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1
Losev, Ivan. "On Procesi bundles". Mathematische Annalen 359, n. 3-4 (9 febbraio 2014): 729–44. http://dx.doi.org/10.1007/s00208-014-1017-7.
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Ehrig, Michael, e Catharina Stroppel. "2-row Springer Fibres and Khovanov Diagram Algebras for Type D". Canadian Journal of Mathematics 68, n. 6 (1 dicembre 2016): 1285–333. http://dx.doi.org/10.4153/cjm-2015-051-4.
Testo completoAbstract (sommario):
AbstractWe study in detail two row Springer fibres of even orthogonal type from an algebraic as well as a topological point of view. We show that the irreducible components and their pairwise intersections are iterated ℙ1-bundles. Using results of Kumar and Procesi we compute the cohomology ring with its action of the Weyl group. The main tool is a type D diagram calculus labelling the irreducible components in a convenient way that relates to a diagrammatical algebra describing the category of perverse sheaves on isotropic Grassmannians based on work of Braden. The diagram calculus generalizes Khovanov's arc algebra to the type D setting and should be seen as setting the framework for generalizing well-known connections of these algebras in type A to other types.
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Carroll, Kathryn A., Anya Samek e Lydia Zepeda. "Consumer Preference for Food Bundles under Cognitive Load: A Grocery Shopping Experiment". Foods 11, n. 7 (27 marzo 2022): 973. http://dx.doi.org/10.3390/foods11070973.
Testo completoAbstract (sommario):
Product bundling is a common retail marketing strategy. The bundling of food items has the potential to increase profits in the grocery sector, particularly for fresh produce, which often has lower profit margins. Although prior work suggests consumers prefer bundles because they require less cognitive effort to select, no study has yet experimentally manipulated cognitive load when food bundles are included in the choice set. To test whether bundle preference differs when cognitive resources are constrained, a grocery shopping experiment was conducted with 250 consumers in the midwestern U.S., in a laboratory that featured a grocery store display. Consumers who grocery shopped under cognitive load had a higher odds of selecting a food bundle even when the bundle did not offer a price discount. Results suggest food bundles may be preferred because they require less cognitive effort to process, which could benefit consumers by simplifying the grocery shopping experience. Additional factors found to influence food bundle selection included whether the bundled items were perceived as being complementary and hunger levels. Food bundles could help lessen cognitive effort associated with grocery shopping and may especially appeal to those who do not enjoy food shopping.
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Meyer, N., A. N. Hrymak e L. Kärger. "Modeling Short-Range Interactions in Concentrated Newtonian Fiber Bundle Suspensions". International Polymer Processing 36, n. 3 (1 luglio 2021): 255–63. http://dx.doi.org/10.1515/ipp-2020-4051.
Testo completoAbstract (sommario):
Abstract Sheet Molding Compounds (SMC) offer a cost efficient way to enhance mechanical properties of a polymer with long discontinuous fibers, while maintaining formability to integrate functions, such as ribs, beads or other structural reinforcements. During SMC manufacturing, fibers remain often in a bundled configuration and the resulting fiber architecture determines part properties. Accurate prediction of this architecture by simulation of flow under consideration of the transient rheology and transient fiber orientations can speed up the development process. In particular, the interaction of bundles is of significance to predict molding pressures correctly in a direct simulation approach, which resolves individual fiber bundles. Thus, this work investigates the tangential short-range lubrication forces between fiber bundles with analytical and numerical techniques. A relation between the effective sheared gap between bundles and the bundle separation distance at the contact point is found and compared to experimental results from literature. The result is implemented in an ABAQUS contact subroutine to incorporate short-range interactions in a direct bundle simulation framework.
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Harker, Alyssa J., Harshwardhan H. Katkar, Tamara C. Bidone, Fikret Aydin, Gregory A. Voth, Derek A. Applewhite e David R. Kovar. "Ena/VASP processive elongation is modulated by avidity on actin filaments bundled by the filopodia cross-linker fascin". Molecular Biology of the Cell 30, n. 7 (21 marzo 2019): 851–62. http://dx.doi.org/10.1091/mbc.e18-08-0500.
Testo completoAbstract (sommario):
Ena/VASP tetramers are processive actin elongation factors that localize to diverse F-actin networks composed of filaments bundled by different cross-linking proteins, such as filopodia (fascin), lamellipodia (fimbrin), and stress fibers (α-actinin). Previously, we found that Ena takes approximately threefold longer processive runs on trailing barbed ends of fascin-bundled F-actin. Here, we used single-molecule TIRFM (total internal reflection fluorescence microscopy) and developed a kinetic model to further dissect Ena/VASP’s processive mechanism on bundled filaments. We discovered that Ena’s enhanced processivity on trailing barbed ends is specific to fascin bundles, with no enhancement on fimbrin or α-actinin bundles. Notably, Ena/VASP’s processive run length increases with the number of both fascin-bundled filaments and Ena “arms,” revealing avidity facilitates enhanced processivity. Consistently, Ena tetramers form more filopodia than mutant dimer and trimers in Drosophila culture cells. Moreover, enhanced processivity on trailing barbed ends of fascin-bundled filaments is an evolutionarily conserved property of Ena/VASP homologues, including human VASP and Caenorhabditis elegans UNC-34. These results demonstrate that Ena tetramers are tailored for enhanced processivity on fascin bundles and that avidity of multiple arms associating with multiple filaments is critical for this process. Furthermore, we discovered a novel regulatory process whereby bundle size and bundling protein specificity control activities of a processive assembly factor.
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Takemura, R., S. Okabe, T. Umeyama e N. Hirokawa. "Polarity orientation and assembly process of microtubule bundles in nocodazole-treated, MAP2c-transfected COS cells." Molecular Biology of the Cell 6, n. 8 (agosto 1995): 981–96. http://dx.doi.org/10.1091/mbc.6.8.981.
Testo completoAbstract (sommario):
Microtubule bundles reminiscent of those found in neuronal processes are formed in fibroblasts and Sf9 cells that are transfected with the microtubule-associated proteins tau, MAP2, or MAP2c. To analyze the assembly process of these bundles and its relation to the microtubule polarity, we depolymerized the bundles formed in MAP2c-transfected COS cells using nocodazole, and observed the process of assembly of microtubule bundles after removal of the drug in cells microinjected with rhodamine-labeled tubulin. Within minutes of its removal, numerous short microtubule fragments were observed throughout the cytoplasm. These short fragments were randomly oriented and were already bundled. Somewhat longer, but still short bundles, were then found in the peripheral cytoplasm. These bundles became the primordium of the larger bundles, and gradually grew in length and width. The polarity orientation of microtubules in the reformed bundle as determined by "hook" procedure using electron microscope was uniform with the plus end distal to the cell nucleus. The results suggest that some mechanism(s) exists to orient the polarity of microtubules, which are not in direct continuity with the centrosome, during the formation of large bundles. The observed process presents a useful model system for studying the organization of microtubules that are not directly associated with the centrosomes, such as those observed in axons.
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Yu, Chongwen, Weiying Tao e Timothy A. Calamari. "Treatment and Characterization of Kenaf for Nonwoven and Woven Applications". International Nonwovens Journal os-9, n. 4 (dicembre 2000): 1558925000OS—90. http://dx.doi.org/10.1177/1558925000os-900409.
Testo completoAbstract (sommario):
A kenaf bast fiber is comprised of a bundle of single fibers bound by lignin and pectins. It offers the advantages of being renewable, biodegradable and environmentally safe. However, it is difficult to process kenaf fibers because of the coarseness, stiffness and low cohesion of the fiber bundles. In this research, kenaf fiber bundles have been treated by both alkaline sulfide and a modified chemical degumming methods to improve fiber properties. Tensile properties, fineness, length and softness of the kenaf fiber bundles after the treatments were determined. It was found that both treatments improved the fiber fineness, softness and elongation; however, fiber bundle strength was decreased. The modified chemical degumming method was more effective. Under the optimum modified chemical degumming condition, the fineness of the kenaf fiber bundle was improved more than 50% and the fiber bundle was more than twice as soft as the raw material. These kenaf fiber bundles were much finer and softer and found to be easier to process than those obtained in earlier studies. The treated kenaf fiber bundles can be blended with cotton fibers and easily carded on a cotton card with minimum losses. The carded batts can be further processed for either nonwoven or woven applications.
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Khoury, Zana, Mariam Maloyan, Kathleen Conroy e Alexandra Epee-Bounya. "Improving delivery of preventative care services using population management strategies". BMJ Open Quality 11, n. 2 (maggio 2022): e001695. http://dx.doi.org/10.1136/bmjoq-2021-001695.
Testo completoAbstract (sommario):
BackgroundConsistent and timely delivery of comprehensive preventative care services is a challenge, particularly in underserved patient populations. Previous quality improvement (QI) research has focused on the development of bundled measures of preventative services delivery, but these bundles have not been studied on a population level. We aimed to improve preventative care service delivery on a clinic population level through the use of a bundled measure that includes immunisations, lead screening and use of screening tools among underserved patients under 2 years old.MethodsA QI study was conducted at a community-based academic primary care clinic. A population-level bundled measure was adapted from an existing tool. We used plan–do–study–act cycles to optimise results and tracked bundle outcome rates using a p-type statistical process control chart. Interventions included (1) staff education on measure components, (2) introduction of exam room-based phlebotomy to address lead screening completion rates and (3) population management strategies, including development of a patient registry and use of reminders and visit tracking to increase attendance at well-child visits.ResultsThe percent of bundle completion by 14 months of age increased from a baseline of 58%–77% following implementation of the QI initiatives. A mean shift was identified after the population manager began proactive targeted outreach for the 12-month visit.ConclusionTargeted systems for outreach aimed at bringing patients into the clinic and patient-centred strategies for visit completion are effective at ensuring timely delivery of comprehensive preventative care to an underserved paediatric population.
