bluuebunny/crossref_metadata_2025 huggingface dataset:
Guideline Implementation: Sterile Technique
Authors: Link Terri
Published: September 2019

Establishing and maintaining a sterile field to help prevent surgical site infections requires specific knowledge and skills and is among the most important responsibilities of the perioperative RN. Perioperative RNs should remain vigilant in monitoring the sterile field, communicate when a break in sterile technique occurs, and collaborate with other surgical team members to correct the break in technique. The AORN “Guideline for sterile technique” provides guidance to perioperative personnel on the principles and processes of sterile technique. This article elaborates on key takeaways from the guideline, including using sterile technique when donning sterile gowns and gloves, delivering sterile items to the sterile field, using drapes to establish a sterile field, and maintaining the sterile field. Perioperative RNs should review the complete guideline for additional information and for guidance when writing and updating policies and procedures.
Electrophysiological correlates of masked repetition and conceptual priming for visual objects
Authors: Li Bingbing , Gao Chuanji , Wang Juan
Published: September 2019

Background

Previous studies have investigated the time course of visual object processing using event‐related potential (ERP) and the masked repetition priming paradigm. However, it is unclear how the ERP correlates associated with masked repetition priming differentiate from masked conceptual priming of visual objects.

Method

The present study used semantically related picture pairs of visual objects to compare the ERPs associated with masked repetition and conceptual priming of visual objects.

Results

The results revealed that masked repetition priming was associated with N/P190 and N400 effects, whereas masked conceptual priming was only associated with N400 effect. Moreover, the topography of repetition N/P190 effect was different from repetition and conceptual N400 effects, whereas the topography of repetition N400 effect was similar to conceptual N400 effect.

Conclusions

These results indicated that masked repetition and conceptual priming were associated with spatiotemporally different ERP effects and that the N400 of visual objects was sensitive to automatic semantic spreading.
Synthesis of Disulfide‐Bridged N‐Phenyl‐N′‐(alkyl/aryl/heteroaryl)urea Derivatives and Evaluation of Their Antimicrobial Activities
Authors: Dilem Doğan Şengül , Buran Sümeyye , Gözde Gündüz Miyase , Özkul Ceren , Siva Krishna Vagolu , Sriram Dharmarajan
Published: September 2019

The discovery of new antimicrobial agents is extremely needed to overcome multidrug‐resistant bacterial and tuberculosis infections. In the present study, eight novel substituted urea derivatives (10a–10h) containing disulfide bond were designed, synthesized and screened for their in vitro antimicrobial activities on standard strains of Gram‐positive and Gram‐negative bacteria as well as on Mycobacterium tuberculosis. According to the obtained results, antibacterial effects of the compounds were found to be considerably better than their antimycobacterial activities along with their weak cytotoxic effects. Molecular docking studies were performed to gain insights into the antibacterial activity mechanism of the synthesized compounds. The interactions and the orientation of compound 10a (1,1′‐((disulfanediylbis(methylene))bis(2,1‐phenylene))bis(3‐phenylurea)) were found to be highly similar to the original ligand within the binding pocket E. faecalis β‐ketoacyl acyl carrier protein synthase III (FabH). Finally, a theoretical study was established to predict the physicochemical properties of the compounds.
Lewis Acid and Base Catalysis of YNbO4 Toward Aqueous‐Phase Conversion of Hexose and Triose Sugars to Lactic Acid in Water
Authors: Kim Minjune , Ronchetti Silvia , Onida Barbara , Ichikuni Nobuyuki , Fukuoka Atsushi , Kato Hideki , Nakajima Kiyotaka
Published: September 2019

Amphoteric YNbO4 was synthesized by the simple coprecipitation using (NH4)3[Nb(O2)4] and Y(NO3)3, and examined as a new solid acid‐base bifunctional catalyst for various reactions including aqueous‐phase conversion of glucose to lactic acid. After drying the white precipitate at 353 K for 3 h, the resultant oxide is an amorphous YNbO4 with high densities of Lewis acid sites (0.18 mmol g−1) and base sites (0.38 mmol g−1). Negatively‐charged lattice oxygen of amorphous YNbO4 functioned as Lewis base sites that promote a Claisen‐Schmidt‐type condensation reaction with acetylacetone and benzaldehyde with comparable activity to reference catalysts. Amorphous YNbO4 can also be applicable to the production of lactic acid from glucose in water, which gives relatively high yields (19.6 %) compared with other reference catalysts. Mechanistic studies using glucose‐1‐d and 2H nuclear magnetic resonance spectroscopy (NMR) revealed that YNbO4 first converts glucose to two carbohydrates (glyceraldehyde and pyruvaldehyde) through dehydration via the formation of 3‐deoxyglucosone and subsequent retro‐aldolization, and these intermediates are then converted to lactic acid by both dehydration and isomerization through hydride transfer.
Elucidation of the Mechanism of Silver‐Catalyzed Inverse Electron‐Demand Diels‐Alder (IEDDA) Reaction of 1,2‐Diazines and Siloxy Alkynes
Authors: Avcı Öyküm Naz , Catak Saron , Dereli Büşra , Aviyente Viktorya , Dedeoglu Burcu
Published: September 2019

