bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved cosmological constraints on the neutrino mass and lifetime
Authors: Abellán Guillermo Franco , Chacko Zackaria , Dev Abhish , Du Peizhi , Poulin Vivian , Tsai Yuhsin
Published: August 2022

Abstract

We present cosmological constraints on the sum of neutrino masses as a function of the neutrino lifetime, in a framework in which neutrinos decay into dark radiation after becoming non-relativistic. We find that in this regime the cosmic microwave background (CMB), baryonic acoustic oscillations (BAO) and (uncalibrated) luminosity distance to supernovae from the Pantheon catalog constrain the sum of neutrino masses ∑mν to obey ∑mν< 0.42 eV at (95% C.L.). While the bound has improved significantly as compared to the limits on the same scenario from Planck 2015, it still represents a significant relaxation of the constraints as compared to the stable neutrino case. We show that most of the improvement can be traced to the more precise measurements of low-ℓ polarization data in Planck 2018, which leads to tighter constraints on τreio (and thereby on As), breaking the degeneracy arising from the effect of (large) neutrino masses on the amplitude of the CMB power spectrum.
CD69-oxLDL ligand engagement induces Programmed Cell Death 1 (PD-1) expression in human CD4 + T lymphocytes
Authors: Jiménez-Fernández María , Rodríguez-Sinovas Cristina , Cañes Laia , Ballester-Servera Carme , Vara Alicia , Requena Silvia , de la Fuente Hortensia , Martínez-González José , Sánchez-Madrid Francisco
Published: August 2022

The mechanisms that control the inflammatory–immune response play a key role in tissue remodelling in cardiovascular diseases. T cell activation receptor CD69 binds to oxidized low-density lipoprotein (oxLDL), inducing the expression of anti-inflammatory NR4A nuclear receptors and modulating inflammation in atherosclerosis. To understand the downstream T cell responses triggered by the CD69-oxLDL binding, we incubated CD69-expressing Jurkat T cells with oxLDL. RNA sequencing revealed a differential gene expression profile dependent on the presence of CD69 and the degree of LDL oxidation. CD69-oxLDL binding induced the expression of NR4A receptors (NR4A1 and NR4A3), but also of PD-1. These results were confirmed using oxLDL and a monoclonal antibody against CD69 in CD69-expressing Jurkat and primary CD4 + lymphocytes. CD69-mediated induction of PD-1 and NR4A3 was dependent on NFAT activation. Silencing NR4A3 slightly increased PD-1 levels, suggesting a potential regulation of PD-1 by this receptor. Moreover, expression of PD-1, CD69 and NR4A3 was increased in human arteries with chronic inflammation compared to healthy controls, with a strong correlation between PD-1 and CD69 mRNA expression (r = 0.655 P < 0.0001). Moreover, PD-1 was expressed in areas enriched in CD3 infiltrating T cells. Our results underscore a novel mechanism of PD-1 induction independent of TCR signalling that might contribute to the role of CD69 in the modulation of inflammation and vascular remodelling in cardiovascular diseases.
Perverse Sheaves with Nilpotent Singular Support on the Stack of Coherent Sheaves on an Elliptic Curve
Authors: Hennecart Lucien
Published: August 2022

We define a stratification of the moduli stack of coherent sheaves on an elliptic curve which allows us (1) to give an explicit description of the irreducible components of the global nilpotent cone of elliptic curves, (2) to establish an explicit bijection between the simple objects of the category of perverse sheaves defined by Schiffmann to categorify the elliptic Hall algebra (the so-called spherical Eisenstein sheaves) and the irreducible components of the global nilpotent cone and (3) to give an explicit description and parametrization of the perverse sheaves on the moduli stack of coherent sheaves on an elliptic curve having nilpotent singular support. Along the way, we find a combinatorial parametrization of the irreducible components of the semistable locus of the elliptic global nilpotent cone. The comparison with Bozec’s parametrization leads to an interesting combinatorial problem.
Some Subcritical Estimates for the $$\ell ^p$$-Improving Problem for Discrete Curves
Authors: Dendrinos Spyridon , Hughes Kevin , Vitturi Marco
Published: August 2022

We apply Christ’s method of refinements to the $$\ell ^p$$

ℓ
p

-improving problem for discrete averages $${\mathcal {A}}_N$$

A
N

along polynomial curves in $${\mathbb {Z}}^d$$

Z

d

. Combined with certain elementary estimates for the number of solutions to certain special systems of diophantine equations, we obtain some restricted weak-type $$p \rightarrow p'$$

p
→

p
′

estimates for the averages $${\mathcal {A}}_N$$

A
N

in the subcritical regime. The dependence on N of the constants here obtained is sharp, except maybe for an $$\epsilon $$
ϵ
-loss.
Surgical hip dislocation with relative femoral neck lengthening and retinacular soft-tissue flap for sequela of Legg–Calve–Perthes disease
Authors: Leibold Christiane Sylvia , Vuillemin Nicolas , Büchler Lorenz , Siebenrock Klaus Arno , Steppacher Simon Damian
Published: August 2022

Objective

Correction of post-LCP (Legg–Calve–Perthes) morphology using surgical hip dislocation with retinacular flap and relative femoral neck lengthening for impingent correction reduces the risk of early arthritis and improves the survival of the native hip joint.

