bluuebunny/crossref_metadata_2025 huggingface dataset:
Brain Drain or Brain Circulation? Economic and Non-Economic Factors Driving the International Migration of German Citizens
Authors: Ette Andreas , Witte Nils
Published: April 2021

International movements by people from economically highly developed welfare states are a puzzle for the classic canon of migration theories, which generally focus on flows from less to more developed regions. Based on a simple theoretical framework linking largely disparate literatures on international and internal migration as well as the field of global work experience, this chapter provides an analysis of the emigration and remigration decisions of German citizens. Whereas the five theoretical dimensions-expected financial returns, job satisfaction, social capital, mobility capital, and employment in transnational professions-already explain much of the variance in the emigration decisions, the theoretical and empirical understanding of remigration decision-making processes remains a challenge. Contributing to recent debates about a brain drain from economically highly developed countries, this chapter provides evidence that the international migration of German citizens is best understood as brain circulation. Temporary migration dominates these international movements and emigrants are similar to remigrants along many theoretical dimensions. Although some indications for a potential loss of human capital caused by international migration do exist, they remain insignificant in light of Germany’s overall volume of international migration. Political debates about flows of people from highly developed countries should focus less on potential losses of human capital for national economies and more on the economic and non-economic returns international migration offers for individual life courses.
Comparing the Risk Attitudes of Internationally Mobile and Non-Mobile Germans
Authors: Lübke Christiane , Décieux Jean P. , Erlinghagen Marcel , Wagner Gert G.
Published: April 2021

Moving–particularly to a new country–is fraught with risks as migrants leave familiar legal frameworks and cultural institutions behind them. To date, little is known about the psychological determinants of international migration. This chapter helps to fill this gap by analysing data from the first wave of the German Emigration and Remigration Panel Study (GERPS) in combination with data on non-mobile individuals from the German Socio-Economic Panel Study (SOEP). The analyses presented examine whether the risk attitudes of internationally mobile Germans (‘movers’) differ from those of their non-mobile counterparts (‘stayers’). The results show that–with control for key socio-demographic and socio-economic determinants of risk affinity–both emigrants and remigrants report a significantly higher willingness to take risks than stayers. Risk affinity differs within the group of internationally mobile individuals: Emigrants moving to geographically and culturally distant non-European countries report higher risk affinity than those moving to Germany’s neighbouring countries. Emigrants with multiple previous emigration periods are also more willing to take risks. These findings suggest that voluntary emigration from wealthy countries like Germany is only partly a matter of living conditions. Rather, (repeated) emigration seems to be a matter of personality and an expression of a more adventurous lifestyle.
1/N expansion of circular Wilson loop in $$ \mathcal{N} $$ = 2 superconformal SU(N) × SU(N) quiver
Authors: Beccaria M. , Tseytlin A.A.
Published: April 2021

Abstract

Localization approach to $$ \mathcal{N} $$
N
= 2 superconformal SU(N) × SU(N) quiver theory leads to a non-Gaussian two-matrix model representation for the expectation value of BPS circular SU(N) Wilson loop $$ \left\langle \mathcal{W}\right\rangle $$

W

. We study the subleading 1/N2 term in the large N expansion of $$ \left\langle \mathcal{W}\right\rangle $$

W

at weak and strong coupling. We concentrate on the case of the symmetric quiver with equal gauge couplings which is equivalent to the ℤ2 orbifold of the SU(2N) $$ \mathcal{N} $$
N
= 4 SYM theory. This orbifold gauge theory should be dual to type IIB superstring in AdS5 × (S5/ℤ2). We present a string theory argument suggesting that the 1/N2 term in $$ \left\langle \mathcal{W}\right\rangle $$

W

in the orbifold theory should have the same strong-coupling asymptotics λ3/2 as in the $$ \mathcal{N} $$
N
= 4 SYM case. We support this prediction on the gauge theory side by a numerical study of the localization matrix model. We also find a relation between the 1/N2 term in the Wilson loop expectation value and the derivative of the free energy of the orbifold gauge theory on 4-sphere.
Dimers in a bottle
Authors: García-Valdecasas Eduardo , Meynet Shani , Pasternak Antoine , Tatitscheff Valdo
Published: April 2021