Density functional theory (DFT) calculations were utilized to reveal the effect of highly efficient transition metal catalysis in inverse electron demand Diels‐Alder (IEDDA) reactions. The silver‐catalyzed IEDDA reactions of 1,2‐diazines and siloxy alkynes were investigated to highlight the effect of the catalyst and its mode of action. Two different reaction pathways, concerted and stepwise, were explored as well as the uncatalyzed reaction. Computations elucidate the details of the highly efficient Ag catalyst in IEDDA reaction, and are consistent with previous experimental studies. The mode of action for the catalyst is fully revealed and its specific effect on the regioselectivity/specificity of the reaction is established.
The Key Role of Water Activity for the Operating Behavior and Dynamics of Oxygen Depolarized Cathodes
Authors: Röhe Maximilian , Botz Alexander , Franzen David , Kubannek Fabian , Ellendorff Barbara , Öhl Denis , Schuhmann Wolfgang , Turek Thomas , Krewer Ulrike
Published: September 2019

Advanced chlor‐alkali electrolysis with oxygen depolarized cathodes (ODC) requires 30 % less electrical energy than conventional hydrogen‐evolution‐based technology. Herein, we confirm that the activities of hydroxide and water govern the ODC performance and its dynamics. Experimental characterization of ODC under varying mass transfer conditions on the liquid side reveals large differences in the polarization curves as well as in potential step responses of the electrodes. Under convective transport in the liquid electrolyte, the ODC is not limited by mass transfer in its current density atj>3.9 kA m−2, whereas transport limitations are already reached atj≈1.3 kA m−2with a stagnant electrolyte. Since gas phase conditions do not differ significantly between the measurements, these results are in contrast the common assumption that oxygen supply determines ODC performance. A dynamic model reveals the strong influence of the electrolyte mass transfer conditions on oxygen availability and thus performance. Dynamic responses of the current density to step‐wise potential changes are dominated by the mass transport of water and hydroxide ions, which is by orders of magnitude faster with convective electrolyte flow. Without convective liquid electrolyte transport, a high accumulation of hydroxide ions significantly lowers the oxygen solubility. Thus, a fast mass transport of water and hydroxide is essential for high ODC performance and needs to be ensured for technical applications. The predicted accumulation of ions is furthermore validated experimentally by means of scanning electrochemical microscopy. We also show how the outlined processes can explain the distinctively different potential step responses with and without electrolyte convection.
Molecular Electrocatalysts for the Hydrogen Evolution Reaction: Input from Quantum Chemistry
Authors: Barrozo Alexandre , Orio Maylis
Published: September 2019

In the pursuit of carbon‐free fuels, hydrogen can be considered as an apt energy carrier. The design of molecular electrocatalysts for hydrogen production is important for the development of renewable energy sources that are abundant, inexpensive, and environmentally benign. Over the last 20 years, a large number of electrocatalysts have been developed, and considerable efforts have been directed toward the design of earth‐abundant, first‐row transition‐metal complexes capable of promoting electrocatalytic hydrogen evolution reaction (HER). In this context, numerical approaches have emerged as powerful tools to study the catalytic performances of these complexes. This review covers some of the most significant theoretical mechanistic studies of biomimetic and bioinspired homogeneous HER catalysts. The approaches employed to study the free energy landscapes are discussed and methods used to obtain accurate estimates of relevant observables required to study the HER are presented. Furthermore, the structural and electronic parameters that govern the reactivity, and are necessary to achieve efficient hydrogen production, are discussed in view of future research directions.
Population genetic analysis of the domestic Bactrian camel in China by RAD‐seq
Authors: Liu Chenmiao , Chen Huiling , Ren Zhanjun , Zhang Chengdong , Yang Xuejiao
Published: September 2019

Restriction site‐associated DNA sequencing (RAD‐seq) is one of the most effective high‐throughput sequencing technologies for SNP development and utilization and has been applied to studying the origin and evolution of various species. The domestic Bactrian camels play an important role in economic trade and cultural construction. They are precious species resources and indispensable animals in China's agricultural production. Recently, the rapid development of modern transportation and agriculture, and the deterioration of the environment have led to a sharp decline in the number of camels. Although there have been some reports on the evolution history of the domestic Bactrian camel in China, the origin, evolutionary relationship, and genetic diversity of the camels are unclear due to the limitations of sample size and sequencing technology. Therefore, 47 samples of seven domestic Bactrian camel species from four regions (Inner Mongolia, Gansu, Qinghai, and Xinjiang) were prepared for RAD‐seq analysis to study the evolutionary relationship and genetic diversity. In addition, seven domestic Bactrian camel species are located in different ecological zones, forming different characteristics and having potential development value. A total of 6,487,849 SNPs were genotyped. On the one hand, the filtered SNP information was used to conduct polymorphism mapping construction, LD attenuation analysis, and nucleotide diversity analysis. The results showed that the number of SNPs in Dongjiang camel was the highest, the LD coefficient decayed the fastest, and the nucleotide diversity was the highest. It indicates that Dongjiang camel has the highest genetic diversity. On the other hand, the filtered SNPs information was used to construct the phylogenetic tree, and FST analysis, inbreeding coefficient analysis, principal component analysis, and population structure analysis were carried out. The results showed that Nanjiang camel and Beijiang camels grouped together, and the other five Bactrian camel populations gathered into another branch. It may be because the mountains in the northern part of Xinjiang and the desert in the middle isolate the two groups from the other five groups.
Divergent color signals from homologous unfeathered ornaments in two congeneric grouse
Authors: Gould Geoffrey M. , Carter Gerald G. , Augustine Jacqueline K.
Published: September 2019

