| 1. |
- B. Brant Carvalho, Paulo H., et al.
(författare)
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Exploring High-Pressure Transformations in Low-Z (H2, Ne) Hydrates at Low Temperatures
- 2022
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Ingår i: Crystals. - : MDPI AG. - 2073-4352. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- The high pressure structural behavior of H-2 and Ne clathrate hydrates with approximate composition H-2/Ne center dot~4H(2)O and featuring cubic structure II (CS-II) was investigated by neutron powder diffraction using the deuterated analogues at ~95 K. CS-II hydrogen hydrate transforms gradually to isocompositional C-1 phase (filled ice II) at around 1.1 GPa but may be metastably retained up to 2.2 GPa. Above 3 GPa a gradual decomposition into C-2 phase (H-2 center dot H2O, filled ice I-c) and ice VIII' takes place. Upon heating to 200 K the CS-II to C-1 transition completes instantly whereas C-1 decomposition appears sluggish also at 200 K. C-1 was observed metastably up to 8 GPa. At 95 K C-1 and C-2 hydrogen hydrate can be retained below 1 GPa and yield ice II and ice I-c, respectively, upon complete release of pressure. In contrast, CS-II neon hydrate undergoes pressure-induced amorphization at 1.9 GPa, thus following the general trend for noble gas clathrate hydrates. Upon heating to 200 K amorphous Ne hydrate crystallizes as a mixture of previously unreported C-2 hydrate and ice VIII'.
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| 2. |
- B. Brant Carvalho, Paulo H., et al.
(författare)
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Pressure-induced amorphization of noble gas clathrate hydrates
- 2021
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Ingår i: Physical Review B. - : American Physical Society. - 2469-9950 .- 2469-9969. ; 103:6
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Tidskriftsartikel (refereegranskat)abstract
- The high-pressure structural behavior of the noble gas (Ng) clathrate hydrates Ar center dot 6.5 H2O and Xe center dot 7.2 H2O featuring cubic structures II and I, respectively, was investigated by neutron powder diffraction (using the deuterated analogues) at 95 K. Both hydrates undergo pressure-induced amorphization (PIA), indicated by the disappearance of Bragg diffraction peaks, but at rather different pressures, at 1.4 and above 4.0 GPa, respectively. Amorphous Ar hydrate can be recovered to ambient pressure when annealed at >1.5 GPa and 170 K and is thermally stable up to 120 K. In contrast, it was impossible to retain amorphous Xe hydrate at pressures below 3 GPa. Molecular dynamics (MD) simulations were used to obtain general insight into PIA of Ng hydrates, from Ne to Xe. Without a guest species, both cubic clathrate structures amorphize at 1.2 GPa, which is very similar to hexagonal ice. Filling of large-sized H cages does not provide stability toward amorphization for structure II, whereas filled small-sized dodecahedral D cages shift PIA successively to higher pressures with increasing size of the Ng guest. For structure I, filling of both kinds of cages, large-sized T and small-sized D, acts to stabilize in a cooperative fashion. Xe hydrate represents a special case. In MD, disordering of the guest hydration structure is already seen at around 2.5 GPa. However, the different coordination numbers of the two types of guests in the crystalline cage structure are preserved, and the state is shown to produce a Bragg diffraction pattern. The experimentally observed diffraction up to 4 GPa is attributed to this semicrystalline state.
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| 3. |
- B. Brant Carvalho, Paulo H., et al.