Indications

Typical post-LCP deformity with external and internal hip impingement due to aspherical enlarged femoral head and shortened femoral neck with high riding trochanter major without advanced osteoarthritis (Tönnis classification ≤ 1) in the younger patient (age < 50 years).

Contraindications

Advanced global osteoarthritis (Tönnis classification ≥ 2).

Surgical technique

By performing surgical hip dislocation, full access to the hip joint is gained which allows intra-articular corrections like cartilage and labral repair. Relative femoral neck lengthening involves osteotomy and distalization of the greater trochanter with reduction of the base of the femoral neck, while maintaining vascular perfusion of the femoral head by creation of a retinacular soft-tissue flap.

Postoperative management

Immediate postoperative mobilization on a passive motion device to prevent capsular adhesions. Patients mobilized with partial weight bearing of 15 kg with the use of crutches for at least 8 weeks.

Results

In all, 81 hips with symptomatic deformity of the femoral head after healed LCP disease were treated with surgical hip dislocation and offset correction between 1997 and 2020. The mean age at operation was 23 years; mean follow-up was 9 years; 11 hips were converted to total hip arthroplasty and 1 patient died 1 year after the operation. The other 67 hips showed no or minor progression of arthrosis. Complications were 2 subluxations due to instability and 1 pseudarthrosis of the lesser trochanter; no hip developed avascular necrosis.
Design, modeling, and control of a variable stiffness elbow joint
Authors: Baggetta Mario , Berselli Giovanni , Palli Gianluca , Melchiorri Claudio
Published: August 2022

New technological advances are changing the way robotics are designed for safe and dependable physical human–robot interaction and human-like prosthesis. Outstanding examples are the adoption of soft covers, compliant transmission elements, and motion control laws that allow compliant behavior in the event of collisions while preserving accuracy and performance during motion in free space. In this scenario, there is growing interest in variable stiffness actuators (VSAs). Herein, we present a new design of an anthropomorphic elbow VSA based on an architecture we developed previously. A robust dynamic feedback linearization algorithm is used to achieve simultaneous control of the output link position and stiffness. This actuation system makes use of two compliant transmission elements, characterized by a nonlinear relation between deflection and applied torque. Static feedback control algorithms have been proposed in literature considering purely elastic transmission; however, viscoelasticity is often observed in practice. This phenomenon may harm the performance of static feedback linearization algorithms, particularly in the case of trajectory tracking. To overcome this limitation, we propose a dynamic feedback linearization algorithm that explicitly considers the viscoelasticity of the transmission elements, and validate it through simulations and experimental studies. The results are compared with the static feedback case to showcase the improvement in trajectory tracking, even in the case of parameter uncertainty.
Estimating policy-corrected long-term and short-term tax elasticities for the USA, Germany, and the United Kingdom
Authors: Hayo Bernd , Mierzwa Sascha , Ünal Umut
Published: August 2022

We estimate the elasticities of the most important tax categories using a new quarterly database of discretionary tax measures for the USA, Germany, and the United Kingdom over the period 1980Q1 to 2018Q2. Employing Romer and Romer’s (2009) narrative approach, we construct a policy-neutral dataset based on revenue figures from governmental records. Using this quantitative information, we are able to subtract policy-induced changes, which often are not considered in the literature. Furthermore, we estimate state-dependent elasticities. Our conclusions are as follows. (i) In Germany and the UK, long-term tax-to-base elasticities are generally higher than short-term elasticities, whereas results for the USA are mixed. (ii) Short-term base-to-output elasticities tend to be smaller than unity, whereas long-term elasticities are close to unity. (iii) German and UK tax-to-output elasticities in the short term are lower than long-term elasticities, with mixed results for the USA. (iv) For tax-to-base elasticities, we find business-cycle asymmetries across countries but not within countries. (v) For base-to-output elasticities, our results suggest few asymmetries across countries and more asymmetries across tax types. (vi) Typically, the above conclusions do not hold for corporate income tax.
Dual labor market and the “Phillips curve puzzle”: the Japanese experience
Authors: Aoyama Hideaki , Di Guilmi Corrado , Fujiwara Yoshi , Yoshikawa Hiroshi
Published: August 2022

Low inflation was once welcomed by both policymakers and the public. However, Japan’s experience during the 1990s changed the consensus of economists and central banks around the world regarding prices. Facing deflation and the zero-interest bound at the same time, the Bank of Japan had difficulty conducting an effective monetary policy, making Japan’s stagnation unusually prolonged. The too-low inflation that concerns central banks today translates into the “Phillips curve puzzle.” In the United States and Japan, in the course of the recovery from the Great Recession after the 2008 Global Financial Crisis, the unemployment rate had steadily declined to a level commonly regarded as lower than the natural rate or NAIRU. However, inflation remained low. In this paper, we consider a minimal model of the dual labor market to jointly investigate how the different factors affecting the structural evolution of the labor market have contributed to the observed flattening of the Phillips curve. We find that the level of bargaining power of workers, elasticity of the supply of labor to wage in the secondary market, and composition of the workforce are the main factors jointly explaining the evidence for Japan.
Age-related asymmetry in anticipatory postural movements during unilateral arm movement and imagery
Authors: Wider Chloe , Mitra Suvobrata , Boulton Hayley , Andrews Mark
Published: August 2022

