bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Systems Engineering to U.S. Department of Energy Privatization Project Selection at the Hanford Nuclear Reservation
Authors: Layman John S.
Published: November 2014

The privatization efforts at the U.S. Department of Energy's Hanford Nuclear Reservation have been very successful primarily due to a disciplined process for project selection and execution.

Early in the development of Privatization at Hanford, the Department of Energy determined that a disciplined alternatives generation and analysis (AGA) process would furnish the candidate projects with the best probability for success. Many factors had to be considered in the selection of projects. Westinghouse Hanford Company was assigned to develop this process and facilitate the selection of the first round of candidate privatization projects.

Team members for the AGA process were assembled from all concerned organizations and skill groups. Among the selection criteria were legal, financial and technical considerations which had to be weighed.
SYSTEMS ENGINEERING REALISATION
Authors: Grady Jeffrey O. , Jurewicz Ben R. , Long James E. , Mar Brian W. , Morais Bernard G.
Published: November 2014

The systems engineering process as described in many books, however many minor variations may exist, is perceived by most members of INCOSE as an obvious way to pursue the development of solutions to complex problems. At the same time, most members are aware and concerned that few companies practice its precepts with total success. This paper makes the claim that sound system engineering knowledge exists but is not often well applied in practice as a premise of a study to seek out the reasons for this schism with the goal being an eventual closure of it. This paper, therefore, is an introduction to an extended activity planned by the authors.
“Who Needs Traceability Anyway?”
Authors: James Laurence
Published: November 2014

This paper examines the often very dire consequences of poor requirements and information traceability.
Using a Common Information Model as a Methodological Basis for a Tool‐supported Requirements Management Process
Authors: John Gisela , Hoffmann Matthias , Weber Matthias , Nagel Martin , Thomas Carsten
Published: November 2014

The growing complexity of systems and the continuing pressure on reductions in development time and cost can only be tackled if an effective and tool‐supported requirement management process is established. In our view, requirements management is not just part of requirements engineering. Instead, in principle, it is part of all phases of the entire system life‐cycle, ranging from market analysis and top‐level customer requirements to system maintenance, final shutdown, and removal. In this paper, we report on some methodological experiences gained from introducing a tool‐supported requirements management process at DaimlerChrysler Aerospace Airbus. First, we will describe our view of the main process steps in requirements management and the typical roles that people play in a tool‐supported requirements management process. Then, we will introduce the basic parts of a common requirements management information model and discuss how a general common information model helps to support the main process steps in requirements management.
A Framework for Improving the Requirements Engineering Process Effectiveness
Authors: Williams Ddembe , Kennedy Michael
Published: November 2014

This paper presents “research in progress” for a proposed process simulation‐modelling framework for improving the requirements engineering process effectiveness. It presents a framework based on system dynamics model for measuring the RE process performance in terms of quality, cost resources and schedule adherence. The paper describes the factors included in an initial requirements engineering process model and proposes further work based on the main research issues derived from the model. In developing such a model, the research fills an important gap in the requirements engineering process literature and has the potential to provide practising requirements managers with a tool to support policy development and decision‐making in improving process effectiveness. The strength of the proposed model and its advantages over the existing models is its dynamic nature, and its capability to incorporate both hard and soft factors and the understanding gained from explanatory insights from the feedback structures. Preliminary results based on a pilot case study suggest that the process model‐based tool makes a useful contribution for understanding the RE process. Such a tool may be useful in attaining process effectiveness based on a learning and training environment supported by the system dynamics tools.
Case Study on the Use of Scaling Methods for Prioritising Requirements
Authors: Moisiadis Frank
Published: November 2014

There are often not enough resources available to build systems that can do everything the customer wants. Many times it is necessary to prioritise requirements in the face of limited resources. Budget constraints, delivery deadlines, competitor pressure, and gaining or maintaining one's market‐share are all factors that often impact on the delivery schedule for a system. Consequently, the most important requirements need to be found and implemented first. In trying to determine what requirements are most important, many methods are used in practice. All of these methods involve some kind of scaling or rating system. This paper looks into the various scaling systems that are used. A case‐study has been conducted to evaluate three different rating scales on a set of requirements for a library and for a set of car attributes. The findings are quite interesting in that they reveal weaknesses in using particular rating scales. Suggestions are made as to which rating scale to use to prioritise requirements.
ESSI Project ODE: Implementation of an object oriented software development environment
Authors: Ruiz Fernando
Published: November 2014

This paper presents the ODE Project developed by Casbega, a Spanish soft drink bottler and distributor (Coca‐Cola, Fanta, etc.), with the aim of implementing a new Object Oriented software development environment.

ODE Project started in June 1998 and will finish at the end of June 1999. Its realisation is situated to the logistic area. The objective of this project is to prove that the application of a new style of software development is really worthwhile, before extending it to the rest of areas of the company.

