published: January 2015

Background: People with multiple sclerosis (MS) fall frequently, and there are few clinically valid tools to measure the risk factors for falls. We assessed the unidimensionality of the 7-item Falls Efficacy Scale–International (FES-I), a measure of fear of falling, and determined whether the 7-item FES-I is associated with recurrent falls in people with MS.

Methods: Falls were counted prospectively for 6 months using fall calendars in 58 people with MS (age, 18–50 years; Expanded Disability Status Scale score, 0–6). The FES-I was administered at baseline, and its unidimensionality was assessed by confirmatory factor analysis. The relationship between FES-I score and future falls, after adjusting for recurrent falls in the past year, was assessed by logistic regression.

Results: Fifty-four participants who completed all assessments were included in the analysis. Goodness-of-fit indices confirmed a single-factor solution for the 7-item FES-I (discrepancy χ2, P = .101; Tucker-Lewis index, 0.953; comparative fit index, 0.969; root mean square error of approximation, 0.098). There was a significant association between fear of falling and falls in the following 3 months, independent of recurrent falls in the past year (odds ratio = 1.22, 95% confidence interval, 1.04–1.43, P = .016).

Conclusions: The 7-item FES-I demonstrates good construct validity, allowing the total score to be used as a measure of fear of falling in people with MS. Fear of falling, as measured by the 7-item FES-I, is associated with future recurrent falls independent of past recurrent falls in people with MS.
Clinical Significance of Gastrointestinal and Flushing Events in Patients with Multiple Sclerosis Treated with Delayed-Release Dimethyl Fumarate
Authors: Phillips J. Theodore , Selmaj Krzysztof , Gold Ralf , Fox Robert J. , Havrdova Eva , Giovannoni Gavin , Abourjaily Heather , Pace Amy , Novas Mark , Hotermans Christophe , Viglietta Vissia , Meltzer Leslie
Published: January 2015

Background: In the phase 3 DEFINE and CONFIRM trials, flushing and gastrointestinal (GI) events were associated with delayed-release dimethyl fumarate (DMF; also known as gastroresistant DMF) treatment in people with relapsing-remitting multiple sclerosis (MS). To investigate these events, a post hoc analysis of integrated data from these trials was conducted, focusing on the initial treatment period (months 0−3) with the recommended DMF dosage (240 mg twice daily).

Methods: Eligibility criteria included age 18 to 55 years, relapsing-remitting MS diagnosis, and Expanded Disability Status Scale score 0 to 5.0. Patients were randomized and received treatment with placebo (n = 771) or DMF (n = 769) for up to 2 years. Adverse events were recorded at scheduled clinic visits every 4 weeks.

Results: The incidence of GI and flushing events was highest in the first month of treatment. In months 0 to 3, the incidence of GI events was 17% in the placebo group and 27% in the DMF group and the incidence of flushing and related symptoms was 5% in the placebo group and 37% in the DMF group. Most GI and flushing events were of mild or moderate severity and resolved during the study. The events were temporally associated with the use of diverse symptomatic therapies (efficacy not assessed) and infrequently led to DMF discontinuation.

Conclusions: This integrated analysis indicates that in a clinical trial setting, GI and flushing events associated with DMF treatment are generally transient and mild or moderate in severity and uncommonly lead to treatment discontinuation.
Heart Rate Variability: New Perspectives on Physiological Mechanisms, Assessment of Self-regulatory Capacity, and Health Risk
Authors: Mccraty Rollin , Shaffer Fred
Published: January 2015

Heart rate variability, the change in the time intervals between adjacent heartbeats, is an emergent property of interdependent regulatory systems that operates on different time scales to adapt to environmental and psychological challenges. This article briefly reviews neural regulation of the heart and offers some new perspectives on mechanisms underlying the very low frequency rhythm of heart rate variability. Interpretation of heart rate variability rhythms in the context of health risk and physiological and psychological self-regulatory capacity assessment is discussed. The cardiovascular regulatory centers in the spinal cord and medulla integrate inputs from higher brain centers with afferent cardiovascular system inputs to adjust heart rate and blood pressure via sympathetic and parasympathetic efferent pathways. We also discuss the intrinsic cardiac nervous system and the heart-brain connection pathways, through which afferent information can influence activity in the subcortical, frontocortical, and motor cortex areas. In addition, the use of realtime HRV feedback to increase self-regulatory capacity is reviewed. We conclude that the heart's rhythms are characterized by both complexity and stability over longer time scales that reflect both physiological and psychological functional status of these internal self-regulatory systems.
An evaluation of age estimation using teeth from South Asian River dolphins (Platanistidae)
Authors: Lockyer Christina H , Braulik Gill T
Published: January 2015