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Tilney, Lewis G., Patricia S. Connelly, Kelly A. Vranich, Michael K. Shaw e Gregory M. Guild. "Regulation of Actin Filament Cross-linking and Bundle Shape in Drosophila Bristles". Journal of Cell Biology 148, n. 1 (10 gennaio 2000): 87–99. http://dx.doi.org/10.1083/jcb.148.1.87.
Testo completoAbstract (sommario):
Previous studies demonstrate that in developing Drosophila bristles, two cross-linking proteins are required sequentially to bundle the actin filaments that support elongating bristle cells. The forked protein initiates the process and facilitates subsequent cross-linking by fascin. Using cross-linker–specific antibodies, mutants, and drugs we show that fascin and actin are present in excessive amounts throughout bundle elongation. In contrast, the forked cross-linker is limited throughout bundle formation, and accordingly, regulates bundle size and shape. We also show that regulation of cross-linking by phosphorylation can affect bundle size. Specifically, inhibition of phosphorylation by staurosporine results in a failure to form large bundles if added during bundle formation, and leads to a loss of cross-linking by fascin if added after the bundles form. Interestingly, inhibition of dephosphorylation by okadaic acid results in the separation of the actin bundles from the plasma membrane. We further show by thin section electron microscopy analysis of mutant and wild-type bristles that the amount of material that connects the actin bundles to the plasma membrane is also limited throughout bristle elongation. Therefore, overall bundle shape is determined by the number of actin filaments assembled onto the limited area provided by the connector material. We conclude that assembly of actin bundles in Drosophila bristles is controlled in part by the controlled availability of a single cross-linking protein, forked, and in part by controlled phosphorylation of cross-links and membrane actin connector proteins.
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Budnik, Pavel, Ilya Shegelman e Vyacheslav Baklagin. "Variability of forwarder truckload parameters in the Pryazha forestry division of the Republic of Karelia (Russia): A computer experiment". Central European Forestry Journal 66, n. 1 (1 marzo 2020): 12–22. http://dx.doi.org/10.2478/forj-2019-0027.
Testo completoAbstract (sommario):
AbstractThe goal of the present research is to analyze parameters of a bundle of logs for various models of forwarders in the Pryazha division of forestry of the Republic of Karelia. The investigated parameters were mass and volume of a bundle of logs, stacking factor of the bundle and the number of wood assortments in the bundle. The following models of forwarders have been investigated: John Deere 1210E, John Deere 1110E, Ponsse Elk, Ponsse Wisent, Amkodor 2661-01, Rottne F13D, Rottne F15D, Rottne F18D. We estimated the parameters of bundles formed from spruce sawlog 6.1 m long and bundles formed from spruce pulpwood 4 m long. Data on stem forms from harvester recorders have been collected to assess the parameters of a bundle of logs. Parameters of bundles have been determined based on computer experiment. The experiment consists of the following steps: random selection of the stem from the database; simulation of the cut-to-length process; simulation of log stacking process; calculation of parameters of a bundle of logs. We found that parameters of bundles vary to a quite substantial extent. Average variability of a bundle of logs formed of 6.1 m long spruce sawlog is 4.5 t, variability of the volume is 5.8 m3, and variability of the number of wood assortments in a bundle is 49 pcs. For a bundle made up of 4 m long spruce pulpwood variability of mass is on average 2.8 t, that of volume – 2.09 m3, that of the number of wood assortments – 57 pc. The presented results can inform transportation of wood on cutting areas, planning timber harvesting, as well as development new logging machines.
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Lynch, Thomas B., Jorge Chahla e Clayton W. Nuelle. "Anatomy and Biomechanics of the Posterior Cruciate Ligament". Journal of Knee Surgery 34, n. 05 (22 febbraio 2021): 499–508. http://dx.doi.org/10.1055/s-0041-1725007.
Testo completoAbstract (sommario):
AbstractPosterior cruciate ligament (PCL) injuries are often encountered in the setting of other knee pathology and sometimes in isolation. A thorough understanding of the native PCL anatomy is crucial in the successful treatment of these injuries. The PCL consists of two independent bundles that function in a codominant relationship to perform the primary role of resisting posterior tibial translation relative to the femur. A secondary role of the PCL is to provide rotatory stability. The anterolateral (AL) bundle has a more vertical orientation when compared with the posteromedial (PM) bundle. The AL bundle has a more anterior origin than the PM bundle on the lateral wall of the medial femoral condyle. The tibial insertion of AL bundle on the PCL facet is medial and anterior to the PM bundle. The AL and PM bundles are 12-mm apart at the center of the femoral origins, while the tibial insertions are more tightly grouped. The different spatial orientation of the two bundles and large distance between the femoral centers is responsible for the codominance of the PCL bundles. The AL bundle is the dominant restraint to posterior tibial translation throughout midrange flexion, while the PM bundle is the primary restraint in extension and deep flexion. Biomechanical testing has shown independent reconstruction of the two bundles that better reproduces native knee biomechanics, while significant differences in clinical outcomes remain to be seen. Stress X-rays may play an important role in clinical decision-making process for operative versus nonoperative management of isolated PCL injuries. Strong understanding of PCL anatomy and biomechanics can aid surgical management.
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Sherman, Michael B., Guichy Waller, Paul Matsudaira, Wah Chiu e Michael F. Schmid. "Electron Crystallographic Structure of the Limulus Acrosomal Bundle at 20 Å Resolution". Microscopy and Microanalysis 6, S2 (agosto 2000): 242–43. http://dx.doi.org/10.1017/s1431927600033705.
Testo completoAbstract (sommario):
Limulus sperm contains a dynamic macromolecular structure that rapidly extends a 50-μum process called the true discharge. The core of this structure is a bundle of ordered filaments composed of a complex of actin, scruin and calmodulin. We have shown that small segments along the bundle can be treated as single crystals with a unit cell spacing of 144 × 144 × 766 Å. A tomographic reconstruction of the bundle was done from multiple tilt series of images to ∼40 Å resolution. To extend the structural determination of the bundle at a higher resolution, we have used electron crystallographic analysis of single images of the bundles preserved in vitreous ice. Furthermore, we did not employ any helical or crystallographic symmetry (other than PI) in the reconstruction procedure.Acrosomal bundles from Limulus sperm cells were purified as described earlier. Images of frozen hydrated bundles were taken at 40,000x EM magnification in a JEOL 4000EX electron cryomicroscope using an electron dose of 6 - 10 electrons/Å2.
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Sherman, M. B., J. Jakana, S. Sun, P. Matsudaira, W. Chiu e M. F. Schmid. "Crystallographic Reconstruction of the Acrosomal Process from Limulus Polyphemus Sperm". Microscopy and Microanalysis 4, S2 (luglio 1998): 460–61. http://dx.doi.org/10.1017/s143192760002242x.
Testo completoAbstract (sommario):
The acrosomal process is an intracellular quasi-crystalline organelle in the head of the sperm of the horseshoe crab Limulus polyphemus. It consists of 100 - 130 actin-scruin filaments packed together in a pseudo-hexagonal lattice2 and is up to 60 (im long with a diameter of 0.1 μm. Scruin-scruin interactions are responsible for cross-linking the actin filaments together in the bundle. The goal of the current study is to reveal interfilament interactions in the bundle. We have taken tilt series images in the electron microscope3 to reconstruct its three-dimensional structure without assuming helical symmetry.The acrosomal process was purified as described.34 Bundles were embedded in vitreous ice over holes on a holey carbon film on copper grids. The specimen was kept at -167°C in a JEOL 4000EX electron microscope operating at 400 kV. Straight 6-10 (im long bundles were found using a TV-rate CCD camera in defocused diffraction mode.
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Rybolt, Thomas, e Heir Jordan. "Interactions and Binding Energies in Carbon Nanotube Bundles". Applied Nano 2, n. 2 (10 giugno 2021): 128–47. http://dx.doi.org/10.3390/applnano2020011.
Testo completoAbstract (sommario):
On any size scale, it is important to know how strongly structural components are held together. The purpose of this work was to develop a means to estimate the collective binding energy holding together a bundle of aligned carbon nanotubes (CNTs). Carbon nanotubes in isolation and in bundles have unique and useful properties and applications within supramolecular structures and nanotechnology. Equations were derived to represent the total number of pairwise interactions between the CNTs found in various size and shape bundles. The shapes considered included diamond, hexagon, parallelogram, and rectangle. Parameters were used to characterize the size of a bundle for each defined shape. Force field molecular modeling was used to obtain the total bundle binding energies for a number of sample bundles. From the number of interactions per bundle, the binding energy per interaction was determined. This process was repeated for armchair CNTs having a range of length and circumference values. A simple equation described the interaction energy based on the length and circumference of the component armchair type nanotubes. When combined with the bundle shape and size parameters, the total bundle binding energy could be found. Comparison with whole bundle molecular mechanics calculations showed our formula-based approach to be effective.
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Kim, Young-Joo, e Do-Nyun Kim. "Sensitivity Analysis for the Mechanical Properties of DNA Bundles". Journal of Nanomaterials 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/6287937.