(författare)
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Structural investigation of three distinct amorphous forms of Ar hydrate
- 2021
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Ingår i: RSC Advances. - : Royal Society of Chemistry. - 2046-2069. ; 11:49, s. 30744-30754
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Tidskriftsartikel (refereegranskat)abstract
- Three amorphous forms of Ar hydrate were produced using the crystalline clathrate hydrate Ar·6.5H2O (structure II, Fd3m, a ≈ 17.1 Å) as a precursor and structurally characterized by a combination of isotope substitution (36Ar) neutron diffraction and molecular dynamics (MD) simulations. The first form followed from the pressure-induced amorphization of the precursor at 1.5 GPa at 95 K and the second from isobaric annealing at 2 GPa and subsequent cooling back to 95 K. In analogy to amorphous ice, these amorphs are termed high-density amorphous (HDA) and very-high-density amorphous (VHDA), respectively. The third amorph (recovered amorphous, RA) was obtained when recovering VHDA to ambient pressure (at 95 K). The three amorphs have distinctly different structures. In HDA the distinction of the original two crystallographically different Ar guests is maintained as differently dense Ar–water hydration structures, which expresses itself in a split first diffraction peak in the neutron structure factor function. Relaxation of the local water structure during annealing produces a homogeneous hydration environment around Ar, which is accompanied with a densification by about 3%. Upon pressure release the homogeneous amorphous structure undergoes expansion by about 21%. Both VHDA and RA can be considered frozen solutions of immiscible Ar and water in which in average 15 and 11 water molecules, respectively, coordinate Ar out to 4 Å. The local water structures of HDA and VHDA Ar hydrates show some analogy to those of the corresponding amorphous ices, featuring H2O molecules in 5- and 6-fold coordination with neighboring molecules. However, they are considerably less dense. Most similarity is seen between RA and low density amorphous ice (LDA), which both feature strictly 4-coordinated H2O networks. It is inferred that, depending on the kind of clathrate structure and occupancy of cages, amorphous states produced from clathrate hydrates display variable local water structures.
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| 4. |
- Baroni de Moraes, Marcia Terezinha, et al.
(författare)
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Phenotyping of Lewis and secretor HBGA from saliva and detection of new FUT2 gene SNPs from young children from the Amazon presenting acute gastroenteritis and respiratory infection
- 2019
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Ingår i: Infection, Genetics and Evolution. - : ELSEVIER SCIENCE BV. - 1567-1348 .- 1567-7257. ; 70, s. 61-66
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Tidskriftsartikel (refereegranskat)abstract
- The Histo-blood group antigens (HBGA) are host genetic factors associated with susceptibility to rotavirus (RV) and human norovirus (HuNoV), the major etiological agents of viral acute gastroenteritis (AGE) worldwide. The FUT2 gene expressing the alpha-1, 2-L- fucosyltransferase enzyme is important for gut HBGA expression, and also provides a composition of the phenotypic profile achieved through mutations occurring in populations with different evolutionary histories; as such, it can be considered a genetic population marker. In this study, Lewis and secretor HBGA phenotyping was performed using 352 saliva samples collected from children between three months and five years old born in the Amazon (Brazil, Venezuela and English Guyana) presenting AGE or acute respiratory infection (ARI), the latter considered as control samples. The total of children phenotyped as secretors was 323, corresponding to 91.80%. From these, 207 (58.80%) had a Le (a + b +) profile. The HBGA profiles were equally found in children with AGE as well as with ARI. The rs1047781 of the FUT2 gene was not detected in DNA from saliva cells with a Le (a + b +) profile. However, mutations not yet described in the FUT2 gene were observed: missense 325A amp;gt; T, 501C amp;gt; T, 585C amp;gt; T, 855A amp;gt; T and missense substitutions 327C amp;gt; T [S (Ser) amp;gt; C (Cys)], 446 T amp;gt; C [L(Leu) amp;gt; P(Pro)], 723C amp;gt; A [N(Asn) amp;gt; K(Lys)], 724A amp;gt; T [I(Ile) amp;gt; F(Phe)], 736C amp;gt; A [H(His) amp;gt; N(Asn)]. The SNP distribution in the FUT2 gene of the analyzed samples was very similar to that described in Asian populations, including indigenous tribes.