Color‐based visual signals are important aspects of communication throughout the animal kingdom. Individuals evaluate color to obtain information about age and condition and to behave accordingly. Birds display a variety of striking, conspicuous colors and make ideal subjects for the study of color signaling. While most studies of avian color focus on plumage, bare unfeathered body parts also display a wide range of color signals. Mate choice and intrasexual competitive interactions are easily observed in lekking grouse, which also signal with prominent unfeathered color patches. Most male grouse have one pair of colorful bare part ornaments (combs), and males of several species also have inflatable air sacs in their throat. Previous studies have mostly focused on comb color and size, but little is known about the signaling role of air sac color. We measured comb size and the color properties of combs and air sacs in the Lesser and Greater Prairie‐Chickens (Tympanuchus pallidicinctus and T. cupido, respectively), and investigated whether these properties varied with age and mass. We found that mass predicted color properties of air sacs and that age predicted comb size in the Greater Prairie‐Chicken, suggesting that these ornaments indicate condition dependence. No conclusive relationships between color and age or size were detected in the Lesser Prairie‐Chicken. Color properties of both ornaments differed between the two species. Further research is needed to determine mechanisms that link condition to color and whether the information advertised by color signals from these ornaments is intended for males, females, or both.
Synthesis, Molecular Structures and Electrochemical Investigations of [FeFe]‐Hydrogenase Biomimics [Fe2(CO)6‐n(EPh3)n(µ‐edt)] (E = P, As, Sb; n = 1, 2)
Authors: Ghosh Shishir , Rahaman Ahibur , Orton Georgia , Gregori Gregory , Bernat Martin , Kulsume Ummey , Hollingsworth Nathan , Holt Katherine B. , Kabir Shariff E. , Hogarth Graeme
Published: September 2019

A series of ethane‐dithiolate (edt = S(CH2)2S) complexes [Fe2(CO)5(EPh3)(µ‐edt)] and [Fe2(CO)4(EPh3)2(µ‐edt)] (E = P, As, Sb), biomimics of the core of [FeFe]‐hydrogenases, have been prepared and structurally characterised. The introduced ligand(s) occupies apical sites lying trans to the iron‐iron bond. NMR studies reveal that while in the mono‐substituted complexes the Fe(CO)3 moiety undergoes facile trigonal rotation, the Fe(CO)2(PPh3) centres do not rotate on the NMR timescale. The reductive chemistry has been examined by cyclic voltammetry both in the presence and absence of CO and the observed behavior is found to be dependent upon the nature of the substituents. With L = CO or SbPh3 potential inversion is seen leading to a two‐electron reduction, while for others (L = PPh3, AsPh3) a quasi‐reversible one‐electron reduction is observed. Protonation studies reveal that [Fe2(CO)5(PPh3)(µ‐edt)] is only partially protonated by excess HBF4·Et2O, thus ruling complexes [Fe2(CO)5(EPh3)(µ‐edt)(µ‐H)]+ out as a catalytic intermediates, but [Fe2(CO)4(PPh3)2(µ‐edt)] reacts readily with HBF4·Et2O to produce [Fe2(CO)4(PPh3)2(µ‐edt)(µ‐H)]+. While all new complexes are catalysts for the reduction of protons in MeCN, their poor stability and relatively high reduction potentials does not make them attractive in this respect.
Photolysis and Pyrolysis of Phenyltetrazoles: Formation of Phenylcarbodiimide, N‐Phenylnitrile Imine, Phenylnitrene, Indazole, and Fulvenallene
Authors: Zhao Xiaofang , Liu Qian , Feng Ruijuan , Zeng Xiaoqing , Wentrup Curt
Published: September 2019

Photolysis of 1‐phenyltetrazole 2b at either 193 or 266 nm in a Ne matrix as well as flash vacuum pyrolysis (FVP) of the same compound with isolation of the products in Ne matrix generate phenylcarbodiimide PhN=C=NH 6 very efficiently as the principal product in an almost pure state. Minor amounts of phenyl azide 8 and 1‐azacyclohepta‐1,2,4,6‐tetraene 10, the product of ring expansion of phenylnitrene, are also formed, and the amounts of both substances increase as a function of photolysis time. The photolysis of 2‐phenyltetrazole 1b in a Ne matrix at 266 nm for 0.5 min generates the allenic N‐phenylnitrile imine PhN=N(+)=CH(–) 3b, absorbing strongly and cleanly at 2021 cm–1 in the IR spectrum. At longer photolysis times peaks ascribed to phenyl azide, phenylnitrene, 1‐azacycloheptatetraene, and phenylcarbodiimide 6 become prominent. FVP of 2‐phenyltetrazole yields indazole 15 as the major product together with a small amount of phenylcarbodiimide 6. Indazole formation is ascribed to cyclization of the nitrile imine in the ground state. It is not formed on FVP of 1‐phenyltetrazole in agreement with the computational result that the thermodynamically most favourable path for rearrangement of the putative N‐phenylimidoylnitrene 5b yields phenylcarbodiimide 6 rather than phenylnitrile imine 3b. Further pyrolysis of indazole affords a minor yield of fulvenallene 18.
Humidity‐Mediated Synthesis of Highly Luminescent and Stable CsPbX3 (X = Cl, Br, I) Nanocrystals
Authors: Mamgain Swati , Kunnathodi Vighnesh , Yella Aswani
Published: September 2019

