bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging of Backscattered Ionizing Radiation - A Key Enabler for through Mud Borehole Imaging
Authors: Teague Philip Neil
Published: May 2011

Current technology offers the operators of well-intervention equipment little opportunity to receive accurate and real-time visual feedback from the borehole when the fluid contents are opaque. As a result, the majority of operations are performed 'blind' leading to extensive use of time and increased risk of material damages. In extreme cases, and in the pursuit of a clear image the well's contents must be displaced and replaced with fluids that offer better visibility for video cameras at the possible expense of well integrity.

Previous work within the field of borehole imaging has focused upon optical cameras, ultrasound and millimeter-wave technologies. Ionizing radiation is not perturbed by the optical opacity of the well contents or refracted and distorted by flowing fluids. The paper provides detailed results of data gathered from laboratory and field testing. In addition, the paper illustrates images of objects located in a drilling-fluid-filled well. The information provided offers an overview of a new technology and method, which solves the issues surrounding in-hole imaging of infrastructure, well-integrity inspection, and lost or stuck items without the need to displace the well contents.

An overview of the development efforts involving the creation of a borehole tool which aims to solve the issue of through mud imaging, or imaging in a producing well without the need to displace the current contents to an optically clear fluid. The paper gives an overview of the steps necessary to mitigate the risk of such a development project, and an overview of the most important lessons learned. Imaging of backscattered ionizing radiation can find applications within well integrity inspection, perforation inspection, well auditing and the location and orientation of lost or stuck items within the borehole.

Introduction

One of the major financial concerns voiced by the drilling industry is lost time due to unplanned events such as items lost or stuck downhole in addition to well integrity issues. A number of companies have launched a series of major initiatives that have seen the number of such incidents fall substantially; however, the problem has not been completely possible to eradicate (Fowler, 1996).

Drill string or a downhole tool stuck in a well can prove to be expensive, not only due to possible material damages but due to lost time. Not only are the increasingly sophisticated array of downhole tools and the time lost using them costly, but also the inability to retrieve them could realistically result in the loss of a well.

A common precursor to a fishing expedition is lowering a lead block into the hole and taking an impression of the end of the fish to give the engineers some idea about the best fishing tool to select in order to remove the snapped drill strings or other items. The problem is, however, there is still a distinct challenge in interpreting these impressions and unless the identity is obvious, the impression can be discarded (Walker, 1984).
Inflammatory Cytokines IL-32 and IL-17 Have Common Signaling Intermediates despite Differential Dependence on TNF-Receptor 1
Authors: Turner-Brannen Emily , Choi Ka-Yee Grace , Arsenault Ryan , El-Gabalawy Hani , Napper Scott , Mookherjee Neeloffer
Published: May 2011

Cytokines IL-32 and IL-17 are emerging as critical players in the pathophysiology of immune-mediated chronic inflammatory diseases. It has been speculated that the molecular mechanisms governing IL-32– and IL-17–mediated cellular responses are differentially dependent on the TNF pathway. In this study, kinome analysis demonstrated that following stimulation with cytokine IL-32, but not IL-17, there was increased phosphorylation of a peptide target corresponding to TNF-R1. Consistent with this observation, blocking TNF-R1 resulted in a suppression of IL-32–induced downstream responses, indicating that IL-32–mediated activity may be dependent on TNF-R1. In contrast, blocking TNF-R1 did not affect IL-17–induced downstream responses. Kinome analysis also implicated p300 (transcriptional coactivator) and death-associated protein kinase-1 (DAPK-1) as signaling intermediates for both IL-32 and IL-17. Phosphorylation of p300 and DAPK-1 upon stimulation with either IL-32 or IL-17 was confirmed by immunoblots. The presence of common targets was supported by results demonstrating similar downstream responses induced in the presence of IL-32 and IL-17, such as transcriptional responses and the direct activation of NF-κB. Furthermore, knockdown of p300 and DAPK-1 altered downstream responses induced by IL-32 and IL-17, and impacted certain cellular responses induced by TNF-α and IL-1β. We hypothesize that p300 and DAPK-1 represent nodes where the inflammatory networks of IL-32 and IL-17 overlap, and that these proteins would affect both TNF-R1–dependent and –independent pathways. Therefore, p300 and DAPK-1 are viable potential therapeutic targets for chronic inflammatory diseases.
Tight Control of STAT5 Activity Determines Human CD34-Derived Interstitial Dendritic Cell and Langerhans Cell Development
Authors: van de Laar Lianne , van den Bosch Aniek , Wierenga Albertus T. J. , Janssen Harry L. A. , Coffer Paul J. , Woltman Andrea M.
Published: May 2011