Abstract

We revisit D3-branes at toric CY3 singularities with orientifolds and their description in terms of dimer models. We classify orientifold actions on the dimer through smooth involutions of the torus. In particular, we describe new orientifold projections related to maps on the dimer without fixed points, leading to Klein bottles. These new orientifolds lead to novel $$ \mathcal{N} $$
N
= 1 SCFT’s that resemble, in many aspects, non-orientifolded theories. For instance, we recover the presence of fractional branes and some of them trigger a cascading RG-flow à la Klebanov-Strassler. The remaining involutions lead to non-supersymmetric setups, thus exhausting the possible orientifolds on dimers.
Sun heated MeV-scale dark matter and the XENON1T electron recoil excess
Authors: Chen Yifan , Cui Ming-Yang , Shu Jing , Xue Xiao , Yuan Guan-Wen , Yuan Qiang
Published: April 2021

Abstract

The XENON1T collaboration reported an excess of the low-energy electron recoil events between 1 and 7 keV. We explore the possibility to explain such an anomaly by the MeV-scale dark matter (DM) heated by the interior of the Sun due to the same DM-electron interaction as in the detector. The kinetic energies of heated DM particles can reach a few keV, and can potentially account for the excess signals detected by XENON1T. We study different form factors of the DM-electron interactions, F(q) ∝ qi with q being the momentum exchange and i = 0, 1, 2, and find that for all these cases the inclusion of the Sun-heated DM component improves the fit to the XENON1T data. The inferred DM-electron scattering cross section (at q = αme where α is the fine structure constant and me is electron mass) is from ∼ 10−38 cm2 (for i = 0) to ∼ 10−42 cm2 (for i = 2). We also derive constraints on the DM-electron cross sections for these form factors, which are stronger than previous results with similar assumptions. We emphasize that the Sun-heated DM scenario relies on the minimum assumption on DM models, which serves as a general explanation of the XENON1T anomaly via DM-electron interaction. The spectrum of the Sun-heated DM is typically soft comparing to other boosted DM, so the small recoil events are expected to be abundant in this scenario. More sensitive direct detection experiments with lower thresholds can possibly distinguish this scenario with other boosted DM models or solar axion models.
CP violation in mixing and oscillations in a toy model for leptogenesis with quasi-degenerate neutrinos
Authors: Racker J.
Published: April 2021

Abstract

We study the sources of CP violation for baryogenesis models with quasi-degenerate neutrinos. Our approach is to use the renormalized propagator in a quantum field theory model of neutrino oscillations, paying close attention to unitarity requirements. From the probabilities of lepton number violating processes obtained in this way, we derive a source term for the time evolution of the lepton asymmetry. The source term has contributions that can be identified with CP violation from mixing, oscillations and interference between both. Given that this source term does not involve processes with unstable particles in the initial or final states, neither does it require to calculate number densities of neutrinos, no subtraction of real intermediate states must be performed. In equilibrium the source term is null, as demanded by unitarity and CPT invariance, due to a cancellation between the terms coming from CP violation in mixing and oscillations. The calculations are done in a simple scalar toy model, and the resummed propagator is diagonalized at first order in the decay widths over the mass difference. We also comment on the effect of the interference term, which is mild at the order we work, but seems to become more important with increasing degeneracy.
A Survey of the Elastic Flow of Curves and Networks
Authors: Mantegazza Carlo , Pluda Alessandra , Pozzetta Marco
Published: April 2021

We collect and present in a unified way several results in recent years about the elastic flow of curves and networks, trying to draw the state of the art of the subject. In particular, we give a complete proof of global existence and smooth convergence to critical points of the solution of the elastic flow of closed curves in$${\mathbb {R}}^2$$R2. In the last section of the paper we also discuss a list of open problems.
The Jang Equation and the Positive Mass Theorem in the Asymptotically Hyperbolic Setting
Authors: Sakovich Anna
Published: April 2021

We solve the Jang equation with respect to asymptotically hyperbolic “hyperboloidal” initial data. The results are applied to give a non-spinor proof of the positive mass theorem in the asymptotically hyperbolic setting. This work focuses on the case when the spatial dimension is equal to three.
EANM position paper on the role of radiobiology in nuclear medicine
Authors: Aerts An , Eberlein Uta , Holm Sören , Hustinx Roland , Konijnenberg Mark , Strigari Lidia , van Leeuwen Fijs W.B. , Glatting Gerhard , Lassmann Michael
Published: April 2021