In this paper we provide the reader with an information on how we approached the implementation of the OO software development environment and what results we achieved up to date.
2 MIST – A Measurement Selection Tool
Authors: Farr William H. , Crigler John R.
Published: November 2014

This paper describes a tool that is being jointly developed by the INCOSE Measurement Working Group (MWG) and a group at the Naval Surface Warfare Center Dahlgren Division under sponsorship of the Office of Naval Research (ONR). The tool is a database of key measures to be used throughout a complex system development for that system's evaluation and assessment. The tool can be used both by program management and the technical personnel involved in doing the evaluation to identify which measures should be collected covering the project, the system development process, and the system itself.
Metrics and Processes for F‐22 Requirements Management
Authors: Meyer Al
Published: November 2014

The F‐22 Advanced Tactical Fighter Program has documented over 76,000 functional and design requirements in more than 231 hardware and software specifications during its Engineering and Manufacturing Development (EMD) phase of development. Because of the complex and integrated nature of the requirements, it was necessary to develop an automated relational database tool in which to store, track and analyze these requirements.

Besides selecting an electronic tool to use team wide, a process had to be developed for the requirements change process, along with metrics for the tool to generate, in order to monitor the process. The process had to be acceptable and nonintrusive to procedures already established at the three primary contracting companies of Locheed Martin Aeronautical Systems, Lockheed Martin Tactical Aircraft Systems, and Boeing. The metrics needed to be easily collected and provide relevant data to the health and accuracy of the overall database.

This paper documents the criteria which went into tool selection, the procedures established for tool use, and the metrics developed to monitor the process.
The economic evaluation of investments in a Performance Monitoring and Maintenance Management System for transportation companies
Authors: Ludema Ir. Marcel. W.
Published: November 2014

Transportation companies face the problem of recurrent maintenance activities needed during periods the transportation equipment is not near a preferred maintenance facility. By introducing a Performance Monitoring and Maintenance Management System (P3M‐system), the knowledge of these companies concerning performance and maintenance related matters may improve. This knowledge and the continuous data flow from the transportation equipment via a performance and maintenance planning computer program makes it possible for transportation companies to increase the effectiveness of their transportation system. At the same time it may decrease the maintenance costs. This research found, that only a recurrent use of a for the above described situation developed economic evaluation method will provide these transportation companies with the answer of how much they might benefit from an investment in a P3M‐system.
Test and Evaluation as an Integrated Process in IPPD Efforts
Authors: Roe Charles L.
Published: November 2014

Systems engineering of complex systems under IPPD methodology ensures the integration of all products and processes. This approach includes test and evaluation planning, which may occur at several stages during complex system development, i.e., at the subsystem, system, and supersystem levels. The structure of a project under IPPD must include the assignment of responsible teams and the chartered interaction among those teams so that test and evaluation can be performed across the board. This will ensure the integration of all components into a total system to meet project goals.
Ranger Unmanned Air Vehicle (UAV) System & Software Requirements Management ‐ A Case Study
Authors: Engel Avner , Hurvitz Joshua , Winokur Michael
Published: November 2014

This paper describes the System and Software Requirements Management experience and lessons learned during the development of the Ranger Unmanned Air Vehicle (UAV) System. The Ranger Project involved a multi national collaborative effort, which despite its geographical dispersion was able to successfully produce a large scale, real time system with a complex set of requirements, testing stipulations and an extensive set of formal documentation.

Requirements Management (RM), the focus of this study utilized a Commercial‐Off‐The Shelf (COTS) Data Base Management System (DBMS) and an in‐house developed man‐machine front‐end which supervised and controlled the access to the DBMS. These were used to elicit System requirements which were provided to the hardware and software engineers for further decomposition. Requirements, design, and testing documents were generated from the DBMS and from a back‐end document generator.
Understanding Complex Technology Quantitatively: Impact Estimation Tables
Authors: Gilb Tom
Published: November 2014

Impact Estimation (IE) Tables allow you to analyze any technical or organizational idea (design idea) in relation to requirements (objectives) and costs (resources).

IE is a more objective and more quantitative alternative to Quality Function Deployment (QFD) and other similar techniques. IE uses estimates of the percentage impacts of design ideas on requirements and costs. While IE is not a mathematically rigorous approach, the introduction of quantitative data greatly improves clarity and allows simple numeric calculations to determine cost‐to‐benefit ratios for design ideas and, the numeric likelihood of meeting objectives.

IE also supports the planning and control of evolutionary delivery steps.
Comparative local immunogenic potential of scaffolds prepared from porcine cholecyst, jejunum, and urinary bladder in rat subcutaneous model
Authors: Muhamed Jaseer , Revi Deepa , Rajan Akhila , Anilkumar Thapasimuthu V.
Published: November 2014

Extracellular matrices isolated from several mammalian organs/tissues have found several clinical uses as xenografts or implants. However, they may cause complications because of adverse immunologic reactions. Scaffolds that promote favorable graft‐acceptance reaction are preferred for fabricating xenografts. The objective of this study was to evaluate the immunogenic potential of a porcine cholecyst‐derived scaffold (CDS), prepared by a non‐detergent/enzymatic method, in comparison with jejunum and urinary bladder‐derived scaffolds in a rat subcutaneous model. Key graft‐rejection/acceptance reaction was evaluated at the site of implantation by studying the occurrence and/or function of immunocompetent cells in the tissue reaction. There was differential occurrence of M1‐macrophage, M2‐macrophage, T‐helper cells, T‐cytotoxic cells, B‐cells, and mast cells in the tissue reaction and the CDS attracted few cells compared with other scaffolds. Real‐time polymerase chain reaction for evaluating mRNA of functional markers like inducible nitric oxide synthase (M1 macrophage), arginase 1 (M2 macrophage), interferon gamma (TH1 lymphocytes), and interlukin‐4 (TH2 lymphocytes) suggested that the CDS, compared with the scaffolds prepared from small intestine and urinary bladder, elicited M2 macrophage and TH2 lymphocyte polarization that are congenial graft‐acceptance reactions. The results indicated that CDS has less immunogenic potential compared with the scaffolds prepared from jejunum and urinary bladder when used as subcutaneous graft in rats. It was concluded that CDS is a promising animal‐derived xenograft for biomedical application. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1302–1311, 2015.
MS‐2 and T4 phage removal in an anaerobic membrane bioreactor (AnMBR): effect of gas sparging rate
Authors: Fox Rachel , Stuckey David
Published: November 2014