Despite the crucial function of dendritic cells (DC) in immunity, the molecular mechanisms regulating human DC development remain poorly defined. STAT5 regulates various hematopoietic lineages and is activated by GM-CSF, a critical cytokine in DC development. In this study, we investigated the role of STAT5 during differentiation of human CD34+ hematopoietic progenitors into precursor DC (pre-DC) and their subsequent differentiation toward interstitial DC and Langerhans cells. Inhibiting STAT5 activity by dominant-negative STAT5 promoted Langerhans cell commitment of hematopoietic progenitors but resulted in loss of pre-interstitial DC development, showing subset-specific regulation. Increasing the low endogenous STAT5 activity by ectopic STAT5 activation downregulated expression of the critical DC transcription factor PU.1 and abrogated commitment to either DC lineage. In contrast, high STAT5 activity was beneficial in already committed pre-DC: terminal DC differentiation was associated with increased endogenous STAT5 phosphorylation levels, JAK2–STAT5 inhibition reduced terminal DC differentiation, and conditional STAT5 activation in pre-DC improved development of BDCA-1+, DC-SIGN+, and Langerin+ DC with normal maturation and T cell stimulation. These data show that STAT5 critically regulates human DC development, with specific requirements for the level of STAT5 activation at distinct differentiation stages. By regulating STAT5 activity, cytokines present at specific locations and under different pathophysiological conditions can determine the fate of DC precursors.
IL-10 Prevents Apoptosis of Brain Endothelium during Bacteremia
Authors: Londoño Diana , Carvajal Jenny , Strle Klemen , Kim Kwang S. , Cadavid Diego
Published: May 2011

IL-10–deficient mice infected with the relapsing fever bacterium Borrelia turicatae rapidly succumb to a brain hemorrhage if they are unable to clear peak bacteremia. In this study, we investigated the protective role of IL-10 during relapsing-remitting bacteremia and explored the molecular events involved in the protection of brain endothelium by IL-10. Brain endothelial injury was measured with cytotoxicity and diverse apoptotic assays, whereas the signaling pathway analysis was done by quantitative PCR array. The results showed that severe endothelial cell injury leading to hemorrhage in the brain and other organs occurred in IL-10–deficient mice during relapsing-remitting infection. Human brain microvascular endothelial cells (HBMEC) produced abundant proinflammatory mediators upon exposure to whole bacteria or purified bacterial lipoprotein but did not produce any detectable IL-10. Whole bacteria and purified outer membrane lipoprotein rapidly killed HBMEC by apoptosis in a time- and concentration-dependent manner. Exogenous IL-10 protected HBMEC from apoptosis. HBMEC apoptosis during exposure to a low number of bacteria was associated with downregulation of TNF and TNFAIP3 and upregulation of BAX. In contrast, HBMEC apoptosis during exposure to high concentrations of purified outer membrane lipoprotein was associated with marked upregulation of FAS, FAS ligand, and the adaptor molecules RIPK1 and CFLAR. Exogenous IL-10 reversed all the apoptotic signaling changes induced by whole bacteria or its purified lipoprotein. The results indicate that prominent brain endothelial cell apoptosis occurs during relapsing-remitting bacteremia in the absence of IL-10 and point to a prominent role for bacterial lipoprotein-mediated activation of FAS and caspase-3 in this process.
Tuning of Charge Densities in Graphene by Molecule Doping
Authors: Medina Henry , Lin Yung‐Chang , Obergfell Dirk , Chiu Po‐Wen
Published: May 2011

The tuning of carrier concentrations in graphene is at the heart of graphene‐based nanoelectronic and optoelectronic applications. Molecular doping, that is, taking charges from the adsorbed molecules, shows promise as a means by which to change carrier density in graphene while retaining relative high mobility. However, poor control over doping concentrations is a major obstacle to practical applications. Here, we show that lattice disorders induced by plasma exposure can be used as anchor groups. These groups serve as centers of molecule adsorption and facilitate orbital overlap between graphene and adsorbates (melamine), thus allowing for selective and tunable doping. The carrier concentration revealed by Raman shift can be progressively adjusted up to 1.4 × 1013 cm−2, depending on the coverage of melamine molecules and doping temperature. The electronic band structures of the graphene–melamine complex were calculated using density functional theory for adsorption over ideal graphene and over non‐ideal graphene with Stone–Wales (5–7‐7–5) defects. It is shown that charge transfer for adsorption on ideal graphene is negligible, while adsorption on graphene with Stone–Wales defects results in weak hole doping, which is consistent with the progressive increase of carrier density with increasing melamine coverage.
A guaranteed monotonically convergent iterative learning control
Authors: Madady Ali , Reza‐Alikhani Hamid‐Reza
Published: May 2011

This paper presents a new iterative learning control (ILC) scheme for linear discrete time systems. In this scheme, the input of the controlled system is modified by applying a semi‐sliding window algorithm, with a maximum length of n + 1, on the tracking errors obtained from the previous iteration (n is the order of the controlled system). The convergence of the presented ILC is analyzed. It is shown that, if its learning gains are chosen proportional to the denominator coefficients of the system transfer function, then its monotonic convergence condition is independent of the time duration of the iterations and depends only on the numerator coefficients of the system transfer function. The application of the presented ILC to control second‐order systems is described in detail. Numerical examples are added to illustrate the results.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Methods in Molecular Biology, Vol. 695: 3D Cell Culture: Methods and Protocols. Edited by John W. Haycock.
Authors: Chaudhuri Julian B.
Published: May 2011