Reaching movements of the arms are accompanied by anticipatory (APM) and compensatory postural motion (CPM) that counteract the resulting perturbations to body stability. Recent research has shown that these postural actions are also observable in the context of imagined arm movements. As motor imagery (MI) shares many neurophysiological and behavioral characteristics with physical movements, and MI training can affect subsequent performance, MI tasks provide a good setting for studying the anticipatory aspects of postural control. This study investigated APMs and CPMs of the head and hip of healthy young and older adults in the temporal vicinity of physical and imagined forward raises of the dominant and non-dominant arm. When MI of the dominant arm was self-initiated, both age groups showed APM in the anteroposterior plane. When the self-initiated MI was of the non-dominant arm, only the older group showed anteroposterior APM. The older group did not show APM when an expected arm movement (or MI) was made to an external signal. This suggests an age-related deficit in coordinating postural preparation with external events. Only the older group showed mediolateral APM, and only for dominant arm MI, indicating sensitivity to potential perturbation to the weaker, non-dominant side of the body. Overall, the older group showed more anticipatory postural motion at the head. Systematic APM for manual MI suggests that MI training may be an effective intervention for anticipatory postural control. An integrated model of postural support for executed and imagined limb movements is suggested.
Surface evolution of crystalline SrTiO3, LaAlO3 and Y3Al5O12 targets during pulsed laser ablation
Authors: Jung Florian , Delmdahl Ralph , Heymann Andreas , Fischer Max , Karl Helmut
Published: August 2022

Pulsed laser ablation and deposition find applications in various technological and scientific fields, where precise control of the laser target interaction is crucial for achieving reproducible results. In this work, we investigated pulsed laser ablation of single crystalline (001), (011) and (111) oriented SrTiO3 (STO), (102) LaAlO3 (LAO) and (001) Y3Al5O12 (YAG) targets. The morphology, oxygen loss, and crack formation on the target surfaces after irradiation with a series of KrF excimer laser pulses will be discussed. The target surface morphology was imaged by atomic force, scanning electron microscopy and confocal laser scanning microscopy. Electron backscatter diffraction analysis and energy-dispersive X-ray spectroscopy were used to analyze the crystallographic changes of the surface and the elemental composition. The target material STO shows a significant crack formation and layer separation increasing with surface crystal orientation from (001) through (011) to (111) and laser pulse fluence. In contrast, the laser-ablated surfaces of LAO show only thin hairline cracks and YAG stays free of cracks in the whole laser fluence range investigated but presents large chipped areas.
Multipitched plasmonic nanoparticle grating for broadband light enhancement in white light-emitting organic diodes
Authors: Auer-Berger Manuel , Tretnak Veronika , Sommer Christian , Wenzl Franz-Peter , Krenn Joachim R. , List-Kratochvil Emil J. W.
Published: August 2022

We apply regular arrays of plasmonic nanodisks to enhance light emission from an organic white light-emitting diode (WOLED). To achieve broadband enhancement, we apply, first, aluminum as a nanodisk material with moderate loss throughout the whole visible spectral range. Second, broadband light coupling is mediated by surface lattice resonances from a multipitch array built from two superimposed gratings with different grating constants formed by elliptic and circular nanodisks. To demonstrate the viability of this concept, the grating structure was embedded in the hole transport layer of a solution-processed phosphorescent WOLED exhibiting a current efficiency of 2.1 cd/A at 1000 cd/m2. The surface lattice resonances in the grating raise the current efficiency of the device by 23% to 2.6 cd/A at 1000 cd/m2, while the device emission changes from a neutral white to a warm white appearance with CIE1931 (x,y) coordinates of (0.361, 0.352) and (0.404, 0.351), respectively. The WOLED was characterized in detail optically by extinction and angle-resolved photoluminescence and as well by electroluminescence measurements for its opto-electronic characteristics. The experimental results agree well with finite-difference time domain simulations that aim at a better understanding of the underlying physical mechanisms. In summary, our work presents a novel versatile approach for achieving broadband enhancement of light emission in WOLEDs over a wide spectral range.
Distribution of energy and macronutrient intakes across eating occasions in European children from 3 to 8 years of age: The EU Childhood Obesity Project Study
Authors: Jaeger Vanessa , Koletzko Berthold , Luque Veronica , Ferré Natàlia , Gruszfeld Dariusz , Gradowska Kinga , Verduci Elvira , Zuccotti Gian Vincenzo , Xhonneux Annick , Poncelet Pascale , Grote Veit
Published: August 2022

Purpose

We aimed to characterize the distribution of energy and macronutrient intakes across eating occasions (EO) in European children from preschool to school age.

Methods

Data from 3-day weighed food records were collected from children at ages 3, 4, 5, 6 and 8 years from Belgium, Germany, Italy, Poland and Spain. Food intakes were assigned to EO based on country-specific daytimes for breakfast, lunch, supper and snacks (morning, afternoon). The average energy and nutrient intakes were expressed as percentage of total energy intake (%E). Nutrients were additionally expressed as percentage per EO (%EEO). Foods were assigned to food groups; variation in intake was calculated via coefficient of variation (CV). We analyzed age trends in diurnal intake using mixed-effects beta regression.