BACKGROUND

The enhanced removal of viruses in wastewater treatments plant is important due to concerns about public health. Bacteriophages (or phages) are often used to model the behavior of pathogenic human viruses as they are similar in size, structure and behavior. This study investigated the removal of phages MS‐2 (25 nm) and T4 (200 nm) in an anaerobic membrane bioreactor (AnMBR) with a membrane pore size of 0.4 µm.

RESULTS

The membrane reactor without biomass was assessed and its log removal was 0.7 ± 0.4 log for the MS‐2 phage, and 2.3 ± 0.2 log for the T4. When anaerobic biomass was added to the reactor the log removal for both phages increased, and this was thought to be due to a complex relationship with the biofilm on the membrane.

CONCLUSIONS

Overall MS‐2 rejections ranged from 1.75 up to 5.5 log, with the highest rejections observed at the highest sparging rates after extensive fouling had occurred. For T4, removal in the AnMBR ranged from 5 log up to complete removal (>log 7). © 2014 Society of Chemical Industry
Brief exposure of embryos to steroids or aromatase inhibitor induces sex reversal in Nile tilapia (Oreochromis niloticus)
Authors: Gennotte Vincent , Mafwila Kinkela Patrick , Ulysse Bernard , Akian Djétouan Dieudonné , Bere Sompagnimdi Frédéric , Tomson Thomas , Mélard Charles , Rougeot Carole
Published: November 2014

This study aimed to develop sex reversal procedures targeting the embryonic period as tools to study the early steps of sex differentiation in Nile tilapia with XX, XY, and YY sexual genotypes. XX eggs were exposed to masculinizing treatments with androgens (17α‐methyltestosterone, 11‐ketotestosterone) or aromatase inhibitor (Fadrozole), whereas XY and YY eggs were subjected to feminizing treatments with estrogen analog (17α‐ethynylestradiol). All treatments consisted of a single or double 4‐hr immersion applied between 1 and 36 hour post‐fertilization (hpf). Concentrations of active substances were 1000 or 2000 μg l−1 in XX and XY, and 2000 or 6500 μg l−1 in YY. Masculinizing treatments of XX embryos achieved a maximal sex reversal rate of 10% with an exposure at 24 hpf to 1000 μg l−1 of 11‐ketotestosterone or to 2000 μg l−1 of Fadrozole. Feminization of XY embryos was more efficient and induced up to 91% sex reversal with an exposure to 2000 μg l−1 of 17α‐ethynylestradiol. Interestingly, similar treatments failed to reverse YY fish to females, suggesting either that a sex determinant linked to the Y chromosome prevents the female pathway when present in two copies, or that a gene present on the X chromosome is needed for the development of a female phenotype. J. Exp. Zool. 323A: 31–38, 2015. © 2014 Wiley Periodicals, Inc.
Kinetics and Mechanistic Approach to the Oxidative Behavior of Biological Anticancer Platinum(IV) Complex toward ‐Asparagine in Acid Medium and the Effect of Copper(II) Catalyst
Authors: FAWZY AHMED
Published: November 2014

The catalytic effect of copper(II) ions toward the oxidation of ‐asparagine (Asn) by an anticancer platinum(IV) complex in the form of hexachloroplatinate(IV) (HCP) has been investigated in aqueous acid medium at the constant ionic strength and temperature. The progress of both uncatalyzed and copper(II)‐catalyzed oxidation reactions has been monitored spectrophotometrically. The stoichiometry in both cases is [Asn]/[HCP] = 1:1. The kinetics of both redox reactions is first order with respect to [oxidant] and less than the unit order in [acid]. The order with respect to [Asn]T decreases from unity in the uncatalyzed path to less than unity in the catalyzed one. The catalyzed path is first order in [CuII]T. Increasing ionic strength and dielectric constant decreases the oxidation rates. The final oxidation products of ‐asparagine are identified as the corresponding aldehyde (α‐formyl acetamide), ammonium ion, and carbon dioxide. Tentative mechanisms of both reactions have been suggested. The appropriate rate laws are deduced. The activation parameters of the uncatalyzed reaction have been evaluated and discussed.
Hemostatic status in liver transplantation: Association between preoperative procoagulants/anticoagulants and postoperative hemorrhaging/thrombosis
Authors: Akamatsu Nobuhisa , Sugawara Yasuhiko , Nakazawa Akiko , Nishioka Yujiro , Kaneko Junichi , Aoki Taku , Sakamoto Yoshihiro , Hasegawa Kiyoshi , Kokudo Norihiro
Published: November 2014