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| 5. |
- Bennulf, Mattias, 1992-
(författare)
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A Control Framework for Industrial Plug & Produce
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Kundanpassade produkter och korta produktionsserier blir alltmer populärt. Detta har lett till problem för dedikerade tillverkningssystem som är designade för massproduktion. Det krävs ofta långa produktionsserier för att det ska bli en rimlig investering att ställa om produktionen. Därför används människor för tillverkningsuppgifter som ofta ställs om. Denna avhandling fokuserar på konceptet Plug & Produce, som gör det enklare att flytta, lägga till och ta bort resurser från ett tillverkningssystem. Tanken är att resurser placeras i processmoduler som alla har samma fysiska gränssnitt för att kopplas in i tillverkningssystemet. Styrningen av tillverkningssystemet görs av ett multiagentsystem där varje detalj som ska produceras för produkter får en egen agent som representerar detaljen och agerar som styrningsmjukvara. Varje detaljs agent tar hand on sina egna tillverkningsmål genom att kommunicera med resursagenter i systemet som används för styrning av resurserna. I detta arbete, presenteras ett ramverk för Plug & Produce som består av ett konfigurerbart multiagentsystem, samt ett konfigurationsverktyg som kan användas för att definiera agenterna. Arbetet inkluderar metoder för att identifiera inkopplade resurser, kommunikation mellan agenter, schemaläggning som kan undvika konflikter mellan agenter, samt metoder för att automatiskt hitta vägar för transport genom tillverkningssystemet.
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| 6. |
- Colombo, Armando Walter, et al.
(författare)
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A 70-Year Industrial Electronics Society Evolution Through Industrial Revolutions : The Rise and Flourishing of Information and Communication Technologies
- 2021
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Ingår i: IEEE Industrial Electronics Magazine. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 1932-4529 .- 1941-0115. ; 15:1, s. 115-126
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Tidskriftsartikel (refereegranskat)abstract
- The Industrial Revolution, which originally involved the change from an agrarian and handicraft economy to a market dominated by factory mechanization during the early 18th century, has profoundly shaped the world. It has progressed through four disruptive phases: Industry 1.0 through Industry 4.0. Industry 1.0 encompassed early automation, while Industry 2.0 began at the end of the 19th century, when enormous technological advances were made, such as mass production, electrification, and new modes of transportation. Industry 3.0 began during the 1970s, a decade that gave rise to the electronics, telecommunications, and computing that enable full automation and robotics. Industry 4.0 kicked off at the dawn of the third millennium, marked by the ubiquitous use of Internet technologies, which have radically transformed how people, society, and industry interact.
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| 7. |
- Dai, Wenbin, et al.
(författare)
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Synergies of Operation, Information, and Communication Technology for Solving New Societal and Industrial Challenges : Future Directions
- 2024
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Ingår i: IEEE Industrial Electronics Magazine. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 1932-4529 .- 1941-0115.
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Tidskriftsartikel (refereegranskat)abstract
- The world is facing a series of new societal and industrial challenges, such as continuously increasing costs in food and energy supply and a short supply of skilled labor. To solve these new challenges, operation, information, and communication technology is entering a new era with more focus targeted to cost reduction and energy savings. In this article, how innovative technologies including virtualization, low-code development, digital twins, and industrial agents can support and impact digital and green transitions is analyzed. In addition, how these technologies will help the security and sustainability of future industrial automation systems is also discussed.
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| 8. |
- de Moraes, Marcia Terezinha Baroni, et al.
(författare)
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Molecular Epidemiology of Sapovirus in Children Living in the Northwest Amazon Region
- 2021
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Ingår i: Pathogens. - : MDPI. - 2076-0817. ; 10:8
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Tidskriftsartikel (refereegranskat)abstract
- Sapovirus is an important etiological agent of acute gastroenteritis (AGE), mainly in children under 5 years old living in lower-income communities. Eighteen identified sapovirus genotypes have been observed to infect humans. The aim of this study was to identify sapovirus genotypes circulating in the Amazon region. Twenty-eight samples were successfully genotyped using partial sequencing of the capsid gene. The genotypes identified were GI.1 (n = 3), GI.2 (n = 7), GII.1 (n = 1), GII.2 (n = 1), GII.3 (n = 5), GII.5 (n = 1), and GIV.1 (n = 10). The GIV genotype was the most detected genotype (35.7%, 10/28). The phylogenetic analysis identified sapovirus genotypes that had no similarity with other strains reported from Brazil, indicating that these genotypes may have entered the Amazon region via intense tourism in the Amazon rainforest. No association between histo-blood group antigen expression and sapovirus infection was observed.
