bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective Reporting of Factual Content by Commercial Media
Authors: Zhu Yi , Dukes Anthony
Published: June 2014

The authors study the market for factual content and examine whether competition increases or decreases its provision. Factual content is supplied by commercial media firms, which observe a set of facts depicting the state of the world and selectively decide how to report them. Consumers value content that matches their opinion, which incentivizes media firms to slant their reports by omitting certain facts. Novel features in the authors’ model include consumers’ ability to anticipate the media's incentives for slant and the requirement that all media stances must be supported by facts. Furthermore, consumers find reports with more facts to be more convincing. Despite consumers’ ability to detect slant and their demand for factual support, the research shows that competition results in consumers reading fewer facts and being unable to update their prior beliefs about the state of the world. The authors also find that a monopoly medium may be more polarizing than competitive media and that polarized reporting can be less biased.
Measuring Freeze and Thaw Damage in Mortars Containing Deicing Salt Using a Low-Temperature Longitudinal Guarded Comparative Calorimeter and Acoustic Emission
Authors: Farnam Yaghoob , Bentz Dale , Sakulich Aaron , Flynn Daniel , Weiss Jason
Published: June 2014

Deicing salts are often applied to the surface of pavements and bridge decks in the winter to melt ice, thereby improving safety for the traveling public. In this paper, the influence of NaCl deicing salt on freezing and thawing temperatures of pore solution and corresponding damage of mortar specimens were investigated. A low-temperature longitudinal guarded comparative calorimeter (LGCC) was developed to cool down a mortar sample at a rate of 2°C/h and to re-heat the mortar at a rate of 4°C/h. Heat flux during freezing and thawing cycles was monitored, and the temperatures at which freezing and thawing events occurred were detected. During cooling and heating, acoustic emission (AE) activity was measured to quantify the damage (cracking) caused by aggregate/paste thermal mismatch and/or phase changes. The results show that NaCl solution in a mortar sample freezes at a lower temperature than the value expected from its bulk phase diagram because of under-cooling. Conversely, the frozen solution in mortar melts at the same melting temperature as the bulk frozen NaCl solution. As the salt concentration increases, the freezing temperature is lowered. For samples containing more highly concentrated solutions, an additional exothermic event is observed whose corresponding temperature is greater than the aqueous NaCl liquidus line in the phase diagram. Damage also begins to occur at this temperature. For mortar samples saturated by solutions with 5 % and 15 % NaCl by mass, greater freeze/thaw damage is observed. The AE calorimeter developed herein is applicable for investigating damage behavior during freezing and thawing of different phases in pore solution (in mortars).
The Role of Concrete Industry Standards as Institutional Barriers to More Sustainable Concrete Bridge Infrastructure
Authors: Arbuckle Peter W. , Lepech Michael D. , Keoleian Gregory A.
Published: June 2014

The concrete construction industry is governed by a network of codes and standards that ensure safety and quality. This study evaluates two central concrete construction industry standards related to bridge construction to determine if these standards inhibit more sustainable concrete bridge construction. Using social networking tools, ASTM C150-05: Standard Specification for Portland Cement and American Concrete Institute (ACI) 211.1-91/09 Standard Practice for Proportioning Normal, Heavyweight, and Mass Concrete, were identified as “central” concrete industry standards and were evaluated to test whether central concrete industry standards pose institutional barriers to innovation for sustainable concrete construction. Results indicate that while these standards do not explicitly inhibit more sustainable concrete practice, the manner in which they are used implicitly impedes more sustainable concrete construction and innovation for sustainability. Specifically, ASTM C150-05 does not inhibit the use of cement materials with lower environmental impact, but industry demand for rapid construction and institutionalized use of C150-05 to the exclusion of other environmentally preferable products does inhibit more sustainable concrete construction. Similarly, mixes designed for durability using performance-based specifications exhibit reduced annual energy and material impacts compared to mixtures traditionally designed using ACI 211.1-91/09.
Strain Gradients in Concrete Affected by Alkali–Silica Reaction: A Laboratory Simulation
Authors: Giannini Eric R. , Bentivegna Anthony F. , Folliard Kevin J.
Published: June 2014

Alkali–silica reaction (ASR) is a significant durability issue that has resulted in expansion and cracking of numerous concrete structures. Expansion is often not uniform in a given structure, leading to the development of strain gradients and manifested in macrocracking patterns on the surface. Techniques developed to mitigate ASR in existing structures involving surface treatments, such as lithium impregnation or silanes, can cause strain gradients to develop by suppressing expansion in the near-surface region, while expansion in the center of the concrete continues uninhibited. A set of plain concrete slabs consisting of a layer of ASR-resistant concrete with lithium nitrate admixture cast over a layer of ASR-susceptible concrete were monitored for expansion and crack development. The study found that a layer of ASR-resistant concrete of at least 50 mm (2.0 in.) deep was necessary to significantly suppress expansion and cracking at the top surface. However, in all layered specimens, the bottom layer continued to expand and a significant strain gradient developed between the top and bottom surfaces.
Stribeck-Type Curves of Alternative Engine Oils: Part I: Gray Cast Iron Liners
Authors: Woydt Mathias , Kelling Norbert , Hannemann Falk , Berberich Niklas , Ziegele Holger
Published: June 2014

