Recessions can have a cleansing effect by encouraging the reallocation of resources from low-productivity firms towards higher-productivity ones. Whether this effect actually occurs is still debated. ...We contribute to answering this question by providing new evidence. Using a survey of firms matched with administrative data, we trace out the Covid-19 recession’s effects across the productivity distribution. Higher-productivity firms are found to have been more successful at maintaining employment, but there was not a rise in exit amongst lower-productivity firms. In line with the theory that support policies offset the cleansing effect of recessions, high-productivity firms are also found to have been less likely to take up government support.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Functional Magnetic Resonance Imaging (fMRI) studies have become increasingly popular both with clinicians and researchers as they are capable of providing unique insights into brain functions. ...However, multiple technical considerations (ranging from specifics of paradigm design to imaging artifacts, complex protocol definition, and multitude of processing and methods of analysis, as well as intrinsic methodological limitations) must be considered and addressed in order to optimize fMRI analysis and to arrive at the most accurate and grounded interpretation of the data. In practice, the researcher/clinician must choose, from many available options, the most suitable software tool for each stage of the fMRI analysis pipeline. Herein we provide a straightforward guide designed to address, for each of the major stages, the techniques, and tools involved in the process. We have developed this guide both to help those new to the technique to overcome the most critical difficulties in its use, as well as to serve as a resource for the neuroimaging community.
Needle-based procedures are commonly performed during minimally invasive surgery for treatment and diagnosis. Accurate needle tip placement is important for the success of the procedures. ...Misplacement of the needle tip might cause unsuccessful treatment or misdiagnosis. Robot-assisted needle insertion systems have been developed in order to steer flexible bevel-tipped needles. However, current systems depend on the information of maximum needle curvature, which is estimated by performing prior insertions. This work presents a new three-dimensional flexible needle steering system which integrates an optimal steering control, ultrasound-based needle tracking system, needle deflection model, online needle curvature estimation and offline curvature estimation based on biomechanics properties. The online and the offline curvature estimations are used to update the steering control in real time. The system is evaluated by experiments in gelatin phantoms and biological tissues (chicken breast tissues). The average targeting error in gelatin phantoms is 0.42 ± 0.17 mm, and in biological tissues is 1.63 ± 0.29 mm. The system is able to accurately steer a flexible needle in multi-layer phantoms and biological tissues without performing prior insertions to estimate the maximum needle curvature.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•A crack tip monitoring is studied through multiscale contactless optical methods.•DIC and ESPI techniques are employed to measure the experimental data.•The crack is detected and its length is ...measured by both methods.•SIF is calculated and compared to the reference solution.•The crack opening evolution is studied by ESPI and DIC analyses.
This study focuses on the development of a complementary fatigue crack-tip evaluation approach with multiscale optical techniques with different resolutions. A middle tension (MT) specimen, of aluminium alloy AA6082-T6, was prepared and submitted to a cyclic fatigue loading to generate a fatigue crack. Then, it was statically loaded under a uniaxial tensile condition, and two non-contact full-field optical techniques, Digital Image Correlation (DIC) and Electronic Speckle Pattern Interferometry (ESPI), were employed to acquire the experimental data. While the specimen is loaded with incremental force values, the behaviour of the cracked area is monitored, with displacement and deformation fields acquired for each force increment. The obtained data is thereby used to calculate the Stress Intensity Factor (SIF) and monitor the crack opening evolution. An overdeterministic algorithm was developed for the SIF determination. The main contribution of the present work is the development of a complementary multiscale methodology, which employs available techniques with different resolutions to monitor the tip of a fatigue crack, drawing a comparison between calculated parameters for each system to shift from one technique to the higher resolution one and validating the proposed methodologies. The obtained SIF values are compared to the reference solution proposed by ASTM E647, and an acceptable agreement has been verified amongst the results.
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A timeless critique holds that the radical is animated by a deep sense of certainty that leads to the worst excesses. By distinguishing essentialist and non-essentialist forms of radicalism, Ernesto ...Laclau offers a "coalitional" form of radicalism that, in effect, responds to this critique. Laclau deconstructs classical forms of radicalism, such as Marxism, to show how one can use some of their formal components, such as dichotomic rhetoric and a notion of utopia, without assuming that their particular content (e.g., the figure of the proletarian or the socialist utopia) entails the permanent abolition of oppression. Laclau's radicalism enables political actors to build their own radical front by politicizing and creating linkages between issues. Laclau thus avoids the epistemic certainty of classical radicalisms. However, in the interest of politically effective radicalism, he deploys a localized form of certainty that has an ambivalent potential for intolerance and violence.
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) is a gram-negative bacterium that infects approximately 4.4 billion individuals worldwide. However, its prevalence varies among different geographic areas, and is influenced by several factors. ...The infection can be acquired by means of oral-oral or fecal-oral transmission, and the pathogen possesses various mechanisms that improve its capacity of mobility, adherence and manipulation of the gastric microenvironment, making possible the colonization of an organ with a highly acidic lumen. In addition,
presents a large variety of virulence factors that improve its pathogenicity, of which we highlight cytotoxin associated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and gamma-glutamyl transpeptidase. The host immune system, mainly by means of a Th1-polarized response, also plays a crucial role in the infection course. Although most
-positive individuals remain asymptomatic, the infection predisposes the development of various clinical conditions as peptic ulcers, gastric adenocarcinomas and mucosa-associated lymphoid tissue lymphomas. Invasive and non-invasive diagnostic methods, each of them with their related advantages and limitations, have been applied in
detection. Moreover, bacterial resistance to antimicrobial therapy is a major challenge in the treatment of this infection, and new therapy alternatives are being tested to improve
eradication. Last but not least, the development of effective vaccines against
infection have been the aim of several research studies.