The delicate rebalanced hemostatic status of liver transplant recipients may lead to both hemorrhagic and thrombotic tendencies in this population. The aim of this study was to investigate the association between pretransplant procoagulants/anticoagulants and posttransplant bleeding and thrombosis among living donor liver transplant recipients. The study subjects were 403 consecutive recipients with chronic liver disease. Perioperative variables, including preoperative values for procoagulants and anticoagulants, were assessed to determine their association with posttransplant hemorrhaging and thrombosis. There were 35 hemorrhagic complications (9%) and 21 thrombotic complications (5%). In logistic regression analyses, a higher Model for End‐Stage Liver Disease score (P = 0.01) and a lower fibrinogen value (P < 0.001) were independently associated with hemorrhaging, whereas only a lower protein C value (P < 0.001) was independently associated with thrombosis. In a receiver operating characteristic analysis, a low preoperative protein C value (with the most accurate cutoff value being 25%) was a reliable predictor of thrombotic complications after liver transplantation (area under the curve = 0.921, P < 0.001, sensitivity = 0.9, specificity = 0.8). In conclusion, the decreases in both procoagulants and anticoagulants in liver transplant recipients may additively result in a delicate hemostatic balance and predispose patients to both hemorrhagic and thrombotic complications. A lower preoperative protein C value (<25%) was demonstrated to be a significant and reliable predictor of postoperative thrombotic complications in liver transplant recipients. Liver Transpl 21:258‐265, 2015. © 2014 AASLD.
Impact of multiple transarterial chemoembolization treatments on hepatocellular carcinoma for patients awaiting liver transplantation
Authors: Terzi Eleonora , Ray Kim W. , Sanchez William , Charlton Michael R. , Schmeltzer Paul , Gores Gregory J. , Andrews James C. , Smyrk Thomas C. , Heimbach Julie K.
Published: November 2014

Transarterial chemoembolization (TACE) is a common treatment for patients with hepatocellular carcinoma (HCC) who are awaiting liver transplantation (LT). The aim of this study was to assess the impact of multiple TACE treatments on tumor necrosis, tumor recurrence, and survival in these patients. A retrospective analysis was performed for 104 consecutive patients undergoing LT for HCC from January 2002 to December 2009 who were treated with TACE before LT. The number of TACE treatments was not associated with tumor necrosis in the explant. After a median follow‐up of 69 months (range = 0‐123 months), 14 of the 104 patients (13%) developed recurrent HCC after LT. Recurrence had a significant relationship with a short interval between the diagnosis of HCC and LT (≤6 months) in univariate and multivariate analyses [P = 0.029, odds ratio (OR) = 19.2]. Patients subjected to a single TACE treatment were more likely to experience recurrence, although this finding was not confirmed in the multivariate analysis. No significant relationship was observed between tumor necrosis in the explant and recurrence. The mean overall survival was 102.8 months (95% confidence interval = 94.9‐110.8 months) with 1‐, 3‐, and 5‐year survival rates of 91%, 89%, and 84% respectively. In the univariate survival analysis, the presence of ascites before TACE, a waiting time ≤ 9 months, and tumor characteristics at the pathological examination were statistically associated with shorter survival. In the multivariate analysis, only vascular invasion (P < 0.001, OR = 7.99) remained independently associated with shorter survival. The number of TACE treatments was not associated with survival. In conclusion, multiple TACE treatments were not associated with a higher risk of recurrence or shorter survival. Continued use of TACE should be considered as indicated if the patient and lesions are suitable for retreatment. A shorter waiting time before LT is related to an increased risk of recurrence and decreased survival after LT for HCC. These data could reflect the presence of more aggressive tumor biology and may be useful for guiding organ allocation policy to consider a minimum observation period before LT for regions with shorter wait times. Liver Transpl 21:248‐257, 2015. © 2014 AASLD.
Heating‐Responsive Shape‐Memory Effect in Thermoplastic Polyurethanes with Low Melt‐Flow Index
Authors: Sun Li , Huang Wei Min , Lu Haibao , Lim Kok Jiak , Zhou Ye , Wang Tao Xi , Gao Xiang Yang
Published: November 2014

The heating‐responsive shape‐memory effect (SME) based on melting in two thermoplastic polyurethanes (TPUs) with low melt‐flow index is experimentally investigated. It is revealed that after severe deformation in either tension or impression at room temperature, upon heating to the melting temperature, significant shape recovery is achieved. The underlying mechanism for the heating‐responsive shape recovery (based on melting) in such a type of polymers without crosslinking is proposed. This mechanism is generic and should be applicable to most thermoplastic polymers with a low melt‐flow index.

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Preparation of Epoxy/Jeffamine Networks Modified With Phosphonium Based Ionic Liquids
Authors: Soares Bluma G. , Silva Adriana A. , Pereira Jéssica , Livi Sébastien
Published: November 2014

This study investigates the influence of different ionic liquids (ILs) based on tetraalkyl‐phosphonium cations on the dynamic‐mechanical, ionic conductivity as well as morphology of epoxy resin based on diglycidyl ether of bisphenol A cured with poly(propyleneglycol) bis(2‐aminopropyl ether), aiming to develop new thermosetting systems with confined ionic liquid. The ionic liquids include trihexyl(tetradecyl)‐phosphoniumdicyanamide, trihexyl(tetradecyl) phosphonium‐bis(trifluoromethane‐sulfonyl)imide) and tributyl(tetradecyl) phosphonium‐dodecylbenzenesulfonate. The effect of these ILs on the morphology, dynamic‐mechanical, ionic conductivity and tensile properties of DGEBA networks is investigated.
Arctigenin in combination with quercetin synergistically enhances the antiproliferative effect in prostate cancer cells
Authors: Wang Piwen , Phan Tien , Gordon David , Chung Seyung , Henning Susanne M. , Vadgama Jaydutt V.
Published: November 2014

Scope

We investigated whether a combination of two promising chemopreventive agents arctigenin (Arc) and quercetin (Q) increases the anticarcinogenic potency at lower concentrations than necessary when used individually in prostate cancer.