Wear tests are often used in engine development in order to characterize the functional profile of surfaces interacting with lubricants. This paper proposes a new test procedure to determine Stribeck-type curves for the tribosystem piston ring/cylinder liner involving test pieces prepared from engine components. The variation of the friction coefficient with sliding speed depends on the structure and constitution of the base oil, the viscosity index, the surface topography of the liner and ring, and the friction modifiers used. Novel organic friction modifiers of low molecular mass not only reduce the friction coefficients under mixed / boundary lubrication, but also in the fluid film regime. In addition, the influence of surface roughness on the wettability of surfaces can be significant for both static and dynamic wetting. For this reason, the interaction of the lubricant with the surfaces was also investigated to enable a correlation between the surface properties of the liquid and solid phases and the tribological behavior.
Effect of Hardfacing Processes on Ballistic Performance of Q&T Steel Joints
Authors: Balakrishnan M. , Balasubramanian V. , Madhusudhan Reddy G.
Published: June 2014

This study was carried out to evaluate the effect of hardfacing processes on the ballistic performance of armour grade quenched and tempered (Q&T) steel welded joints. Two joints were fabricated using 4 mm thick tungsten carbide (WC) hardfaced middle layer, above and below which austenitic stainless steel (SS) layers were deposited on both sides of the hardfaced interlayer. Plasma transferred arc (PTA) hardfacing and shielded metal arc (SMA) hardfacing processes were used to deposite WC interlayer. In both joints, SS layers were deposited by shielded metal arc welding (SMAW) process. The fabricated joints were tested for its ballistic performance and the results were compared with respect to depth of penetration (DOP) on weld metal and HAZ locations. From the ballistic test results, it is observed that both the joints successfully stopped the bullet penetration at weld center line. Of the two joints, the joint made with SMA hardfacing offered a maximum resistance to the bullet penetration with a DOP of 16 mm without any bulge at the rear side of the weld center line. The gradual increment in hardness in the front layer is the primary reason for the successful intact of the bullet with a lesser depth of penetration.
Effect of Process Parameters on the Microstructures and Mechanical Properties of Iso-Thermally Treated Ductile Iron
Authors: Atanda P. O. , Olorunniwo O. E. , Imasogie B. I.
Published: June 2014

The effect of process parameters on the mechanical properties of iso-thermally treated ductile irons was investigated in this study. Sets of ductile irons produced by sandwich method from a rotary furnace melt were given iso-thermal austempering treatments using commercial neutral salt baths. The samples were preheated at 350°C and held for 1 h in a muffle furnace, followed by ausenitizing in an ausenitizing salt bath furnace containing a mixture of BaCl2 and NaCI, (in the ratio 3:2) at 900°C and soaking at that temperature for 1 h. The samples were immediately transferred to the austempering salt bath furnace containing a mixture of NaNO3 and KNO2 in the ratio 1:1. Sets of the samples were soaked at 300°C for between 5 to 240 min and were all later cooled in air. The austempering procedure was repeated at 350 and 400°C for a second and third groups of samples, respectively. The results showed that austempering at lower temperature (300°C) produced a relatively high tensile strength of 1400 MPa, after 150 min holding compared with austempering at the higher temperature (400°C) which produced a relatively lower strength of 1200 MPa at the same holding time. However, the optimal processing window for the austempering was established to be the intermediate temperature of 350°C after a holding time of 150 min. At this processing window, austempering yielded the optimum combination of mechanical properties of 1502 MPa UTS, 7.5 % elongation, and impact energy of 108 J. These properties correspond to a microstructure consisting of a plate-like morphology of ausferrite and retained austenite.
Erosion Wear Characteristics of Surface Modified Grey Cast Iron by WC–Co–Cr/NiCrBSi Coating Using HVOF Thermal Spray Process
Authors: Yoganandh J. , Natarajan S. , Kumaresh Babu S. P.
Published: June 2014

Pump casings made of grey cast iron (GCI) used in lignite mines for dewatering are subjected to erosive wear and fail catastrophically. An attempt was made to modify the surface of GCI by WC–Co–Cr/NiCrBSi coating using HVOF process for the application under mining conditions. Grey cast iron samples with and without WC–Co–Cr/NiCrBSi coating were subjected to slurry jet erosion tests by varying the impingent velocity and angle under two different pH conditions of 3 and 7 which pertain to the mining environment. XRD characterization was done to identify and confirm phase composition. Eroded surface morphology studies were carried by SEM on both the substrate and coating, which revealed the erosion of GCI surface, predominantly due to ploughing mechanism. In the case of WC–Co–Cr and NiCrBSi coating, at an oblique angle of impact, the material removal from the surface is by micro cutting of the matrix, ploughing, and abrasive mode mechanisms. At normal impingement, the fluctuating stress creates the cracks, which interlink each other to form lips and craters followed by material degradation through fatigue. Performance of WC–Co–Cr coating is found to be better than NiCrBSi Coating.
Multi-rate and Multi-modal Characterization of an Advanced Poly(etherimide): Ultem 1000
Authors: Zuanetti Bryan , Mutter Nathan , Gordon Ali P.
Published: June 2014