Executive Summary

With an increasing variety of radiopharmaceuticals for diagnostic or therapeutic nuclear medicine as valuable diagnostic or treatment option, radiobiology plays an important role in supporting optimizations. This comprises particularly safety and efficacy of radionuclide therapies, specifically tailored to each patient. As absorbed dose rates and absorbed dose distributions in space and time are very different between external irradiation and systemic radionuclide exposure, distinct radiation-induced biological responses are expected in nuclear medicine, which need to be explored. This calls for a dedicated nuclear medicine radiobiology. Radiobiology findings and absorbed dose measurements will enable an improved estimation and prediction of efficacy and adverse effects. Moreover, a better understanding on the fundamental biological mechanisms underlying tumor and normal tissue responses will help to identify predictive and prognostic biomarkers as well as biomarkers for treatment follow-up. In addition, radiobiology can form the basis for the development of radiosensitizing strategies and radioprotectant agents. Thus, EANM believes that, beyond in vitro and preclinical evaluations, radiobiology will bring important added value to clinical studies and to clinical teams. Therefore, EANM strongly supports active collaboration between radiochemists, radiopharmacists, radiobiologists, medical physicists, and physicians to foster research toward precision nuclear medicine.
Unusual Left Periclavicular Cutaneous Lymphatic Fistula After Port Explantation Without Lymph Vessel Injury: Imaging and Interventional Treatment
Authors: Wagenpfeil Julia , Attenberger Ulrike , Pieper Claus Christian
Published: April 2021

Complex oncological treatment can be associated with lymphatic vascular injury that is burdened by considerable morbidity. Lymphatic imaging and interventional techniques offer new minimally invasive treatment options. We report the case of a 59-year-old woman with an unusual lympho-veno-cutaneous fistula, diagnosed by magnetic resonance lymphangiography and treated by minimally invasive embolization therapy and venous recanalization.
Functional connectivity in mild cognitive impairment with Lewy bodies
Authors: Schumacher Julia , Taylor John-Paul , Hamilton Calum A. , Firbank Michael , Donaghy Paul C. , Roberts Gemma , Allan Louise , Durcan Rory , Barnett Nicola , O’Brien John T. , Thomas Alan J.
Published: April 2021

Previous resting-state fMRI studies in dementia with Lewy bodies have described changes in functional connectivity in networks related to cognition, motor function, and attention as well as alterations in connectivity dynamics. However, whether these changes occur early in the course of the disease and are already evident at the stage of mild cognitive impairment is not clear. We studied resting-state fMRI data from 31 patients with mild cognitive impairment with Lewy bodies compared to 28 patients with mild cognitive impairment due to Alzheimer’s disease and 24 age-matched controls. We compared the groups with respect to within- and between-network functional connectivity. Additionally, we applied two different approaches to study dynamic functional connectivity (sliding-window analysis and leading eigenvector dynamic analysis). We did not find any significant changes in the mild cognitive impairment groups compared to controls and no differences between the two mild cognitive impairment groups, using static as well as dynamic connectivity measures. While patients with mild cognitive impairment with Lewy bodies already show clear functional abnormalities on EEG measures, the fMRI analyses presented here do not appear to be sensitive enough to detect such early and subtle changes in brain function in these patients.
The role of HCO3– in propionate-induced anion secretion across rat caecal epithelium
Authors: Ballout Jasmin , Diener Martin
Published: April 2021