Herein, the synthesis of CsPbX3 nanocrystals (NCs) is reported, and the effect of humidity during the synthesis of perovskite NCs is investigated. Generally, lead halide perovskite NCs degrade very quickly in the presence of moisture. Contrary to previous observations, it is found that the CsPbX3 (X = Cl, Br, I) NCs synthesized in the presence of an optimal amount of humidity show higher stability and significantly improved optical properties. At optimum humidity, it is found that water vapor helps in healing the surface defects commonly present on the CsPbX3 NCs, reduces the nonradiative pathways, and leaves behind the nearly perfect unit cell of CsPbX3 in the solution. Due to the reduction in the surface states, this simple protocol increases photoluminescence quantum yield (PLQY) of NCs by more than 90%. CsPbBr3 NCs synthesized at 30% relative humidity (RH) conditions retain their phase, shape, and size for more than 1 year with negligible reduction in PLQY under 65% RH conditions. Similar findings are observed for CsPbI3 NCs, where the NCs are stable for 2 months. This synthesis approach offers a new pathway to synthesize high‐quality perovskite NCs with excellent optical properties and outstanding stability for optoelectronic applications.
Simulation study on the flow field of guide vane and impeller of turbo expander
Authors: Liu Bingcheng , Wang Shaoyi , Zhang Mengmeng , Liu Ning , Wang Chuanwei , Jia Wenguang
Published: September 2019

In the face of the current energy shortage, organic Rankine cycle (ORC) technology is a way to make efficient use of energy, especially geothermal energy. As the core component of an ORC system, a turbo expander can achieve a high conversion efficiency for geothermal energy and has good development prospects. For low temperature geothermal energy such as 95°C water, R245fa could be chosen as the working fluid. Through preliminary thermal calculations and the MATLAB programming method, the main thermal performance parameters and the aerodynamic parameters, structural parameters, and three‐dimensional modeling of the guide vane and impeller were obtained. The design of the turbo expander was modeled and meshed by the Workbench module using the ANSYS software, and the internal flow path of the expander was numerically simulated by the CFX module. The results showed that there was a small range of wake loss at the trailing edge of the vane flow; impact loss and wake loss occurred at the leading and trailing edges of the impeller blades. At the 30% relative chord strength of the impeller, there was excessive expansion, resulting in a local low‐pressure area and a secondary flow from the hub to the rim.
Effect of boiling and roasting on the physicochemical properties of Djansang seeds (Ricinodendron heudelotii)
Authors: Kinge Emmanuel Edie , Tonfack Djikeng Fabrice , Karuna Mallampalli Sri Lakshmi , Zambou Ngoufack François , Womeni Hilaire Macaire
Published: September 2019

This study was aimed at determining the effect of boiling and roasting on physicochemical properties of Djansang seeds. Dried Djansang seeds were divided into three groups: one group was boiled for 5, 10, and 15 min; another group was traditionally roasted for 5, 10, and 15 min, and the last group was left unprocessed and served as the control. Polyphenols were extracted from the processed seeds using the maceration method, and their content and antioxidant activity were evaluated. Oils were extracted from the dried seeds by Maceration method, and the quality was analyzed by determining their peroxide value (PV), thiobarbituric acid value (TBA), iodine value (IV), and acid value (AV). The changes in proximate composition and mineral content of the processed samples were also evaluated using standard methods. Results showed that traditional roasting significantly decreases (p < .05) the polyphenol content and antioxidant activity of Djansang seeds as compared to boiling. The analysis of oil showed that traditional roasting and boiling significantly reduce the quality of Djansang seed oil (PV: 10.85–38.49 meq O2/kg; TBA: 1.80–3.20 ppm; AV: 0.28%–0.82%; and IV: 104.27–98.11 g I2/g for roasted samples, and PV: 10.85–27.52meq O2/kg; TBA: 1.45–2.28 ppm; AV: 0.56%–0.96%; and IV: 105.87–102.96 g I2/g for boiled samples) compared to the control (PV: 9.96 meq O2/kg; TBA: 1.01 ppm; AV: 0.11%; and IV: 104.83 g I2/g) and that traditionally roasted samples were the most affected. The proximate and mineral composition of Djansang was also affected during processing. Boiling for 5 and 10 min (BNS 5 min and 10 min) and traditional roasting for 5 min (TRNS 5 min) appear to be the best processing methods of Djansang for production of Djansang‐based foods like Djansang sauce.
An Evaluation Ontology Applied to Connected Vehicle Security Assurance
Authors: Powley Stephen , Perry Simon , Holt Jon , Bryans Jeremy
Published: September 2019

Connected vehicles have great potential to benefit society, yet create huge challenges. Vehicles, infrastructure and enterprise activities combine to form massively complex systems of systems (SoSs) that are vulnerable to cyber‐attacks. Security is ill‐defined, making it difficult to achieve a consistent, common understanding of security capabilities across the diverse industries that collaborate to develop connected vehicles. Rigorous evaluation is essential for developing strong security assurance cases. This paper contributes a model‐based systems engineering (MBSE) ontology that enables integrated evaluation processes in enterprise SoSs. The Evaluation Ontology allows diverse types of evaluation to be captured in a single integrated model. A connected vehicle security story is presented to demonstrate the value of the approach. Benefits include enhanced business intelligence that can provide a quantifiable, reportable level of confidence in security‐related processes and technologies. Further work will extend the ontology to develop a customisable suite of enabling patterns for security.
Integrating Program/Project Management and Systems Engineering in Practice
Authors: Hahn Heidi Ann , Hodges Ann L.
Published: September 2019