Methods and results

Androgen‐dependent LAPC‐4 and LNCaP prostate cancer cells were treated with low doses of Arc and Q alone or in combination for 48 h. The antiproliferative activity of Arc was 10‐ to 20‐fold stronger than Q in both cell lines. Their combination synergistically enhanced the antiproliferative effect, with a stronger effect in androgen receptor (AR) wild‐type LAPC‐4 cells than in AR mutated LNCaP cells. Arc demonstrated a strong ability to inhibit AR protein expression in LAPC‐4 cells. The combination treatment significantly inhibited both AR and PI3K/Akt pathways compared to control. A protein array analysis revealed that the mixture targets multiple pathways particularly in LAPC‐4 cells including Stat3 pathway. The mixture significantly inhibited the expression of several oncogenic microRNAs including miR‐21, miR‐19b, and miR‐148a compared to control. The mixture also enhanced the inhibition of cell migration in both cell lines compared to individual compounds tested.

Conclusion

The combination of Arc and Q that target similar pathways, at low physiological doses, provides a novel regimen with enhanced chemoprevention in prostate cancer.
New synthesis on the basis 2‐allyloxy chalcone and NMR studies its some derivatives
Authors: Mamedov I. G. , Bayramov M. R. , Mamedova Y. V. , Maharramov A. M.
Published: November 2014

Synthesis and NMR investigations of cyclohexenone, flavanone, isoxazol and indazole derivatives of (2E)‐3‐[2‐(allyloxy)‐5‐bromophenyl]‐1‐(2‐hydroxy‐5‐methylphenyl)‐2‐propen‐1‐one (I, chalcone) have been carried out. The results confirm the formation of O–H•••O type intramolecular hydrogen bond and intramolecular cyclization in the (2E)‐3‐[2‐(allyloxy)‐5‐bromophenyl]‐1‐(2‐hydroxy‐5‐methylphenyl)‐2‐propen‐1‐one (I), the presence of conformational and keto–enol tautomeric transitions in the 6‐acetyl‐5‐[2‐(allyloxy)‐5‐bromophenyl]‐3‐(2‐hydroxy‐5‐methylphenyl)‐2‐cyclohexen‐1‐one (II), conformational transitions in the 2‐{4‐[2‐(allyloxy)‐5‐bromophenyl]‐3‐methyl‐4.5‐dihydro‐1.2‐benzisoxazol‐6‐yl}‐4‐methylphenol (III) and 2‐{4‐[2‐(allyloxy)‐5‐bromophenyl]‐3‐methyl‐4.5‐dihydro‐1H‐indazol‐6‐yl}‐4‐methylphenol (IV). The conformational and keto–enol tautomerism in the investigated compounds have been also confirmed by chemical methods. Copyright © 2014 John Wiley & Sons, Ltd.
Prehistoric Whale Bone Technology in Southern New Zealand
Authors: Cunliffe E. A. , Brooks E.
Published: November 2014

Whale bone was used by Māori throughout New Zealand prehistory as an industrial resource for the manufacture of a range of artefacts. However, the selection of bone and the methods used to process it are poorly understood. This paper details the analysis of a southern right whale (Eubalaena australis) bone working floor that was excavated from a fifteenth‐century coastal fishing camp at Kahukura, on the southeast coast of New Zealand. The whale bone working floor assemblage, comprising a large quantity of debitage fragments, was used to reconstruct reduction methods and to determine the products being made at the site. Rib bones were the main element being worked, and were reduced longitudinally using a chipping technique. The intensive bone working assemblage at Kahukura represents the by‐products from primary processing. This stage focused on reducing the bones into workable portions so that they could be easily transported to another location, where they were likely further reduced into artefacts. Copyright © 2015 John Wiley & Sons, Ltd.
Intrahepatic fat content correlates with soluble CD163 in relation to weight loss induced by Roux‐en‐Y gastric bypass
Authors: Fjeldborg Karen , Pedersen Steen B. , Møller Holger J. , Rask Peter , Danielsen Allan Vestergaard , Stødkilde‐Jørgensen Hans , Richelsen Bjørn
Published: November 2014

Objective

Soluble CD163 (sCD163) is a new marker of obesity‐related metabolic complications. sCD163 and CD163 mRNA were investigated in relation to the fat distribution at baseline and 12 months after Roux‐en‐Y gastric bypass (RYGB).

Methods

Thirty‐one obese subjects (BMI: 42.3 ± 4.7 kg/m2) were enrolled. Subcutaneous (SAT) and visceral adipose tissue (VAT) volume were determined by MRI, intrahepatic lipid content (IHL) by MR‐spectroscopy, and body composition by DXA. Fasting blood samples and adipose tissue samples were obtained, and ELISA and RT‐PCR were performed.