Testo completoAbstract (sommario):
In structural DNA nanotechnology, programming a three-dimensional shape into DNA bundles has been a primary design objective. However, the mechanical properties of these DNA bundle structures are another important factor to be considered in the design process. While the mechanics of the individual DNA double helix has been explored extensively and hence its properties are well known, the mechanical properties of structural motifs such as DNA junctions and strand breaks important to bundle mechanics have not been well characterized due to experimental limitations, rendering it difficult to predict the mechanical properties of DNA bundles. Here, we investigate the effect of these structural motifs on the global bundle rigidities by performing sensitivity analysis on a six-helix DNA bundle structure using the finite element modeling approach. Results reveal the primary structural features and their parametric values required to reproduce the experimental bundle rigidities.
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Suzuki, Kazuya, Makito Miyazaki, Jun Takagi, Takeshi Itabashi e Shin’ichi Ishiwata. "Spatial confinement of active microtubule networks induces large-scale rotational cytoplasmic flow". Proceedings of the National Academy of Sciences 114, n. 11 (6 marzo 2017): 2922–27. http://dx.doi.org/10.1073/pnas.1616001114.
Testo completoAbstract (sommario):
Collective behaviors of motile units through hydrodynamic interactions induce directed fluid flow on a larger length scale than individual units. In cells, active cytoskeletal systems composed of polar filaments and molecular motors drive fluid flow, a process known as cytoplasmic streaming. The motor-driven elongation of microtubule bundles generates turbulent-like flow in purified systems; however, it remains unclear whether and how microtubule bundles induce large-scale directed flow like the cytoplasmic streaming observed in cells. Here, we adopted Xenopus egg extracts as a model system of the cytoplasm and found that microtubule bundle elongation induces directed flow for which the length scale and timescale depend on the existence of geometrical constraints. At the lower activity of dynein, kinesins bundle and slide microtubules, organizing extensile microtubule bundles. In bulk extracts, the extensile bundles connected with each other and formed a random network, and vortex flows with a length scale comparable to the bundle length continually emerged and persisted for 1 min at multiple places. When the extracts were encapsulated in droplets, the extensile bundles pushed the droplet boundary. This pushing force initiated symmetry breaking of the randomly oriented bundle network, leading to bundles aligning into a rotating vortex structure. This vortex induced rotational cytoplasmic flows on the length scale and timescale that were 10- to 100-fold longer than the vortex flows emerging in bulk extracts. Our results suggest that microtubule systems use not only hydrodynamic interactions but also mechanical interactions to induce large-scale temporally stable cytoplasmic flow.
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McGrath, Jamis. "Voltage-dependent bundle motion in mammalian auditory hair cells". Journal of the Acoustical Society of America 154, n. 4_supplement (1 ottobre 2023): A240. http://dx.doi.org/10.1121/10.0023410.
Testo completoAbstract (sommario):
Auditory hair cells have bundles of protrusions on their surface held together by proteinaceous links. Sound-induced vibrations deflect these bundles, transferring force through the links to open nearby mechanically sensitive ion channels and providing our sensation of sound. An increase in bundle compliance caused by channel gating can also be detected as motion. The channels open during depolarization and the bundle moves rapidly toward shorter stereocilia, followed by a larger but slower movement toward the taller stereocilia. To determine how voltage changes affect mammalian inner hair cell (IHC) bundles, we used whole cell patch clamp and high-speed imaging to apply electrical stimulation and measure bundle motion. We found two components in the motions of freestanding IHC bundles in response to depolarization, a fast offset away from the tallest row and a slower movement back toward the tallest row. Like in turtles, the slower motion was sensitive to channel block and suggested ion flux, particularly calcium, played a role. Our findings show IHCs can rapidly respond to changes in the bundle setpoint without ion influx. This work improves our understanding of the mechano-electrical transduction process and helps address the controversial role of calcium in regulating the channel current response.
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Baas, Nils A., Marcel Bökstedt e Tore August Kro. "Two-Categorical Bundles and their Classifying Spaces". Journal of K-Theory 10, n. 2 (23 febbraio 2012): 299–369. http://dx.doi.org/10.1017/is012001012jkt181.
Testo completoAbstract (sommario):
AbstractFor a 2-category 2C we associate a notion of a principal 2C-bundle. For the 2-category of 2-vector spaces, in the sense of M.M. Kapranov and V.A. Voevodsky, this gives the 2-vector bundles of N.A. Baas, B.I. Dundas and J. Rognes. Our main result says that the geometric nerve of a good 2-category is a classifying space for the associated principal 2-bundles. In the process of proving this we develop powerful machinery which may be useful in further studies of 2-categorical topology. As a corollary we get a new proof of the classification of principal bundles. Another 2-category of 2-vector spaces has been proposed by J.C. Baez and A.S. Crans. A calculation using our main theorem shows that in this case the theory of principal 2-bundles splits, up to concordance, as two copies of ordinary vector bundle theory. When 2C is a cobordism type 2-category we get a new notion of cobordism-bundles which turns out to be classified by the Madsen–Weiss spaces.
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Morton, Katherine, Stephanie MacNeill, Emily Sanderson, Padraig Dixon, Anna King, Sue Jenkins, Chris Metcalfe et al. "Evaluation of ‘care bundles’ for patients with chronic obstructive pulmonary disease (COPD): a multisite study in the UK". BMJ Open Respiratory Research 6, n. 1 (maggio 2019): e000425. http://dx.doi.org/10.1136/bmjresp-2019-000425.
Testo completoAbstract (sommario):
BackgroundChronic obstructive pulmonary disease (COPD) accounts for 10% of emergency hospital admissions in the UK annually. Nearly 33% of patients are readmitted within 28 days of discharge. We evaluated the effectiveness of implementing standardised packages of care called ‘care bundles’ on COPD readmission, emergency department (ED) attendance, mortality, costs and process of care.MethodsThis is a mixed-methods, controlled before-and-after study with nested case studies. 31 acute hospitals in England and Wales which introduced COPD care bundles (implementation sites) or provided usual care (comparator sites) were recruited and provided monthly aggregate data. 14 sites provided additional individual patient data. Participants were adults admitted with an acute exacerbation of COPD.ResultsThere was no evidence that care bundles reduced 28-day COPD readmission rates: OR=1.02 (95% CI 0.83 to 1.26). However, the rate of ED attendance was reduced in implementation sites over and above that in comparator sites (implementation: IRR=0.63 (95% CI 0.56 to 0.71); comparator: IRR=1.12 (95% CI 1.02 to 1.24); group–time interaction p<0.001). At implementation sites, delivery of all bundle elements was higher but was only achieved in 2.2% (admissions bundle) and 7.6% (discharge bundle) of cases. There was no evidence of cost-effectiveness. Staff viewed bundles positively, believing they help standardise practice and facilitate communication between clinicians. However, they lacked skills in change management, leading to inconsistent implementation.DiscussionCOPD care bundles were not effectively implemented in this study. They were associated with a reduced number of subsequent ED attendances, but not with change in readmissions, mortality or reduced costs. This is unsurprising given the low level of bundle uptake in implementation sites, and it remains to be determined if COPD care bundles affect patient care and outcomes when they are effectively implemented.Trial registration numberISRCTN13022442.
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Guo, Shangjing, Guoliang Zhou, Jinglu Wang, Xianju Lu, Huan Zhao, Minggang Zhang, Xinyu Guo e Ying Zhang. "High-Throughput Phenotyping Accelerates the Dissection of the Phenotypic Variation and Genetic Architecture of Shank Vascular Bundles in Maize (Zea mays L.)". Plants 11, n. 10 (18 maggio 2022): 1339. http://dx.doi.org/10.3390/plants11101339.
Testo completoAbstract (sommario):
The vascular bundle of the shank is an important ‘flow’ organ for transforming maize biological yield to grain yield, and its microscopic phenotypic characteristics and genetic analysis are of great significance for promoting the breeding of new varieties with high yield and good quality. In this study, shank CT images were obtained using the standard process for stem micro-CT data acquisition at resolutions up to 13.5 μm. Moreover, five categories and 36 phenotypic traits of the shank including related to the cross-section, epidermis zone, periphery zone, inner zone and vascular bundle were analyzed through an automatic CT image process pipeline based on the functional zones. Next, we analyzed the phenotypic variations in vascular bundles at the base of the shank among a group of 202 inbred lines based on comprehensive phenotypic information for two environments. It was found that the number of vascular bundles in the inner zone (IZ_VB_N) and the area of the inner zone (IZ_A) varied the most among the different subgroups. Combined with genome-wide association studies (GWAS), 806 significant single nucleotide polymorphisms (SNPs) were identified, and 1245 unique candidate genes for 30 key traits were detected, including the total area of vascular bundles (VB_A), the total number of vascular bundles (VB_N), the density of the vascular bundles (VB_D), etc. These candidate genes encode proteins involved in lignin, cellulose synthesis, transcription factors, material transportation and plant development. The results presented here will improve the understanding of the phenotypic traits of maize shank and provide an important phenotypic basis for high-throughput identification of vascular bundle functional genes of maize shank and promoting the breeding of new varieties with high yield and good quality.
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Khanal, Kapil, Santosh Bhusal, Manoj Karkee e Qin Zhang. "Raspberry Primocane Bundling and Taping Mechanisms". Transactions of the ASABE 61, n. 4 (2018): 1265–74. http://dx.doi.org/10.13031/trans.12608.