Results

The 740 healthy children included in the analysis consumed the largest proportion of daily energy at lunch (31%E ± 8, M ± SD) and supper (26%E ± 8), followed by breakfast (19%E ± 7) and snacks [afternoon (16%E ± 8); morning (8%E ± 7)], with the most variable intake at morning snack (CV = 0.9). The nutrient composition at lunch and supper was highest for fat (36 ± 9%ELunch; 39 ± 11%ESupper) and protein (18 ± 5%ELunch; 18 ± 6%ESupper) and at breakfast and snacks for carbohydrates (54 ± 12%EBreakfast; 62 ± 12%ESnacks). High-sugar content foods were consumed in relatively large proportions at breakfast and snacks. Food intakes varied significantly with age, with lower snack intakes at later ages (p < 0.001).

Conclusion

Possibly unhealthy EOs with high-fat intakes and high-sugar-content foods were observed. Changes in nutrient composition of EOs may be beneficial for health.

Trial registry: ClinicalTrials.gov: NCT00338689; 19/June/2006.
Less improvement in knee function and higher rates of dissatisfaction in the short-term following total knee arthroplasty in people with mild radiographic arthritis
Authors: Khatib Yasser , Xia Andrew , Liu Rui , Naylor Justine M. , Harris Ian A.
Published: August 2022

Introduction

The purpose of this study was to assess if severity of radiographic changes of knee arthritis was associated with patient improvement after total knee arthroplasty (TKA). We hypothesised that patients with mild arthritis were more likely to report lower satisfaction, improvement in knee function and Oxford knee score (OKS) compared to patients with moderate or severe arthritis.

Materials and methods

Secondary analysis of prospectively collected data from TKA patients of two arthroplasty centres with knee radiographs available for assessment of disease severity. Patients completed the Oxford knee score (OKS) and were asked to rate the global improvement in knee condition and their satisfaction at 6 months post-TKA. Bivariable analysis and multivariable regression models were used to test the association between disease severity and each outcome.

Results

2226 patients underwent primary TKA and 3.6% had mild arthritis. Mean OKS improved from 17.0 (SD 18.0) to 38.0 (SD 8.1) 6 months after TKA. Two hundred and twenty-two patients (10%) reported ‘Poor’ or ‘Fair’ satisfaction, and 173 (8%) reported knee function was ‘Much worse’, ‘A little worse’ or ‘About the same’ 6 months post-TKA. Patients with mild arthritis showed improvement in OKS [mean improvement in OKS = 19 (SD 15)], but were significantly more likely to report dissatisfaction (OR = 3.10, 95% CI 1.62 to 5.91, p = 0.006), lack of improvement (OR = 4.49, 95% CI 2.38 to 8.47, p < 0.001) and lower OKS scores (− 3 points, 95% CI − 5.39 to − 0.85, p = 0.008) compared to patients with moderate to severe arthritis.

Conclusions

While patients with mild radiographic arthritic changes improve after TKA, they were significantly more likely to report higher rates of dissatisfaction, less improvement in knee function and OKS compared to patients with moderate-severe grades of arthritis.
Anticancer bioactivity of zerumbone on pediatric rhabdomyosarcoma cells
Authors: Urla Cristian , Stagno Matias Julian , Fuchs Jörg , Warmann Steven W. , Schmid Evi
Published: August 2022

Purpose

Natural products are generally regarded as safe and have been shown to mediate anticancer activities against a variety of cell types. Zerumbone is a natural cyclic sesquiterpene derived from the rhizome of Zingiber zerumbet, which has attracted extensive attention in the recent decade for anticancer activities. The present study investigates the in vitro effect of zerumbone on rhabdomyosarcoma cells.

Methods

Two rhabdomyosarcoma cell lines (RD and RH30) were used as the model system. The growth inhibition of zerumbone was measured by MTT-assay, apoptosis via flow cytometry, gene expression by real-time PCR, the migration by transwell assay, and intracellular signaling by Western blotting.

Results

Zerumbone shows anticancer effects on RD and RH30 cells in a dose-dependent manner via cell growth inhibition and induction of apoptosis. Exposure of RD and RH30 cells on zerumbone also resulted in a decrease of migration and downregulation of the hedgehog pathway.

Conclusions

Taken together, our study provided the first evidence that zerumbone imparted strong inhibitory and apoptotic effects on pediatric rhabdomyosarcoma cell lines and merit further investigation as a promising candidate for the anticancer therapy.
Geothermie-Großprojekte im ländlich-peripheren Kenia: Chancen und Herausforderungen zwischen Stromerzeugung für den nationalen Markt und regionaler Entwicklung durch direct use
Authors: Klagge Britta
Published: August 2022

Der zunehmende Einsatz erneuerbarer Energien geht mit einer grundlegenden Transformation bestehender Energiesysteme einher. Die damit verbundenen Umstrukturierungen an den Kraftwerkstandorten sind häufig konflikthaft, bergen aber auch Chancen für die Regionalentwicklung vor Ort. Dies gilt nicht nur für Deutschland, sondern auch in Kenia und allgemeiner Subsahara-Afrika. Besonders spannend sind in dieser Region aktuell Geothermie-Großprojekte, da sie neben der Stromerzeugung für das nationale Netz auch Möglichkeiten der direkten Nutzung (direct use) von Dampf bzw. heißem Wasser vor Ort bieten. Ein wichtiges Pionierland dafür ist Island, wo außer Gebäudeheizungen auch gewerbliche Prozesse mit geothermischer Wärme bzw. Dampf betrieben werden. Hierzu gehören neben Gemüseanbau in Gewächshäusern und Fischzucht in Aquakulturteichen die Produktion von Bier, Speiseeis und Algen sowie weitere gewerbliche Prozesse.

