bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduction of thermal conductivity in semiconducting composite films consisting of silicon and transition-metal silicide nanocrystals
Authors: Uchida N. , Ohishi Y. , Kurosaki K. , Yamanaka S. , Tada T. , Kanayama T. 
Published: April 2013

ABSTRACTWe observed significant reduction of thermal conductivity in semiconducting composite films of Si and molybdenum (Mo)-silicide nanocrystals (NCs). These films were synthesized by phase separation due to annealing at 700 -1000°C from sputtered amorphous Mo–Si alloy. Transmission electron microscope images showed that the NCs were grown to diameters of∼10 nm in the films by annealing at 800°C. Raman scattering spectra showed lower shift of peak positions of Si transverse optical (TO) phonon due to the confinement effect and the tensile stress. The electrical resistivity of the films was 0.17- 9 Ωm at room temperature and showed a semiconducting temperature dependence at 20-400 K. Thermal conductivity of the film was reduced to 4.4 W/mK by enhancement of phonon scattering at NC interfaces, suggesting that the composite film is promising as a high-efficiency Si-based thermoelectric material.
A New Thermogeomechanical Theory for Gravity Drainage in Steam-Assisted Gravity Drainage
Authors: Cokar M.. , Kallos M.S.. S. , Gates I.D.. D. 
Published: April 2013

Summary
Oil-sands reservoirs in western Canada hold more than 170 billion bbl of recoverable heavy oil and bitumen representing a significant source of unconventional oil. At in-situ conditions, the majority of this oil has essentially no initial mobility because of its high viscosity, which is typically in the hundreds of thousands to millions of centipoises. In steam-assisted gravity drainage (SAGD), steam injected into the formation heats oil at the edge of a depletion chamber, thus raising the mobility, ko/μo, of bitumen. Three main effects account for the increase of oil mobility. First, bitumen at steam temperature has viscosity typically less than 20 cp. Second, it is believed that shear, which is caused by thermal-expansion gradients, dilates the oil sand and causes enhanced permeability. Third, dilation at the chamber edge leads to smaller residual oil saturation (ROS). Because the production rate of SAGD is directly tied to the drainage rate of mobilized oil at the chamber edge, the thermogeomechanics of the oil sand at the chamber edge is a control on the performance of SAGD. In this study, a novel SAGD formula is derived that accounts for thermogeomechanical effects at the edge of the chamber. This paper couples dilation effects arising from thermal expansion into an analytical model for SAGD oil rate. The results reveal that volumetric expansion at the edge of the chamber plays a significant role in enabling effective drainage of bitumen to the production well.
Clinical Performance of Ormocer, Nanofilled, and Nanoceramic Resin Composites in Class I and Class II Restorations: A Three-year Evaluation
Authors: Mahmoud SH , El-Embaby AE , AbdAllah AM 
Published: April 2013

SUMMARY

Purpose
This prospective long-term clinical trial evaluated and compared the three-year clinical performance of an ormocer, a nanofilled, and a nanoceramic resin composite with that of a microhybrid composite placed in Class I and Class II cavities.

Methods
Forty patients, each with four Class I and II restorations under occlusion, were enrolled in this study. A total of 160 restorations were placed, 25% for each material, as follows: an ormocer-based composite, Admira; a nanofilled resin composite, Filtek Supreme XT; a nanoceramic resin composite, Ceram X; and a microhybrid resin composite, Tetric Ceram. A single operator placed all restorations according to the manufacturers' instructions. Immediately after placement the restorations were finished/polished. Clinical evaluation was performed at baseline and at yearly intervals after placement by two other independent examiners using modified US Public Health Service (USPHS) criteria. The changes in the USPHS parameters during the three-year period were analyzed with the Friedman test. Comparison of the baseline scores with those at the recall visits was made using the Wilcoxon signed rank test. The level of significance was set at p &lt; 0.05.

Results
All materials showed only minor changes, and no differences were detected between their performance at baseline and after three years. Only two ormocer, one nanofilled, and one microhybrid restorations in molars failed because of loss of retention. Regarding the clinical performance, there were no statistically significant differences among the materials used (p&gt;0.05).