Testo completoAbstract (sommario):
Abstract. In red raspberry production, two-year-old canes (called floricanes) are pruned and new one-year-old canes (called primocanes) are bundled and tied together to provide a firm canopy structure for the next year’s production. These processes are currently manual, labor-intensive, and costly. Pruning, bundling, and tying cost farmers more than $1,482 ha-1 year-1, the majority of which is spent on bundling and tying. Although some mechanized techniques are available for tying the branches of fruit trees and vines, and for baling leaves and straw, research on the development of mechanized systems for managing cane berry plants has not been reported yet. In this work, a taping mechanism was designed and fabricated for tying bundles of red raspberry canes. This taping mechanism was integrated with a hydraulically controlled cane bundling mechanism for field evaluation. The taping mechanism consisted of a tape wrapper wheel, a tape holding arm, and a tape cutting assembly, whose motions were timed in proper sequence to complete the tape wrapping process. The rotation of the wrapper wheel wound the tape around a bundle of primocanes gathered by the bundling mechanism. After a predefined number of wrappings, the cutting assembly was actuated to sever the tape, and the mechanism released the bundled plant. Field testing demonstrated a bundling success rate of 94%; of 249 canes targeted for bundling, 235 were properly bundled. Of the 92 tape wrapping attempts, 76 were successful in taping bundles of canes, a success rate of 83%. The prototype system was fabricated and evaluated for its functionality without optimizing for speed. Currently, this system requires ~3 min per taping (compared to ~30 s for manual taping). Although some improvements in the size, speed, and design of the mechanisms are essential to increase the overall accuracy and productivity of the system, the results showed good promise toward the development of an automated machine for red raspberry cane bundling and taping. Keywords: Agricultural machinery, Bundling, Mechanism, Red raspberries canes, Taping.
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Shaw, Ali, Katherine Morton, Anna King, Melanie Chalder, James Calvert, Sue Jenkins e Sarah Purdy. "Using and implementing care bundles for patients with acute admission for COPD: qualitative study of healthcare professionals’ experience in four hospitals in England". BMJ Open Respiratory Research 7, n. 1 (marzo 2020): e000515. http://dx.doi.org/10.1136/bmjresp-2019-000515.
Testo completoAbstract (sommario):
BackgroundCare bundles are sets of evidence-based interventions to improve quality of hospital care at admission and discharge. Within a wider multi-method evaluation of care bundles for adults with an emergency admission for acute exacerbations of chronic obstructive pulmonary disease, a qualitative study was conducted. The aim was to evaluate how bundles were used, and healthcare professionals’ experiences of the impact of bundles on the process of care delivery.MethodsWithin the wider evaluation, four acute hospitals that were using COPD care bundles were purposefully sampled for geographical variation. Qualitative data were gathered through non-participant observation of patient care and interviews with healthcare professionals, patients and carers. This paper reports a thematic analysis of data from observation and interviews with professionals.ResultsHealthcare professionals generally experienced care bundles as positive for standardising working practices and patient care, valuing how bundles could support a clear care pathway for patients, enable transitions between settings and identify postdischarge support required by patients. Successful use of bundles was perceived as more likely with the presence of either (or both) a clinical champion for bundles and system-based initiatives such as financial incentives, within a local culture of quality improvement. Challenges in accurately diagnosing COPD hampered bundle use, including delivery of bundles to those subsequently considered ineligible, or missed opportunities to deliver admission bundles to those with COPD.ConclusionCare bundles shape admission and discharge care processes for patients with COPD, from the perspective of staff involved in their delivery. However, different organisational, staff and clinical factors aid or hinder bundle use in an acute hospital context, suggesting potentially resolvable reasons for variable implementation of bundles. Finally, bundles may enhance staff experience of care delivery, even if the impact on patient outcomes remains uncertain.
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Zhong, Li Sheng, Yun Hua Xu, Peng Yu, Xiao Jie Liu, Fang Xia Ye e Hong Hua Yan. "Microstructure and Abrasive Wear Characteristics of In Situ WC Bundles – Reinforced Iron Matrix Composites". Advanced Materials Research 284-286 (luglio 2011): 265–68. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.265.
Testo completoAbstract (sommario):
An in-situ synthesis process combining an infiltration casting with a subsequent heat treatment was applied to fabricate special tungsten carbide (WC) bundles-reinforced iron matrix composites in this work. The microstructure and wear-resistance of the tungsten carbide bundles reinforced iron matrix composites were studied by using scanning electron microscopy, X-ray diffraction and wear tester. Results showed that the tungsten carbide bundles distributed in the matrix with the center-to-center spacing 2.2 mm, and the diameter of each tungsten carbide bundle is about 1 mm. Most of the tungsten carbides agglomerated, but still there were tungsten carbide particles and the size of tungsten carbide particle was about 10—15 μm. The weight loss of the tungsten carbides bundle reinforced iron matrix composites increased with the increase of the loads and the weight loss of the composites is much less than those of the gray cast iron under the same condition. The wear mechanism of tungsten carbide bundles-reinforced iron matrix composites appears as: micro-cutting, micro-ploughing, broken tungsten carbide and broken particles re-embedded in the matrix.
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Mei, Zhongjian, Cheng Li, Jie Zhao, Zixuan Li, Kaiyi Chen, Xin Huang e Zhiyue Zhao. "The Temporal and Spatial Evolution Characteristics and Driving Factors of Ecosystem Service Bundles in Anhui Province, China". Land 13, n. 6 (23 maggio 2024): 736. http://dx.doi.org/10.3390/land13060736.
Testo completoAbstract (sommario):
Identifying ecosystem service bundles and their long-term evolutionary characteristics is essential for the overall enhancement of regional ecosystem services, as well as the division and management of functional areas, providing a basis for decision-making in formulating ecological and environmental protection policies, as well as regional development planning. Based on land use, remote sensing, and meteorological data obtained from Anhui Province, this study assessed six important ecosystem service functions, including food production (FP), water yield (WY), carbon sequestration (CS), soil conservation (SC), habitat quality (HQ), and landscape aesthetics (LA), at the township scale in 2000, 2010, and 2020. On this basis, the k-means clustering method was used to identify ecosystem service bundles, analyze the spatio-temporal evolution trajectory of service bundles, and explore the driving factors of the spatio-temporal evolution of ecosystem service bundles using GeoDetector 2015 The results indicate the following: (1) At the spatial level, diverse ecosystem services demonstrate pronounced spatial differentiation. The distribution pattern of HQ, carbon fixation, and SC services is generally lower in the north and higher in the south, with areas of high value predominantly located in the western Dabie Mountains and the mountains of Southern Anhui. Conversely, FP services exhibit the reverse pattern, and WY services display a gradual increase from north to south, while cultural services are more dispersed, with areas of high value primarily located in the western Dabie Mountains, the Yangtze River Basin, and other locations. On the temporal scale, WY, SC, and FP services mainly exhibit an increasing trend, marked by a significant increase, whereas other services tend to present a decreasing trend. (2) Anhui Province can be categorized into four distinct types of service bundles: the grain production bundle (GPB), mountain ecological conservation bundle (MECB), urban living bundle (ULB), and core protection bundle (CPB). Ecosystem service bundles exhibit clear spatial differentiation, and identical service bundles demonstrate substantial clustering in space. Between 2000 and 2020, ecosystem service bundles displayed a marked spatio-temporal evolution, with the prevalence of GPBs diminishing, whereas the share of ULBs progressively increased, and the number of MECBs and CPBs remained largely stable. (3) In the spatio-temporal evolution process, the average annual precipitation, the proportion of forest land, and slope constitute the principal natural factors influencing the spatio-temporal evolution of ecosystem service bundles, while the proportion of construction land represents the primary socio-economic factor, with natural factors exerting a more significant influence than socio-economic factors.
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Inaroh, Inaroh, Abdurrachman Faridi e Sri Wuli Fitriati. "The Use of Structures and Functions of Lexical Bundles in Conversation Texts in Bahasa Inggris Textbook Published By Kemendikbud". English Education Journal 11, n. 1 (22 dicembre 2020): 105–13. http://dx.doi.org/10.15294/eej.v11i1.43411.
Testo completoAbstract (sommario):
This study investigated the use of structures of lexical bundles, functions of lexical bundles, and the relationship between structures and functions of bundles in conversation texts. For the purposes of the study, the BahasaInggris textbook, published by the Ministry of Education and Culture(2018), was chosen to be analyzed. In the process of collecting the data, a set of tables was used. The first table was used to collect data to analyze structures of lexical bundles based on Biber's (2006) theory. The second table was used to collect data regarding Biber and Conrad's (2005) theory for functions of lexical bundles. Procedures for analyzing data consisted of steps, including reading, categorizing, and analyzing. This study revealed that, firstly, personal pronoun + lexical VP (e.g. we are going to) identified as the most frequent structure of bundle appeared in the conversation texts.Secondly, stance expression had a high proportion of the most recurring function of the bundle. They are used for expressing desire, intention, ability, obligation, and showing certain and uncertain feelings. Moreover, there were relationships between the functions of bundles with particular structures. In conclusion, improving the teaching quality can be built based on the appropriateness of the textbook. The teacher needs to pay attention to the English book that they will use, especially those that provide enough materials for enhancing students’ formulaic competence
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Neeley, Grant, e Lilliard Richardson. "Cannabis Policy Adaptation: Exploring Frameworks of State Policy Characteristics". Public Administration Quarterly 47, n. 3 (15 giugno 2023): 253–83. http://dx.doi.org/10.37808/paq.47.3.2.