The key to the effective implementation of polymers in structural applications is an understanding of the mechanical response under a variety of conditions. In this study, an unreinforced poly(etherimide) (PEI) known as Ultem 1000 was characterized under quasi-static and high-strain-rate loading. Standard tension, compression, and torsion experiments were conducted in order to investigate the multi-regime response of this material. The elastic response of the material to multiple loading conditions was correlated using the Ramberg–Osgood model. The effects of thermal and mechanical rejuvenation processes on the mechanical response were investigated; the upper yield strength of the material was reduced, and the strain softening regime responsible for strain localization was largely eliminated. The fracture toughness of the material was evaluated using a Charpy impact test, and the mechanisms of failure were shown to be brittle. The high-strain-rate response of the material to uniaxial compression was evaluated by means of a miniaturized split Hopkinson pressure bar, and the strain-rate dependence of the material was modeled using the Ree–Eyring equations. Finally, a combination of the Ramberg–Osgood model and a novel model was employed to correlate the elastoplastic response of rejuvenated PEI to quasi-static mechanical loading.
Macrophages and β‐cells are responsible for CXCR2‐mediated neutrophil infiltration of the pancreas during autoimmune diabetes
Authors: Diana Julien , Lehuen Agnès
Published: June 2014

Autoimmune type 1 diabetes (T1D) development results from the interaction between pancreatic β‐cells, and the innate and the adaptive immune systems culminating with the destruction of the insulin‐secreting β‐cells by autoreactive T cells. This diabetogenic course starts during the first postnatal weeks by the infiltration of the pancreatic islets by innate immune cells and particularly neutrophils. Here, we aim to determine the cellular and molecular mechanism leading to the recruitment of this neutrophils in the pancreatic islets of non‐obese diabetic (NOD) mice. Here, we show that neutrophil recruitment in the pancreatic islets is controlled by inflammatory macrophages and β‐cells themselves. Macrophages and β‐cells produce the chemokines CXCL1 and CXCL2, recruiting CXCR2‐expressing neutrophils from the blood to the pancreatic islets. We further show that pancreatic macrophages secrete IL‐1β‐inducing CXCR2 ligand production by the β‐cells. Finally, the blockade of neutrophil recruitment at early ages using CXCR2 antagonist dampens the diabetogenic T‐cell response and the later development of autoimmune diabetes, supporting the therapeutic potential of this approach.
A case of pituitary apoplexy in pregnancy
Authors: Hayes Aimee R , O'Sullivan Anthony J , Davies Mark A
Published: June 2014

Pituitary apoplexy is a rare event in pregnancy. A 41-year-old woman with a known pituitary microadenoma presented with visual disturbance and headache during the second trimester of pregnancy. Magnetic resonance imaging (MRI) demonstrated pituitary apoplexy with chiasmal compression. After treatment with corticosteroid therapy, she underwent transsphenoidal excision of the pituitary adenoma. Visual abnormalities were completely restored and pituitary function preserved. There was no evidence of impact on the foetus. The literature on the subject is reviewed with emphasis on the management of the apoplectic patient with mild and stable neuro-ophthalmological signs.

Learning points

There are no clear guidelines on the management of pituitary apoplexy in pregnancy. A multidisciplinary approach can minimise morbidity and mortality.

Pituitary apoplexy has an unpredictable clinical course and determining which clinical situations warrant early surgery needs to take into consideration the presence and severity of neurological signs and their stability.

The management of conscious apoplectic patients with absent or mild and stable neuro-ophthalmological signs is controversial.
The Effects of Varying Chromosome Arm Dosage on Maize Plant Morphogenesis
Authors: Brunelle Dale C , Sheridan William F
Published: June 2014

Maize is an especially well-suited species for studying the effects of aneuploidy on plant development. We used B-A translocations and testers that were crossed seven times into inbred W22 to generate a dosage series for 14 chromosome arms. This is the first report of dosage effects on maize morphogenesis using inbred B-A stocks and inbred tester stocks. We compared plants containing one dose or three doses of each of the 14 chromosome arms with plants containing two doses for seven measured traits. These were leaf width, leaf length, plant height, ear height, internode length, ear node circumference, and tassel branch number. We observed the typical maize aneuploid syndrome wherein one dose was more widespread and more severe in its effects than three doses. All but two of the one-dose effects were negative, and all of the three-dose effects were negative. The occurrence of positive responses by hyperploid plants in our earlier B-A-A study and the absence of any positive responses among the hyperploids reported for the 14 simple B-A translocations tested for dosage effects in the present study and previously may reflect gene dosage interaction between the two chromosome arm segments present in the B-A-A translocations. The overall congruence of our results with those of previous studies suggests that the traits measured are quantitative traits controlled by multiple genes whose activities provide a balanced regulation that transcends individual inbred lines or diverse genetic backgrounds and that such genes may be especially abundant in chromosome arm 1L.
Ablation of Arrhythmias in Patients with Adult Congenital Heart Disease
Authors: Lobo Rodrigo Gallardo , Griffith Michael , De Bono Joseph ,   Senior Fellow in Electrophysiology,   Consultant Cardiologist, Queen Elizabeth Hospital, Birmingham, UK,   Consultant Cardiologist, Queen Elizabeth Hospital, Queen Elizabeth Medical Centre, Birmingham B15 2TH, UK. E: Joseph.DeBono@uhb.nhs.uk
Published: June 2014