Propionate, a metabolite from the microbial fermentation of carbohydrates, evokes a release of epithelial acetylcholine in rat caecum resulting in an increase of short-circuit current (Isc) in Ussing chamber experiments. The present experiments were performed in order to characterize the ionic mechanisms underlying this response which has been thought to be due to Cl−secretion. As there are regional differences within the caecal epithelium, the experiments were conducted at oral and aboral rat corpus caeci. In both caecal segments, the propionate-inducedIsc(IProp) was inhibited by > 85%, when the experiments were performed either in nominally Cl−- or nominally HCO3−-free buffer. In the case of Cl−, the dependency was restricted to the presence of Cl−in the serosal bath. Bumetanide, a blocker of the Na+-K+-2Cl−-cotransporter, only numerically reducedIPropsuggesting that a large part of this current must be carried by an ion other than Cl−. In the aboral caecum,IPropwas significantly inhibited by mucosally administered stilbene derivatives (SITS, DIDS, DNDS), which block anion exchangers. Serosal Na+-free buffer reduced IPropsignificantly in the oral (and numerically also in aboral) corpus caeci. RT-PCR experiments revealed the expression of several forms of Na+-dependent HCO3−-cotransporters in caecum, which might underlie the observed Na+dependency. These results suggest that propionate sensing in caecum is coupled to HCO3–secretion, which functionally would stabilize luminal pH when the microbial fermentation leads to an increase in the concentration of short-chain fatty acids in the caecal lumen.
The evolution of imprinting in plants: beyond the seed
Authors: Montgomery Sean A. , Berger Frédéric
Published: April 2021

Genomic imprinting results in the biased expression of alleles depending on if the allele was inherited from the mother or the father. Despite the prevalence of sexual reproduction across eukaryotes, imprinting is only found in placental mammals, flowering plants, and some insects, suggesting independent evolutionary origins. Numerous hypotheses have been proposed to explain the selective pressures that favour the innovation of imprinted gene expression and each differs in their experimental support and predictions. Due to the lack of investigation of imprinting in land plants, other than angiosperms with triploid endosperm, we do not know whether imprinting occurs in species lacking endosperm and with embryos developing on maternal plants. Here, we discuss the potential for uncovering additional examples of imprinting in land plants and how these observations may provide additional support for one or more existing imprinting hypotheses.
Postural differences in the immediate effects of active exercise with compression therapy on lower limb lymphedema
Authors: Abe Kiriko , Tsuji Tetsuya , Oka Asako , Shoji Junichi , Kamisako Michiyo , Hohri Hiroka , Ishikawa Aiko , Liu Meigen
Published: April 2021

Purpose

Although regarded as an important treatment for lymphedema, the therapeutic effects of active exercise with compression therapy (AECT) are supported by little evidence. The purpose of this study was to determine the relative benefits of AECT with different postures for patients with lower limb lymphedema (LLL).

Methods

Eighteen women with LLL secondary to surgical treatment of gynecological cancer, completed (1) AECT in a seated position (seated AECT), (2) AECT in a supine position (supine AECT), and (3) compression-only therapy in a supine position (CT) in this randomized, controlled, crossover trial. AECT was performed on a bicycle ergometer while wearing elastic compression bandages. Each intervention was performed for 15 min, and the three conditions were separated by a 1-week washout period. Lower-limb volumes were evaluated using a PerometerTM sensor (Pero-system, Wuppertal, Germany), and symptom severity was assessed before and after each intervention using a visual analog scale (pain, heaviness) and palpation (pitting, stiffness). The effects of the interventions were estimated using linear mixed-effect models.

Results

The magnitude of limb volume decreases differed significantly among the interventions, with a greater decrease after supine AECT than after CT. Pre-intervention pitting severity and skin stiffness were significantly correlated with the magnitude of volume decrease after all interventions and after AECT in the supine position, respectively.

Conclusions

Supine AECT using a bicycle ergometer has marked immediate effects to decrease the fluid volume of severe LLL.

Clinical trial registration

UMIN clinical trial registry (UMIN-CTR; ID000020129) by CONSORT 2010, TRN R000023253, December 9, 2015
A novel augmented deep transfer learning for classification of COVID-19 and other thoracic diseases from X-rays
Authors: Altaf Fouzia , Islam Syed M. S. , Janjua Naeem Khalid
Published: April 2021