Testo completoAbstract (sommario):
Thirty-six states adopted some form of legalized cannabis by 2020, and policy characteristics varied considerably across the states. Nineteen of those states initially adopted legalized cannabis via ballot measure, and seventeen initially adopted via legislation. Implementation of cannabis policy across these types of policy adoption differed substantially in process and policy design. To characterize the policy environment, we develop a unique coding scheme for legalized cannabis with policy characteristics aggregated into three policy bundles. The pharmaceutical bundle treats cannabis as a legal but regulated drug. The permissive bundle allows greater individual discretion on cannabis use. The fiscal bundle treats cannabis as a potential revenue source. Using these policy bundles from the years 1994-2020, we explore how states continue to modify their policy approaches in the implementation period and assess the factors shaping policy adaptation over time, such as administrative capacity, partisan control, state fiscal health, and economic factors.
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Hollesen, Rikke von Benzon, Rie Laurine Rosenthal Johansen, Christina Rørbye, Louise Munk, Pierre Barker e Anette Kjaerbye-Thygesen. "Successfully reducing newborn asphyxia in the labour unit in a large academic medical centre: a quality improvement project using statistical process control". BMJ Quality & Safety 27, n. 8 (3 febbraio 2018): 633–42. http://dx.doi.org/10.1136/bmjqs-2017-006599.
Testo completoAbstract (sommario):
BackgroundA safe delivery is part of a good start in life, and a continuous focus on preventing harm during delivery is crucial, even in settings with a good safety record. In January 2013, the labour unit at Copenhagen University Hospital, Hvidovre, undertook a quality improvement (QI) project to prevent asphyxia and reduced the percentage of newborns with asphyxia by 48%.MethodsThe change theory consisted of two primary elements: (1) the clinical content, including three clinical bundles of evidence-based care, a ‘delivery bundle’, an ‘oxytocin bundle’ and a ‘vacuum extraction bundle’; (2) an implementation theory, including improving skills in interpretation of cardiotocography, use of QI methods and participation in a national learning network. The Model for Improvement and Deming’s system of profound knowledge were used as a methodological framework. Data on compliance with the care bundles and the number of deliveries between newborns with asphyxia (Apgar <7 after 5 min or pH <7) were analysed using statistical process control.ResultsCompliance with all three clinical care bundles improved to 95% or more, and the percentages of newborns with pH <7 and Apgar <7 after 5 min were reduced by 48% and 31%, respectively. In general, the QI approach strengthened multidisciplinary teamwork, systematised workflow and structured communication around the deliveries. Changes included making a standard memo in the medical record, the use of a bedside whiteboard, bedside handovers, shared decisions with a peer when using an oxytocin infusion and the use of a checklist before vacuum extractions.ConclusionThis QI project illustrates how aspects of patient safety, such as the prevention of asphyxia, can be improved using QI methods to more reliably implement best practice, even in high-performing systems.
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Zhou, Feng-Quan, Clare M. Waterman-Storer e Christopher S. Cohan. "Focal loss of actin bundles causes microtubule redistribution and growth cone turning". Journal of Cell Biology 157, n. 5 (28 maggio 2002): 839–49. http://dx.doi.org/10.1083/jcb.200112014.
Testo completoAbstract (sommario):
Ît is commonly believed that growth cone turning during pathfinding is initiated by reorganization of actin filaments in response to guidance cues, which then affects microtubule structure to complete the turning process. However, a major unanswered question is how changes in actin cytoskeleton are induced by guidance cues and how these changes are then translated into microtubule rearrangement. Here, we report that local and specific disruption of actin bundles from the growth cone peripheral domain induced repulsive growth cone turning. Meanwhile, dynamic microtubules within the peripheral domain were oriented into areas where actin bundles remained and were lost from areas where actin bundles disappeared. This resulted in directional microtubule extension leading to axon bending and growth cone turning. In addition, this local actin bundle loss coincided with localized growth cone collapse, as well as asymmetrical lamellipodial protrusion. Our results provide direct evidence, for the first time, that regional actin bundle reorganization can steer the growth cone by coordinating actin reorganization with microtubule dynamics. This suggests that actin bundles can be potential targets of signaling pathways downstream of guidance cues, providing a mechanism for coupling changes in leading edge actin with microtubules at the central domain during turning.
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Lee, Sang Mok, Hoon Jae Park, Seung Soo Kim, Tae Hoon Choi, E. Z. Kim e Geun An Lee. "The Potentiality of Micro-Scaled Multi-Filament Wire Forming Using Repetitive Hydrostatic Extrusion Process". Advanced Materials Research 26-28 (ottobre 2007): 77–80. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.77.
Testo completoAbstract (sommario):
Multi-filament fabrication process using repetitive hydrostatic extrusion of Cu/Al at high temperature was conducted to obtain micro-scaled Aluminum wires. In the process an aluminum rod claded with a copper tube was extruded repetitively three times where a number of the single extruded rods were bundled together and subjected to hydrostatic extrusion to obtain multi-filament wire bundle. Aafter final bundle extrusion the diameter of the aluminum rod was effectively reduced from 33.6 mm to 30μm.
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Sahay, Arvind, Sumitava Mukherjee e Prem Prakash Dewani. "Price discount framings on product bundles with shipping surcharges in the Indian market". Journal of Indian Business Research 7, n. 1 (16 marzo 2015): 4–20. http://dx.doi.org/10.1108/jibr-05-2014-0026.
Testo completoAbstract (sommario):
Purpose – The purpose of this paper is to study how consumers process price frames of product bundles (product plus surcharge) and discount offers to weigh contentious positions between the weighted-additive and the reference-dependent models. Further, some research suggests bundling, while others suggest partitioning to be a more effective pricing strategy. This research evaluated the relative influences of different price frames to examine which model is supported and what are the boundary conditions for price framing. Design/methodology/approach – Two online studies were conducted on Indian adults who had prior experiences of online purchases. They were asked to judge attractiveness of bundles (product along with shipping surcharge). Discounts were shown on the product, the surcharge or on the overall bundle either as partitioned prices or as a bundle. Findings – Across two studies on low- and high-priced products, discounts on shipping surcharge increased attractiveness of the bundle compared to a similar discount on the product or on the overall bundle, supporting the reference-dependent model. Further, for a low-priced product, bundling increased attractiveness, while for a high-priced product, partitioning was more attractive. Research limitations/implications – More research is needed to examine whether these results translate to other kinds of products, surcharges or discount promotions and in different populations. Originality/value – This research makes important contributions to theoretical and practical aspects of bundling and partitioned pricing research. It also adds much needed data about evaluation of product bundles with shipping surcharges among Indian customers.
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Zhang, Hai Dong, Yu Shen e Xu Xu Zheng. "Synthesis of Mesoporous Silica Nanotube Bundles". Advanced Materials Research 233-235 (maggio 2011): 2375–78. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.2375.
Testo completoAbstract (sommario):
Mesoporous silica nanotube bundles with short channels were synthesized through a surfactant-templated process with the addition of dodecane. Transmission electron microscope (TEM) and high resolution scanning electron microscope (HRSEM) studies show that the channels of the silica nanotubes are parallel gathered in nano-size bundles. Each particle of these nano-size bundles contains less than 10 silica nanotubes. The length of the silica nanotube channel is about 200 nm while the pore size of the channels is about 11 nm. Dodecane solubilized in the hydrophobic cores of P123 micelles leads to large pore size and the unique bundle structure of the silica nanotubes.
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Zhang, Zhou Wei, Jia Xing Xue e Ya Hong Wang. "Calculation and Design Method Study of the Coil-Wound Heat Exchanger". Advanced Materials Research 1008-1009 (agosto 2014): 850–60. http://dx.doi.org/10.4028/www.scientific.net/amr.1008-1009.850.
Testo completoAbstract (sommario):
A calculation method for counter-current type coil-wound heat exchanger is presented for heat exchange process. The numerical simulation method is applied to determine the basic physical parameters of wound bundles. By controlling the inlet fluid velocity varying in coil-wound heat exchanger to program and calculate the iterative process. The calculation data is analyzed by comparison of numerical result and the unit three dimensional pipe bundle model was built. Studies show that the introduction of numerical simulation can simplify the pipe winding process and accelerate the calculation and design of overall configuration in coil-wound heat exchanger. This method can be applied to the physical modeling and heat transfer calculation of pipe bundles in coil wound heat exchanger, program to calculate the complex heat transfer changing with velocity and other parameters, and optimize the overall design and calculation of spiral bundles.
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Ishikawa, Tatsuya, KyoungHou Kim e Yutaka Ohkoshi. "Visualization of a pillar-shaped fiber bundle in a model needle-punched nonwoven fabric using X-ray micro-computed tomography". Textile Research Journal 87, n. 11 (2 agosto 2016): 1387–93. http://dx.doi.org/10.1177/0040517516652351.