Conclusions
The ormocer, nanofilled, and nanoceramic composites provided acceptable clinical performance over a three-year period.
Small-scale horizontal variability of snow, sea-ice thickness and freeboard in the first-year ice region north of Svalbard
Authors: Haapala Jari , Lensu Mikko , Dumont Marie , Renner Angelika H.H. , Granskog Mats A. , Gerland Sebastian 
Published: April 2013

AbstractVariability of sea-ice and snow conditions on the scale of a few hundred meters is examined using in situ measurements collected in first-year pack ice in the European Arctic north of Svalbard. Snow thickness and surface elevation measurements were performed in the standard manner using a snow stick and a rotating laser. Altogether, 4109 m of measurement lines were surveyed. The snow loading was large, and in many locations the ice freeboard was negative (38.8% of snowline measurements), although the modal ice and snow thickness was 1.8 m. The mean of all the snow thickness measurements was 36 cm, with a standard deviation of 26 cm. The mean freeboard was only 3 cm, with a standard deviation of 23 cm. There were noticeable differences in snow thickness among the measurement sites. Over the undeformed ice areas, the mean snow thickness and freeboard were 23 and 2.4 cm, respectively. Over the ridged ice areas, the mean freeboard was only –0.3 cm due to snow accumulation on the sails of ridges (average thickness 54 cm). These findings imply that retrieval algorithms for converting freeboard to ice thickness should take account of spatial variability of snow cover.
Resolution of ice streams and outlet glaciers in large-scale simulations of the Greenland ice sheet
Authors: Greve Ralf , Herzfeld Ute C. 
Published: April 2013

AbstractThe dynamic/thermodynamic shallow-ice model SICOPOLIS is applied to the Greenland ice sheet. Paleoclimatic spin-ups from 125 ka BP until today, as well as future-climate experiments 500 years into the future, are carried out with three different grid spacings, namely 20, 10 and 5 km. The scenarios are a subset of those specified by the SeaRISE (Sea-level Response to Ice Sheet Evolution) community effort. The bed topography includes improved troughs for Jakobshavn Isbræ, Helheim, Kangerdlugssuaq and Petermann glaciers, processed by an algorithm that preserves shape, orientation and continuity of the troughs on the 5 km scale. Comparison of simulated and observed present-day surface velocities shows that these ice streams and outlet glaciers are resolved with different accuracies, ranging from poor (20 km grid) to reasonably good (5 km grid). In the future-climate experiments, the simulated absolute ice volumes depend significantly on the resolution, while the sensitivities (ice volumes relative to the constant-climate control run) vary only by a few centimeters of sea-level equivalent.
Intra-articular injections of autologous platelet concentrates in dogs with surgical reparation of cranial cruciate ligament rupture
Authors: Carmona J. U. , Rezende C. M. F. , Silva R. F. 
Published: April 2013

SummaryObjective The objective of this study was to evaluate by clinical, radiographic, and force plate gait analyses the effect of postsurgical intra-articular injections of autologous platelet concentrates (PC) in a small group of dogs with cranial cruciate ligament (CCL) rupture.Methods The ten dogs used in this study were initially presented with CCL rupture and underwent ligament replacement surgery by fascia lata autograft guided by arthroscopy. Six dogs received three intra-articular injections of PC (PC group); one dose was injected immediately after surgery, and two additional doses were injected at two-week intervals. The remaining four dogs received only nutraceuticals (control group). All dogs were evaluated by clinical examination, serial radiography, and force plate gait analyses at monthly intervals up to 90 days.Results The clinical follow-up of the PC-treated group indicated a better outcome than the control group. Radiographic evaluation was not conclusive. Values of peak vertical reaction force and vertical impulse of the affected limbs were only significantly larger on the 90th postoperative day in the PC group compared to the control group.Clinical significance Our results indicate that autologous PC might improve functional outcome after intra-articular cranial cruciate ligament repair. The effect of PC when using other repair procedures warrants additional studies.
Medullary decompression of the radius as treatment for lameness in a horse
Authors: Carstens A. , Rubio-Marténez L. M. 
Published: April 2013