Humana Press, Totowa 2010, XI+343 pp., hardcover $ 139.00.—ISBN 978‐1‐60761‐983‐3
Adsorption of Cationic Dyes from Aqueous Solution by Termite Feces, a Non‐Conventional Adsorbent
Authors: Debrassi Aline , Rodrigues Clóvis Antonio
Published: May 2011

The adsorption of three cationic dyes (rhodamine B, RB; crystal violet, CV; and malachite green, MG) onto termite feces, a low‐cost adsorbent, was investigated. The adsorbent was characterized by IR spectroscopy, point of zero charge measurement, and the Boehm titration method. The adsorption follows the pseudo‐second‐order kinetic model and the Langmuir–Freundlich isotherm with maximum adsorption capacities of 95.53 mg g−1 (RB), 75.71 mg g−1 (CV), and 44.78 mg g−1 (MG). The study of thermodynamics showed that the adsorption is a spontaneous and endothermic process. This works suggest that termite feces can be used as a new low‐cost adsorbent for cationic dye removal.
A taxonomy and survey on autonomic management of applications in grid computing environments
Authors: Rahman Mustafizur , Ranjan Rajiv , Buyya Rajkumar , Benatallah Boualem
Published: May 2011

In Grid computing environments, the availability, performance, and state of resources, applications, services, and data undergo continuous changes during the life cycle of an application. Uncertainty is a fact in Grid environments, which is triggered by multiple factors, including: (1) failures, (2) dynamism, (3) incomplete global knowledge, and (4) heterogeneity. Unfortunately, the existing Grid management methods, tools, and application composition techniques are inadequate to handle these resource, application and environment behaviors. The aforementioned characteristics impose serious requirements on the Grid programming and runtime systems if they wish to deliver efficient performance to scientific and commercial applications. To overcome the above challenges, the Grid programming and runtime systems must become autonomic or self‐managing in accordance with the high‐level behavior specified by system administrators. Autonomic systems are inspired by biological systems that deal with similar challenges of complexity, dynamism, heterogeneity, and uncertainty. To this end, we propose a comprehensive taxonomy that characterizes and classifies different software components and high‐level methods that are required for autonomic management of applications in Grids. We also survey several representative Grid computing systems that have been developed by various leading research groups in the academia and industry. The taxonomy not only highlights the similarities and differences of state‐of‐the‐art technologies utilized in autonomic application management from the perspective of Grid computing, but also identifies the areas that require further research initiatives. We believe that this taxonomy and its mapping to relevant systems would be highly useful for academic‐ and industry‐based researchers, who are engaged in the design of Autonomic Grid and more recently, Cloud computing systems. Copyright © 2011 John Wiley & Sons, Ltd.
A novel, low‐complexity, high‐speed envelope detector and its applications
Authors: Ngo Trong‐Hieu , Lee Tae‐Woo , Park Hyo‐Hoon
Published: May 2011

A compact and effective transmission envelope detector (TED), which can detect whether the absolute amplitude of an input differential signal is larger than a threshold or not, is proposed. The TED has been demonstrated to be applicable for received signal strength indicator circuit in wireless communication receivers or power management systems, and mode‐control circuit in bidirectional optical transceivers. Implemented in a 0.18 µm CMOS technology, the TED has a response time of 210 ps at 5 Gbps, occupies an active area of 0.05 mm2, and consumes 1 mA from 1.8 V supply. Copyright © 2011 John Wiley & Sons, Ltd.
MOCVD Fabrication of Magnesium Fluoride Films: Effects of Deposition Parameters on Structure and Morphology
Authors: Fragalà Maria E. , Toro Roberta G. , Privitera Salvatore , Malandrino Graziella
Published: May 2011

Magnesium fluoride (MgF2) films are fabricated via low pressure metal‐organic (MO)CVD on glass or quartz substrates from the novel single‐source precursor Mg(hfa)2 · 2H2O · 2diglyme. The nature and quality of films are scrutinized depending on relevant operational parameters, namely the deposition temperature, the precursor vaporization rate, and finally the flow of the oxygen reacting gas. Grazing incidence X‐ray diffraction (GIXRD) data point to the formation of crystalline MgF2 films. Scanning electron microscope (SEM) images indicate very homogeneous surfaces with grain dimensions dependent upon operational conditions, while energy dispersive X‐ray (EDX) analyses point to the absence of any C or O contaminants. Smooth and homogeneous surfaces can be obtained upon deposition under high oxygen flow. The MgF2 film deposited on glass at 400 °C under optimized conditions shows a ∼80% transmittance in the range 300 − 800 nm. The high crystalline and optical quality of the MgF2 films, deposited using mild deposition temperatures (< 450 °C) still confirms MOCVD as a versatile and competitive deposition technique.
Pyrrolopyrrole Cyanines: Effect of Substituents on Optical Properties
Authors: Fischer Georg M. , Klein Matthias K. , Daltrozzo Ewald , Zumbusch Andreas
Published: May 2011

To tune their optical properties, a large variety of pyrrolopyrrole cyanines (PPCys) were synthesized with substitutedheteroaromatics such as quinoline, benzothiazole, and oxazole derivatives as terminal groups. Thus, a broad range of stable, highly fluorescing near‐infrared (NIR) dyes with high absorptivities between 690 to 845 nm is accessible. The large number of newly synthesized compounds allows a detailed discussion of the correlation between molecular structure and the optical properties of the first electronic transition.
The living‐tissue microscope: the importance of studying stem cells in their natural, undisturbed microenvironment
Authors: Spradling Allan C
Published: May 2011

