bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement of Enzymatic Hydrolysis of Lignocellulose by Tetrabutylammonium Hydroxide (TBAOH) and Tetramethylammonium Hydroxide (TMAOH) Aqueous Solution Pretreatment
Authors: Zhang Qiao‐Zhi , Ding Ran , Sun Jian‐Fei , Li Xin , Luo Wen‐Ting , Yin Jian‐Zhong 
Published: January 2021

AbstractBACKGROUNDLignocellulose is usually pretreated as a raw material, and then it undergoes hydrolysis, fermentation, and other processes to produce biofuels, which is conducive to improving the utilization of agricultural and forestry wastes. However, most pretreatments, such as acid–base, CO2 explosion, and microbial degradation, could enhance the yield of enzymatically hydrolyzed (EH) sugars, but the conditions are relatively harsh, environmentally unfriendly, and economically unfeasible. Ionic liquids, in view of their excellent physical and chemical properties and strong solubility, have been proven to be an effective green solvent for pretreating lignocellulose. The aim of this study was to exploit tetrabutylammonium hydroxide (TBAOH) and tetramethylammonium hydroxide (TMAOH) aqueous solutions to pretreat corn cob under relatively mild conditions.RESULTSThe optimal pretreatment conditions for the two solutions were 30 °C, TBAOH concentration of 20 wt%, 60 min, 5 wt/wt, and 20 °C, TMAOH concentration of 10 wt%, 60 min, 5 wt/wt, and the corresponding sugar yields were 88.9% and 92.2%, respectively. Compared with the unpretreated corn cob, the yield of EH sugar increased by about 2.7–2.8 times. Characterization results confirmed that hemicelluloses and lignin were removed from the raw material during the pretreatment process, and that the cellulose was purified. Furthermore, after 5 cycles of reuse of the TBAOH and TMAOH aqueous solutions, the pretreated corn cob could still achieve a sugar yield higher than 70%.CONCLUSIONThe pretreatment with TBAOH and TMAOH aqueous solutions significantly enhanced the enzymatic hydrolysis, which provided a green, simple, and economical new approach for the pretreatment of agricultural waste biomass. © 2021 Society of Chemical Industry
CPO‐Fe3O4@mTiO2 nanocomposite with integrated magnetic separation and enzymatic and photocatalytic activities in efficient degradation of organic contaminants in wastewater
Authors: Wang Xun , Cheng Hanping , Gao Fengqin , Wang Jing , Zhai Quanguo , Hu Mancheng , Li Shuni , Jiang Yucheng 
Published: January 2021

AbstractBACKGROUNDImmobilization of enzymes on a nanocarrier can improve their stability, but is often accompanied by a reduction of the initial catalytic activity. Meanwhile, inevitable mass loss during centrifugal separation inhibits reusability. It is still a challenge to design and prepare an immobilized enzyme with both improved catalytic activity and reusability simultaneously.RESULTSCore–shell magnetic microspheres (Fe3O4@mTiO2) with mesoporous structure were prepared and used to construct an enzymatic nanocomposite (CPO‐Fe3O4@mTiO2). This material can combine magnetic separability, photocatalytic property of TiO2 and enzymatic activity of chloroperoxidase (CPO) when applied in the degradation of aqueous organic contaminants diphenylamine and pesticide residue isoproturon. Moreover, CPO‐Fe3O4@mTiO2 showed good stability and reusability. It can keep 78.0% and 66.8% of its initial activity after incubation at 80 and 90 °C for 1 h, respectively, while free CPO only retained 18.3% and 6.9% of its original activity for the same conditions. After being used for eight cycles, CPO‐Fe3O4@mTiO2 can retain over 82.2% of activity. When applied in the degradation of isoproturon/diphenylamine in artificial wastewater, 60 μmol L−1 isoproturon can be completely degraded in 30 min; 82.2% of diphenylamine can be degraded at a concentration of 10 μmol L−1. Compared with the removal of aqueous contaminants using a porous adsorbent, CPO‐Fe3O4@mTiO2 can be regenerated ‘online’, obviating complicated procedures for regeneration.CONCLUSIONSThe results indicate that CPO‐Fe3O4@mTiO2 has potential for practical application in the treatment of wastewater. © 2021 Society of Chemical Industry
1H‐NMR analysis, antioxidant activity, and α‐amylase and α‐glucosidase inhibitory potential of ten common Thai edible flowers
Authors: Wongsa Prinya , Rattanapanone Nithiya 
Published: January 2021