Testo completoAbstract (sommario):
In the needle-punching process, the barbs of a needle catch fibers and orient them along the thickness direction of the fabric. The oriented fibers form a pillar-shaped fiber bundle, which acts as a bonding point of the fabric. The structure of the pillar-shaped fiber bundle thus governs the mechanical properties of needle-punched nonwoven fabric, and both are largely affected by the needle-punching conditions. However, the three-dimensional structure of pillar-shaped fiber bundles and their development under different needle-punching conditions have not been revealed. In the present study, we visualized the three-dimensional structure of a pillar-shaped fiber bundle in needle-punched nonwoven fabric, employing X-ray micro-computed tomography (XCT) on the basis of the difference in the X-ray absorption coefficient between polyethylene terephthalate (PET) and polyethylene fibers. For a material density ratio of less than 1.4 and PET fibers having a diameter of 40 µm, the pillar-shaped bundles of PET fibers were visualized by erasing 20-µm polyethylene fibers in XCT images. Furthermore, we investigated the effects of the penetration depth of the needle on the development of pillar-shaped fiber bundles. The number of fibers constituting a pillar largely increased at a penetration depth of 19.0 mm, and pillars protruded from the bottom surface of the fabric and formed a stitch structure. The XCT applied in this study is thus effective in analyzing the structure of pillar-shaped fiber bundles quantitatively without affecting the structure of the nonwoven fabric.
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Zhang, Xu, Bin Jiang, Luhong Zhang e Xiaoming Xiao. "Fluid-Elastic Instability Tests on Parallel Triangular Tube Bundles with Different Mass Ratio Values under Increasing and Decreasing Flow Velocities". Shock and Vibration 2016 (2016): 1–20. http://dx.doi.org/10.1155/2016/1680218.
Testo completoAbstract (sommario):
To study the effects of increasing and decreasing flow velocities on the fluid-elastic instability of tube bundles, the responses of an elastically mounted tube in a rigid parallel triangular tube bundle with a pitch-to-diameter ratio of 1.67 were tested in a water tunnel subjected to crossflow. Aluminum and stainless steel tubes were tested, respectively. In the in-line and transverse directions, the amplitudes, power spectrum density functions, response frequencies, added mass coefficients, and other results were obtained and compared. Results show that the nonlinear hysteresis phenomenon occurred in both tube bundle vibrations. When the flow velocity is decreasing, the tubes which have been in the state of fluid-elastic instability can keep on this state for a certain flow velocity range. During this process, the response frequencies of the tubes will decrease. Furthermore, the response frequencies of the aluminum tube can decrease much more than those of the stainless steel tube. The fluid-elastic instability constants fitted for these experiments were obtained from experimental data. A deeper insight into the fluid-elastic instability of tube bundles was also obtained by synthesizing the results. This study is beneficial for designing and operating equipment with tube bundles inside, as well as for further research on the fluid-elastic instability of tube bundles.
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Xu, Guangtong, Teng Long, Zhu Wang e Li Liu. "Target-bundled genetic algorithm for multi-unmanned aerial vehicle cooperative task assignment considering precedence constraints". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 234, n. 3 (16 ottobre 2019): 760–73. http://dx.doi.org/10.1177/0954410019883106.
Testo completoAbstract (sommario):
This paper presents a modified genetic algorithm using target-bundle-based encoding and tailored genetic operators to effectively tackle cooperative multiple task assignment problems of heterogeneous unmanned aerial vehicles. In the cooperative multiple task assignment problem, multiple tasks including reconnaissance, attack, and verification have to be sequentially performed on each target (e.g. ground control stations, tanks, etc.) by one or multiple unmanned aerial vehicles. Due to the precedence constraints of different tasks, a singular task-execution order may cause deadlock situations, i.e. one or multiple unmanned aerial vehicles being trapped in infinite waiting loops. To address this problem, a target-bundled genetic algorithm is proposed. As a key element of target-bundled genetic algorithm, target-bundle-based encoding is derived to fix multiple tasks on each target as a target-bundle. And individuals are generated by fixing the task-execution order on each target-bundle subject to task precedence constraints. During the evolution process, bundle-exchange crossover and multi-type mutation operators are customized to generate deadlock-free offspring. Besides, the time coordination method is developed to ensure that task-execution time satisfies task precedence constraints. The comparison results on numerical simulations demonstrate that target-bundled genetic algorithm outperforms particle swarm optimization and random search methods in terms of optimality and efficiency.
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Hahn, E., R. Andres, T. de Kok, A. Brown e J. Doyle. "P058: Improving patient safety and streamlining care at a community hospital through spread and scale of a trauma care bundle: a quality improvement pilot project". CJEM 18, S1 (maggio 2016): S98. http://dx.doi.org/10.1017/cem.2016.234.
Testo completoAbstract (sommario):
Introduction: Non-trauma centers (NTC) and community hospitals commonly deliver medical care during the “golden hour” of trauma, which has significant implications on the health outcomes of patients. The Niagara Health System (NHS) and its 3 community NTC hospitals provide trauma care to over 100 patients annually during this critical period. NTCs lack standardized resources commonly found in trauma centers. Checklists and bundles have been effective in streamlining process to ensure health care providers provide the right care, at the right time and address critical points during patient care. A trauma care bundle was designed and implemented in the NHS as a means to improve trauma care and patient outcomes. Methods: A quality improvement (QI) approach was used to design, implement and evaluate a trauma care bundle at one of the NHS’s community hospitals. These interventions were adapted and modified for community trauma care purposes. We piloted the trauma care bundle using rapid cycle improvements, known as Plan-Do-Study-Act (PDSA) cycles. We assessed outcome and process measures through a chart audit of all trauma care patients in the NHS from July 2015-December 2015. A safety attitudes questionnaire (SAQ) was administered to health system staff who were involved in the pilot to assess balancing measures. Results: Improvements to the bundle and its implementation from 4 PDSA cycles resulted in increased utilization. This continuous monitoring of the bundle and ongoing, conscious efforts to improve the intervention were used to spread and scale across all 3 sites of the NHS. 30% of patients received the trauma care bundle during phase 1 of the pilot from July 1- October 31, 2015. We are presently analyzing preliminary data to understand how the trauma care bundle impacts health outcomes and process and will present a comparative analysis between patient groups. Conclusion: Trauma care bundles may foster safer and more efficient patient care in community hospitals where the golden hour of trauma often occurs. This community trauma care bundle shows promising results for streamlining the care process to ensure patients receive appropriate care during the golden hour. Spread and scale of this bundle across other community hospitals will likely yield similar improvements in patient care.
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Sun, Lili, Grigorios Panagakos e Glenn Lipscomb. "Effect of Packing Nonuniformity at the Fiber Bundle–Case Interface on Performance of Hollow Fiber Membrane Gas Separation Modules". Membranes 12, n. 11 (13 novembre 2022): 1139. http://dx.doi.org/10.3390/membranes12111139.
Testo completoAbstract (sommario):
High-fidelity simulations of momentum and mass transfer within a hollow fiber gas separation membrane module are here reported. The simulations capture the potential detrimental effects of poor fiber packing at the bundle–case interface on fluid distribution and performance. Results are presented for both circular and planar fiber bundles. The length over which bundle–case gaps affects flow is determined. The length increases dramatically with increasing fiber packing fraction. As the packing fraction approaches 0.6, the impact extends over the entire bundle diameter for small modules (<1000 fibers). The results clearly demonstrate the detrimental effect of poor packing along the case and can be used to develop module manufacturing guidelines. To reduce computational costs, an equivalent planar bundle module approximation is developed. The approximate simulations agree well with results from full 3-D simulations and can reduce computational costs without sacrificing fidelity.
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Morton, Katherine, Emily Sanderson, Padraig Dixon, Anna King, Sue Jenkins, Stephanie J. MacNeill, Alison Shaw et al. "Care bundles to reduce re-admissions for patients with chronic obstructive pulmonary disease: a mixed-methods study". Health Services and Delivery Research 7, n. 21 (giugno 2019): 1–128. http://dx.doi.org/10.3310/hsdr07210.
Testo completoAbstract (sommario):
BackgroundChronic obstructive pulmonary disease (COPD) is the commonest respiratory disease in the UK, accounting for 10% of emergency hospital admissions annually. Nearly one-third of patients are re-admitted within 28 days of discharge.ObjectivesThe study aimed to evaluate the effectiveness of introducing standardised packages of care (i.e. care bundles) as a means of improving hospital care and reducing re-admissions for COPD.DesignA mixed-methods evaluation with a controlled before-and-after design.ParticipantsAdults admitted to hospital with an acute exacerbation of COPD in England and Wales.InterventionCOPD care bundles.Main outcome measuresThe primary outcome was re-admission to hospital within 28 days of discharge. The study investigated secondary outcomes including length of stay, total number of bed-days, in-hospital mortality, 90-day mortality, context, process and costs of care, and staff, patient and carer experience.Data sourcesRoutine NHS data, including numbers of COPD admissions and re-admissions, in-hospital mortality and length of stay data, were provided by 31 sites for 12 months before and after the intervention roll-out. Detailed pseudo-anonymised data on care during admission were collected from a subset of 14 sites, in addition to information about delivery of individual components of care collected from random samples of medical records at each location. Six case study sites provided data from interviews, observation and documentary review to explore implementation, engagement and perceived impact on delivery of care.ResultsThere is no evidence that care bundles reduced 28-day re-admission rates for COPD. All-cause re-admission rates, in-hospital mortality, length of stay, total number of bed-days, and re-admission and mortality rates in the 90 days following discharge were similar at implementation and comparator sites, as were resource utilisation, NHS secondary care costs and cost-effectiveness of care. However, the rate of emergency department (ED) attendances decreased more in implementation sites than in comparator sites {implementation: incidence rate ratio (IRR) 0.63 [95% confidence interval (CI) 0.56 to 0.70]; comparator: IRR 1.14 (95% CI 1.04 to 1.26) interactionp < 0.001}. Admission bundles appear to be more complex to implement than discharge bundles, with 3.7% of comparator patients receiving all five admission bundle elements, compared with 7.6% of patients in implementation sites, and 28.3% of patients in implementation sites receiving all five discharge bundle elements, compared with 0.8% of patients in the comparator sites. Although patients and carers were unaware that care was bundled, staff view bundles positively, as they help to standardise working practices, support a clear care pathway for patients, facilitate communication between clinicians and identify post-discharge support.LimitationsThe observational nature of the study design means that secular trends and residual confounding cannot be discounted as potential sources of any observed between-site differences. The availability of data from some sites was suboptimal.ConclusionsCare bundles are valued by health-care professionals, but were challenging to implement and there was a blurring of the distinction between the implementation and comparator groups, which may have contributed to the lack of effect on re-admissions and mortality. Care bundles do appear to be associated with a reduced number of subsequent ED attendances, but care bundles are unlikely to be cost-effective for COPD.Future workA longitudinal study using implementation science methodology could provide more in-depth insights into the implementation of care bundles.Trial registrationCurrent Controlled Trials ISRCTN13022442.FundingThis project was funded by the National Institute for Health Research Health Services and Delivery Research programme and will be published in full inHealth Services and Delivery Research; Vol. 7, No. 21. See the NIHR Journals Library website for further project information.