The South Asian river dolphins (Platanista gangetica minor and P. g. gangetica) are endangered, geographically isolated, freshwater cetaceans. Accurate age estimation of individuals is an important aspect of population biology as it is used for calculating parameters such as age at maturity and reproduction, longevity, and growth and survival rates. However this has never been comprehensively studied for this endangered cetacean family. A sample of 41 teeth from 29 skulls stored in museum collections was available. We compared two different aging methods to select the most appropriate. This involved decalcification and freeze-sectioning of teeth at variable thicknesses (10–25 micron), and staining with 1) Toluidine Blue, or 2) Ehrlichs Acid Haematoxylin. Stains were then compared for readability of Growth Layer Groups (GLG). The optimum section was found at 20 micron using Erhlichs Acid Haematoxylin. Both dentinal and cemental GLG were readable and comparable, but cemental GLG were generally easier to interpret because they were better defined. Ages varied from newborn / young of year (with none or only a neonatal line present) to a maximum age of 30 GLG. There is currently no validation available for GLG deposition rate, but it is likely annual because of the extreme seasonal changes in the river habitat.
Questionnaire evaluating teaching competencies in the university environment. Evaluation of teaching competencies in the university
Authors: Moreno-Murcia Juan Antonio , Silveira Torregrosa Yolanda , Belando Pedreño Noelia
Published: January 2015

The objective of this study was to design and validate a measuring instrument to evaluate the performance of university professors. The Evaluation of Teaching Performance (CEID [Centro de Estudios e Investigaciones Docentes (Center for Teaching Studies and Research)]) questionnaire was administered to 1297 university students. Various factor analyses were performed (exploratory and confirmatory), of the internal consistency, descriptive statistics, and correlation of all of the items. The data obtained confirmed a suitable psychometric structure for the CEID scale, which was made up of three dimensions (planning, development, and result). It is therefore concluded that it is a valid and reliable instrument for evaluating the performance of a university professor.
The influence of photosynthetic acclimation to rising CO2 and warmer temperatures on leaf and canopy photosynthesis models
Authors: Bagley Justin , Rosenthal David M. , Ruiz‐Vera Ursula M. , Siebers Matthew H. , Kumar Praveen , Ort Donald R. , Bernacchi Carl J.
Published: January 2015

There is an increasing necessity to understand how climate change factors, particularly increasing atmospheric concentrations of CO2 ([CO2]) and rising temperature, will influence photosynthetic carbon assimilation (A). Based on theory, an increased [CO2] concomitant with a rise in temperature will increase A in C3 plants beyond that of an increase in [CO2] alone. However, uncertainty surrounding the acclimation response of key photosynthetic parameters to these changes can influence this response. In this work, the acclimation responses of C3 photosynthesis for soybean measured at the SoyFACE Temperature by Free‐Air CO2 Enrichment experiment are incorporated in a leaf biochemical and canopy photosynthesis model. The two key parameters used as model inputs, the maximum velocity for carboxylation (Vc,max) and maximum rate of electron transport (Jmax), were measured in a full factorial [CO2] by temperature experiment over two growing seasons and applied in leaf‐ and canopy‐scale models to (1) reassess the theory of combined increases in [CO2] and temperature on A, (2) determine the role of photosynthetic acclimation to increased growth [CO2] and/or temperature in leaf and canopy predictions of A for these treatments, and (3) assess the diurnal and seasonal differences in leaf‐ and canopy‐scale A associated with the imposed treatments. The results demonstrate that the theory behind combined increases in [CO2] and temperature is sound; however, incorporating more recent parameterizations into the photosynthesis model predicts greater increases in A when [CO2] and temperature are increased together. Photosynthetic acclimation is shown to decrease leaf‐level A for all treatments; however, in elevated [CO2] the impact of acclimation does not result in any appreciable loss in photosynthetic potential at the canopy scale. In this analysis, neglecting photosynthetic acclimation in heated treatments, with or without concomitant rise in [CO2], leads to modeled overestimates of carbon gain for soybean under future predicted conditions.
A compositional origin to ultralow‐velocity zones
Authors: Brown Samuel P. , Thorne Michael S. , Miyagi Lowell , Rost Sebastian
Published: January 2015