Arrhythmias in adults with congenital heart disease, most commonly related to previous surgical procedures, are a frequent comorbidity in this growing population thanks to the improved outcome of surgical techniques. Re-entrant circuits around areas of scarring and natural barriers, combined with abnormal haemodynamics and the underlying anatomy, are the most common cause for these arrhythmias. They are often poorly tolerated and medical treatment is frequently inadequate. In recent years, catheter ablation has emerged as a successful therapeutic option. New advanced techniques such as the use of modern three-dimensional (3D) navigation systems have contributed to better understanding of the arrhythmia mechanisms and higher success rates of the ablation procedures. In this article we briefly summarise the characteristics of the most common arrhythmias in this patient population and some key aspects in their treatment by catheter ablation.
Current Antithrombotic Therapy in Patients with Acute Coronary Syndromes Undergoing Percutaneous Coronary Interventions
Authors: Pesarini Gabriele , Ariotti Sara ,   Division of Cardiology, Department of Medicine, University of Verona, Italy, University of Verona, Piazzale Aristide Stefani 1, 37126, Verona, Italy. E: gabriele.pesarini@ospedaleuniverona.it,   Division of Cardiology, Department of Medicine, University of Verona, Italy,   Division of Cardiology, Department of Medicine, University of Verona, Italy
Published: June 2014

Acute coronary syndromes (ACS) represent a life-threatening complication of the systemic atherosclerotic process, affecting the coronary circulation. Thrombosis, defined as an uncontrolled activation of the endogenous thrombogenetic reparative process, often follows atherosclerotic plaque damage and is mainly engaged by two main pathways: platelet aggregation and coagulation. Therefore, antithrombotic therapy to modulate either pathway plays an important role for the reduction of ischaemic adverse events in ACS patients. Since the advent of aspirin and warfarin, numerous antiaggregant and anticoagulant molecules have been developed to achieve this goal, but their anti-ischaemic efficacy is often obtained at the price of augmented bleedings, which are known to be strong predictors of adverse outcome. This article briefly reviews the physiopathological mechanisms of thrombosis and presents an overview of the available literature supporting the use of these major drugs, as well as the European Society of Cardiology recommendations for their utilisation in the setting of non-ST and ST-elevation myocardial infarction undergoing invasive treatment.
Clinical Impact of Stent Design
Authors: Noad Rebecca L , Hanratty Colm G , Walsh Simon J ,   Specialist Registrar in Cardiology,   Consultant Cardiologist, Belfast City Hospital, Belfast Health and Social Care Trust, Belfast, Northern Ireland, UK,   Consultant Cardiologist, Belfast City Hospital, Belfast Health and Social Care Trust, Belfast, Northern Ireland, UK, 51 Lisburn Road, Belfast, BT9 7AB, Northern Ireland, UK. E: simon.walsh@belfasttrust.hscni.net
Published: June 2014

The introduction and widespread adoption of drug-eluting stents into routine clinical practice has seen tremendous changes in the practice of interventional cardiology. For a prolonged period, manufacturers have focused research on drugs and polymers that are the key to the prevention of in-stent restenosis. However, stent platform design and its clinical implications have now come back to the fore. This has occurred for numerous reasons, but has primarily been driven by the need for modern stents to perform well in increasingly demanding clinical scenarios. This paper reviews the historical evolution of stent platform design. Current manufacturing processes and materials are also explored. Geometric stent construction and its implications for longitudinal stability and the longer term risks of stent fracture are reviewed. Finally, the implications of the specific stent chosen for different clinical applications including the treatment of bifurcations and left main disease are also summarised. This article will familiarise cardiologists with the crucial impact of each of these factors on modern day practice, as well as acute and long-term outcomes for patients.
Review of Data and Discussion – Who Should Undergo Patent Foramen Ovale Closure in 2014?
Authors: Bhan Amit , Clapp Brian ,   Department of Cardiology, Guy’s and St Thomas’ Hospital, London, UK,   Department of Cardiology, Guy’s and St Thomas’ Hospital, London SE1 7EH, UK. E: brian.clapp@gstt.nhs.uk
Published: June 2014

A patent foramen ovale is a relatively common finding in the general population and is associated with a number of conditions, including cryptogenic stroke. In 2014, percutaneous patent foramen ovale (PFO) closure is a frequently performed procedure; the bulk of these procedures being carried out for secondary prevention of cryptogenic stroke, along with other indications, such as prevention of decompression illness, platypnoea-orthodeoxia syndrome and migraine. Of these conditions the largest body of evidence available is for cryptogenic stroke and there is ongoing debate of the benefit of PFO closure over medical therapy. This article will review the available evidence of PFO closure in each of these contexts, with a particular focus on randomised controlled trials, and endeavour to outline in whom the evidence suggests closure should be considered.
Use of Thrombectomy Devices in Primary Percutaneous Interventions for ST-elevation Myocardial Infarction – An Update
Authors: Rathod Krishnaraj S , Hamshere Stephen M , Choudhury Tawfiq R , Jones Daniel A ,   Department of Cardiology, Barts Health NHS Trust; Department of Clinical Pharmacology, William Harvey Research Institute, Queen Mary University, London; NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London,   Department of Cardiology, Barts Health NHS Trust; NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London,   Department of Cardiology, Barts Health NHS Trust; Department of Clinical Pharmacology, William Harvey Research Institute, Queen Mary University, London; NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London,   Department of Cardiology, Barts Health NHS Trust; Department of Clinical Pharmacology, William Harvey Research Institute, Queen Mary University, London; NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London,   Department of Cardiology, Barts Health NHS Trust; Department of Clinical Pharmacology, William Harvey Research Institute, Queen Mary University, London; NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, Bonner Road, Bethnal Green, London E2 9JX. E: a.mathur@qmul.ac.uk
Published: June 2014