SummaryIncreased intraosseous pressure (IOP) is a well-characterized source of pain in humans that can be successfully treated by medullary decompression. This report describes the clinical and diagnostic findings, treatment and successful outcome of a horse with a four week long, non-weight bearing lameness secondary to suspected traumaticallyinduced increased IOP in the left radius. Scintigraphic examination characterized by severe increase in radiopharmaceutical uptake within the affected radius aided in the initial localization of the source of lameness. Decompression of the affected radius was performed by drilling two 3.2 mm tracts through the lateral bone cortex into the medullary cavity. Intramedullary pressure in the radius was measured (37-39 mmHg). Dramatic clinical improvement was observed after surgical decompression of the affected bone and the horse showed full recovery and returned to previous exercise use by 12 months after treatment. Gradual decrease in radial radiopharmaceutical uptake was observed during the following year. Increased IOP should be considered as a cause of lameness in horses and scintigraphic examination may aid in its diagnosis. Medullary decompression may be a successful treatment in some cases.
Le financement de la vie politique française par les entreprises 1970-2012
Authors: Phélippeau Éric 
Published: April 2013

L’objectif de cet article est de revenir sur les mobilisations associées aux nouvelles règles qui ont prétendu encadrer le financement de la vie politique française, et plus spécialement certaines ressources d’origine privée : les dons des entreprises. Entre la fin des années 1980 et le milieu des années 1990, ces financements, d’abord occultes, furent soudain légalisés avant d’être de nouveau prohibés. L’analyse de ce processus livre un nouvel éclairage de ces brusques revirements. Elle montre combien la collecte et la gestion de telles ressources reflètent de sérieuses inégalités entre candidats. L’étude des débats parlementaires réformant cet enjeu lié au financement politique nous permet de pénétrer le sens pratique des députés impliqués dans ces réformes politiques. Finalement, l’examen du contexte de la prohibition des dons d’entreprises nous aide à comprendre comment les règles en matière de divulgation jouèrent un rôle important dans ce changement de cap. Par la suite, la mise en œuvre de ces nouvelles règles fut à l’origine d’incertitudes (progressivement tranchées par les juridictions), faisant naître dans le même temps d’autres manières de contourner les lois. Au final, toute l’enquête constitue plus généralement une occasion de poser la question du tracé fluctuant de la frontière symbolique entre sphère politique et milieux d’affaires ou cercles socio-économiques.
Supramolecular Engineering of Perylene Bisimide Assemblies Based on Complementary Multiple Hydrogen Bonding Interactions
Authors: Seki Tomohiro , Lin Xu , Yagai Shiki 
Published: April 2013

AbstractPerylene bisimide (PBI) dyes are among the most extensively studied functional π‐building blocks and have outstanding optical and electronic properties. Most PBI assemblies that have been reported so far are based on one‐dimensional stacks formed mainly by directional π–π interactions between quadrupolar π‐systems of PBIs. More complex and elaborate supramolecular assemblies of PBIs can be constructed by using highly directional and specific intermolecular glues, such as complementary multiple hydrogen bonding interactions, and the resulting assemblies are expected to show unique functional properties. In this Focus Review, we will discuss highly‐organized assemblies of PBI dyes, the self‐assembled architectures of which are rationally controlled by directional, complementary multiple hydrogen‐bonding interactions. An overview of the construction principles of such systems is included, but special attention is focused on the significant progress achieved after the seminal review about supramolecular architectures of PBI dyes by Würthner in 2004.
Tribological properties of PBO fabric composites modified by poly (vinyl alcohol)
Authors: Guo Fang , Zhang Zhaozhu , Xu Xianghui , Jiang Wei , Wang Kun 
Published: April 2013