Für Kenia ist Island ein wichtiges Referenzland, da viele kenianische Geothermie-Expert:innen dort aus- und weitergebildet werden. Tatsächlich werden in Kenia bereits verschiedene Formen direkter geothermischer Nutzung erprobt. Neben dem bereits länger etablierten Blumenanbau und einem Spa sind dies Pilotprojekte mit Milch-Pasteurisierung, Gemüseanbau in Gewächshäusern, einer Wäscherei, Aquakulturteichen und Getreidetrocknung. Diese sowie weitere angedachte Nutzungen könnten insbesondere für Kenias ländlich-peripheren Norden, wo in großem Maßstab geothermische Ressourcen erschlossen werden (sollen), Chancen zur wirtschaftlichen Entwicklung bieten. Bisher sind dort viele Haushalte nicht ans nationale Stromnetz angeschlossen, und außerhalb der wenigen Städte leben die Menschen oft von mobiler Viehhaltung, ergänzt durch marginalen Ackerbau. Vor diesem Hintergrund und mit Fokus auf die Entwicklung der kenianischen Stromerzeugung und Geothermie-Projekte in Menengai und Baringo-Silali diskutiert der Beitrag die sich daraus ergebenden Chancen und Herausforderungen für die lokale wirtschaftliche Entwicklung.
Review: Urban groundwater issues and resource management, and their roles in the resilience of cities
Authors: La Vigna Francesco
Published: August 2022

The relationships between cities and underlying groundwater are reviewed, with the aim to highlight the importance of urban groundwater resources in terms of city resilience value. Examples of more than 70 cities worldwide are cited along with details of their groundwater-related issues, specific experiences, and settings. The groundwater-related issues are summarized, and a first groundwater-city classification is proposed in order to facilitate a more effective city-to-city comparison with respect to, for example, the best practices and solutions that have been put in practice by similar cities in terms of local groundwater resources management. The interdependences between some groundwater services and the cascading effects on city life in cases of shock (e.g., drought, heavy rain, pollution, energy demand) and chronic stress (e.g., climate change) are analyzed, and the ideal groundwater-resilient-city characteristics are proposed. The paper concludes that groundwater is a crucial resource for planning sustainability in every city and for implementing city resilience strategies from the climate change perspective.
Comparison of leaf litter decomposition and microbial decomposer communities in fringe and riverine mangroves in French Guiana
Authors: Dhaou Dounia , Gros Raphaël , Baldy Virginie , Adotévi Adoudé , Gaboriau Maeva , Estevez Yannick , Lecareux Caroline , Dupouyet Sylvie , Fernandez Catherine , Bousquet-Mélou Anne
Published: August 2022

Mangroves are highly productive and changing forests located in the intertidal zone of tropical regions. Leaf litter decomposition represents a substantial part of their carbon sink abilities. Little is known about the potential effect of climate change on this key process of ecosystem functioning. This study compared leaf litter microbial decay between fringe and riverineAvicennia germinansstands. A direct and reciprocal transplant experiment using litterbags was setup in French Guiana to test 3 hypotheses: (i) the activities and abundance of microbial decomposers are lowest in the fringe mangroves due to exposure to saline water and tidal immersion; (ii) for these reasons, litter decomposes faster in riverine stands; and (iii) according to the home-field advantage hypothesis, litter decomposes more rapidly in the environment from which it originates. Remaining litter masses, abundance of litter microbial community (phospholipid fatty acid signatures (PLFA)), and their functional capability (enzyme activities and Biolog) were assessed. Litter directly transplanted in riverine stands showed higher enzymatic activity (+ 77%), catabolic diversity (+ 10%), and microbial biomass (+ 60%) than litter transplanted directly in fringe stands. In contrast, both riverine and fringe derived litter showed faster decay at the fringe (14% mass loss) than riverine site (4% mass loss) between 30 and 45 days. Here, environmental conditions associated with different distances from the sea such as salinity and inundation regimes, rather than microbial features are suggested as main factors affecting decomposition process. Expected sea level rise in the coastal Guianas may therefore modify the mangroves productivity in the coming decades.
A self-interpretable module for deep image classification on small data
Authors: La Rosa Biagio , Capobianco Roberto , Nardi Daniele
Published: August 2022

Deep neural networks are the driving force of the recent explosion of machine learning applications in everyday life. However, they usually require a lot of training data to work well, and they act as black-boxes, making predictions without any explanation about them. This paper presents Memory Wrap, a module (i.e, a set of layers) that can be added to deep learning models to improve their performance and interpretability in settings where few data are available. Memory Wrap adopts a sparse content-attention mechanism between the input and some memories of past training samples. We show that adding Memory Wrap to standard deep neural networks improves their performance when they learn from a limited set of data, and allows them to reach comparable performance when they learn from the full dataset. We discuss how the analysis of its structure and content-attention weights helps to get insights about its decision process and makes their predictions more interpretable, compared to the same networks without Memory Wrap. We test our approach on image classification tasks using several networks on three different datasets, namely CIFAR10, SVHN, and CINIC10.
A hybrid adversarial training for deep learning model and denoising network resistant to adversarial examples
Authors: Ryu Gwonsang , Choi Daeseon
Published: August 2022