Deep learning has provided numerous breakthroughs in natural imaging tasks. However, its successful application to medical images is severely handicapped with the limited amount of annotated training data. Transfer learning is commonly adopted for the medical imaging tasks. However, a large covariant shift between the source domain of natural images and target domain of medical images results in poor transfer learning. Moreover, scarcity of annotated data for the medical imaging tasks causes further problems for effective transfer learning. To address these problems, we develop an augmented ensemble transfer learning technique that leads to significant performance gain over the conventional transfer learning. Our technique uses an ensemble of deep learning models, where the architecture of each network is modified with extra layers to account for dimensionality change between the images of source and target data domains. Moreover, the model is hierarchically tuned to the target domain with augmented training data. Along with the network ensemble, we also utilize an ensemble of dictionaries that are based on features extracted from the augmented models. The dictionary ensemble provides an additional performance boost to our method. We first establish the effectiveness of our technique with the challenging ChestXray-14 radiography data set. Our experimental results show more than 50% reduction in the error rate with our method as compared to the baseline transfer learning technique. We then apply our technique to a recent COVID-19 data set for binary and multi-class classification tasks. Our technique achieves 99.49% accuracy for the binary classification, and 99.24% for multi-class classification.
Trends in admissions to a child and adolescent neuropsychiatric inpatient unit in the 2007–2017 decade: how contemporary neuropsychiatry is changing in Northwestern Italy
Authors: Amianto Federico , Arletti Luca , Baietto Chiara , Davico Chiara , Migliaretti Giuseppe , Vitiello Benedetto
Published: April 2021

Purpose

Rising levels of psychopathology in the adolescent population have been evidenced in the last few years throughout the Western world. We aim to examine how contemporary neuropsychiatry is changing in Northwestern Italy and how this impacts inpatient services.

Methods

The present research considered the 1177 admissions to a public neuropsychiatric inpatient service in the 2007–2017 decade. The annual percentual change (APC) was analysed for the total admissions, the number of the neurological vs psychiatric admissions, the length of inpatient stay, and the mean age at admission, also accounting for sex differences. The annual trend was also calculated for each diagnosis.

Results

The overall number of inpatient admissions decreased significantly (APC = − 5.91), in particular for children under 12 years of age (APC = − 7.23). The rate of neurologic diagnoses significantly decreased (APC = − 26.44), while the length of the inpatient stay (APC = 6.98) and the mean age at admission (APC = 6.69) increased. Among the psychiatric diagnoses, depression significantly rose (APC = 41.89), in particular among female adolescents (APC = 40.30).

Conclusions

These data document a substantial change in the utilization of inpatient neuropsychiatric services for children and adolescents, with a major increase in psychiatric hospitalizations and a parallel decrease in neurological ones. These trends call for greater attention to early preventive intervention in mental healthcare system.
Safety and efficacy of panitumumab in combination with trifluridine/tipiracil for pre-treated patients with unresectable, metastatic colorectal cancer with wild-type RAS: The phase 1/2 APOLLON study
Authors: Kato Takeshi , Kagawa Yoshinori , Kuboki Yasutoshi , Gamoh Makio , Komatsu Yoshito , Yasui Hirofumi , Satake Hironaga , Oki Eiji , Tanioka Hiroaki , Kotaka Masahito , Makiyama Akitaka , Denda Tadamichi , Goto Masahiro , Yoshino Takayuki , Yamazaki Kentaro , Soeda Junpei , Shibuya Kazunori , Iwata Masaru , Oba Koji , Yamaguchi Kensei
Published: April 2021

Background

We aimed to assess the safety and efficacy of combination treatment with panitumumab plus trifluridine/tipiracil (FTD/TPI) in patients with wild-type RAS metastatic colorectal cancer (mCRC) who were refractory/intolerant to standard therapies other than anti-epidermal growth factor receptor therapy.

Methods

APOLLON was an open-label, multicentre, phase 1/2 trial. In the phase 1 part, 3 + 3 de-escalation design was used to investigate the recommended phase 2 dose (RP2D); all patients in the phase 2 part received the RP2D. The primary endpoint was investigator-assessed progression-free survival (PFS) rate at 6 months. Secondary endpoints included PFS, overall survival (OS), overall response rate (ORR), disease control rate (DCR), time to treatment failure (TTF), and safety.

Results

Fifty-six patients were enrolled (phase 1, n = 7; phase 2, n = 49) at 25 Japanese centres. No dose-limiting toxicities were observed in patients receiving panitumumab (6 mg/kg every 2 weeks) plus FTD/TPI (35 mg/m2 twice daily; days 1–5 and 8–12 in a 28-day cycle), which became RP2D. PFS rate at 6 months was 33.3% (90% confidence interval [CI] 22.8–45.3). Median PFS, OS, ORR, DCR, and TTF were 5.8 months (95% CI 4.5–6.5), 14.1 months (95% CI 12.2–19.3), 37.0% (95% CI 24.3–51.3), 81.5% (95% CI 68.6–90.8), and 5.8 months (95% CI 4.29–6.21), respectively. Neutrophil count decreased (47.3%) was the most common Grade 3/4 treatment-emergent adverse event. No treatment-related deaths occurred.