AbstractBACKGROUNDEdible flowers have been used in cooking as foods as well as medicine alternatives. The objectives were to identify a major class of organic compounds in edible flowers by applying proton nuclear magnetic resonance (1H‐NMR) metabolite fingerprinting and to evaluate bioactivity including antioxidant and α‐amylase and α‐glucosidase inhibitory activities.RESULTSA total of 32 metabolites including five organic acids, eight sugars, 11 amino acids and eight phenolic compounds were identified by using 1H‐NMR at 600 MHz. The aromatic proton of phenolic compounds was observed at the low‐field region ranged between δ 5.5 ppm and 10.0 ppm. Total phenolic content (TPC) of the extracts of edible flowers ranged from 6.0 mg GAE g−1 dry weight (DW) to 47.97 mg GAE g−1 DW. Antioxidant activity varied from 140.5 mmol L−1 TE g−1 DW to 985.2 mmol L−1 TE g−1 DW. The extracts from edible flowers showed dose‐dependent inhibition against enzyme. The extract of African marigold (Tagetes erecta L.) had the highest half maximal inhibitory concentration (IC50) against α‐amylase at 0.13 mg mL−1 while the extract of flower of Sesban agasta (Sesbania grandiflora Desv.) had the lowest IC50 against α‐amylase at 0.63 mg mL−1. Moderate correlation was found between IC50 values against α‐glucosidase and antioxidant activity values (R2 = 0.66) (P < 0.05).CONCLUSION1H‐NMR application provided metabolomic fingerprinting of edible flowers and the in vitro inhibitory potential activity against key enzymes related to diabetes indicated that specific edible flowers have a potential use for dietary management during the early stages of hyperglycaemia. © 2021 Society of Chemical Industry
Challenges in Certifying Small-Scale (IoT) Hardware Random Number Generators
Authors: Hurley-Smith Darren , Hernandez-Castro Julio 
Published: January 2021

AbstractThis chapter focuses on the testing and certification of Random Number Generators (RNG). Statistical testing is required to identify whether sequences produced by RNG demonstrate non-random characteristics. These can include structures within their output, repetition of sequences, and any other form of predictability. Certification of computer security systems draws on such evaluations to determine whether a given RNG implementation contributes to a secure, robust security system. Recently, small-scale hardware RNGs have been targeted at IoT devices, especially those requiring security. This, however, introduces new technical challenges; low computational resources for post-processing and evaluation of on-board RNGs being just two examples. Can we rely on the current suite of statistical tests? What other challenges are encountered when evaluating RNG?
Finding Software Bugs in Embedded Devices
Authors: Francillon Aurélien , Thomas Sam L. , Costin Andrei 
Published: January 2021

AbstractThe goal of this chapter is to introduce the reader to the domain of bug discovery in embedded systems which are at the core of the Internet of Things. Embedded software has a number of particularities which makes it slightly different to general purpose software. In particular, embedded devices are more exposed to software attacks but have lower defense levels and are often left unattended. At the same time, analyzing their security is more difficult because they are very “opaque”, while the execution of custom and embedded software is often entangled with the hardware and peripherals. These differences have an impact on our ability to find software bugs in such systems. This chapter discusses how software vulnerabilities can be identified, at different stages of the software life-cycle, for example during development, during integration of the different components, during testing, during the deployment of the device, or in the field by third parties.
An Account of the ISO/IEC Standardization of the Simon and Speck Block Cipher Families
Authors: Ashur Tomer , Luykx Atul 
Published: January 2021

AbstractSimon and Speck are two block cipher families published in 2013 by the US National Security Agency (NSA). These block ciphers, targeting lightweight applications, were suggested in 2015 to be included in ISO/IEC 29192-2 Information technology—Security techniques—Lightweight cryptography—Part 2: Block ciphers. Following 3.5 years of deliberations within ISO/IEC JTC 1 they were rejected in April 2018. This chapter provides an account of the ISO/IEC standardization process for Simon and Speck.
Ultra-lightweight Authentication
Authors: Carpent Xavier , D’Arco Paolo , Prisco Roberto De 
Published: January 2021

AbstractIn this chapter we provide acritical lookat the state of the art in ultra-lightweight authentication protocols. We start by outlining the features of the current ubiquitous and pervasive computing environment that have motivated the development of the ultra-lightweight paradigm which uses only basic arithmetic and logical operations. We emphasize its goals and its main challenges. Then, we focus our attention on the authentication problem. We use an abstract framework for modeling the protocols proposed over the years, in order to discuss their design strategies and the security and privacy properties they aim to achieve. After that, we survey the weaknesses and the common pitfalls in both the design and the analysis of ultra-lightweight authentication protocols. Finally, we conclude the chapter by discussing some fundamental ideas and research directions.
Side Channel Assessment Platforms and Tools for Ubiquitous Systems
Authors: Fournaris Apostolos P. , Moschos Athanassios , Sklavos Nicolas 
Published: January 2021