Advances in stem cell research highlight the importance of analysing multicellular interactions in vivo before modelling them in cell culture systems. Gain‐of‐function assays such as transplantation are useful, but are not equivalent to studying cells in their natural, undisturbed microenvironment. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Optical functionalism of azopolymers: Photoinduced orientation and re‐orientation of dendrimer structures of different generations
Authors: Navickaitė Gabrielė , Seniutinas Gediminas , Tomašiūnas Roland , Petruškevičius Raimondas , Kampars Valdis
Published: May 2011

We report on second order optical nonlinearity in E–O active polymer materials – dendrimer structures of three different generations – investigated by means of all‐optical poling. Chromophores containing azo junction used for experiments were prepared as guest‐host type system based on polycarbonate matrix spin‐coated on a glass substrate. Molecular orientation and subsequent decay kinetics in two modes of reading beam performance, when reading (i) not permanent irradiated or (ii) permanent irradiated, were measured. Depending on the intensity of reading beam the decay for different structures was measured and analyzed. Experimental results show that read‐out intensity determines faster decay of second harmonic signal, i.e., effective “washing‐out” the polar orientation alignment of molecules.
Temporal-logic property preservation under Z refinement
Authors: Derrick John , Smith Graeme
Published: May 2011

Formal specification languages such as Z, B and VDM are used in the incremental development of abstract specifications (suitable for establishing required properties) to more concrete specifications (resembling the final implementation). This incremental development process, known as
refinement
, preserves all observable properties of the original abstract specification. Recent research has looked at applying temporal-logic model checking to such specification languages. While this assists in the establishment of properties of the abstract specification, temporal-logic properties typically refer to state variables which are regarded as non-observable. Hence, such properties are not guaranteed to be preserved by refinement. This paper investigates the classes of temporal-logic properties which are preserved by refinement, and for some of those properties that are not preserved in general, the restrictions on the refinement process under which they are preserved. Results are presented for the temporal logics LTL, CTL and the 
μ
-calculus and the formal specification language Z. They apply equally, however, to related formal specification languages such as B and VDM.
Dietary Guar Gum Reduces Lymph Flow and Diminishes Lipid Transport in Thoracic Duct‐Cannulated Rats
Authors: Shirouchi Bungo , Kawamura Sayaka , Matsuoka Ryosuke , Baba Sanae , Nagata Kazuko , Shiratake Sawako , Tomoyori Hiroko , Imaizumi Katsumi , Sato Masao
Published: May 2011

Guar gum has a well‐recognized hypolipidemic effect. This effect is thought to be due to the physicochemical properties of guar gum, which may cause changes in adsorption of lipids or the viscosity of the intestinal contents. Guar gum is a non‐specific absorption inhibitor of any type of lipid‐soluble compound. Permanent lymph duct cannulation was performed on rats to investigate the effects of dietary guar gum on lymph flow and lipid transport. Rats fed a 5% guar gum diet were compared with those fed a 5% cellulose diet, and lymph was collected after feeding. The water‐holding capacity (WHC), settling volume in water (SV), and viscosity of guar gum were compared with those of cellulose. Rats fed with the guar gum diet had significantly lower lymph flow and lymphatic lipid transport than did rats fed with the cellulose diet. The WHC, SV, and viscosity of guar gum were significantly higher than those of cellulose. We propose that dietary guar gum reduces lymph flow and thereby diminishes lipid transport by means of its physicochemical properties related to water behavior in the intestine.
Service-oriented middleware for the Future Internet: state of the art and research directions
Authors: Issarny Valérie , Georgantas Nikolaos , Hachem Sara , Zarras Apostolos , Vassiliadist Panos , Autili Marco , Gerosa Marco Aurélio , Hamida Amira Ben
Published: May 2011

Service-oriented computing is now acknowledged as a central paradigm for Internet computing, supported by tremendous research and technology development over the last 10 years. However, the evolution of the Internet, and in particular, the latest Future Internet vision, challenges the paradigm. Indeed, service-oriented computing has to face the ultra large scale and heterogeneity of the Future Internet, which are orders of magnitude higher than those of today’s service-oriented systems. This article aims at contributing to this objective by identifying the key research directions to be followed in light of the latest state of the art. This article more specifically focuses on research challenges for service-oriented middleware design, therefore, investigating service description, discovery, access, and composition in the Future Internet of services.
The impact of pain in patients with polyneuropathy
Authors: Poliakov Ilia , Toth Cory
Published: May 2011