We analyzed vertical component short‐period ScP waveforms for 26 earthquakes occurring in the Tonga‐Fiji trench recorded at the Alice Springs Array in central Australia. These waveforms show strong precursory and postcursory seismic arrivals consistent with ultralow‐velocity zone (ULVZ) layering beneath the Coral Sea. We used the Viterbi sparse spike detection method to measure differential travel times and amplitudes of the postcursor arrival ScSP and the precursor arrival SPcP relative to ScP. We compare our measurements to a database of 340,000 synthetic seismograms finding that these data are best fit by a ULVZ model with an S wave velocity reduction of 24%, a P wave velocity reduction of 23%, a thickness of 8.5 km, and a density increase of 6%. This 1:1 VS:VP velocity decrease is commensurate with a ULVZ compositional origin and is most consistent with highly iron enriched ferropericlase.
Ice collapse over trapped water bodies on Enceladus and Europa
Authors: Walker C. C. , Schmidt B. E.
Published: January 2015

Icy satellite surfaces are riddled with geological indicators that can inform what lies beneath. Here we investigate effects of trapped or perched subsurface liquid water on the surface above. We use two models to investigate these effects: first, an analytical model to determine the flexural response of an ice shell to the existence of trapped water, and second, a discrete element model that simulates collapse of ice through granular interactions to determine possible topography that would result from this stress being placed on the ice. We find that for Europa's likely trapped water pockets below chaos terrains and a localized sea below Enceladus' South Polar Terrain, these models can reproduce observed geology of both features. Thus, we postulate that it is likely that Europa's chaos terrains and Enceladus' South Polar Terrain formed due to a similar mechanism: ice collapse above trapped water.
Cyclonic entrainment of preconditioned shelf waters into a frontal eddy
Authors: Everett J. D. , Macdonald H. , Baird M. E. , Humphries J. , Roughan M. , Suthers I. M.
Published: January 2015

The volume transport of nutrient‐rich continental shelf water into a cyclonic frontal eddy (entrainment) was examined from satellite observations, a Slocum glider and numerical simulation outputs. Within the frontal eddy, parcels of water with temperature/salinity signatures of the continental shelf (18–19°C and >35.5, respectively) were recorded. The distribution of patches of shelf water observed within the eddy was consistent with the spiral pattern shown within the numerical simulations. A numerical dye tracer experiment showed that the surface waters (≤50 m depth) of the frontal eddy are almost entirely (≥95%) shelf waters. Particle tracking experiments showed that water was drawn into the eddy from over 4° of latitude (30–34.5°S). Consistent with the glider observations, the modeled particles entrained into the eddy sunk relative to their initial position. Particles released south of 33°S, where the waters are cooler and denser, sunk 34 m deeper than their release position. Distance to the shelf was a critical factor in determining the volume of shelf water entrained into the eddy. Entrainment reduced to 0.23 Sv when the eddy was furthest from the shelf, compared to 0.61 Sv when the eddy was within 10 km of the shelf. From a biological perspective, quantifying the entrainment of shelf water into frontal eddies is important, as it is thought to play a significant role in providing an offshore nursery habitat for coastally spawned larval fish.
Biosphere‐climate interactions in a changing climate over North America
Authors: Garnaud Camille , Sushama Laxmi
Published: January 2015

This study focuses on projected changes to vegetation characteristics and their interactions with the atmosphere under future climatic conditions over North America, using four transient climate change simulations of the Canadian Regional Climate Model (CRCM5). Here CRCM5 performs dynamical downscaling of the Canadian Earth System Model (CanESM2) simulated data, for Representative Concentration Pathways (RCPs) 4.5 and 8.5. For each RCP, two CRCM5 simulations are performed—one with static vegetation phenology and the other with dynamic vegetation phenology—for the 1950–2100 period over North America. The dynamic vegetation model used here is the Canadian Terrestrial Ecosystem Model. Results show that the extension of the growing season under future climatic conditions in the dynamic phenology simulations leads to higher annual vegetation productivity and biomass. In comparison with projected changes based on CRCM5 with static phenology, CRCM5 with phenology dynamics leads to an albedo‐mediated warming enhancement across most of North America in spring. In summer, results suggest a warming enhancement in the northern latitudes and an attenuation of warming for more southern regions due to hydrological feedbacks. Furthermore, results suggest that vegetation enhances its water‐use efficiency with rising atmospheric CO2 concentrations. Over southeastern United States, in the dynamic phenology simulation corresponding to the RCP8.5 scenario, the adverse effects of the projected increase in temperatures and decrease in precipitation on vegetation dominate the CO2 fertilization effect, leading to decreasing trends in productivity during the 2071–2100 period. This study thus clearly demonstrates that phenology dynamics modulate greenhouse gas‐mediated warming through various biophysical feedbacks.
Pore‐scale and multiscale numerical simulation of flow and transport in a laboratory‐scale column
Authors: Scheibe Timothy D. , Perkins William A. , Richmond Marshall C. , McKinley Matthew I. , Romero‐Gomez Pedro D. J. , Oostrom Mart , Wietsma Thomas W. , Serkowski John A. , Zachara John M.
Published: January 2015