Results

RYGB‐induced weight loss (36 ± 11 kg) was accompanied by a significant reduction in sCD163 (2.1 ± 0.8 mg/l vs. 1.7 ± 0.7 mg/l), SAT, VAT, and IHL (all, P < 0.001). At baseline, sCD163 was associated with VAT (r = 0.40, P < 0.05) but not with SAT or IHL. Moreover, CD163 mRNA was significantly upregulated in VAT compared with SAT at baseline (P < 0.05) and significantly downregulated in SAT after RYGB (P < 0.001). ΔsCD163 was significantly associated with ΔIHL after RYGB compared with baseline (r = 0.40, P < 0.05).

Conclusions

RYGB‐induced weight loss results in a reduction of sCD163 and CD163 mRNA. The association between ΔsCD163 and ΔIHL may reflect a reduction in sCD163‐producing Kupffer cells in the liver. Moreover, sCD163 may be a marker of “unhealthy” fat distribution in obese subjects.
Investigation of the high velocity impact behavior of nanocomposites
Authors: Pol M. Hossein , Liaghat Gholamhossein
Published: November 2014

In this article, the ballistic behavior of the glass/epoxy/nanoclay hybrid nanocomposites is studied. The fiber glass used is a plain weave 200 g/m2, while the nanoclay is an organically modified montmorillonite nanoclay (Closite 30B). The epoxy resin system is made of Epon 828 as the epoxy prepolymer and Jeffamine D‐400 as the curing agent. 0, 3, 5, 7, and 10 wt% of nanoclay particles are dispersed in the epoxy resin. Ballistic tests are performed using flat‐ended projectiles in impact velocities 134 m/s and 169 m/s. The results show that the energy absorption capability and mechanical properties of the composite can be significantly enhanced by adding nanoparticles. When the impact velocity is 134 m/s, near than the ballistic limit, the most increase in the energy absorption capability is observed in 3 wt% nanoclay while with the impact velocity 169 m/s, beyond the ballistic limit, the highest increase is observed in 10 wt% nanoclay. POLYM. COMPOS., 37:1173–1179, 2016. © 2014 Society of Plastics Engineers
Fiber volume control of composite materials by loss angle
Authors: Yoshida Shuichiro , Kondo Keiichi
Published: November 2014

Fiber volume plays a critical role in achieving stable mechanical and physical properties in composite structures. This study develops a method to control this parameter in carbon fiber reinforced plastics (CFRPs) on the basis of the viscoelastic character of the thermosetting matrix resin. This method relies on the loss angle δ to quantitatively control fiber volume. CFRP flat panels are manufactured at varying initiating times of pressure application depending on the δ value of the CFRP matrix resin. An analysis of the manufactured panels clearly shows that the target fiber volumes can be obtained at an appropriate δ range. Specifically, CFRP fiber volumes can be controlled through the loss angle of the matrix resin. Defining this δ range is very important for establishing mechanically and physically stable CFRP structures. POLYM. COMPOS., 37:1307–1311, 2016. © 2014 Society of Plastics Engineers
Fibro‐porous poliglecaprone/polycaprolactone conduits: synergistic effect of composition and in vitro degradation on mechanical properties
Authors: Patel Harsh N , Garcia Roman , Schindler Carrie , Dean Derrick , Pogwizd Steven M , Singh Raj , Vohra Yogesh K , Thomas Vinoy
Published: November 2014

Blends of poliglecaprone (PGC) and polycaprolactone (PCL) of varying compositions were electrospun into tubular conduits and their mechanical, morphological, thermal and in vitro degradation properties were evaluated under simulated physiological conditions. Generally, mechanical strength, modulus and hydrophilic nature were enhanced by the addition of PGC to PCL. An in vitro degradation study in phosphate‐buffered saline (pH 7.3) was carried out for up to 1 month to understand the hydrolytic degradation effect on the mechanical properties in both the longitudinal and circumferential directions. Pure PCL and 4:1 PCL/PGC blend scaffolds exhibited considerable elastic stiffening after a 1 month in vitro degradation. Fourier transform infrared spectroscopic and DSC techniques were used to understand the degradation behavior and the changes in structure and crystallinity of the polymeric blends. A 3:1 PCL/PGC blend was concluded to be a judicious blend composition for tubular grafts based on overall results on the mechanical properties and performance after a 1 month in vitro degradation study. © 2014 Society of Chemical Industry
1‐(2H‐Tetrazolyl)‐1,2,4‐triazole‐5‐amine(TzTA) – A Thermally Stable Nitrogen Rich Energetic Material: Synthesis, Characterization and Thermo‐Chemical Analysis
Authors: Nimesh Sasidharan , Ang How‐Ghee
Published: November 2014

The targeted high nitrogen energetic material 1‐(2H‐tetrazol‐5‐yl)‐1,2,4‐triazol‐5‐amine (TzTA) was synthesized from 3‐amino‐1,2,4‐triazole via a two‐step procedure using cyanogen bromide and sodium azide. TzTA was prepared in good yields and characterized using analytical (elemental) and spectroscopic (IR, Raman, NMR) techniques. The crystal structure of sulfate salt of the molecule was solved by means of low temperature X‐ray crystallography, which showed the co‐planarity of the two rings. The sulfate salt of the molecule crystallized in monoclinic system P21/n, with a crystal density of 1.856 g cm−3. The thermal stability of the molecule was assessed by DSC. The molecule showed excellent thermal stability better than many known nitrogen rich energetic molecules and showed comparable thermal stability with HMX. Non‐isothermal kinetics was performed on the molecule to derive the activation energy. Constant volume combustion energy was determined using oxygen bomb calorimeter and back calculated the heat of formation. Preliminary insight on the gas generating capability of the molecule was tested by measuring the dynamic pressure generated inside a closed bomb. Dynamic pressure of an oxygen balanced system (TzTA and ADN) was also measured using the Parr dynamic pressure measurement system.
Enhanced quantum efficiency of AlGaN photodetectors by patterned growth
Authors: Knigge A. , Brendel M. , Zeimer U. , Helbling M. , Knauer A. , Brunner F. , Kueller V. , Einfeldt S. , Weyers M.
Published: November 2014