Deep neural networks (DNNs) are vulnerable to adversarial attacks that generate adversarial examples by adding small perturbations to the clean images. To combat adversarial attacks, the two main defense methods used are denoising and adversarial training. However, both methods result in the DNN having lower classification accuracy for clean images than conventionally trained DNN models. To overcome this problem, we propose a hybrid adversarial training (HAT) method that trains the denoising network and DNN model simultaneously. The proposed HAT method uses both clean images and adversarial examples denoised by the denoising network and non-denoised clean images and adversarial examples to train the DNN model. The results of experiments conducted on the MNIST, CIFAR-10, CIFAR-100, and GTSRB datasets show that the HAT method results in a higher classification accuracy than both conventional training with a denoising network and previous adversarial training methods. They also indicate that training with the HAT method results in average improvements in robustness of 0.84%, 27.33%, 28.99%, and 17.61% against adversarial attacks compared with several state-of-the-art adversarial training methods on the MNIST, CIFAR-10, CIFAR-100, and GTSRB datasets, respectively. Thus, the proposed HAT method results in improved robustness for DNNs against a wider range of adversarial attacks.
Particle Image Velocimetry Measurements in Accelerated, Transonic Wake Flows
Authors: Richter Judith , Alexopoulos Charalampos , Weigand Bernhard
Published: August 2022

This paper reports on particle image velocimetry (PIV) measurements in compressible accelerated wake flows generated by two different central injector types, which are mounted in a convergent-divergent nozzle. The injectors differ by the extent of their trailing edge located either in the subsonic (injector A) or supersonic flow region (injector B). In addition, the undisturbed nozzle flow without injector is studied as a reference case. The PIV results reveal typical wake flow structures expected in subsonic (injector A) and supersonic (injector B) wake flows. They further show that the Reynolds stresses $$\mathrm {Re_{xx}}$$

Re
xx

and $$\mathrm {Re_{yy}}$$

Re
yy

significantly decay in all three cases due to the strong acceleration throughout the nozzle. Interestingly, in the case of injector A, the flow stays non-isotropic with $$\mathrm {Re_{yy}}>\mathrm {Re_{xx}}$$

Re
yy

>

Re
xx

also far downstream in the supersonic flow region. These measurements were motivated by the lack of velocity data needed to validate numerical simulations. That is why this paper additionally contains results from (unsteady) Reynolds-averaged Navier-Stokes ((U)RANS) simulations of the two wake flows investigated experimentally. The URANS simulation of the injector A case is able to accurately predict the entire flow field and periodic fluctuations at the wake centerline. However, in the case of injector B, the RANS simulation underestimates the far wake centerline velocity by about $$4\%$$

4
%

.
Microaggressions, Interrupted: The Experience and Effects of Gender Microaggressions for Women in STEM
Authors: Kim Jennifer Y. , Meister Alyson
Published: August 2022

Women continue to remain underrepresented in STEM, and this gender disparity is particularly pronounced in leadership positions. Through in-depth, qualitative interviews of 39 women leaders in STEM, we identify common gender microaggressions they experience, and explore how these microaggressions affect their leadership experience and outcomes in the workplace. Our findings highlight five types of gender microaggressions women most often encounter, and how and when these microaggressions occur. We explore the negative impact that microaggressions can have on women’s work identities and how they can trigger a cycle of rumination and self-doubt that may ultimately result in women choosing to leave STEM. Importantly, we surface the interventional and empowering role that allies play in triggering a redemptive sensemaking process that can support women leaders to build resilience and counter the negative effects of microaggressions.
Clinical Outcome of Paclitaxel-Coated Balloon Angioplasty Versus Drug-Eluting Stent Implantation for the Treatment of Coronary Drug-Eluting Stent In-Stent Chronic Total Occlusion
Authors: Zhang Yuchao , Wu Zheng , Wang Shaoping , Liu Tong , Liu Jinghua
Published: August 2022

Aims

In-stent chronic total occlusion (IS-CTO) represents a unique challenge for percutaneous coronary intervention. Whether the optimal treatment for IS-CTO is angioplasty with paclitaxel-coated balloons (PCBs) or repeat stenting with drug-eluting stents (DESs) is unclear. We aimed to evaluate the long-term clinical outcome of PCB angioplasty and DES repeat stenting for DES IS-CTO.

Methods

We retrospectively included patients with DES IS-CTO who underwent successful PCB angioplasty or DES repeat stenting from January 2016 to December 2019. The primary endpoints were major adverse cardiac events (MACEs), including cardiac death, myocardial infarction, and target lesion revascularization (TLR). Cox proportional hazards model was performed to compare the risk of MACEs between PCB angioplasty and DES repeat stenting, and to further explore the prognostic factors of patients with DES IS-CTO.