Pore‐scale models are useful for studying relationships between fundamental processes and phenomena at larger (i.e., Darcy) scales. However, the size of domains that can be simulated with explicit pore‐scale resolution is limited by computational and observational constraints. Direct numerical simulation of pore‐scale flow and transport is typically performed on millimeter‐scale volumes at which X‐ray computed tomography (XCT), often used to characterize pore geometry, can achieve micrometer resolution. In contrast, laboratory experiments that measure continuum properties are typically performed on decimeter‐scale columns. At this scale, XCT resolution is coarse (tens to hundreds of micrometers) and prohibits characterization of small pores and grains. We performed simulations of pore‐scale processes over a decimeter‐scale volume of natural porous media with a wide range of grain sizes, and compared to results of column experiments using the same sample. Simulations were conducted using high‐performance codes executed on a supercomputer. Two approaches to XCT image segmentation were evaluated, a binary (pores and solids) segmentation and a ternary segmentation that resolved a third category (porous solids with pores smaller than the imaged resolution). We used a multiscale Stokes‐Darcy simulation method to simulate the combination of Stokes flow in large open pores and Darcy‐like flow in porous solid regions. Flow and transport simulations based on the binary segmentation were inconsistent with experimental observations because of overestimation of large connected pores. Simulations based on the ternary segmentation provided results that were consistent with experimental observations, demonstrating our ability to successfully model pore‐scale flow over a column‐scale domain.
A Bayesian kriging approach for blending satellite and ground precipitation observations
Authors: Verdin Andrew , Rajagopalan Balaji , Kleiber William , Funk Chris
Published: January 2015

Drought and flood management practices require accurate estimates of precipitation. Gauge observations, however, are often sparse in regions with complicated terrain, clustered in valleys, and of poor quality. Consequently, the spatial extent of wet events is poorly represented. Satellite‐derived precipitation data are an attractive alternative, though they tend to underestimate the magnitude of wet events due to their dependency on retrieval algorithms and the indirect relationship between satellite infrared observations and precipitation intensities. Here we offer a Bayesian kriging approach for blending precipitation gauge data and the Climate Hazards Group Infrared Precipitation satellite‐derived precipitation estimates for Central America, Colombia, and Venezuela. First, the gauge observations are modeled as a linear function of satellite‐derived estimates and any number of other variables—for this research we include elevation. Prior distributions are defined for all model parameters and the posterior distributions are obtained simultaneously via Markov chain Monte Carlo sampling. The posterior distributions of these parameters are required for spatial estimation, and thus are obtained prior to implementing the spatial kriging model. This functional framework is applied to model parameters obtained by sampling from the posterior distributions, and the residuals of the linear model are subject to a spatial kriging model. Consequently, the posterior distributions and uncertainties of the blended precipitation estimates are obtained. We demonstrate this method by applying it to pentadal and monthly total precipitation fields during 2009. The model's performance and its inherent ability to capture wet events are investigated. We show that this blending method significantly improves upon the satellite‐derived estimates and is also competitive in its ability to represent wet events. This procedure also provides a means to estimate a full conditional distribution of the “true” observed precipitation value at each grid cell.
Challenges in modeling unstable two‐phase flow experiments in porous micromodels
Authors: Ferrari Andrea , Jimenez‐Martinez Joaquin , Borgne Tanguy Le , Méheust Yves , Lunati Ivan
Published: January 2015