AbstractSide Channel Attacks are nowadays considered a serious risk for many security products and ubiquitous devices. Strong security solution providers need to evaluate their implementations against such attacks before publishing them on the market, thus performing a thorough assessment. However, this procedure is not straightforward and even with the appropriate equipment, it may require considerable time to provide results due to the slow process of collecting measurements (traces) and the inflexible way of controlling the tested implementation. In this chapter, we explore and overview the trace collection landscape for generic devices under test (including ubiquitous systems) highlighting and overviewing the latest trace collection toolsets and their shortcomings, but also proposing a trace collection approach that can be applied on the most recent, open source toolsets. We showcase our proposed approach on the FlexLeco project architecture, which we have developed in our lab, and manage to practically describe how an evaluator using the proposed methodology can collect traces easily and quickly without the need to completely redesign a control mechanism for the implementation under test.
Lateral Network Governance
Authors: Glückler Johannes 
Published: January 2021

AbstractThe author of this article goes beyond acknowledging networks as a governance mode to elaborate on the actual forms of governance that convey legitimate and acceptable coordination. He advances the concept of lateral network governance in the empirical context of organized networks, in which organizations pool resources and join their interests in the pursuit of common goals. To solve the puzzle of having independent equals commit themselves to coordinating their actions, the author aims to overcome the traditional dualism between formal and informal mechanisms of governance. Instead, he conceives lateral network governance as a structure for the legitimate delegation of decision-making. He develops a social network analytic approach to assessing the relational distribution of legitimacy. With his empirical analysis of two case studies of inter-firm network organizations, he illustrates the degree to which the actual legitimacy distribution diverges from formal governance authority. Lateral network governance has practical implications for inter-organizational networks and network managers.
Nurturing Adaptive Governance Through Environmental Monitoring: People, Practices, Politics in the Kruger to Canyons Biosphere Region, South Africa
Authors: Schultz Lisen , West Simon , Florêncio Cláudia 
Published: January 2021

AbstractAdaptive governance is an approach that can potentially help societies navigate uncertainty, change, and surprise, as well as issues that span sectors and scales. In this chapter, we use this concept to refer to flexible and learning-based collaborations and decision-making processes involving both state and non-state actors, with the aim to adaptively negotiate and coordinate management of social-ecological issues. We identify critical questions in the adaptive governance literature and provide an empirical contribution to these. We draw on a case study of the Kruger to Canyons Biosphere Region in South Africa, focusing on the people, practices, and politics involved with adaptive governance in the Global South. Our findings illustrate that the practices of generating knowledge, sharing information, collaborating, and responding to change are shaped by the navigation of tensions between diverse values, norms, and routines. A lens of people, practices, and politics highlights adaptive governance as situated and involving agency, meaning, and creativity.
Let’s Join: A Pavilion Inspired by the Weaire and Phelan Space Tessellation
Authors: Valenti Graziano Mario , El Khoury Chadi 
Published: January 2021

AbstractThe pavilion presented in this paper is an articulation of space based on the Weaire and Phelan tessellation. In this pavilion a second generative pattern is partially engraved and cut out of the polygonal surfaces that bind the polyhedron. This pattern is made up of cubic curves that aim to spatially engage with the tessellation. The design and prototyping process was implemented and controlled using parametric and procedural models. The use of these models made it possible to define the shape, orientation, and size of each element of the pavilion: from the polyhedron and the pattern’s curves, to smaller components like the shape of the panels’ joints, holes, and the countersinks that hold the screws. This research illustrates the geometric, formal, and procedural design that was used to shape the pavilion in its current spatial configuration, to draw the pattern cut and engraved into the polyhedron’s surface, and finally, to determine the shape and scale of the joints that hold the faces of the polyhedron together and characterize the internal space. Regarding the topic ofPatterns and Spatial Organization, the paper investigates shape design methodologies, which are based on historical practices but updated using new technologies.
The pure cohomology of multiplicative quiver varieties
Authors: McGerty Kevin , Nevins Thomas 
Published: January 2021

AbstractTo a quiver Q and choices of nonzero scalars $$q_i$$

q
i

, non-negative integers $$\alpha _i$$

α
i

, and integers $$\theta _i$$

θ
i

labeling each vertex i, Crawley-Boevey–Shaw associate a multiplicative quiver variety$${\mathcal {M}}_\theta ^q(\alpha )$$