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Fujio, Yuki, Chao-Nan Xu e Nao Terasaki. "Flexible Mechanoluminescent SrAl2O4:Eu Film with Tracking Performance of CFRP Fracture Phenomena". Sensors 22, n. 15 (22 luglio 2022): 5476. http://dx.doi.org/10.3390/s22155476.
Testo completoAbstract (sommario):
Non-destructive testing of carbon-fiber-reinforced plastic (CFRP) laminates with bidirectional fiber bundles (twill-weave) using a mechanoluminescence (ML) technique was proposed. The dynamic strain distributions and fracture phenomena of the CFRP laminates in the tensile testing were evaluated by the fabricated ML sensor consisting of SrAl2O4:Eu (SAOE) powder and epoxy resin. The ML images for the ML sensor attached to the CFRP laminates with bidirectional fiber bundles gave a net-like ML intensity distribution similar to the original twill weave pattern. Specifically, it was found that the ML intensity on the longitudinal fiber bundle, which is the same as the tensile direction, is higher than that on the transverse fiber bundle. This indicates that the ML sensor can visualize the load share between fiber bundles in different directions of the CFRP laminate with high spatial resolution. Meanwhile, the ML sensor could also visualize the ultrafast discontinuous fracture process of the CFRP laminates and its stress distribution. The amount of SAOE powder in the ML sensor affects the tracking performance of the crack propagation. A higher SAOE amount leads to a fracture of the ML sensor itself, and a lower SAOE amount leads to poor ML characteristics.
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Abdul Kadir, Kureshi, e Mohd Hasan. "Performance Optimization and Comparison of CNT Interconnect with Copper at VDSM Technology". INTERNATIONAL JOURNAL OF MANAGEMENT & INFORMATION TECHNOLOGY 6, n. 2 (15 ottobre 2013): 826–34. http://dx.doi.org/10.24297/ijmit.v6i2.3812.
Testo completoAbstract (sommario):
As the CMOS process technology continues to scale, standard copper (Cu) interconnect will become a major hurdle for the best performance at very deep submicron (VDSM) technology node. The carbon nanotube (CNT) bundles have potential to provide an attractive solution for the higher resistivity and electromigration problems faced by traditional copper interconnects in VDSM technology node. This paper presents important guidelines to minimize the resistance, capacitance and inductance of a mixed CNT bundle interconnect for achieving best performance. The performance of mixed CNT bundle and copper is then compared at local and global interconnects level at 22nm technology node. HSPICE simulations carried out using Berkeley predictive technology model (BPTM) at an operating frequency of 1GHz, shows that for interconnect length of 1000um, the mixed CNT and optimized CNT (CNT_Opt) bundles are 1.98X and 2.20X faster, 74% and 84% more energy efficient respectively than the Copper interconnects.
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Cartwright, Alexander. "Dynamic property rights and the market process". Journal of Entrepreneurship and Public Policy 5, n. 3 (7 novembre 2016): 273–84. http://dx.doi.org/10.1108/jepp-10-2015-0031.
Testo completoAbstract (sommario):
Purpose Clearly defined and enforceable property rights are commonly recognized as prerequisites to economic calculation and the market process. The purpose of this paper is to argue that when entrepreneurs add or subtract certain rights from the bundle of rights that constitute a property right they face a classic planner’s dilemma: the need to separate the technologically possible from the economically feasible. Traditionally, prices provide the signals needed to resolve the planners dilemma, but because prices refer to the entire bundle of rights that constitutes property, the entrepreneur is unable to immediately identify the combination of rights that isolates the attribute of a good consumers desire to purchase. Creating new bundles of property rights results in new prices, which generate new information essential to further developing economically viable arrangements of property rights; hence, property rights are dynamic. Design/methodology/approach The paper develops the theory of dynamic property rights, and then offers two case studies that illustrate different elements in the theory. One case study applies the theory to productive entrepreneurship, specifically in the sharing economy. The second case study applies the theory to protective entrepreneurship via a historical study of land title use in England and France. The author concludes with policy implications. Findings Recognizing that property rights are dynamic has several important implications. Restricting the bundling or de-bundling of property rights is a form of intervention in the market process equivalent to price fixing. Similarly, efforts to support property rights protecting institutions need to account for the fact that property rights bundles are not necessarily static but control over them needs to be stable and predictable. Finally, a more robust and accurate conceptualization of the marking process and what it means to “economize” on scarce resources does not just include the efficient allocation of property rights, but also the efficient allocation of the underlying rights bundles themselves. Social implications A dynamic theory of property rights allows the author to understand how property rights evolve and offer an account of different property rights regimes by highlight the living connection between productive and protective entrepreneurship. Originality/value This paper aims to integrate ideas from market process theory with entrepreneurship and institutional evolution. The paper extends the ideas in the UCLA property rights school to illuminate two case studies – one highly relevant to current policy makers, and the other relevant to development economists.
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Szada-Borzyszkowska, Monika Edyta, Wojciech Kacalak, Łukasz Bohdal e Wiesław Szada-Borzyszkowski. "Analysis and Basics of Improving the Process of Cutting Electrical Sheet Bundles with a High-Pressure Abrasive Water Jet". Materials 17, n. 7 (4 aprile 2024): 1666. http://dx.doi.org/10.3390/ma17071666.
Testo completoAbstract (sommario):
Electrical steels are widely used in the electrical industry in the construction of many devices, e.g., power transformer cores and distribution transformers. An important parameter of electrical components that determines the efficiency of devices is energy loss during remagnetization. These losses are influenced, among other factors, by steel cutting processes. The common techniques for cutting electrical materials on industrial lines are mechanical cutting and laser cutting. High-pressure abrasive water jet (AWJ) cutting, unlike the technologies mentioned above, can ensure higher quality of the cut edge and limit the negative impact of the cutting process on the magnetic properties of sheet metal. However, the correct control of the process and the conditions of its implementation comprise a complex issue and require extensive scientific research. This work presents a new approach to cutting electric sheets, involving bundle cutting, which significantly increases the processing efficiency and the dimensional and shape accuracy of the cut details. The tests were carried out for bundles composed of a maximum of 30 sheets, ready to be joined in a stator and rotor in a motor. The influence of processing conditions on the quality of the cut edges of sheet metal, the width of the deformation zone, and the burr height were analyzed. The detailed analysis of the quality of the cut edges of electrical bundled sheets creates new possibilities for controlling the AWJ cutting process in order to obtain a product with the desired functional and operational properties.
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Aanandha Saravanan, K., e Dr P. Suresh. "Prioritized scheduling scheme for critical and non-critical information packets". International Journal of Engineering & Technology 7, n. 3 (10 agosto 2018): 1705. http://dx.doi.org/10.14419/ijet.v7i3.13338.
Testo completoAbstract (sommario):
The process of energy saving mechanisms is been utilized by proper planning to transmit both critical clip and non-real infor-mation by reading overheads there by reducing throughput and bandwidth in large scale critical clip networks. The existing bundle sched-uling mythologies used were based on the First -in First-out (FIFO) manner in such cases the critical information at particular instant cannot be processed quickly but proposed system is designed in such a way it consists of three tier precedence structure .the critical in-formation bundles are placed in the higher status prioritizing queue and processed immediately and sent to the destination node where oth-er information bundles are given less precedence on the basis of position for non critical information bundles. The proposed scheme, ener-gy efficient in reducing the number of transmission by using merger technique. The lowest precedence bundles are processed after the higher precedence bundles. The proposed algorithm proves its uniqueness based on end -to-end delay than Energy efficient wake up scheduling MAC (EEWS) and Traffic Adaptive MAC protocol (TAMAC)
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Batthula, Vinay, Sanjana H. Somnath e Vikram Datta. "Reducing late-onset neonatal sepsis in very low birthweight neonates with central lines in a low-and-middle-income country setting". BMJ Open Quality 10, Suppl 1 (luglio 2021): e001353. http://dx.doi.org/10.1136/bmjoq-2021-001353.