Peripheral neuropathy (PN) is a common impairment which may impact upon quality of life (QoL). Neuropathic pain (NeP) occurs in up to 50% of patients with PN. We hypothesized that disability and impaired quality of life resulting from PN is primarily associated with presence of NeP. Our aim was to determine using prospectively identified PN patients presenting to a tertiary care neuromuscular clinic if presence of NeP (PN + NeP) had greater impact upon QoL than with absence of NeP (PN−NeP). A second aim was to identify if QoL varied based upon etiology of PN. We analyzed neuropathy severity (Toronto Clinical Neuropathy Score (TCSS)), pain quantity and quality (Visual Analogue Scale (VAS) pain score, Brief Pain Inventory (BPI)), QoL and health status measures (EuroQol Instrument 5 Domains (EQ‐5D), Medical Outcomes Sleep Study Scale (MOSSS), Hospital Anxiety and Depression Scale (HADS), Short Form 36 Health Survey (SF‐36)) and Health Assessment Questionnaire (HAQ) to determine impact of NeP. Although both cohorts were epidemiologically similar and had similar severity of PN, PN + NeP patients had considerably greater impairment for QoL, sleep efficacy, and features of anxiety and depression, leading to substantially greater health care resources utilization when compared to PN−NeP patients. The magnitude of NeP severity was the only explaining variable for increased impact upon QoL measures and diminishing overall wellbeing. Our results confirm that NeP is a primary indicator for worsening QoL and diminished overall wellbeing in PN patients. The etiology of PN did not influence levels of NeP‐related compromise of QoL. Further studies are needed to determine optimal methods for management of PN + NeP patients subjected to a significant physiological, psychological and functional burden.
Norm index formula for the Tate kernels and applications
Authors: Assim J. , Movahhedi A.
Published: May 2011

Let p be an odd prime and L/F a p-extension of number fields with Galois group G. The aim of this paper is to provide answers to a question of Kahn concerning lower bounds for the order of the kernel and cokernel of the functorial map K2F → K2LG. To this end, we first determine a norm index formula for generalized Tate kernels and then express our lower bounds in terms of the ramification in L/F.
The fundamental theorem via derived Morita invariance, localization, and 1-homotopy invariance
Authors: Tabuada Gonçalo
Published: May 2011

We prove that every functor defined on dg categories, which is derived Morita invariant, localizing, and 1-homotopy invariant, satisfies the fundamental theorem. As an application, we recover in a unified and conceptual way, Weibel and Kassel's fundamental theorems in homotopy algebraic K-theory, and periodic cyclic homology, respectively.
Breakdown of the shallow water equations due to growth of the horizontal vorticity
Authors: BRIDGES THOMAS J. , NEEDHAM DAVID J.
Published: May 2011

In an oceanographic setting, the shallow water equations are an asymptotic approximation to the full Euler equations, in the limit ϵ =h0/L→ 0, withh0being the vertical length scale andLa horizontal length scale associated with the fluid layer. However, in arriving at the shallow water equations an additional key step in the derivation is the condition that at some reference time (e.g.t= 0) the thin-layer horizontal vorticity field is identically zero, which corresponds to the horizontal fluid velocity field being independent of the vertical coordinate,z, att= 0. With this condition in place, the ‘thin-layer equations’ reduce exactly to the shallow water equations. In this paper, we show that this exact condition may be unstable: small, even infinitesimal, perturbations of the thin-layer horizontal vorticity field can grow without bound. When the thin-layer horizontal vorticity grows to be of order 1, the shallow water equations are no longer asymptotically valid as a model for shallow water hydrodynamics, and the ‘thin-layer equations’ must be adopted in their place.
Nasal myiasis by Oestrus ovis second stage larva in an immunocompetent man: case report and literature review
Authors: Einer H , Ellegård E
Published: May 2011

Objective:

We report a case of an Oestrus ovis larva which developed into the second larval stage within a healthy, immunocompetent human, and we review the relevant literature.

Methods:

Clinical case report and Pubmed search of reports of human nasal myiasis due to Oestrus ovis, especially those describing the larval stage.

Results:

Humans are not normally hosts of the sheep nasal bot fly, but infestations by its larvae have been described. The eye is the most common site, but larvae have occasionally been found in the human nose. Transformation of larvae into the second and third stages, within the human nose, is even more uncommon.

Conclusion:

To the best of our knowledge, we report the first Swedish case, and the third case world-wide, of Oestrus ovis larval development beyond the first larval stage, within an immunocompetent, healthy human.
Veno-venous bridges: the forerunners of the sinus venosus defect
Authors: Butts Ryan J. , Crean Andrew M. , Hlavacek Anthony M. , Spicer Diane E. , Cook Andrew C. , Oechslin Erwin N. , Anderson Robert H.
Published: May 2011

Background

Differentiation of the so-called sinus venosus defect from other defects permitting shunting between the atrial chambers remains problematic. The lesion is not a true septal defect, and current theories to explain the existence of the sinus venosus defect fall short. The presence of persistent systemic to pulmonary venous connections has been proposed to explain the existence of the sinus venosus defect.

Methods

Clinical histories and radiological findings of six patients are reviewed. Three patients have veno-venous bridges, two have partial anomalous pulmonary venous connections, and one patient has a sinus venosus defect. The clinical information is reviewed, along with current developmental and morphological considerations.