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| 9. |
- Dias-Ferreira, João, 1986-
(författare)
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Bio-Inspired Self-Organising Architecture for Cyber-Physical Manufacturing Systems
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The refinement in consumer's requirements and the fast paced development of socio-technical systems, are promoting, increasingly globalized markets with a high demand for fast time-to-market, sustainable, high quality and highly customized, or even personalized, low priced products. This new reality is forcing companies to change and adapt their business strategies, so that they can quickly and efficiently engage in short-window business opportunities. A critical enabler of the companies' ability to tackle these opportunities is the shopfloor and its ability to cope with change. In this sense, a number of modern manufacturing paradigms emerged, that propose a relaxation of the strictness of the control chains and new modular system designs, that tolerate a controlled and regulated unpredictability of the system behaviour, and simultaneously foster the system's autonomy, robustness, adaptability, plug-ability, evolution and self-organisation.From a structural and dynamic perspective such solutions become, therefore, close to biological systems. In fact, biological systems and their characteristics are a common analogy to express the high level design principles, of modern production paradigms. However, despite this common source of inspiration, the application of bio-inspired concepts, is often lost due to design and implementation choices, or is simply limited to heuristic approaches, that solve specific hard optimization problems.In this dissertation, a bio-inspired reference architecture for production systems, focused on highly dynamic environments, denominated "BIO-inspired Self-Organising ARchitecture for Manufacturing systems" (BIOSOARM), is presented. BIOSOARM was developed under the umbrella of Evolvable Production Systems (EPS) and aims to strictly adhere to bio-inspired principles. For this purpose, both shopfloor components and product parts are individualized and extended into the virtual environment, as fully decoupled autonomous entities, where they interact, following bio-inspired patterns, and cooperate towards the emergence of a self-organising behaviour, that leads to the emergence of the necessary production flows and consequently of the desired products. BIOSOARM, therefore, introduces a fundamentally novel approach to production, that decouples the system's operation from eventual changes, uncertainty or even critical failures, while simultaneously ensures the performance levels and simplifies the deployment, reconfiguration/adaptation and evolution procedures, enabling companies to cope with the new highly dynamic and challenging environments.
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| 10. |
- Ferreira, Daniela, et al.
(författare)
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Transcription and regulation of the hydrogenase(s) accessory genes, hypFCDEAB, in the cyanobacterium Lyngbya majuscula CCAP 1446/4
- 2007
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Ingår i: Archives of Microbiology. - : Springer Science and Business Media LLC. - 0302-8933 .- 1432-072X. ; 188:6, s. 609-617
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Tidskriftsartikel (refereegranskat)abstract
- Lyngbya majuscula CCAP 1446/4 is a filamentous cyanobacterium possessing both an uptake and a bi-directional hydrogenase. The presence of a single copy of the hyp operon in the cyanobacterial genomes suggests that these accessory genes might be responsible for the maturation of both hydrogenases. We investigated the concomitant transcription of hypFCDEAB with the hydrogenases structural genes-hup and hox. RT-PCRs performed with L. majuscula cells grown under different physiological conditions showed a substantial decrease in the relative amount of hupL transcript under non-N-2-fixing conditions. In contrast, no significant differences were observed for the transcript levels of hypFCDEAB in all conditions tested, while minor fluctuations could be discerned for hoxH. Previously, it was demonstrated that the transcriptional regulators NtcA and LexA interact with the promoter regions of hup and hox, respectively, and that putative binding sites for both proteins are present in the hyp promoter of L. majuscula. Therefore, a putative involvement of NtcA and LexA in the regulation of the hyp transcription was investigated. Electrophoretic mobility shift assays resulted in NtcA or LexA-bound retarded fragments, suggesting the involvement of these proteins in the transcriptional regulation of hypFCDEAB.
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