The simulation of unstable invasion patterns in porous media flow is very challenging because small perturbations are amplified, so that slight differences in geometry or initial conditions result in significantly different invasion structures at later times. We present a detailed comparison of pore‐scale simulations and experiments for unstable primary drainage in porous micromodels. The porous media consist of Hele‐Shaw cells containing cylindrical obstacles. By means of soft lithography, we have constructed two experimental flow cells, with different degrees of heterogeneity in the grain size distribution. As the defending (wetting) fluid is the most viscous, the interface is destabilized by viscous forces, which promote the formation of preferential flow paths in the form of a branched finger structure. We model the experiments by solving the Navier‐Stokes equations for mass and momentum conservation in the discretized pore space and employ the Volume of Fluid (VOF) method to track the evolution of the interface. We test different numerical models (a 2‐D vertical integrated model and a full‐3‐D model) and different initial conditions, studying their impact on the simulated spatial distributions of the fluid phases. To assess the ability of the numerical model to reproduce unstable displacement, we compare several statistical and deterministic indicators. We demonstrate the impact of three main sources of error: (i) the uncertainty on the pore space geometry, (ii) the fact that the initial phase configuration cannot be known with an arbitrarily small accuracy, and (iii) three‐dimensional effects. Although the unstable nature of the flow regime leads to different invasion structures due to small discrepancies between the experimental setup and the numerical model, a pore‐by‐pore comparison shows an overall satisfactory match between simulations and experiments. Moreover, all statistical indicators used to characterize the invasion structures are in excellent agreement. This validates the modeling approach, which can be used to complement experimental observations with information about quantities that are difficult or impossible to measure, such as the pressure and velocity fields in the two fluid phases.
Direct Bandgap Transition in Many‐Layer MoS2 by Plasma‐Induced Layer Decoupling
Authors: Dhall Rohan , Neupane Mahesh R. , Wickramaratne Darshana , Mecklenburg Matthew , Li Zhen , Moore Cameron , Lake Roger K. , Cronin Stephen
Published: January 2015

We report a robust method for engineering the optoelectronic properties of many‐layer MoS2 using low‐energy oxygen plasma treatment. Gas phase treatment of MoS2 with oxygen radicals generated in an upstream N2–O2 plasma is shown to enhance the photoluminescence (PL) of many‐layer, mechanically exfoliated MoS2 flakes by up to 20 times, without reducing the layer thickness of the material. A blueshift in the PL spectra and narrowing of linewidth are consistent with a transition of MoS2 from indirect to direct bandgap material. Atomic force microscopy and Raman spectra reveal that the flake thickness actually increases as a result of the plasma treatment, indicating an increase in the interlayer separation in MoS2. Ab initio calculations reveal that the increased interlayer separation is sufficient to decouple the electronic states in individual layers, leading to a transition from an indirect to direct gap semiconductor. With optimized plasma treatment parameters, we observed enhanced PL signals for 32 out of 35 many‐layer MoS2 flakes (2–15 layers) tested, indicating that this method is robust and scalable. Monolayer MoS2, while direct bandgap, has a small optical density, which limits its potential use in practical devices. The results presented here provide a material with the direct bandgap of monolayer MoS2, without reducing sample thickness, and hence optical density.
Tetracyclopenta[def,jkl,pqr,vwx]tetraphenylene: A Potential Tetraradicaloid Hydrocarbon
Authors: Nobusue Shunpei , Miyoshi Hirokazu , Shimizu Akihiro , Hisaki Ichiro , Fukuda Kotaro , Nakano Masayoshi , Tobe Yoshito
Published: January 2015

A tetramesityl derivative of hitherto unknown tetracyclopenta[def,jkl,pqr,vwx]tetraphenylene (TCPTP), which is a potential tetraradicaloid hydrocarbon, was synthesized. Theoretical calculations based on spin‐flip time‐dependent density functional theory predict that the closed‐shell D2h form of TCPTP is more stable than the open‐shell D4h form with its slightly tetraradical character. The tetramesityl derivative (Mes)4‐TCPTP exhibits remarkable antiaromaticity as a result of the peripheral 20‐π‐electron circuit, which causes an absorption maximum at a long wavelength and a small HOMO–LUMO gap. In solution, (Mes)4‐TCPTP most likely adopts rapidly equilibrating D2h structures that interconvert via the D4h transition state. X‐ray crystallographic analysis showed (Mes)4‐TCPTP as an approximate D2h structure.
Cost-effectiveness of ultrasound-guided foam sclerotherapy, endovenous laser ablation or surgery as treatment for primary varicose veins from the randomized CLASS trial
Authors: Tassie E , Scotland G , Brittenden J , Cotton S C , Elders A , Campbell M K , Campbell B , Gough M , Burr J M , Ramsay C R
Published: January 2015

Background

The treatment of patients with varicose veins constitutes a considerable workload and financial burden to the National Health Service. This study aimed to assess the cost-effectiveness of ultrasound-guided foam sclerotherapy (UGFS) and endovenous laser ablation (EVLA) compared with conventional surgery as treatment for primary varicose veins.