ABSTRACTFriction and wear behaviors of poly (vinyl alcohol) (PVA) modified PBO fabric composites were evaluated in a pin‐on‐disc friction and wear tester, and the relationship between the properties and the structure change resulting from PVA modification were intensively investigated using thermogravimetric analysis (TG) and scanning electronic microscope (SEM) equipped with an energy dispersive spectrometer (EDS). The results indicated that the PVA thin film formed on the fabric surface by chemical crosslinking reaction could improve the antiwear property of the PBO fabric composites efficiently. In argon‐300°C condition, the antiwear property of the PBO fabric composites was improved by 35%, which was due to the improvement of the bonding strength between the fabric and resin and the dispersion of the shear stress induced by the shear creep and plastic deformation of the PVA film in friction. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1313‐1320, 2013
SMET: Systematic multiple enzyme targeting – a method to rationally design optimal strains for target chemical overproduction
Authors: Flowers David , Thompson R. Adam , Birdwell Douglas , Wang Tsewei , Trinh Cong T. 
Published: April 2013

AbstractIdentifying multiple enzyme targets for metabolic engineering is very critical for redirecting cellular metabolism to achieve desirable phenotypes, e.g., overproduction of a target chemical. The challenge is to determine which enzymes and how much of these enzymes should be manipulated by adding, deleting, under‐, and/or over‐expressing associated genes. In this study, we report the development of a systematic multiple enzyme targeting method (SMET), to rationally design optimal strains for target chemical overproduction. The SMET method combines both elementary mode analysis and ensemble metabolic modeling to derive SMET metrics including l‐values and c‐values that can identify rate‐limiting reaction steps and suggest which enzymes and how much of these enzymes to manipulate to enhance product yields, titers, and productivities. We illustrated, tested, and validated the SMET method by analyzing two networks, a simple network for concept demonstration and an Escherichia coli metabolic network for aromatic amino acid overproduction. The SMET method could systematically predict simultaneous multiple enzyme targets and their optimized expression levels, consistent with experimental data from the literature, without performing an iterative sequence of single‐enzyme perturbation. The SMET method was much more efficient and effective than single‐enzyme perturbation in terms of computation time and finding improved solutions.
Translocation of cell penetrating peptides on Chlamydomonas reinhardtii
Authors: Suresh Arumuganainar , Kim Yeu‐Chun 
Published: April 2013

ABSTRACTEngineering of algal cells by delivering macromolecules through cell wall and plasma membrane presents many difficulties with the conventional methods. Recent research has shown that a new delivery method, namely cell penetrating peptide (CPP), has the ability to translocate into animal, plant, fungal, and bacterial cells. This study reports the apparent translocation of CPPs into algal cells of Chlamydomonas reinhardtii and the successful delivery of the conjugated fluorochrome. Although translocation efficiency was specific to each CPP studied, pVEC (peptide vascular endothelial cadherin) showed the highest translocation efficiency in comparison with penetratin (PEN), trans‐activating transcriptional (TAT) peptide, and transportan (TRA). The maximum translocation of pVEC into the algal cell was reached in 15 min of incubation at 25°C. More importantly, translocation with pVEC demonstrated an absence of cytotoxicity. Thus, we suggested that pVEC is an attractive candidate for delivering macromolecules into algal cells for use in industrial applications. Biotechnol. Bioeng. 2013;110: 2795–2801. © 2013 Wiley Periodicals, Inc.
Effects of pancreatectomy on nutritional state, pancreatic function and quality of life
Authors: Park J W , Jang J-Y , Kim E-J , Kang M J , Kwon W , Chang Y R , Han I W , Kim S-W 
Published: April 2013

Abstract

Background
There are concerns about the extent of impaired endocrine and exocrine pancreatic function and poor quality of life (QoL) after pancreatectomy, but there is little information from large prospective follow-up studies.

Methods
Consecutive patients undergoing pancreaticoduodenectomy or distal pancreatectomy between 2007 and 2011 were included. Relative bodyweight (RBW), triceps skinfold thickness (TSFT), serum protein, albumin, transferrin, fasting blood glucose, postprandial 2-h glucose (PP2), glycosylated haemoglobin A1c and stool elastase measurements, and European Organization for Research and Treatment of Cancer QLQ-C30 questionnaires were collected serially for 1 year.