Coffee is the most widely consumed source of caffeine worldwide, partly due to the psychoactive effects of this methylxanthine. Interestingly, the effects of its chronic consumption on the brain's ...intrinsic functional networks are still largely unknown. This study provides the first extended characterization of the effects of chronic coffee consumption on human brain networks. Subjects were recruited and divided into two groups: habitual coffee drinkers (CD) and non-coffee drinkers (NCD). Resting-state functional magnetic resonance imaging (fMRI) was acquired in these volunteers who were also assessed regarding stress, anxiety, and depression scores. In the neuroimaging evaluation, the CD group showed decreased functional connectivity in the somatosensory and limbic networks during resting state as assessed with independent component analysis. The CD group also showed decreased functional connectivity in a network comprising subcortical and posterior brain regions associated with somatosensory, motor, and emotional processing as assessed with network-based statistics; moreover, CD displayed longer lifetime of a functional network involving subcortical regions, the visual network and the cerebellum. Importantly, all these differences were dependent on the frequency of caffeine consumption, and were reproduced after NCD drank coffee. CD showed higher stress levels than NCD, and although no other group effects were observed in this psychological assessment, increased frequency of caffeine consumption was also associated with increased anxiety in males. In conclusion, higher consumption of coffee and caffeinated products has an impact in brain functional connectivity at rest with implications in emotionality, alertness, and readiness to action.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The concepts of "radicalism" and "extremism" have been the focus of increasing scholarly attention in recent years, but, surprisingly, there has not been the same kind of effort to specify their ...opposites, such as the concept of "moderation." In this article I argue that because "radicalism" and "extremism" have been defined in generally negative terms, we may deepen and refine our understanding of moderation once we are equipped with a more neutral conception of radicalism. Accordingly, I propose a new approach to the study of radical ideologies by comparing them to literary genres. Just as literary genres use tropes that constrain our reading of a text, radical ideologies use tropes-as, for example, the Marxists' use of "reactionary" or "bourgeois"-that refer to a much wider background dichotomy, on which they base their arguments to discredit those of their opponents or to reinforce those of their supporters. Using this approach, I show how the Marxist theorist and leading German politician Eduard Bernstein (1850-1932)-one of the founders of modern Social Democracy-made a step-by-step critique of the Social Democratic Party's orthodox Marxist tropes and core narrative that thoroughly undermined their arguments. Bernstein, I further suggest, was a particularly good example of a political moderate because he did not altogether reject the claims of his radical Marxist opponents but rather accepted those parts of their reasoning that he considered valid. By thus opening the way for constructing an anti-radical Marxist narrative, Bernstein's example shows how moderates can "steal a page" from the radicals' playbook to create alternative narratives whose central opponents are the radicals themselves. I conclude by briefly discussing two contemporary thinkers-Norberto Bobbio and Karl Popper-who went further than Bernstein in the development of a fully fleshed anti-radical narrative.
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•A coupled 3D laser scanning and DIC system was innovated.•3D tunnel model tunnel profile was obtained by the system.•Geometry acquisition and deformation monitoring of runnels were accomplished.•3D ...DIC was adopted to monitor the geometrical changes.
In this study, a 40 m-long section of a shallow railway rock tunnel so-called “Monte Seco tunnel” located at Vitoria Minas Railway in Brazil is investigated. In the real environment, the tunnel has been scanned by a 3D Terrestrial Laser Scanning (TLS) instrumentation and its geometry was reconstructed on a point cloud. Due to the complex geometry of the irregular rock face created by drill and blast, the obtained geometry lacked a number of regions (occlusions). In this study, a small-size model of the obtained point cloud was built through additive manufacturing and submitted to laboratory tests. A scaled demonstrator was developed for the acquisition of the 3D tunnel model profile with a Laser Scanning System (LSS), comprising a camera and a circular laser that scans the entire tunnel surface. After 3D geometry acquisition, the tunnel model was compressively loaded by imposing a displacement from the exterior wall and the deformation was monitored by a 3D Digital Image correlation (DIC) system setup adapted to the rail structure. Promising results have been accomplished and the achieved tunnel’s point cloud verified the geometrical characteristics with minimum occlusions. Owing to obtained successful results on the geometry documentation, a real-scale 3D LSS model is presented for operation in a real environment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Previous studies have shown an association between cognitive decline and white matter integrity in aging. This led to the formulation of a "disconnection hypothesis" in the aging-brain, which states ...that the disruption in cortical network communication may explain the cognitive decline during aging. Although some longitudinal studies have already investigated the changes occurring in white matter microstructure, most focused on specific white matter tracts. Our study aims to characterize the longitudinal whole-brain signatures of white matter microstructural change during aging. Furthermore, we assessed the relationship between distinct longitudinal alterations in white matter integrity and cognition. White matter microstructural properties were estimated from diffusion magnetic resonance imaging, and cognitive status characterized from extensive neurocognitive testing. The same individuals were evaluated at two timepoints, with a mean interval time of 52.8 months (SD = 7.24) between first and last assessment. Our results show that age is associated with a decline in cognitive performance and a degradation in white matter integrity. Additionally, significant associations were found between diffusion measures and different cognitive dimensions (memory, executive function and general cognition). Overall, these results suggest that age-related cognitive decline is related to white matter alterations, and thus give support to the "disconnected hypothesis" of the aging brain.
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