M
θ
q

(
α
)

, a trigonometric analogue of the Nakajima quiver variety associated to Q, $$\alpha $$
α
, and $$\theta $$
θ
. We prove that the pure cohomology, in the Hodge-theoretic sense, of the stable locus $${\mathcal {M}}_\theta ^q(\alpha )^{{\text {s}}}$$

M
θ
q

(
α
)

s

is generated as a $${\mathbb {Q}}$$
Q
-algebra by the tautological characteristic classes. In particular, the pure cohomology of genus g twisted character varieties of $$GL_n$$

G

L
n

is generated by tautological classes.
Functional and directed connectivity of the cortico-limbic network in mice in vivo
Authors: Khastkhodaei Zeinab , Muthuraman Muthuraman , Yang Jenq-Wei , Groppa Sergiu , Luhmann Heiko J. 
Published: January 2021

AbstractHigher cognitive processes and emotional regulation depend on densely interconnected telencephalic and limbic areas. Central structures of this cortico-limbic network are ventral hippocampus (vHC), medial prefrontal cortex (PFC), basolateral amygdala (BLA) and nucleus accumbens (NAC). Human and animal studies have revealed both anatomical and functional alterations in specific connections of this network in several psychiatric disorders. However, it is often not clear whether functional alterations within these densely interconnected brain areas are caused by modifications in the direct pathways, or alternatively through indirect interactions. We performed multi-site extracellular recordings of spontaneous activity in three different brain regions to study the functional connectivity in the BLA–NAC–PFC–vHC network of the lightly anesthetized mouse in vivo. We show that BLA, NAC, PFC and vHC are functionally connected in distinct frequency bands and determined the influence of a third brain region on this connectivity. In addition to describing mutual synchronicity, we determined the strength of functional connectivity for each region in the BLA–NAC–PFC–vHC network. We find a region-specificity in the strength of feedforward and feedback connections for each region in its interaction with other areas in the network. Our results provide insights into functional and directed connectivity in the cortico-limbic network of adult wild-type mice, which may be helpful to further elucidate the pathophysiological changes of this network in psychiatric disorders and to develop target-specific therapeutic interventions.
Investigation of the Influence of Powder Moisture on the Spreadability Using the Spreading Tester
Authors: Mitterlehner Marco , Danninger Herbert , Gierl-Mayer Christian , Gschiel Harald 
Published: January 2021

AbstractMoisture is often regarded as one of the main reasons for poor processability of powders using Laser-powder bed fusion (L-PBF) processes. To determine the influence of moisture on the spreadability, a superalloy powder IN718 commonly used for L‑PBF processes has been conditioned in two different states: once in the as-received and dry condition and once in a moist condition obtained by storing the powder for four weeks in an atmosphere containing a relative humidity of 75%. Using a self-built spreading tester and a subsequent analysis method specially developed for testing the spreadability of a powder, the differently conditioned IN718 powder batches have been investigated regarding the surface roughness and flatness of the powder layers. Additionally, the formation of empty spots between the powder particles in the top layer has been studied.
Spreadability Testing of Powder for Additive Manufacturing
Authors: Hulme-Smith Christopher Neil , Hari Vignesh , Mellin Pelle 
Published: January 2021

AbstractThe spreading of powders into thin layers is a critical step in powder bed additive manufacturing, but there is no accepted technique to test it. There is not even a metric that can be used to describe spreading behaviour. A robust, image-based measurement procedure has been developed and can be implemented at modest cost and with minimal training. The analysis is automated to derive quantitative information about the characteristics of the spread layer. The technique has been demonstrated for three powders to quantify their spreading behaviour as a function of layer thickness and spreading speed.
Vertikale Blickparesen bei dorsalem Mittelhirnsyndrom und anderen Erkrankungen
Authors: Pemp Berthold , Koinig Sabine , Kircher Karl , Mitsch Christoph , Reitner Andreas 
Published: January 2021

Zusammenfassung
Hintergrund
Die vertikale Blickparese (vBP) ist ein typisches Symptom bei Läsionen des dorsalen Mittelhirns. Die klinische Ausprägung der vBP kann dabei stark variieren und im Rahmen eines dorsalen Mittelhirnsyndroms (DMS) mit zusätzlichen Symptomen wie einer Konvergenzparese, einem Konvergenzretraktionsnystagmus, einer verminderten Pupillenreaktion oder einer Skew Deviation vergesellschaftet sein. Je nach Lokalisation und Größe der Läsion kann auch eine Kombination mit weiteren zentralen Motilitätsstörungen vorliegen.