Two practitioners who have experience integrating program/project management and systems engineering conducted two workshops titled ‘Integrating Systems Engineering, Project Management, and Quality Management’ as an INCOSE Enchantment Chapter tutorial and at the 2018 International Symposium (IS18), respectively. The workshops included presentations by the researchers about their organization's integration implementations followed by small group discussion exercises on topics/issues to consider when making integration decisions. Discussion topics were drawn from Rebentisch (Ed., 2017) and included motivations to integrate, organizational environments that support or inhibit integration, influencers and influence, integration metrics, and success and failure contributors. Each exercise concluded with out‐briefs of the small groups' observations, analyses, and recommendations to the collective. A synthesis of these observations, analyses, and recommendations provide the bases for this paper.
Agile Systems Engineering Life Cycle Model for Mixed Discipline Engineering
Authors: Dove Rick , Schindel Bill
Published: September 2019

This article focuses on six recent understandings that have crystalized from INCOSE's Agile Systems Engineering Life Cycle Model (ASELCM) discovery project. The ASELCM project analyzed effective agile systems engineering processes in 3‐day structured analysis workshops hosted by organizations that wanted deeper understandings of what works, why it works, and how to apply those understandings across a broader base. Four case studies arising from these workshops have been published. This article cannot cover everything of interest that was discovered, but will expose six key findings: a problem‐space characterization heuristic, an asynchronous/concurrent life cycle model framework, a set of nine systems engineering operating principles, an encompassing pattern of three concurrent behavioral systems operating simultaneously in agile systems engineering, the concept of information debt, and general agile systems engineering response requirements.
Systems Engineering–Software Engineering Interface for Cyber‐Physical Systems
Authors: Sheard Sarah , Pafford Michael E. , Phillips Mike
Published: September 2019

Almost all of today's man‐made mechanical and electronic systems are actually cyberphysical systems (CPSs). Formerly physical systems, from rockets to hair dryers and faucets, gain capabilities from software sensing, calculating, and control. Although some software will remain mostly divorced from physical items (e.g., cloud systems), much complex software will control, sense, and communicate with physical systems, which are then called CPSs. Although many systems engineers did not come to the discipline from a software background, CPSs still need systems engineering. Additionally, software engineers must step out of their “subsystem” box and work with systems engineers to build tomorrow's systems. To enable that, systems engineers should continue to apply systems engineering principles, including continuous learning (especially about software) and coordinating (including teaching software engineers about systems engineering). The time is now to take on new behaviors to meet the challenges of CPSs. Systems engineers must work alongside software engineers to reach the joint goal of system success.
A Concept for Set‐based Design of Verification Strategies
Authors: Xu Peng , Salado Alejandro
Published: September 2019

In current practice, a verification strategy is defined at the beginning of an acquisition program and is agreed upon by customer and contractor at contract signature. Hence, the resources necessary to execute verification activities at various stages of the system development are allocated and committed at the beginning, when a small amount of knowledge about the system is available. However, contractually committing to a fixed verification strategy at the beginning of an acquisition program fundamentally leads to suboptimal acquisition performance. Essentially, the uncertain nature of system development will make verification activities that were not previously planned necessary, and will make some of the planned ones unnecessary. In order to cope with these challenges, this paper presents an approach to apply set‐based design to the design of verification activities to enable the execution of dynamic contracts for verification strategies, ultimately resulting in more valuable verification strategies than current practice.
Appreciative Methods Applied to the Assessment of Complex Systems
Authors: Watson Michael , Anway Randall , McKinney Dorothy , Rosser Larri Ann , MacCarthy John
Published: September 2019

Complex systems have characteristics that challenge traditional systems engineering processes and methods. These characteristics have been defined in various ways. INCOSE has previously identified characteristics of complex systems and potential methods to deal with complexity in system development. The purpose of this paper is to provide definitions and describe distinguishing characteristics of complexity using example systems to illustrate approaches to assessing the extent of complexity. The paper applies Appreciative Inquiry to identify and assess complex system characteristics. The characteristics are used to examine several different examples of systems to illuminate areas of complexity. These examples range from seemingly simple systems to complicated systems to complex systems. Different tiers of complexity are identified as a result of the assessment. The paper also identified and introduces topics on managing complexity and the integrating system perspective that represent new directions for the engineering of complex systems. The Appreciative Inquiry approach provides a method for systems engineering practitioners to more readily identify complexity when they encounter it, and to deal more effectively with this complexity once it has been identified.
Eliciting Human Values by Applying Design Thinking Techniques in Systems Engineering
Authors: Sjøkvist Nina Marie , Kjørstad Marianne
Published: September 2019