Results
Some 136 patients undergoing pancreatic resection completed the study. RBW and TSFT recovered to over 90 per cent of the preoperative value by 12 months, whereas transferrin, albumin and protein had returned to preoperative levels by 3 months. Diabetes mellitus, impaired fasting glucose or raised PP2 was present in 42 of 76 patients at 6 months and 36 of 76 at 12 months. Although steatorrhoea and diarrhoea had mainly resolved by 3 months, stool elastase level decreased after operation and showed no recovery. Nutritional status, pancreatic endocrine function and QoL returned to preoperative levels in 63 (46·3 per cent), 72 (52·9 per cent) and 77 (56·6 per cent) of 136 patients within 6 months of pancreatectomy. Multivariable analysis revealed that age 60 years or more, operation type, chronic pancreatitis and malignant disease had a significant impact on nutritional index, pancreatic function and QoL.

Conclusion
About half of all patients can expect recovery from pancreatectomy after 6 months, but those with risk factors need more careful follow-up and supportive management.
Mid‐term outcomes following endovascular re‐intervention for iliac artery in‐stent restenosis
Authors: Javed Usman , Balwanz Christopher R. , Armstrong Ehrin J. , Yeo Khung‐Keong , Singh Gagan D. , Singh Satinder , Anderson David , Westin Gregory G. , Pevec William C. , Laird John R. 
Published: April 2013

ObjectivesWe sought to evaluate the procedural characteristics and clinical outcomes of endovascular repair for iliac artery (IA) in‐stent restenosis (ISR).BackgroundAn increasing percentage of patients with complex IA occlusive disease are treated with an endovascular approach, but the outcomes of IA‐ISR have not been well described.MethodsWe analyzed all endovascular procedures for treatment of IA‐ISR performed at our institution between July 2006–December 2010. The primary outcome was primary patency, defined as <50% stenosis as assessed by clinical examination and duplex ultrasonography (DUS).ResultsForty‐one lesions in 24 patients who underwent repeated endovascular intervention for treatment of IA‐ISR. Most lesions were unilateral and involved the common IA (66%). The mean length of ISR was 30.1 ± 14.1 mm with type I (focal) and II (diffuse) ISR occurring with the greatest frequency (34% and 39%, respectively). All patients underwent balloon angioplasty; adjunctive stenting zwas performed in 27 (66%) of the lesions. Type II ISR lesions more frequently required stenting (13/16 lesions, P = 0.02 compared with other patterns of ISR). Procedural success was 100% with a mean gain of 0.13 in the ankle‐brachial index (P = 0.001). The 6‐ and 12‐month primary patency rates were 96% and 82%, respectively. The 12‐month primary‐assisted patency rate was 90% with clinically driven target lesion revascularization (TLR) in three patients.ConclusionsEndovascular treatment of IA‐ISR using an approach of balloon angioplasty followed by selective stenting is associated with high‐patency rates and low rates of TLR at 1 year. © 2013 Wiley Periodicals, Inc.
Polymorphism, Fluorescence, and Optoelectronic Properties of a Borazine Derivative
Authors: Kervyn Simon , Fenwick Oliver , Di Stasio Francesco , Shin Yong Sig , Wouters Johan , Accorsi Gianluca , Osella Silvio , Beljonne David , Cacialli Franco , Bonifazi Davide 
Published: April 2013

AbstractWe have prepared a new borazine derivative that bears mesityl substituents at the boron centers and displays exceptional chemical stability. Detailed crystallographic and solid‐state fluorescence characterizations revealed the existence of several polymorphs, each of which showed different emission profiles. In particular, a bathochromic shift is observed when going from the lower‐ to the higher‐density crystal. Computational investigations of the conformational dynamics of borazine 1 in both the gas phase and in the solid state using molecular dynamics (MD) simulations showed that the conformation of the peripheral aryl groups significantly varies when going from an isolated molecule (in which the rings are able to flip over the 90° barrier at RT) to the crystals (in which the rotation is locked by packing effects), thus generating specific nonsymmetric intermolecular interactions in the different polymorphs. To investigate the optoelectronic properties of these materials by fabrication and characterization of light‐emitting diodes (LEDs) and light‐emitting electrochemical cells (LECs), borazine 1 was incorporated as the active material in the emissive layer. The current and radiance versus voltage characteristics, as well as the electroluminescence spectra reported here for the first time are encouraging prospects for the engineering of future borazine‐based devices.