Results

A total of 214 patients with DES IS-CTO were enrolled: 78 patients (36.4%) treated with PCB and 136 patients (63.6%) treated with DES respectively. The median follow-up was 1160 days, and MACEs were observed in 28.2% of patients with PCB angioplasty versus 26.5% of patients with DES repeat stenting (P = 0.784), mainly driven by TLR (21.8% vs. 19.9%, P = 0.735). There was no significant difference in the risk of MACEs between the PCB group and the DES group (hazard ratio [HR] 1.25, 95% confidence interval [CI] 0.64–2.46, P = 0.512). Multivariate Cox analysis revealed that chronic kidney disease and ≥ 3 stent layers in the lesion were independent predictors of MACEs, while switching to another antiproliferative drug was an independent protective factor (all P < 0.05).

Conclusions

PCB angioplasty was an effective alternative treatment strategy for DES IS-CTO, which had similar long-term outcomes to DES repeat stenting in contemporary practice, but both were accompanied by a high rate of long-term MACEs. Improving the poor prognosis of patients with DES IS-CTO remains a challenge.
A study of children emotion and their performance while handwriting Arabic characters using a haptic device
Authors: Zakraoui Jezia , Saleh Moutaz , Al-Maadeed Somaya , AlJa’am Jihad Mohamad
Published: August 2022

Emotion and focus of children during handwriting are essential for language learning. Handwriting for young children is challenging because it needs deep motivation and willingness to complete the task regardless of its difficulty. Recently, emerged haptic guidance systems have a good potential to offer children a better sense of engagement to keep their interests awake. Yet, handwriting in 3D is more challenging for children due to many reasons including demotivation, out of focus, and visuomotor coordination difficulties. In this paper, we study the effectiveness of a haptic device in analyzing schoolchildren emotion, attentiveness and handwriting performance of Arabic letters. We conducted the experiments for a period of four weeks with an immersive environment where the subjects practiced writing in VR environment using a haptic device-controlled stylus. We assessed the childrens’ emotions to get insights into their engagement during such hard learning environment. We found that our approach improved the participants’ fine-motor skills and handwriting quality. However, our analysis revealed that such task was effective on detecting emotions (angry/neutral) only as a negative/positive contributor of performance. Overall, the obtained findings can well contribute to the understanding of the relationship between students’ emotions and other variables in an attempt to support the development of adaptive learning technologies.
Exploring the impacts of learning modality changes: Validation of the learning modality change community of inquiry and self-efficacy scales
Authors: Jia Yuane , Gesing Peggy , Jun Hyun-Jin , Burbage Amanda K. , Hoang Thuha , Kulo Violet , Cestone Christina , McBrien Sarah , Tornwall Joni
Published: August 2022

The rapid learning environment transition initiated by the COVID-19 pandemic impacted students’ perception of, comfort with, and self-efficacy in the online learning environment. Garrison’s Community of Inquiry framework provides a lens for examining students’ online learning experiences through three interdependent elements: social presence, cognitive presence, and teaching presence. Researchers in this study developed and validated the Learning Modality Change Community of Inquiry and Self-Efficacy scales to measure health professions students’ self-efficacy with online learning, while exploring how cognitive, social, and teaching presence is experienced by students who transition from one learning environment to another. The two scales demonstrate strong validity and reliability evidence and can be used by educators to explore the impacts of learning modality changes on student learning experiences. As learning environments continue to evolve, understanding the impact of these transitions can inform how educators consider curriculum design and learning environment changes.
Oral Language and Emergent Literacy Strategies Used by Australian Early Childhood Teachers During Shared Book Reading
Authors: Weadman Tessa , Serry Tanya , Snow Pamela C.
Published: August 2022

The use of shared book reading is regarded as valuable to support young children to build their oral language and emergent literacy skills in preschool classrooms. Quantitative and qualitative features of early childhood teachers’ (ECTs’) shared book reading practices are important contributors to quality shared book reading experiences. The aim of this study was to gain in-depth insights about the range and frequency of extratextual oral language and emergent literacy utterances (utterances beyond the story text) used by ECTs during shared book reading with preschoolers as well as their use of paralinguistic and nonverbal features. Video-recordings were made of 32 ECTs engaging in shared book reading with their four-year-old preschool class. ECTs’ extratextual utterances and their paralinguistic and nonverbal features were classified using a validated observational checklist: The “Emergent Literacy and Language Early Childhood Checklist for Teachers” (ELLECCT). Results showed ECTs frequently used responsive statements such as commenting on the story or acknowledging or imitating children’s utterances in book-related talk. ECTs most commonly asked closed questions during shared book reading and regularly used paralinguistic and nonverbal features such as prosody and volume in order to engage children. In contrast, ECTs used only a limited range of dialogic reading prompts and explicit vocabulary strategies and only infrequently expanded children’s utterances. Notably, ECTs rarely used strategies to target children’s print knowledge or phonological awareness. Although extratextual dialogue was used regularly by ECTs during shared book reading, targeted techniques that are known to build oral language and emergent literacy were not consistently demonstrated. These results suggest missed opportunities for preschool children to benefit from shared book reading.
Joint modelling of audio-visual cues using attention mechanisms for emotion recognition
Authors: Ghaleb Esam , Niehues Jan , Asteriadis Stylianos
Published: August 2022