The objective of this study is to investigate the effect of Design Thinking techniques for capturing and communicating human values in the early phase of Systems Engineering. To develop products, systems, or services that satisfy the stakeholders, the systems engineer (SE) must understand the emotional needs of the stakeholder. The goal is to derive stakeholder requirements from the need analysis to create solutions that satisfy the quantitative and emotional need of the stakeholders. A development project team conducts three field visits where they interview and observe stakeholders in their work environment. The project team uses visual mapping tools to communicate and discuss findings and to create a mutual understanding of the stakeholder needs. We evaluate the method using interviews, surveys, and analyses of the derived requirements. The results indicate that the team gained a better understanding of the human values and succeeded in deriving human values into stakeholder requirements.
Famous Failures Revisited: A Focus on System Integration
Authors: Armstrong James R
Published: September 2019

A prior INCOSE paper addressed several famous failures from the viewpoint of the impact of requirements, verification, and validation. That paper has been used for pre‐reading material and initial class discussion in a course on system integration that also includes verification and validation. The discussion also notes that the original paper does not address the impact of integration on these failures. This paper adds that viewpoint and includes several other instances to develop several aspects that should be considered in systems integration.
INCOSE SE Handbook V4 to CMMI V2.0 Development Mapping
Authors: Mondragon Oscar A. , Jasso Rene
Published: September 2019

This paper addresses the need for a detailed mapping between INCOSE SE Handbook V4 (Handbook) and CMMI V2.0 Development (CMMI‐DEV). CMMI‐DEV was released in March 2018. The Handbook and CMMI‐DEV are good references for Systems Engineering practitioners. Learning both of them enhances practitioner knowledge and provides complementary points of view for similar Systems Engineering concepts. This paper includes both high‐level mapping, depicting the structure of Handbook and CMMI‐DEV, and detailed mapping, depicting for each process activity in the Handbook all associated CMMI‐DEV practices. Moreover, the detailed mapping provides percentage of coverage for each activity and its entire process. The paper addresses the target audience; the methodology followed to create both levels of the mappings; amount of commonality between Handbook process activities and the CMMI‐DEV practices; percentage of coverage analysis at the process and process group level in the Handbook; and overall results.
A Model‐Based V&V Test Strategy Based on Emerging System Modeling Techniques
Authors: Wang Gan , Pavalkis Saulius
Published: September 2019

This paper describes a two‐stage, model‐based system testing approach to manage engineering changes on the established design baseline in the SysML based system model environment by leveraging standard‐based model execution and simulation. The technical baseline established in SysML is extended to PLM and the test domain through RFLP‐T architecture traceability. Using a real project Virtual Factory™, this paper demonstrates the application of model‐based testing to the early verification and validation (V&V) of system requirements and functionalities and to developing integrated system testing by reusing and expanding the test cases to interface with external, manual‐based test procedures during the final system test phase.
Towards a Model‐Based approach to Systems and Cyber Security co‐engineering
Authors: Navas Juan , Voirin Jean-Luc , Paul Stephane , Bonnet Stephane
Published: September 2019

As cybersecurity threats multiply and global public opinion becomes aware of the potential consequences of cybersecurity attacks, customers become more demanding with regard to the proper addressing of cybersecurity concerns in the systems they acquire. As a consequence, systems providers should consider such concerns early in the development life‐cycle of their solutions. This paper presents how a model‐based approach can contribute to an effective co‐engineering effort between cybersecurity and systems engineering during the definition of the system architecture.
Transitioning from technical 2D drawings to 3D models: a case study at defense systems
Authors: Sandberg Martin , Kokkula Satyanarayana , Muller Gerrit
Published: September 2019

Companies in the defense and aerospace industry are experiencing long time‐to‐market and high costs related to the development of new systems. Companies use traditional design elements such as technical 2D drawings and manual work along the development chain. Owing to today's software capabilities, a change to more automated processes is possible, where the use of 3D models as governing documents through the entire development process holds a natural part.

This paper studies a 3D model‐based definition (MBD) approach to the design development work at Kongsberg Defence & Aerospace. Using a pilot project, we researched the current design processes and the effect an MBD approach would have. We found that an MBD approach would reduce the time‐to‐market and cost, since it eliminates the need for a technical 2D drawing and streamlines the development work. In addition, it reduces project risk by enabling early validation of the design.
Systems Theoretic Process Analysis for Layers of System Safety
Authors: Hegde Rashmi , Yako Sarra , Post Kyle , Nuesch Sandro
Published: September 2019

The move toward autonomous vehicles (AV) and mobility services extends the scope of traditional vehicle systems to include a much broader system definition. Questions often arise on how to identify a practical level of system hierarchy for the analysis. System Theoretic Process Analysis (STPA) is a hazard analysis technique that can be used to handle emergent properties of large, organized systems. However, STPA lacks the degree of formalization required to implement it successfully in a fast‐paced industrial environment. This paper introduces a framework to apply top‐down STPA on complex systems at multiple levels of decomposition and abstraction. In particular, we leverage the hierarchy within the system of interest (SOI) in tandem with STPA and proactively analyze complex dynamic processes that could potentially lead to accidents. This leads to multi‐level hierarchical progression of STPA on SOIs, in addition to analyzing each system element at different abstraction levels. The outcome of the analysis is a set of requirements for safety, cybersecurity, performance and business needs. The paper also provides guidelines on using these derived requirements to steer the system design. We demonstrate the efficacy of the proposed methodology by applying it to an AV ride‐sharing ecosystem.
The challenges in implementing future interoperable joint C4ISR systems
Authors: OZTURK Ali , DURMUS Suna , UZUMCU Serdar
Published: September 2019