Al0.45Ga0.55N metal–semiconductor–metal photodetectors were grown by MOVPE on planar and on stripe patterned epitaxial laterally overgrown (ELO) AlN/sapphire templates. By comparing devices on different template types, the influence of the average dislocation density, the distribution of dislocations, and composition modulations due to inhomogeneous gallium incorporation on the external quantum efficiency (EQE) were evaluated. The reduction of the average dislocation density from 6 × 109 cm−2 on the planar template to about 2 × 109 cm−2 by ELO increases the EQE. For electron transport perpendicular to the ELO stripes, this increase is about 70%. Due to the stripe‐like dislocation distribution in the absorber layers on ELO templates, the EQE becomes up to a factor of 3 higher than for planar templates, when the electrodes are perpendicular to the ELO stripes and electron transport is along the stripes. Photoconductive gain was found at elevated bias for absorber layers on standard ELO templates with electrodes perpendicular to the ELO stripes. The gain can be attributed to carrier transport in zig‐zag shaped Ga‐rich channels caused by facetted growth on ELO templates. The gain only appears, if the aluminum mole fraction differences Δx are higher than 0.07. At 30 V bias, the EQE of such detectors is more than 3 orders of magnitude higher compared to planar device.
Distribution‐free Phase II CUSUM Control Chart for Joint Monitoring of Location and Scale
Authors: Chowdhury Shovan , Mukherjee Amitava , Chakraborti Subhabrata
Published: November 2014

A single distribution‐free (nonparametric) Shewhart‐type chart on the basis of the Lepage statistic is well known in literature for simultaneously monitoring both the location and the scale parameters of a continuous distribution when both of these parameters are unknown. In the present work, we consider a single distribution‐free cumulative sum chart, on the basis of the Lepage statistic, referred to as the cumulative sum‐Lepage (CL) chart. The proposed chart is distribution‐free (nonparametric), and therefore, the in‐control properties of the chart remain invariant and known for all continuous distributions. Control limits are tabulated for implementation of the proposed chart in practice. The in‐control and out‐of‐control performance properties of the cumulative sum‐Lepage (CL) chart are investigated through simulation studies in terms of the average, the standard deviation, the median, and some percentiles of the run length distribution. Detailed comparison with a competing Shewhart‐type chart is presented. Several existing cumulative sum charts are also considered in the performance comparison. The proposed CL chart is found to perform very well in the location‐scale models. We also examine the effect of the choice of the reference value (k) on the performance of the CL chart. The proposed chart is illustrated with a real data set. Summary and conclusions are presented. Copyright © 2014 John Wiley & Sons, Ltd.
1‐Adamantanethiol as a versatile nanografting tool
Authors: Drexler Chad I. , Causey Corey P. , Mullen Thomas J.
Published: November 2014

Strategies to regulate the self‐assembly of adsorbates to create surface structures with molecular‐scale features and organization are of broad interest to nanoscience, biochemistry, and engineering. One approach utilizes molecules with tailored intermolecular interaction strengths and topologies to direct molecular self‐assembly as exemplified by the adsorption of 1‐adamantanethiol molecules on Au{111} substrates. 1‐Adamantanethiolate self‐assembled monolayers exhibit decreased packing densities and weaker intermolecular interaction strengths than n‐alkanethiolate self‐assembled monolayers, which result in their complete displacement upon exposure to n‐alkanethiol molecules. Herein, we explore the capabilities of the atomic force microscopy‐based lithographic technique, nanografting, to fabricate chemical patterns comprised of 1‐adamantanethiolate monolayers. Positive 1‐adamantanethiolate patterns are generated by nanografting 1‐adamantanethiol molecules into preexisting n‐alkanethiolate self‐assembled monolayers, and negative 1‐adamantanethiolate patterns are created by nanografting n‐alkanethiol molecules into preexisting 1‐adamantanethiolate self‐assembled monolayers. The patterned 1‐adamantanethiolate regions are displaced upon exposure to solutions of n‐alkanethiol molecules. This two‐step nanografting‐displacement strategy minimizes pattern dissolution as 1‐adamantanethiol molecules do not intercalate into the preexisting self‐assembled monolayer during nanografting. 1‐Adamantanethiol can be utilized create high‐resolution sacrificial chemical patterns with feature sizes beyond those afforded other 1‐adamantanethiol patterning strategies for applications such as resists for metallic and organic structures. SCANNING 37:6–16, 2015. © 2014 Wiley Periodicals, Inc.
Experimental evaluation of various register‐pressure‐reduction heuristics
Authors: Shobaki Ghassan , Sakka Laith , Abu Rmaileh Najm Eldeen , Al‐Hamash Hasan
Published: November 2014