Discussion

We provide radiographic, developmental, and morphological evidence to support the theory that a so-called sinus venosus defect is the consequence of persistence of foetal systemic to pulmonary veno-venous bridges, rather than of deficiencies in atrial septation.
Photodissociation investigation of doubly charged ethanol clusters induced by inner-shell electron ionization
Authors: Tamenori Y. , Okada K. , Tabayashi K. , Hiraya A. , Gejo T. , Honma K.
Published: May 2011

Fragmentation of doubly charged ethanol clusters [(C2H5OH)n] following the O 1s ionization has been investigated by means of the photoelectron-photoion-photoion coincidence (PEPIPICO) method. The dominant fission channel of (C2H5OH)n2+ was the formation of protonated cluster ion pairs [H(C2H5OH)l+/H(C2H5OH)m+]. The fragmentation mechanisms of these ion pairs were discussed based on the analysis of the PEPIPICO contour shape. It was clarified that the prominent fragmentation channel was a secondary decay mechanism, where neutral evaporation occurs after charge separation. On the other hand, the formation of small fragment ions was suppressed, excluding the formation of certain specific fragments (H3O+, C2H5+/COH+, and C2H4OH+). The formation of small fragment ions was suppressed due to the cooling effect caused by the neutral evaporation and the decrease in the electrostatic repulsive force caused by charge separation.
Mixed quantum classical simulations of excitons in peptide helices
Authors: Goj Anne , Bittner Eric R.
Published: May 2011

We use mixed classical/quantum simulations to study the time dependence of an excitation of a C=O vibration on a 3–10 helix of α-aminoisobutyric acid, a system which represents a test case for the formation of self-trapped vibrational excitation states on protein helices. Due to the inherent disorder in the system caused by the finite temperature and fluctuations in hydrogen bonding, the excitation tunnels randomly among C=O sites along the helix. Quantum forces are insufficient to establish a coherent relationship between the location of the excitation and the contraction of hydrogen bonds around this site. Our simulations indicate that the excitation frequently becomes localized on the end of the helix due to the defect in helical structure caused by unwinding. Our results generally do not support the existence of Davydov type solitons in biological helix systems under physiological conditions.
Quasielastic neutron scattering study of hydrogen motions in an aqueous poly(vinyl methyl ether) solution
Authors: Capponi S. , Arbe A. , Cerveny S. , Busselez R. , Frick B. , Embs J. P. , Colmenero J.
Published: May 2011

We present a quasielastic neutron scattering (QENS) investigation of the component dynamics in an aqueous Poly(vinyl methyl ether) (PVME) solution (30% water content in weight). In the glassy state, an important shift in the Boson peak of PVME is found upon hydration. At higher temperatures, the diffusive-like motions of the components take place with very different characteristic times, revealing a strong dynamic asymmetry that increases with decreasing T. For both components, we observe stretching of the scattering functions with respect to those in the bulk and non-Gaussian behavior in the whole momentum transfer range investigated. To explain these observations we invoke a distribution of mobilities for both components, probably originated from structural heterogeneities. The diffusive-like motion of PVME in solution takes place faster and apparently in a more continuous way than in bulk. We find that the T-dependence of the characteristic relaxation time of water changes at T ≲ 225 K, near the temperature where a crossover from a low temperature Arrhenius to a high temperature cooperative behavior has been observed by broadband dielectric spectroscopy (BDS) [S. Cerveny, J. Colmenero and A. Alegría, Macromolecules, 38, 7056 (2005)10.1021/ma050811t]. This observation might be a signature of the onset of confined dynamics of water due to the freezing of the PVME dynamics, that has been selectively followed by these QENS experiments. On the other hand, revisiting the BDS results on this system we could identify an additional “fast” process that can be attributed to water motions coupled with PVME local relaxations that could strongly affect the QENS results. Both kinds of interpretations, confinement effects due to the increasing dynamic asymmetry and influence of localized motions, could provide alternative scenarios to the invoked “strong-to-fragile” transition.
The grain size and temperature dependence of the thermal conductivity of polycrystalline, tetragonal yttria-stabilized zirconia
Authors: Limarga Andi M. , Clarke David R.
Published: May 2011

The thermal conductivity of optically transparent, yttria-stabilized tetragonal zirconia having a range of grain sizes from 100 to 180 nm has been measured from just below its approximate Debye temperature up to 1000 °C. It is found that the grain size dependence is most marked at room temperature, decreasing with increasing temperature until being indistinguishable at the highest temperatures. The Kapitza thermal resistance of the grain boundaries is found to be almost independent of temperature, with a value of Rk=4.5±0.5×10−9 m2K/W and an estimated grain boundary phonon transparency of ∼0.9.
Structural heterogeneity and pressure-relaxation in compressed borosilicate glasses by in situ small angle X-ray scattering
Authors: Reibstein S. , Wondraczek L. , de Ligny D. , Krolikowski Sebastian , Sirotkin S. , Simon J.-P. , Martinez V. , Champagnon B.
Published: May 2011