Primary percutaneous coronary intervention (PPCI) is the preferred reperfusion modality in patients with ST-elevation myocardial infarction (STEMI). While PPCI is highly effective in achieving epicardial coronary reperfusion, a significant proportion of patients fail to achieve adequate myocardial reperfusion. This is in part due to the distal microembolisation of thrombus and plaque debris during PCI. Recognition of this has led to the development of a number of devices with different mechanisms of action that aim to reduce such distal embolisation and therefore improve end myocardial perfusion. Study results of thrombectomy devices however have been largely inconsistent, especially about clinical outcome data, and several meta-analyses have been carried out as a result. This review aims to critically analyse the literature data on thrombectomy during PPCI, taking into account the most recent studies and the latest metaanalyses looking to see whether thrombectomy use is associated with improved outcomes.
Differences in Outcomes and Indications between Sapien and CoreValve Transcatheter Aortic Valve Implantation Prostheses
Authors: Noorani Alia , Bapat Vinayak ,   Department of Cardiothoracic Surgery, Papworth Hospital, Cambridge,   Consultant Cardiothoracic Surgeon, Department of Cardiothoracic Surgery, St. Thomas’ Hospital, London SE1 7EH, UK. E: vnbapat@yahoo.com
Published: June 2014

Transcatheter aortic valve implantation (TAVI) has emerged as a suitable alternative to surgical valve replacement for patients with severe, symptomatic, calcified aortic stenosis and a background of co-morbidities, which can make surgery a high-risk option. It has also evolved as an alternative for degenerative prosthetic heart valve disease. Since the inception of TAVI in 2002, the two main devices in routine clinical use are the Edwards Sapien valve (since 2006) and the Medtronic CoreValve (since 2007). The more recent Sapien XT valve and Sapien 3 have been in clinical use since 2010 and 2013, respectively. In addition to registry data on these devices, there are a number of completed and ongoing randomised controlled trials, including one comparing the two devices. The aim of this article is to discuss the differences in indications and outcomes between these two prostheses.
The Role of Self-expanding Stents in Patients with Atypical Coronary Anatomy
Authors: van Geuns Robert-Jan , Awad Katherin , IJsselmuiden Alexander , Koch Karel ,   Interventional Cardiologist, Erasmus Medical Centre, Thoraxcentrum, Department Cardiology, Postbus 2040, 3000 CA Rotterdam, The Netherlands. E: r.vangeuns@erasmusmc.nl,   Medical Affairs, STENTYS SA, Paris, France,   Albert Schweitzer Ziekenhuis, Dordrecht, The Netherlands,   Academisch Medisch Centrum, Amsterdam, The Netherlands
Published: June 2014

Despite advances with new generation stents, there remains some atypical coronary anatomy where optimal stenting continues to be a challenge; such as stent sizing in large, ectatic or aneurysmal vessels; tapered vessels; and in vasoconstricted arteries such as in ST-segment elevation myocardial infarction or chronic total occlusions. Balloon-expandable stents are tubular and cannot easily accommodate vessel diameter variations; thrombotic vessels increase the risk of distal embolisation and no-reflow; positive remodelling and vasodilation often result in subsequent malapposition; and patients with bifurcation lesions have a higher risk of adverse events. The STENTYS BMS and DES(P)stents have a self-expanding design, which enables a better anatomical fit to the vessel, even with diameter variations (up to 6.0 millimetres [mm]), and can adapt to changes in vessel size over time. The stents deploy atraumatically from distal to proximal, which could reduce distal embolisation and contain disconnectable bridges, which can be opened up at a side branch. Self-apposing technology could therefore provide a potential solution to current challenges with balloon-expandable stent technology.
Overview of Technical and Cost Considerations in Complex Percutaneous Coronary Intervention
Authors: Estrada J Raider , Paul Jonathan D , Shah Atman P , Nathan Sandeep ,   University of Chicago Medicine, Section of Cardiology, Chicago, Illinois, US,   University of Chicago Medicine, Section of Cardiology, Chicago, Illinois, US,   University of Chicago Medicine, Section of Cardiology, Chicago, Illinois, US,   Associate Professor of Medicine, University of Chicago Medicine, 5841 South Maryland Ave, MC 5076, Chicago, IL 60637. E: snathan@medicine.bsd.uchicago.edu
Published: June 2014