Emotions play a crucial role in human-human communications with complex socio-psychological nature. In order to enhance emotion communication in human-computer interaction, this paper studies emotion recognition from audio and visual signals in video clips, utilizing facial expressions and vocal utterances. Thereby, the study aims to exploit temporal information of audio-visual cues and detect their informative time segments. Attention mechanisms are used to exploit the importance of each modality over time. We propose a novel framework that consists of bi-modal time windows spanning short video clips labeled with discrete emotions. The framework employs two networks, with each one being dedicated to one modality. As input to a modality-specific network, we consider a time-dependent signal deriving from the embeddings of the video and audio modalities. We employ the encoder part of the Transformer on the visual embeddings and another one on the audio embeddings. The research in this paper introduces detailed studies and meta-analysis findings, linking the outputs of our proposition to research from psychology. Specifically, it presents a framework to understand underlying principles of emotion recognition as functions of three separate setups in terms of modalities: audio only, video only, and the fusion of audio and video. Experimental results on two datasets show that the proposed framework achieves improved accuracy in emotion recognition, compared to state-of-the-art techniques and baseline methods not using attention mechanisms. The proposed method improves the results over baseline methods by at least 5.4%. Our experiments show that attention mechanisms reduce the gap between the entropies of unimodal predictions, which increases the bimodal predictions’ certainty and, therefore, improves the bimodal recognition rates. Furthermore, evaluations with noisy data in different scenarios are presented during the training and testing processes to check the framework’s consistency and the attention mechanism’s behavior. The results demonstrate that attention mechanisms increase the framework’s robustness when exposed to similar conditions during the training and the testing phases. Finally, we present comprehensive evaluations of emotion recognition as a function of time. The study shows that the middle time segments of a video clip are essential in the case of using audio modality. However, in the case of video modality, the importance of time windows is distributed equally.
Distribution Patterns of Astrocyte Populations in the Human Cortex
Authors: Forrest Shelley L. , Kim Jordan Hanxi , Crockford Daniel R. , Huynh Katharine , Cheong Rosie , Knott Samantha , Kane Madison A. , Ittner Lars M. , Halliday Glenda M. , Kril Jillian J.
Published: August 2022

Astrocytes are a major class of glial cell in the central nervous system that have a diverse range of types and functions thought to be based on their anatomical location, morphology and cellular properties. Recent studies highlight that astrocyte dysfunction contributes to the pathogenesis of neurological conditions. However, few studies have described the pattern, distribution and density of astrocytes in the adult human cortex. This study mapped the distribution and density of astrocytes immunolabelled with a range of cytoskeletal and membrane markers in the human frontal cortex. Distinct and overlapping astrocyte populations were determined. The frontal cortex from ten normal control cases (75 ± 9 years) was immunostained with glial fibrillary acidic protein (GFAP), aldehyde dehydrogenase-1 L1 (ALDH1L1), connexin-43 (Cx43), aquaporin-4 (AQP4), and glutamate transporter 1 (GLT-1). All markers labelled populations of astrocytes in the grey and white matter, separate cortical layers, subpial and perivascular regions. All markers were informative for labelling different cellular properties and cellular compartments of astrocytes. ALDH1L1 labelled the largest population of astrocytes, and Cx43-immunopositive astrocytes were found in all cortical layers. AQP4 and GLT-1 labelled distal astrocytic process and end-feet in the same population of astrocytes (98% of GLT-1-immunopositive astrocytes contained AQP4). In contrast, GFAP, the most widely used marker, predominantly labelled astrocytes in superficial cortical layers. This study highlights the diversity of astrocytes in the human cortex, providing a reference map of the distribution of distinct and overlapping astrocyte populations which can be used for comparative purposes in various disease, inflammatory and injury states involving astrocytes.
Latency and Crisis: Mutual Aid Activism in the Covid-19 Pandemic
Authors: Ferrari Elisabetta
Published: August 2022

Activists have responded to the Covid-19 pandemic by organizing for mutual aid: creating collective action to meet people’s material needs and build ties of solidarity. I examine the difficulties encountered by mutual aid activists during the pandemic through Alberto Melucci’s notions of latency and collective identity. Through digital ethnographic observations of the Instagram accounts of mutual aid groups based in Philadelphia, USA, as well as interviews with the activists, I explore how mutual aid, conceptualized as latency work, was practiced by activists in the unprecedented conditions of the pandemic and how activists approached collective identity processes. I show that activists experienced a compression of latency and mobilization within the crisis context of the pandemic, which made it more difficult for them to pursue the construction of a collective identity. I also suggest that the effects of this compression were further exacerbated by the logic of immediacy that characterizes social network sites.
Practical issues to consider when working with big data
Authors: Stice-Lawrence Lorien
Published: August 2022

Increasing access to alternative or “big data” sources has given rise to an explosion in the use of these data in economics-based research. However, in our enthusiasm to use the newest and greatest data, we as researchers may jump to use big data sources before thoroughly considering the costs and benefits of a particular dataset. This article highlights four practical issues that researchers should consider before working with a given source of big data. First, big data may not be conceptually different from traditional data. Second, big data may only be available for a limited sample of individuals, especially when aggregated to the unit of interest. Third, the sheer volume of data coupled with high levels of noise can make big data costly to process while still producing measures with low construct validity. Last, papers using big data may focus on the novelty of the data at the expense of the research question. I urge researchers, in particular PhD students, to carefully consider these issues before investing time and resources into acquiring and using big data.