The unprecedented scale of ultra large scale (ULS) systems spans into various dimensions like lines of code, amount of information processed, number of interdependent hardware and computational components, number of people involved etc. The characteristics of ULS systems due to their scale pose different challenges which could only be addressed by a multi‐disciplinary research rather than the traditional software engineering approaches. In this paper, we focused on proposing solutions against challenges in implementing the future interoperable joint Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) systems. For this purpose, we examined the main research topics to address the challenges in ULS systems. We discussed two main capabilities to enable the vision of future interoperable joint C4ISR. One of these capabilities is the effective and secure use of information across components of the system, while the other one is real‐time fusion of the available information with the local context.
Upregulation of FSHR and PCNA by administration of coenzyme Q10 on cyclophosphamide‐induced premature ovarian failure in a mouse model
Authors: Delkhosh Aref , Delashoub Masoud , Tehrani Ali Asghar , Bahrami Ali Mohammad , Niazi Vahid , Shoorei Hamed , Banimohammad Majid , Kalarestaghi Hossein , Shokoohi Majid , Agabalazadeh Amin , Mohaqiq Mahdi
Published: September 2019

Cyclophosphamide (CTX) has been broadly used in the clinic for the treatment of autoimmune disorders and ovarian cancer. The process of chemotherapy has significant toxicity in the reproductive system as it has detrimental effects on folliculogenesis, which leads to an irreversible premature ovarian failure (POF). Coenzyme Q10 (CoQ10) has positive impacts on the reproductive system due to its antioxidant properties, protecting the cells from free‐radical oxidative damage and apoptosis. However, little is known about the possible synergistic effect of CTX and CoQ10 on the expression of genes involved in folliculogenesis, such as proliferation cell nuclear antigen (PCNA) and follicle‐stimulating hormone receptor (FSHR). A total of 32 NMRI mice were applied and divided into four groups, including healthy control, CTX, CTX + CoQ10, and CoQ10 groups. The effects of CoQ10 on CTX‐induced ovarian injury and folliculogenesis were examined by histopathological and real‐time quantitative reverse transcription‐polymerase chain reaction analyses. The rates of fertilization (in vitro fertilization), embryo development, as well as the level of reactive oxygen species (ROS) in metaphase II (MII) mouse oocytes after PMSG/HCC treatment were also assessed. Results showed that the treatment with CTX decreased the mRNA expression of PCNA and FSHR, IVF rate, and embryo development whereas the application of CoQ10 successfully reversed those factors. CoQ10 administration significantly enhanced histological morphology and decreased ROS levels and the number of atretic follicles in the ovary of CTX‐treated mice. In conclusion, it seems that the protective effect of CoQ10 is exerted via the antioxidant and proliferative properties of this substance on CTX‐induced ovarian damage.
Excess postexercise oxygen consumption decreases with swimming duration in a labriform fish: Integrating aerobic and anaerobic metabolism across time
Authors: Cordero Gerardo A. , Methling Caroline , Tirsgaard Bjørn , Steffensen John F. , Domenici Paolo , Svendsen Jon C.
Published: September 2019

Many vertebrate animals employ anaerobic pathways during high‐speed exercise, even if it imposes an energetic cost during postexercise recovery, expressed as excess postexercise oxygen consumption (EPOC). In ectotherms such a fish, the initial anaerobic contribution to exercise is often substantial. Even so, fish may recover from anaerobic pathways as swimming exercise ensues and aerobic metabolism stabilizes, thus total energetic costs of exercise could depend on swimming duration and subsequent physiological recovery. To test this hypothesis, we examined EPOC in striped surfperch (Embiotoca lateralis) that swam at high speeds (3.25 L s−1) during randomly ordered 2‐, 5‐, 10‐, and 20‐min exercise periods. We found that EPOC was highest after the 2‐min period (20.9 mg O2 kg−1) and lowest after the 20‐min period (13.6 mg O2 kg−1), indicating that recovery from anaerobic pathways improved with exercise duration. Remarkably, EPOC for the 2‐min period accounted for 72% of the total O2 consumption, whereas EPOC for the 20‐min period only accounted for 14%. Thus, the data revealed a striking decline in the total cost of transport from 0.772 to 0.226 mg O2·kg−1·m−1 during 2‐ and 20‐min periods, respectively. Our study is the first to combine anaerobic and aerobic swimming costs to demonstrate an effect of swimming duration on EPOC in fish. Clarifying the dynamic nature of exercise‐related costs is relevant to extrapolating laboratory findings to animals in the wild.
Posterior Pelvic Tilt From Supine to Standing in Patients With Symptomatic Developmental Dysplasia of the Hip
Authors: Tani Tetsuro , Takao Masaki , Uemura Keisuke , Otake Yoshito , Hamada Hidetoshi , Ando Wataru , Sato Yoshinobu , Sugano Nobuhiko
Published: September 2019