Material und Methode
Im Rahmen einer retrospektiven Studie wurden die Patientendaten unserer neuroophthalmologischen Ambulanz über einen Zeitraum von 25 Jahren nach Fällen mit Einschränkungen konjugierter vertikaler Augenbewegungen durchsucht und hinsichtlich ihrer neuroorthoptischen Befunde und Ätiologien ausgewertet.

Resultate
Es wurden 202 Patienten mit vBP identifiziert. Das Befundspektrum reichte von einer isolierten Sakkadenstörung nur nach oben bis hin zum kompletten Ausfall aller willkürlichen und reflektorischen vertikalen Augenbewegungen. Nur 12 vBP lagen isoliert vor. Ursächlich war bei 155 Patienten ein DMS, wovon aber nur 18 Fälle dem von Parinaud geprägten Syndrombild (vBP + Konvergenzparese ± Pupillenstörung ohne weitere Symptome) entsprachen; 42 Patienten mit DMS zeigten lediglich eine Sakkadenparese. Der Aufblick war bei DMS insgesamt mehr eingeschränkt als der Abblick. Die häufigsten Begleitsymptome waren eine Konvergenzparese (49 %), Konvergenznystagmus (40 %), Pupillenstörung (32 %), Skew Deviation (21 %) und Blickrichtungsnystagmus (15 %). In 58 Fällen traten weitere zentrale Okulomotorikstörungen auf. Bis zum 18. Lebensjahr war eine vBP bei 58 % der Patienten durch Gehirntumoren bedingt, wohingegen nach dem 60. Lebensjahr neben einem DMS durch Infarkte (41 %) v. a. degenerative Erkrankungen (44 %) ursächlich waren.

Schlussfolgerungen
Langsame und schnelle Augenbewegungen nach oben und unten werden im Hirnstamm unterschiedlich generiert, geleitet und integriert und können daher bei Läsionen des Mittelhirns verschieden stark gestört sein. Die Ergebnisse verdeutlichen zudem die enge Lagebeziehung der Zentren für vertikale Augenbewegungen, Konvergenz und Pupillenreaktion im dorsalen Mittelhirn. Die Kombination einer vBP mit weiteren neuroophthalmologischen Diagnosen kann daher eine topografische und ätiologische Zuordnung erleichtern.
Synkopenabklärung bei Kindern und Jugendlichen – Handeln wir gemäß der aktuellen Leitlinie?
Authors: Landwehr Katharina , Meyer Sascha , Flotats-Bastardas Marina , Poryo Martin 
Published: January 2021

Zusammenfassung
Hintergrund
Synkopen im Kindes‑/Jugendalter sind häufig und meist gutartig. Mögliche kardiale Synkopen müssen durch sorgfältige Basisdiagnostik (Anamnese (I), körperliche Untersuchung (II), Elektrokardiografie (III)) und ggf. weiterführender Diagnostik ausgeschlossen werden.

Fragestellung
Wurde die Diagnostik bei Vorliegen einer Synkope entsprechend der gültigen S2k-Leitlinie durchgeführt?

Material und Methoden
Retrospektive Analyse (01/2015–12/2017), Kinderklinik des Universitätsklinikums des Saarlandes, Homburg, Deutschland. Eingeschlossen wurden alle Patienten von 1 bis 18 Jahre, die sich wegen Synkope vorstellten.

Ergebnisse
Es erlitten 262 Patienten eine Synkope (161 weiblich [61,5 %], 101 männlich [38,5 %], Alter 12,5 ± 3,9 Jahre); davon 183 (69,8 %) Reflexsynkopen, 36 (13,7 %) Präsynkopen, 35 (13,4 %) Synkopen unklarer Genese, 8 (3,1 %) kardiale Synkopen; 43/262 Patienten (16,4 %) erhielten eine vollständiger Basisdiagnostik (I–III) gemäß Leitlinie, 13/43 (30,2 %) wurden korrekt weiterführender Diagnostik zugeführt; 219/262 Patienten (83,6 %) erhielten keine ausreichende Basisdiagnostik (I–III), 135/219 (61,6 %) wurden unnötigen apparativen Untersuchungen zugeführt.

Diskussion
Die leitlinienkonforme Synkopenabklärung ist wichtig, um unnötige, aber auch nicht ausreichende Diagnostik zu vermeiden und somit Patienten mit Synkope korrekt zu diagnostizieren.