Complex percutaneous coronary intervention (PCI), encompassing an ever-expanding range of challenging lesion sets and patient populations, accounts for a significant proportion of PCI procedures being performed currently. Specific lesion types associated with lower rates of procedural success and higher rates of recurrence or major adverse cardiac events (MACE) include multivessel disease, unprotected left main coronary artery disease, fibrocalcific or undilatable lesions, chronic total occlusions, degenerated saphenous vein graft lesions, thrombotic lesions, and bifurcation disease. Validated tools and technical strategies currently exist to address most procedural scenarios encountered and should be familiar to the complex PCI operator. Anticipated clinical outcomes, projected resource utilization, and cost considerations should all factor into the decisions of when, how, and in whom to intervene.
Surgical Approaches to Aortic Valve Replacement and Repair—Insights and Challenges
Authors: Ramlawi Basel , Ramchandani Mahesh , Reardon Michael J ,   Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital, Houston, Texas, US,   Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital, Houston, Texas, US,   Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital, Houston, Texas, US. E: MReardon@houstonmethodist.org
Published: June 2014

Since 1960, surgical aortic valve replacement (sAVR) had been the only effective treatment for symptomatic severe aortic stenosis until the recent development of transcatheter aortic valve replacement (TAVR). TAVR has offered an alternative, minimally invasive treatment approach particularly for patients whose age or co-morbidities make them unsuitable for sAVR. The rapid and enthusiastic utilization of this new technique has triggered some speculation about the imminent demise of sAVR. We believe that despite the recent advances in TAVR, surgical approach to aortic valve replacement has continued to develop and will continue to be highly relevant in the future. This article will discuss the recent developments and current approaches for sAVR, and how these approaches will keep pace with catheter-based technologies.
Transcatheter Aortic Valve Replacement in Moderate-risk Aortic Stenosis Patients
Authors: Svensson Lars G ,   Department of Cardiothoracic Surgery, Aorta Center and Heart and Vascular Institute, Cleveland Clinic, 9500 Euclid Ave/Desk J4-1, Cleveland, OH 44915, US. E: svenssl@ccf.org
Published: June 2014

The Placement of Aortic Transcatheter Valves (PARTNER) trial showed the effectiveness of transcatheter aortic valve replacement (TAVR) for inoperable patients and non-inferiority for mortality versus open valve replacement. There are three questions concerning the role of TAVR for intermediate-risk patients. These relate to: institutional and surgeon results, physician and hospital alignments, and who will pay.
Renal Sympathetic Denervation – A Review of Applications in Current Practice
Authors: Kapil Vikas , Jain Ajay K , Lobo Melvin D ,   William Harvey Heart Centre, NIHR Cardiovascular Biomedical Research Unit, Centre for Clinical Pharmacology, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK; Barts Hypertension Clinic, Department of Clinical Pharmacology, Barts Health NHS Trust, London, UK,   William Harvey Heart Centre, NIHR Cardiovascular Biomedical Research Unit, Centre for Clinical Pharmacology, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK; Department of Cardiology, London Chest Hospital, Barts Health NHS Trust, London, UK,   William Harvey Heart Centre, NIHR Cardiovascular Biomedical Research Unit, Centre for Clinical Pharmacology, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ. E: m.d.lobo@qmul.ac.uk; Barts Hypertension Clinic, Department of Clinical Pharmacology, Barts Health NHS Trust, London, UK
Published: June 2014

Resistant hypertension is associated with high morbidity and mortality despite numerous pharmacological strategies. A wealth of preclinical and clinical data have demonstrated that resistant hypertension is associated with elevated renal and central sympathetic tone. The development of interventional therapies to modulate the sympathetic nervous system potentially represents a paradigm shift in the strategy for blood pressure control in this subset of patients. Initial first-in-man and pivotal, randomised controlled trials of endovascular, radio-frequency renal sympathetic denervation have spawned numerous iterations of similar technology, as well as many novel concepts for achieving effective renal sympatholysis. This review details the current knowledge of these devices and the evidence base behind each technology.
Uralkodói propaganda Ioachimus Vadianus Mela-kommentárjában
Authors: Bobay Orsolya
Published: June 2014

Joachim von Watt (Ioachimus Vadianus) kommentárja, amely az első tudományos igényű Mela-kommentárnak tekinthető, elsőként 1518-ban jelent meg. Előzményének Ermolao Barbaro velencei humanista Castigationes Plinianae et in Pomponium Melam című filológiai kommentárját tekinthetjük. A lemmák vizsgálata során az ókori és a kora újkori uralkodóportrék két csoportját különíthetjük el, a jó és a rossz királyokét, illetve császárokét. A kommentárnak ez az olvasata az antik mű új tartalommal való felruházására irányuló törekvést példázza, amelynek során a lemmaíró Vadianus a korabeli olvasó számára hasznos ismereteket kíván közvetíteni. Ez az olvasat Vadianus későbbi munkájában, a Sankt Gallenben írt Epitome trium terrae partiumban már nem jelenik meg, ami bizonyítja a kommentár uralkodóképében rejlő propagandisztikus célokat. A rossz és jó uralkodók legkiemelkedőbb példái Nagy Sándor és I. (Jagelló) Zsigmond, a többi uralkodó e két pólus között helyezkedik el. Az ókor rossz uralkodóinak bemutatásakor Vadianus az ókori toposzokat követi: olvashatunk Neróról és Caliguláról, de a lemmákban rossz uralkodóként szerepel a késő római Pertinax császár is. A helvét humanista utóbbit erkölcsi szempontból ítéli el, bár a Historia Augusta leírásában nem szerepelnek az általa leírt morális aspektusok. Az antikvitás jó uralkodói, Antoninus Pius és Marcus Aurelius is erkölcsi szempontból kiemelkedőek Vadianus számára, azonban a modern uralkodók tekintetében a morális jó tulajdonságok mellett a hadi jártasság is a jó uralkodó ismérve. Véleménye szerint a jó uralkodó képes a kettőt összeegyeztetni egymással, és emellett emberi vonásait is megőrizni, ahogy I. Miksa és I. Zsigmond is.
Fundamental insight into control of thermal conductivity in silicon-germanium alloy nanowires
Authors: Lee Yongjin , Hwang Gyeong S.
Published: June 2014