Pelvic sagittal inclination (PSI) significantly affects the femoral head coverage by the acetabulum in patients with developmental dysplasia of the hip (DDH), while no reports have quantified PSI in DDH patients in the supine and standing positions. Furthermore, little is known about how PSI changes after periacetabular osteotomies. Herein, PSI in the supine and standing positions was quantified in DDH patients preoperatively and postoperatively. Twenty‐five patients with DDH who had undergone periacetabular osteotomies were analyzed. The preoperative PSI and the PSI 2 years after surgery were measured in the supine and standing positions using the image registration technique between radiographs and computed tomographic images. The percentage of patients who showed PSI changes of more than 10° from the supine to the standing position was quantified. PSI changed 8.2 ± 5.0° posteriorly from the supine to the standing position during the preoperative period. Posterior pelvic tilt of more than 10° was found in nine cases (36%). Two years after periacetabular osteotomies, the postural PSI change was 7.1 ± 3.9° posteriorly. When the preoperative and postoperative PSI values were compared, PSI in the standing position did not differ (p = 0.20). Similarly, the amount of PSI change from the supine to standing position was not significantly different (p = 0.26). In conclusion, posterior pelvic tilt in the standing position was found preoperatively in symptomatic DDH patients, and it remained for 2 years after periacetabular osteotomies. This postural change in PSI does not seem to influence the outcome of periacetabular osteotomy. However, during preoperative planning, surgeons should recognize that acetabular anteversion or anterior acetabular coverage differs between the supine and standing positions in some patients with DDH. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:578–587, 2020
Determination of vitamin A in blood serum based on solid‐phase extraction using cetyltrimethyl ammonium bromide‐modified attapulgite
Authors: Xuan Rongrong , Wang Tingting , Hou Chunyan , Li Xie , Li Ying , Chen Yihui , Gao Yajie , Qiu Dan , Xiao Xunwen , Zhang Lihua , Zhang Yukui
Published: September 2019

Cetyltrimethyl ammonium bromide‐modified attapulgite was prepared and utilized as a novel sorbent in a simple solid‐phase extraction method for the determination of vitamin A in blood serum. Several factors affecting extraction efficiency were systematically optimized, including the sampling solvent and its volume, as well as the elution solvent and its volume. Under the optimal solid‐phase extraction conditions, the adsorption capacity of vitamin A was as high as 28 mg/g according to the Langmuir isotherm model. Based on the developed solid‐phase extraction method, the level of vitamin A in 200 µL blood serum sample could be accurately determined by high‐performance liquid chromatography. The recoveries of vitamin A spiked in 10% v/v methanol aqueous solutions were in the range of 86.9–92.8%, with the relative standard deviations not more than 8.1%. The method was applied to the determination of vitamin A in serum samples from 20 pregnant women. Compared with the previously reported solid‐phase extraction methods for determination of vitamin A in serum, our developed cetyltrimethyl ammonium bromide‐modified attapulgite‐based solid‐phase extraction method used lower serum volume, omitted extra steps (i.e. evaporation and re‐dissolution), and eliminated internal standard. The results were promising for it to be used in routine monitoring during pregnancy.
Association between APOE polymorphisms and lipid profile in Mexican Amerindian population
Authors: Martínez‐Magaña José J. , Genis‐Mendoza Alma D. , Tovilla‐Zarate Carlos A. , González‐Castro Thelma B. , Juárez-Rojop Isela Esther , Hernández‐Díaz Yazmín , Martinez‐Hernandez Angélica G. , Garcia‐Ortíz Humberto , Orozco Lorena , López‐Narvaez María L. , Nicolini Humberto
Published: September 2019

Background

Apolipoprotein E (ApoE) is a glycoprotein that plays an important role in lipid homeostasis at both cerebral and systemic levels. Moreover, the differential distribution of APOE gene alleles among different populations, means that ApoE isoforms could have different effects on lipids metabolism. The present study aims to evaluate the relationship between APOE gene alleles and the lipid profile in a Mexican Amerindian (MA) population.

Methods

This study included 1997 MA individuals of different ethnicities distributed throughout different states of Mexico. All individuals underwent anthropometric measurements as well as laboratory tests including fasting glucose (FG), total cholesterol (TC), triglycerides, low‐density lipoprotein cholesterol (LDL‐C), and high‐density lipoprotein cholesterol (HDL‐C). TaqMan® probe genotyping assays were used to genotype APOE. The Kruskal–Wallis test was performed to determine the correlation between APOE gene alleles and genotypes and the biochemical variables measured.

Results

Among the biochemical variables analyzed, only the HDL‐C and LDL‐C levels showed statistical differences (p‐value < .05) between individuals carrying different APOE alleles. For HDL‐C, individuals carrying the E2 allele had higher HDL‐C levels, followed by individuals carrying the E3 allele and carriers of the E4 allele presented the lowest levels of HDL‐C (E2 > E3 > E4). This relationship was inversed for LDL‐C levels (E2 < E3 < E4). Nevertheless, the difference of HDL‐C levels between APOE‐E3 and APOE‐E4 carriers remained only in obese individuals.

Conclusions

Our results suggest that APOE gene genotypes play an important role in the differential modulation of lipid profiles in the MA population with obesity.
Taking HDR Cinema Mainstream
Authors: Ballestad Anders , Boitard Ronan , Damberg Gerwin , Stojmenovik Goran
Published: September 2019

Cinematic display solutions still lag behind consumer display technologies in terms of brightness and contrast, but new improvements could help them catch up. In this article, the second of a two‐part series, we explore challenges that must be addressed and potential solutions that could be incorporated to enable a mainstream rollout of HDR in cinema.
Display Metrology: The “Informed Conscience” of the Industry
Authors: Fiske Tom
Published: September 2019

Metrology and its application to displays were well represented at Display Week, in symposium sessions, standards meetings, and on the exhibit floor. Here are some of the most important takeaways.