Testo completoAbstract (sommario):
BackgroundLate-onset neonatal sepsis (LONS) is a significant contributor to morbidity and mortality in very low birthweight (VLBW) neonates with indwelling central lines. Compliance to central line care bundles is suboptimal in low-and-middle-income country settings. Point of care quality improvement (POCQI) method may be used to improve the compliance gap. We used the POCQI method to achieve an improvement in compliance to central line care bundles with an aim to reduce LONS in a subset of VLBW neonates.MethodsA pre and post-intervention study consisting of three phases was conducted in a tertiary care neonatal intensive care unit. A root-cause analysis was undertaken to find the causes of LONS in VLBW babies with central lines. Multiple change ideas were identified and tested using sequential Plan-Do-Study-Act (PDSA) cycles to address the issue of reduced compliance to the central line care bundles. The change ideas tested in PDSA cycles which were successful were adopted. Compliance to the insertion and maintenance bundles was measured as process indicators. LONS, central line associated bloodstream infections and all-cause mortality rates were measured as outcome indicators.ResultsA total of 10 PDSA cycles testing multiple change ideas (staff education, audio-visual aids, supply issues) were undertaken during the study duration. Bundles were not being used in the study setting prior to the initiation of the study. Insertion bundle compliance was above 90% and maintenance bundle compliance increased from 23.3% to 42.2% during the intervention and sustenance phases, respectively. A 43.3% statistically significant reduction in LONS rates was achieved at the end of the study. No effect on mortality was seen.ConclusionPOCQI method can be used to improve compliance to central line care bundles which can lead to a reduction of LONS in VLBW neonates with central lines in situ.
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Kaczmarczyk, J. "Numerical simulations of preliminary state of stress in bundles of metal sheets on the guillotine". Archives of Materials Science and Engineering 85, n. 1 (1 maggio 2017): 14–23. http://dx.doi.org/10.5604/01.3001.0010.1554.
Testo completoAbstract (sommario):
Purpose: The work is aimed at determination of the influence of selected technological parameters on the preliminary state of stress in bundles of metal sheets being compressed by the pressure beam and submitted to the cutting process on a guillotine. Design/methodology/approach: The numerical simulations concerning the preliminary state of stress in the bundle of sheets were conducted by means of the finite element method and the computer system MSC.Patran with the computational module MSC.Marc. The experimental studies concerning the influence of a force loading the pressure beam on the quality of metal sheets were carried out using scanning electron microscopy. Findings: Possibilities of finding the optimum cutting parameters to maximise the values of preliminary state of stress in the bundle of metal sheets subjected to cutting. Higher values of stresses in the bundle coming from loading the pressure beam on the one hand decrease the maximum values of cutting force and thereby facilitate the performance of the cutting process, however on the other hand too high values of stresses might damage the surface of the top sheet in a bundle. Research limitations/implications: The main task of the presented research concerns the reduction of the maximum force generated on a knife during the cutting process. It is possible by increasing the values of preliminary state of stress realized in practice by applying higher values of a force loading the pressure beam. The force should not be too high in order to avoid damaging of the top sheet in the bundle loading by the pressure beam. Practical implications: The appropriate selection of the cutting parameters on account of preliminary state of stress in the bundle of sheets is essential in terms of industrial economy. It enables reducing the amount of waste caused by defects in bundles of sheets and decreases wear of the cutting tool. The research has been conducted in order to reduce the number of randomly occurring defects during cutting of metal sheets on a guillotine. Originality/value: The results acquired from the research facilitate selection of the best parameter settings required for conducting the optimum cutting process on a guillotine. The optimum set of cutting parameters leads to the reduction of defects’ number occurring during the process.
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Hou, Guangfeng, Vianessa Ng, Chenhao Xu, Lu Zhang, Guangqi Zhang, Vesselin Shanov, David Mast, Wookyun Kim, Mark Schulz e Yijun Liu. "Multiscale Modeling of Carbon Nanotube Bundle Agglomeration inside a Gas Phase Pyrolysis Reactor". MRS Advances 2, n. 48 (2017): 2621–26. http://dx.doi.org/10.1557/adv.2017.371.
Testo completoAbstract (sommario):
ABSTRACTCarbon nanotube (CNT) sock formation is required for the continuous synthesis of CNT thread or sheet using the gas phase pyrolysis method. Nanometer diameter CNTs form and are carried along the reactor tube by gas flow. During the flow, the CNT stick to each other and form bundles of about 10-100 nm diameter. Coupling of the CNT bundles in the flow leads to the formation of a centimeter diameter CNT sock with a wall that is hundreds of nanometers thick. Understanding the multiscale phenomena of sock formation is vital for optimizing the CNT synthesis and manufacturing process. In this work, we present a multiscale model for the CNT bundle agglomeration inside a horizontal gas phase pyrolysis reactor. The interaction between CNT bundles was analyzed by representing the attraction forces between CNTs using a discrete phase modeling method. Flow in the synthesis reactor was studied using a computational fluid dynamics (CFD) technique with multiphase flow analysis. A model was proposed to represent the coupling between CNT bundles and the gas flow. The effect of different CNT bundles on the agglomeration phenomenon was analyzed. The modeling results were also compared with experimental observations.
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Jiraporn, Napatsorn, Alisara Rungnontarat Charinsarn e Michael Sheridan. "Sugar in disguise or healthy indulgence: A cross-cultural comparision of the perceptions of dietary vice/virtue bundles". Management & Marketing 11, n. 2 (1 luglio 2016): 410–30. http://dx.doi.org/10.1515/mmcks-2016-0006.
Testo completoAbstract (sommario):
AbstractConsumers often choose virtue food to attain health goals and vice food to achieve indulgence goals. However, food and beverage companies have begun to nullify the vice and virtue categories by bundling vice and virtue ingredients into a single item (e.g. Yogurt with Oreo topping). This research contrasts how consumers from Asian and Western cultures evaluate such vice/virtue food bundles. Building on the perceptual processes and regulatory focus literatures, two cross-cultural experiments using participants in Thailand and the U.S. shows that Westerners prefer virtue-heavy bundles to vice-heavy bundles while Asians show similar preference across both types of bundle. Process measures revealed that Asians perceive greater fit between vice and virtue components in the bundles than Westerners and this perceived fit mediates the effect of culture on their food choice. Study 2 reveals the boundary condition. Specifically, when regulatory focus was manipulated, the effect of culture is no longer significant. The findings provide managerial implications for food and beverage companies as well as contributions to consumer behavior literature.
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Xia, Shan Shan, Wen Cheng Jin, Wen Huang e Hong Yin Yang. "Strength Test of Parallel Carbon Fiber Bundle for Prestressed Bridge". Applied Mechanics and Materials 90-93 (settembre 2011): 994–98. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.994.
Testo completoAbstract (sommario):
Because of good mechanical properties of the fiber composites, the fiber bundles without the resin curing process and with the features of high modulus, high strength and good performance of creasing resistance etc, can be used in prestressed structures. According to the strength properties of the fiber, the tensile characteristic function of the fiber bundles is derived. The tensile test is designed and the parameters of the weibull distribution are estimated based on the result of the test. The ultimate strength of fiber is inversely proportional to the length of fiber. The calculating strength should be reduced in design, because the discreteness of the strength of the fiber bundle in test is much larger than the calculated values.
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Gogonin, Ivan, e Oleg Volodin. "Influence of the developing region of the thermal boundary layer on heat transfer during vapor condensation on horizontal tube bundles". E3S Web of Conferences 459 (2023): 05004. http://dx.doi.org/10.1051/e3sconf/202345905004.
Testo completoAbstract (sommario):
The purpose of this publication is to describe a phenomenon that is fundamentally important and, at the same time, hardly elucidated in the literature. In the process of film condensation of vapor on the bundles of horizontal tubes, a developing region of the thermal boundary layer is formed on each tube of the bundle; the role of this region in heat transfer is important, and in some cases decisive. The paper presents experimental results on the influence of various contributions of the developing region on heat transfer during film vapor condensation on tube bundles. Based on the data obtained, an algorithm for calculating a condenser during condensation of a stationary vapor without non-condensable impurities is proposed.
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Li, Xing, Hui Wang, Qianglong Wang, Jinrong Qiu e Sichao Tan. "Experimental study on Velocity Distribution in Rod Bundle Channels under Flow Fluctuation". Journal of Physics: Conference Series 2441, n. 1 (1 marzo 2023): 012061. http://dx.doi.org/10.1088/1742-6596/2441/1/012061.
Testo completoAbstract (sommario):
Abstract Thermal-hydraulic behaviors within a PWR fuel assembly is very complex under accident conditions and marine conditions, which has a significant impact on reactor safety. It is crucial to carry out studies on thermal-hydraulic properties under transient conditions. A telecentric lens and a pulse signal generator are applied to improve the performance of PIV system, a high temporal and spatial resolution measurement for flow fields in rod bundle channels is achieved, the velocity distribution in rod bundles are obtained under accelerating flows and decelerating flows. The steady-state flow field is measured to use as a reference, the effect of flow fluctuations on the flow fields in the rod bundle is analyzed. The results present, the accelerating flows improve the velocity gradient between adjacent flow layers in rod bundles and weaken the lateral velocity. In the contrary, the decelerating flows weaken the velocity gradient between flow layers in rod bundles and improve lateral velocity. Conversely, the velocity gradient attenuates in decelerating flows between the rod beam layers and increases the lateral velocity. During the accident, the thermal-hydraulic behavior in the reactor has the characteristics of transient complexity and uncertainty. Studying the flow and heat transfer characteristics of the reactor core fuel assembly under accident conditions can improve a understanding for the accident development process.