We report on Brillouin and in situ small angle X-ray scattering (SAXS) analyses of topological heterogeneity in compressed sodium borosilicate glasses. SAXS intensity extrapolated to very low angular regimes, I(q = 0), is related to compressibility. From Brillouin scattering and analyses of the elastic properties of the glass, the Landau-Placzek ratio is determined and taken as a direct reflection of the amplitude of frozen-in density fluctuations. It is demonstrated that with increasing fictive pressure, topological (mid- and long-range) homogeneity of the glass increases significantly. Heating and cooling as well as isothermal scans were performed to follow the evolution of density fluctuations upon pressure recovery. For a sample with a fictive pressure pf of 470 MPa, complete recovery to pf = 0.1 MPa was observed to occur close to the glass transition temperature. The values of fictive and apparent fictive temperature, respectively, as obtained via the intersection method from plots of I(q = 0) vs. temperature were found in good agreement with previous calorimetric analyses. Isothermal scans suggest that mid- and long-range recovery govern macroscopic density relaxation.
Ultralow-voltage design of graphene PN junction quantum reflective switch transistor
Authors: Sohier Thibault , Yu Bin
Published: May 2011

We propose the concept of a graphene-based quantum reflective switch (QRS) for low-power logic application. With the unique electronic properties of graphene, a tilted PN junction is used to implement logic switch function with 103 ON/OFF ratio. Carriers are reflected on an electrostatically induced potential step with strong incidence-angle-dependency due to the widening of classically forbidden energies. Optimized design of the device for ultralow-voltage operating has been conducted. The device is constantly ON with a turning-off gate voltage around 180 mV using thin HfO2 as the gate dielectric. The results suggest a class of logic switch devices operating with micropower dissipation.
Epitaxially grown semiconducting hexagonal boron nitride as a deep ultraviolet photonic material
Authors: Dahal R. , Li J. , Majety S. , Pantha B. N. , Cao X. K. , Lin J. Y. , Jiang H. X.
Published: May 2011

Hexagonal boron nitride (hBN) has emerged as an important material for various device applications and as a template for graphene electronics. Low-dimensional hBN is expected to possess rich physical properties, similar to graphene. The synthesis of wafer-scale semiconducting hBN epitaxial layers with high crystalline quality and electrical conductivity control has not been achieved but is highly desirable. Large area hBN epitaxial layers (up to 2 in. in diameter) were synthesized by metal organic chemical vapor deposition. P-type conductivity control was attained by in situ Mg doping. Compared to Mg-doped wurtzite AlN, which possesses a comparable energy band gap (∼6 eV), dramatic reductions in Mg acceptor energy level and P-type resistivity (by about six to seven orders of magnitude) have been realized in hBN epilayers. The ability of conductivity control and wafer-scale production of hBN opens up tremendous opportunities for emerging applications, ranging from revolutionizing p-layer approach in III-nitride deep ultraviolet optoelectronics to graphene electronics.
High-temperature transport properties of Ca0.98RE0.02MnO3−δ (RE=Sm, Gd, and Dy)
Authors: Liu Chia-Jyi , Bhaskar Ankam , Yuan J. J.
Published: May 2011

We report measurements of electrical resistivity and thermopower on CaMnO3−δ and Ca0.98RE0.02MnO3−δ (RE=Sm, Gd, and Dy) prepared by solid state reaction. CaMnO3−δ exhibits nonmetal-like temperature dependence of resistivity while metal-like temperature dependence of thermopower. This inconsistency can be explained by the extrinsic carriers arising from oxygen defects using two-band model. Ca0.98RE0.02MnO3−δ exhibits metal-like temperature dependence in both resistivity and thermopower. The transition to metal-like behavior resembles the case in degenerate semiconductors and can be attributed to an impurity band formation with characteristic of hybridized Mn 3d eg and O 2p states due to electron doping via partial substitution of lanthanides for Ca2+ and oxygen defects.
Towards weakening of the Coulomb blockade in artificially prepared clusters of superconducting grains
Authors: Sergeenkov Sergei
Published: May 2011

The relative role of dipole-dipole interactions between induced polarization moments in the total charge balance of a model system of two clusters (each cluster contains N superconducting grains) is analyzed. It is found that, due to its orientational nature, the dipole energy between clusters may overcome the direct Coulomb coupling between grains (within a single cluster). To verify the model predictions experimentally, specially prepared clusters with markedly distinctive grain-grain (εc) and cluster-cluster (εd) dielectric properties are needed. More specifically, clusters of Al-based superconducting grains embedded into SrTiO3 dielectric matrix (with εc ≃ 104) and separated by a dielectric layer of Al2O3 (with εd ≃ 10) would result in a noticeable decrease of the total charging energy of the system.
High-resolution hard-x-ray microscopy using second-order zone-plate diffraction
Authors: Yi Jaemock , Chu Yong S , Chen Yu-Tung , Chen Tsung-Yu , Hwu Y , Margaritondo G
Published: May 2011

Odd-order diffraction of zone plates (ZPs) is already used for x-ray microscopy but the potential offered by even-order diffraction must still be fully exploited. Width differences between lines and interline spaces transfer intensity from odd-order to even-order diffractions. Here we show that the resulting intense second-order diffraction provides a reasonable tradeoff between spatial resolution and intensity—and constitutes a viable strategy for x-ray microscopy to reach sub-20 nm resolution, in spite of the imperfections of high-aspect-ratio ZPs and of other difficulties.
Achieving high mobility ZnO : Al at very high growth rates by dc filtered cathodic arc deposition
Authors: Mendelsberg R J , Lim S H N , Zhu Y K , Wallig J , Milliron D J , Anders A
Published: May 2011