We present a computational analysis of thermal transport in Silicon-Germanium alloy nanowires (SiGeNWs), particularly focusing on the relative roles of alloy scattering and boundary scattering to the significant reduction of thermal conductivity (κ). Our nonequilibrium molecular dynamics (NEMD) simulations confirm the strong dependence of κ on Si:Ge ratio, as observed in previous experimental studies. Interestingly, as the amount of impurity increases, the difference in κ between SiGe bulk and SiGeNW becomes smaller. Especially, κSiGeNW and κSiGe have similar κ values when the Ge content is 20-80 %. From a nonequilibrium Green’s function (NEGF)-density functional theory (DFT) analysis, it is suggested that the most reduction in transmission channels is attributed to the strong alloy scattering effect for both Si0.8Ge0.2 bulk and Si0.8Ge0.2 NW. The boundary scattering effect in the SiGe alloy system seems to be unimportant as alloy scattering is dominant. The improved understanding provides fundamental insight into how to modify Si-based materials to enhance their thermoelectric (TE) properties through nanostructuring and alloying.
Quantitative Electron Diffraction from Thin Films
Authors: Lagally M.G. , Savage D.E.
Published: June 2014

The structure and morphology of a thin film is, apart from composition, probably its most significant feature. Again and again we find that electronic, chemical, mechanical, magnetic, optical, and superconducting properties depend on the arrangement of atoms and on disorder in this arrangement. As most thin films are created using some form of deposition technique in which atoms are brought together at a surface, it is at the surface that the first opportunity occurs for formation of a particular atomic structure and morphology. As deposition proceeds, a moving surface, the “growth front,” continues to serve as the template for structure formation. Various kinetic processes, such as atomic transport and the adsorption or desorption of atoms from already-formed structures, determine the final morphology of the film. Subsequent treatment can, of course, modify the structure and morphology, but clearly the initial events occurring at the surface influence, to a large measure, the final outcome.

Techniques sensitive to surface structure and morphology are therefore an important component in the toolbox of methods for the quantitative analysis of the properties of thin films. Electron diffraction techniques have been, and continue to be, the most powerful and versatile of these. Even though electron diffraction is also useful for the structural analysis of the bulk, when one speaks of electron diffraction in the context of thin films, one almost invariably refers to surface-sensitive diffraction. Other methods, in particular scanning probe microscopy, have recently become popular. In many cases, such methods serve to re-emphasize the value of electron diffraction for quantitative structural analysis of thin films.
Mapping Invasive Plant Distributions in the Florida Everglades Using the Digital Aerial Sketch Mapping Technique
Authors: Rodgers LeRoy , Pernas Tony , Hill Steven D.
Published: June 2014

The management of exotic, invasive plants is among the most challenging undertakings of natural resource managers, particularly in large, remote landscapes. The availability of information on the distribution and abundance of invasive plants is vital for effective strategic planning yet is often unavailable because of high costs and long procurement times. This paper presents results of a large-scale invasive plant mapping effort in the Florida Everglades utilizing digital aerial sketch mapping (DASM) and evaluates its utility for guiding management decisions. The distribution and abundance (cover) of four priority invasive plant species—Australian pine, Brazilian pepper, melaleuca, and Old World climbing fern—were mapped over 728,000 ha in the Everglades during 2010 to 2012. Brazilian peppertree was the most widely distributed and abundant species, occupying 30,379 ha. Melaleuca was also widely distributed and occupied 17,802 ha. Old World climbing fern occupied only 7,033 ha but its distribution was generally concentrated in heavy infestations in the northern Everglades. Australian pine was the least abundant of the mapped species and tended to be limited to the southeastern Everglades region. DASM proved to be a cost-effective means of obtaining region-wide distribution and abundance information for these species at broad scales (> 500 m), but detection rates and positional accuracy declined at finer scales. Both canopy type (forested vs. unforested) and distance from flight transect appear to be important factors for detection accuracy.
Restoration of Exotic Annual Grass-Invaded Rangelands: Importance of Seed Mix Composition
Authors: Davies Kirk W. , Johnson Dustin D. , Nafus Aleta M.
Published: June 2014