Minimizing the amount of spill code is still an open problem in code generation and optimization. The amount of spill code depends on both the register allocation algorithm and the pre‐allocation instruction scheduling algorithm that controls the register pressure. In this paper, we focus on the impact of pre‐allocation instruction scheduling on the amount of spill code. Many heuristic techniques have been proposed to do instruction scheduling with the objective of minimizing register pressure and consequently the amount of spill code. However, the performance of these heuristic techniques has not been studied relative to optimality on real large‐scale programs. In this paper, we present an experimental study that evaluates the performance of several pre‐allocation scheduling heuristics. The evaluation involves computing an experimental lower bound on the size of gap between each heuristic's performance and optimal performance. We also propose a simple heuristic technique based on a specific permutation of two basic priority schemes and experimentally evaluate the performance of this technique compared with other heuristics, including the heuristics implemented in the LLVM open‐source Compiler. The evaluation is carried out by running SPEC CPU2006 on real x86‐64 hardware and measuring both the amount of spill code and the execution time. The results of our study show that the proposed heuristic technique gives better overall performance than LLVM's best heuristic on x86‐64, although it produces slightly more spilling. The proposed heuristic has better overall performance, because it achieves a better balance between register pressure and instruction‐level parallelism (ILP). This result shows the importance of ILP in pre‐allocation scheduling even on out‐of‐order machines. Furthermore, the results of the study show that there is a large gap between the performance of any of the studied heuristics and optimal performance; even the best heuristic in the study produces significantly more spill code than the optimal amount. This experimental result quantifies the intuitive belief that it is unlikely to find a heuristic that works well in all cases, thus showing the need for more rigorous solutions using combinatorial approaches. The paper discusses the challenges and complexities that are involved in developing such rigorous solutions. Copyright © 2014 John Wiley & Sons, Ltd.
Directed test suite augmentation: an empirical investigation
Authors: Xu Zhihong , Kim Yunho , Kim Moonzoo , Cohen Myra B. , Rothermel Gregg
Published: November 2014

Test suite augmentation techniques are used in regression testing to identify code elements in a modified program that are not adequately tested and to generate test cases to cover those elements. A defining feature of test suite augmentation techniques is the potential for reusing existing regression test suites. Our preliminary work suggests that several factors influence the efficiency and effectiveness of augmentation techniques that perform such reuse. These include the order in which target code elements are considered while generating test cases, the manner in which existing regression test cases and newly generated test cases are used, and the algorithm used to generate test cases. In this work, we present the results of two empirical studies examining these factors, considering two test case generation algorithms (concolic and genetic). The results of our studies show that the primary factor affecting augmentation using these approaches is the test case generation algorithm utilized; this affects both cost and effectiveness. The manner in which existing and newly generated test cases are utilized also has a substantial effect on efficiency and in some cases a substantial effect on effectiveness. The order in which target code elements are considered turns out to have relatively few effects when using concolic test case generation but in some cases influences the efficiency of genetic test case generation. The results of our first study, on four relatively small programs using a large number of test suites, are supported by our second study of a much larger program available in multiple versions. Together, the studies reveal a potential opportunity for creating a more cost‐effective hybrid augmentation approach leveraging both concolic and genetic test case generation techniques, while appropriately utilizing our understanding of the factors that affect them. Copyright © 2014 John Wiley & Sons, Ltd.
Geometric analysis of distributed power control and Möbius MAC design
Authors: Tong Zhen , Haenggi Martin
Published: November 2014

This paper presents a geometric analysis of the convergence condition for the Foschini–Miljanic power control algorithm. The Möbius transform is exploited for the first time to analyze the convergence condition of the power control algorithm. A novel MAC scheme based on the Möbius transform is proposed for the link scheduling problem and proven to improve spatial reuse by scheduling links in pairs if possible. The peak power constraint of wireless networks is analyzed theoretically, and applications to random networks are explored in detail. Observations from the analysis of peak power constraints are also applied to the design of the MAC scheme (Möbius MAC) to improve the convergence speed and system performance. Simulation results show that our Möbius MAC can roughly double the performance of CSMA in terms of transport density. Applications to cognitive networks and heterogeneous networks are discussed. Copyright © 2014 John Wiley & Sons, Ltd.
A cross‐layer study for application‐aware multi‐hop cognitive radio networks
Authors: Shu Zhihui , Qian Yi , Yang Yaoqing , Sharif Hamid
Published: November 2014

Satisfying the different requirements of applications is important in multi‐hop cognitive radio networks, because the spectrum resources change dynamically and the requirements for various applications could be very different. In this paper, we propose new schemes of channel allocation and route selection for real‐time and non‐real‐time applications to tackle this challenge. Our scheme is flexible so that it can adapt to the different application requirements, and it can provide enough throughput while maintaining the packet loss rate and transmission rate requirements. First, we give the network model in a cognitive radio network environment, and show how to calculate the capacity of the route in multi‐hop cognitive radio networks. Second, we formulate optimization problems to fulfill the rate requirements of different applications for each unicast session. We also consider the primary user activities, channel availability, interface and interference constraint. We propose the corresponding routing and channel allocation schemes for different application scenarios. Third, we propose an admission control scheme to study the impact of application requirements for multiple sessions in cognitive radio networks. Finally, we implement simulations to show the performance of our schemes and compare them with existing schemes. Copyright © 2014 John Wiley & Sons, Ltd.