Achieving a high growth rate is paramount for making large-area transparent conducting oxide coatings at a low cost. Unfortunately, the quality of thin films grown by most techniques degrades as the growth rate increases. Filtered dc cathodic arc is a lesser known technique which produces a stream of highly ionized plasma, in stark contrast to the neutral atoms produced by standard sputter sources. Ions bring a large amount of potential energy to the growing surface which is in the form of heat, not momentum. By minimizing the distance from cathode to substrate, the high ion flux gives a very high effective growth temperature near the film surface without causing damage from bombardment. The high surface temperature is a direct consequence of the high growth rate and allows for high-quality crystal growth. Using this technique, 500–1300 nm thick and highly transparent ZnO : Al films were grown on glass at rates exceeding 250 nm min−1 while maintaining resistivity below 5 × 10−4 Ω cm with electron mobility as high as 60 cm2 V−1 s−1.
Line plus arc source trajectories and their R-line coverage for long-object cone-beam imaging with a C-arm system
Authors: Yu Zhicong , Wunderlich Adam , Dennerlein Frank , Lauritsch Günter , Noo Frédéric
Published: May 2011

Cone-beam imaging with C-arm systems has become a valuable tool in interventional radiology. Currently, a simple circular trajectory is used, but future applications should use more sophisticated source trajectories, not only to avoid cone-beam artifacts but also to allow extended volume imaging. One attractive strategy to achieve these two goals is to use a source trajectory that consists of two parallel circular arcs connected by a line segment, possibly with repetition. In this work, we address the question of R-line coverage for such a trajectory. More specifically, we examine to what extent R-lines for such a trajectory cover a central cylindrical region of interest (ROI). An R-line is a line segment connecting any two points on the source trajectory. Knowledge of R-line coverage is crucial because a general theory for theoretically exact and stable image reconstruction from axially truncated data is only known for the points in the scanned object that lie on R-lines. Our analysis starts by examining the R-line coverage for the elemental trajectories consisting of (i) two parallel circular arcs and (ii) a circular arc connected orthogonally to a line segment. Next, we utilize our understanding of the R-lines for the aforementioned elemental trajectories to determine the R-line coverage for the trajectory consisting of two parallel circular arcs connected by a tightly fit line segment. For this trajectory, we find that the R-line coverage is insufficient to completely cover any central ROI. Because extension of the line segment beyond the circular arcs helps to increase the R-line coverage, we subsequently propose a trajectory composed of two parallel circular arcs connected by an extended line. We show that the R-lines for this trajectory can fully cover a central ROI if the line extension is long enough. Our presentation includes a formula for the minimum line extension needed to achieve full R-line coverage of an ROI with a specified size, and also includes a preliminary study on the required detector size, showing that the R-lines added by the line extension are not constraining.
The pharmacology of the drugs used in acute pain
Authors: Bromley Lesley
Published: May 2011

Drug treatment is the mainstay of acute pain management.

An understanding of the pharmacology of the drugs used is essential for rational acute pain management.

Drugs that have a primary analgesic action have been used traditionally.

Recently, adjunct drugs and combinations have been shown to be more effective than analgesics alone.

In the past 20 years, the route of administration and the timing of analgesic drugs have played a greater part in efficient acute pain management.
Acute pain in the elderly
Authors: Wagg Adrian , Gadgil Shashi
Published: May 2011

Physiological changes that occur with age affect the pharmacokinetics and pharmacodynamics of drugs used in acute pain management.

Elderly patients are often reluctant to complain of pain and seek treatment and may sometimes be unable to express pain due to impaired cognition or language.

Evidence suggests the elderly as a group that receive inadequate analgesia and are often in pain.

Health care professionals are often reluctant to administer sufficient analgesia due to fear of encouraging addiction or inducing side effects.

The approach to pain management in this group should follow the World Health Organization (WHO) analgesic ladder with close monitoring for potential side effects and with escalation of treatment till sufficient analgesia is achieved.

Choice of drugs and the route of administration should be tailored to the individual patient and should consider the nature of their pain and any disability or co-morbidity that will affect their response to the chosen agent.

Non-steroidal anti-inflammatory drugs (NSAIDs) should be used with extreme caution, monitoring for potential gastrointestinal (GI) and renal side effects and long-term use should be avoided if possible.

Opioids are effective analgesics and should not be denied to the elderly but their use should be monitored carefully and side effects such as nausea and constipation anticipated and treated.
Acute pain in the neurological patient
Authors: Chong Sam , Ganesalingham J.
Published: May 2011

Acute pain is a common presenting symptom in patients with neurological conditions.

Acute onset headache may indicate a life-threatening underlying condition.

Lumbosacral and cervical spine pain are commonly caused by degenerative disease but there are sometimes clues to indicate alternative pathologies.

Acute pain arising from the peripheral nervous system and muscles are usually inflammatory in origin.

A careful history and examination is crucial to assess patients with neurological pain.

Opioids may be used in combination of an anti-epileptic or antidepressant drug in the treatment of acute neuropathic pain.