Restoration of exotic annual grass-invaded rangelands is needed to improve ecosystem function and services. Increasing plant species richness is generally believed to increase resistance to invasion and increase desired vegetation. However, the effects of species richness and individual plant life forms in seed mixes used to restore rangelands invaded by exotic annual grasses have not been investigated. We evaluated the effects of seeding different life forms and increasing species richness in seed mixes seeded after exotic annual grass control to restore desirable vegetation (perennial herbaceous vegetation) and limit exotic annual grasses at two sites in southeastern Oregon. We also investigated the effects of seeding two commonly used perennial grasses individually and together on plant community characteristics. Large perennial grasses, the dominant herbaceous plant life form, were the most important group to seed for increasing perennial herbaceous vegetation cover and density. We did not find evidence that greater seed mix species richness increased perennial herbaceous vegetation or decreased exotic annual grass dominance more than seeding only the dominant species. None of the seed mixes had a significant effect on exotic annual grass cover or density, but the lack of a measured effect may have been caused by low annual grass propagule pressure in the first couple of years after annual grass control and an unusually wet-cool spring in the third year post-seeding. Although our results suggest that seeding only the dominant plant life form will likely maximize plant community productivity and resistance to invasion in exotic annual grass-invaded northern Great Basin arid rangelands, seeding a species rich seed mix may have benefits to higher tropic levels and community stability. Clearly the dominant species are the most prudent to include in seed mixes to restore exotic annual grass-invaded plant communities, especially with finite resources and an increasingly large area in need of restoration.
Landscape-Level Simulation of Weed Treatments to Evaluate Treatment Plan Options
Authors: Aracena Pablo , Chung Woodam , Jones Greg
Published: June 2014

Models have been developed to simulate the long-term effects of weed treatments across a landscape to determine effective management strategies, but those models might not be suitable for evaluating short-term action plans of weed treatments that are specific in time and place. In this study, we developed a simulation model to build and evaluate 5-yr weed treatment plan options in terms of their cost and effectiveness in minimizing total infestation areas over the short-term planning horizon. In an iterative, interactive process, 5-yr treatment plan options are developed based on user-defined weed treatment preferences, and evaluated in terms of total projected infestation areas at the end of the planning horizon. The simulation model was applied to a study area of 24,867 ha (61,447 ac) located in the Salmon River watershed in Idaho. Eight treatment plan options were developed using two treatment priority strategies and four increasing budget levels, and compared for their effectiveness. The application results showed that regardless of budget levels, site priority strategies were more cost-effective than the species priority strategies in reducing total infestation areas over time. This simulation model can provide weed managers with a useful tool to evaluate short-term treatment options, and thus support informed decision-making for effective weed management. Although the availability and quality of input data may be a practical limitation of using the simulation model, more data would become available and improved as more invasive species monitoring programs are implemented.
Efficacy of Several Herbicides on Yellow Archangel (Lamiastrum galeobdolon)
Authors: Miller Timothy W. , Halpern Alison D. , Lucero Frances , Shaw Sasha H.
Published: June 2014

Yellow archangel is a twining perennial species that produces a dense evergreen canopy and may negatively affect forest floor vegetation. Because it is spreading rapidly in the Pacific Northwest (PNW), greenhouse and field trials were conducted on yellow archangel to determine its relative sensitivity to several herbicides. Products that slowed or prevented yellow archangel regrowth at 9 mo after treatment (MAT) in one or both iterations of the greenhouse trial were aminopyralid, diclobenil, glufosinate, imazapyr, isoxaben, metsulfuron, sulfometuron, triclopyr amine, and triclopyr ester + 2,4-D ester. In the field trial at 10 MAT, triclopyr and imazapyr were controlling 81 and 78% of treated yellow archangel, respectively, similar to aminopyralid, glyphosate, and metsulfuron (61 to 65%). Two applications of 20% acetic acid or 20% clove oil were controlling 53% at the same timing. At 13 MAT, only imazapyr and glyphosate were still providing good control of yellow archangel (81 and 80%, respectively), while all other products were controlling the weed at 53% or less. By 7 or 8 MAT after a second application, only imazapyr and glyphosate provided effective control of yellow archangel (86 to 94%).
Herbicides for Postemergence Control of Mile-a-Minute (Mikania micrantha)
Authors: Sellers Brent A. , Lancaster Sarah R. , Langeland Kenneth A.
Published: June 2014

Greenhouse experiments were conducted to evaluate mile-a-minute response to selected herbicides. In the first experiment, mile-a-minute response was evaluated following the application of aminocyclopyrachlor, aminopyralid, fluroxypyr, glufosinate, glyphosate, imazamox, imazapic, metsulfuron, penoxsulam, and triclopyr. Applications of aminocyclopyrachlor, aminopyralid, fluroxypyr, glufosinate, glyphosate, and triclopyr all resulted in mile-a-minute control 70% or greater 8 wk after treatment (WAT). Mile-a-minute sensitivity to these six herbicides was further evaluated in a dose-response study. Although 90% growth reduction (GR90) values were determined for aminopyralid and glyphosate, statistically significant results were not obtained for aminocyclopyrachlor, fluroxypyr, glufosinate, and triclopyr. The results of these experiments suggest that glyphosate, as well as the synthetic auxin herbicides aminocyclopyrachlor, aminopyralid, fluroxypyr, and triclopyr, should be further evaluated for mile-a-minute control in south Florida.