Methods

Participant cost and utility data were collected alongside the UK CLASS multicentre randomized clinical trial, which compared EVLA, surgery and UGFS. Regression methods were used to estimate the effects of the alternative treatments on costs to the health service and quality-adjusted life-years (QALYs) at 6 months. A Markov model, incorporating available evidence on clinical recurrence rates, was developed to extrapolate the trial data over a 5-year time horizon.

Results

Compared with surgery at 6 months, UGFS and EVLA reduced mean costs to the health service by £655 and £160 respectively. When additional overhead costs associated with theatre use were included, these cost savings increased to £902 and £392 respectively. UGFS produced 0·005 fewer QALYs, whereas EVLA produced 0·011 additional QALYs. Extrapolating to 5 years, EVLA was associated with increased costs and QALYs compared with UGFS (costing £3640 per QALY gained), and generated a cost saving (£206–439) and QALY gain (0·078) compared with surgery. Applying a ceiling willingness-to-pay ratio of £20 000 per QALY gained, EVLA had the highest probability (78·7 per cent) of being cost-effective.

Conclusion

The results suggest, for patients considered eligible for all three treatment options, that EVLA has the highest probability of being cost-effective at accepted thresholds of willingness to pay per QALY.
In Situ Analysis for Herbal Pieces of Aconitum Plants by Using Direct Analysis in Real Time Mass Spectrometry
Authors: Zhou Feng , Zhu Hongbin , Liu Shu , Ma Kang , Song Fengrui , Liu Zhiqiang
Published: January 2015

In this study, an extend application was developed to in situ analyze the herbal pieces of Aconitum plants by Direct Analysis in Real Time Mass Spectrometry (DART‐MS). Nearly all aconitine‐type alkaloids can be desorbed and ionized in this method, including diester diterpenoid aconitines (DDAs), monoester diterpenoid aconitines (MDAs) and some other diterpenoid aconitines. The spectra of in situ analysis for the herbal pieces of aconitum plants are similar with that of their extracts. Radix Aconiti and Radix Aconiti Kusnezoffii can be distinguished from each other by the intensity differences of character fragment ions from MDAs, such as m/z 586, 572, and 556. The qualified and unqualified herbal pieces can be also identified by the relative abundances of DDAs. The RSD of the relative abundances of some character ions at m/z 556, 586, and 590 were 13.53%, 4.03%, and 12.03%, respectively. So this in situ analytical method can identify both the types of Aconitum preparata and their quality. It provides the following advantages in the analysis of Chinese herbs: fast detection without much pretreatment, high‐throughput analysis, and reduction of pollution without any organic solvent.
Synthesis and Luminescence of Eu‐N2,N6‐Bis(2‐hydroxyethyl)pyridine‐2,6‐dicarboxamide Complexes Containing Mesoporous Material
Authors: Li Zheng , Zuo Siyu , Zhou Jingjian , Yuan Xiao , Song Yishan , Zhang Hua
Published: January 2015

Ligand N2,N6‐bis(2‐hydroxyethyl)pyridine‐2,6‐dicarboxamide (L=BHPC) was synthesized and used to construct lanthanide‐based mesoporous material Eu‐L‐MCM‐41. In the structure of resulting Eu‐L‐MCM‐41, Eu3+ was chelated by BHPC, and the Eu‐L complexes were anchored into the forming MCM‐41 host by the reaction between the hydroxyl group and active Si‐OH. The mesoporous material Eu‐L‐MCM‐41 was characterized by UV, IR, small‐angle X‐ray diffraction (SAXRD) patterns, nitrogen adsorption/desorption isotherms, TGA and fluorescence spectra. The results indicate that ligand and Eu3+ have been introduced into the MCM‐41 host, and Eu‐L‐MCM‐41 exhibits characteristic luminescence of Eu3+.