Conclusion

Panitumumab plus FTD/TPI exhibited favourable anti-tumour activity with a manageable safety profile and may be a therapeutic option for pre-treated mCRC patients.
Toddlers’ peer engagement in Swiss childcare: contribution of individual and contextual characteristics
Authors: Diebold Tatiana , Perren Sonja
Published: April 2021

The present study observed 86 three-year-old children (M = 43.7, SD = 6.4) from 15 Swiss childcare groups, to investigate multiple individual and contextual contributions to toddlers’ positive engagement with peers. The children’s individual characteristics (age, sex and social skills) and childcare-related predictors (emotional and behavioural support from caregivers, and structural group features) were assessed. We employed the child-by-environment perspective and tested the hypothesis that high-quality behavioural and emotional support provided by caregivers benefits children with deficits in social abilities. Results of the multilevel structural equation modelling indicated that toddlers rated by caregivers as sociable and assertive showed more positive situation-specific peer engagement, especially with a concomitant higher quality of caregiver emotional and behavioural support. By contrast, being prosocial-cooperative was negatively associated with observed peer engagement. Thus, children’s social skills were found to be the most important factor for peer engagement in childcare settings. Important suggestions for future research are made, and practical implications are discussed.
In-Stent Restenosis Progression in Human Superficial Femoral Arteries: Dynamics of Lumen Remodeling and Impact of Local Hemodynamics
Authors: Colombo Monika , He Yong , Corti Anna , Gallo Diego , Ninno Federica , Casarin Stefano , Rozowsky Jared M , Migliavacca Francesco , Berceli Scott , Chiastra Claudio
Published: April 2021

In-stent restenosis (ISR) represents a major drawback of stented superficial femoral arteries (SFAs). Motivated by the high incidence and limited knowledge of ISR onset and development in human SFAs, this study aims to (i) analyze the lumen remodeling trajectory over 1-year follow-up period in human stented SFAs and (ii) investigate the impact of altered hemodynamics on ISR initiation and progression. Ten SFA lesions were reconstructed at four follow-ups from computed tomography to quantify the lumen area change occurring within 1-year post-intervention. Patient-specific computational fluid dynamics simulations were performed at each follow-up to relate wall shear stress (WSS) based descriptors with lumen remodeling. The largest lumen remodeling was found in the first post-operative month, with slight regional-specific differences (larger inward remodeling in the fringe segments, p < 0.05). Focal re-narrowing frequently occurred after 6 months. Slight differences in the lumen area change emerged between long and short stents, and between segments upstream and downstream from stent overlapping portions, at specific time intervals. Abnormal patterns of multidirectional WSS were associated with lumen remodeling within 1-year post-intervention. This longitudinal study gave important insights into the dynamics of ISR and the impact of hemodynamics on ISR progression in human SFAs.
Determination of near-fault impulsive signals with multivariate naïve Bayes method
Authors: Ertuncay Deniz , Costa Giovanni
Published: April 2021

Near-fault ground motions may contain impulse behavior on velocity records. To calculate the probability of occurrence of the impulsive signals, a large dataset is collected from various national data providers and strong motion databases. The dataset has a large number of parameters which carry information on the earthquake physics, ruptured faults, ground motion parameters, distance between the station and several parts of the ruptured fault. Relation between the parameters and impulsive signals is calculated. It is found that fault type, moment magnitude, distance and azimuth between a site of interest and the surface projection of the ruptured fault are correlated with the impulsiveness of the signals. Separate models are created for strike-slip faults and non-strike-slip faults by using multivariate naïve Bayes classifier method. Naïve Bayes classifier allows us to have the probability of observing impulsive signals. The models have comparable accuracy rates, and they are more consistent on different fault types with respect to previous studies.
Co-disposal of lignite fly ash and coal mine waste rock for neutralisation of AMD
Authors: Qureshi Asif , Maurice Christian , Öhlander Björn
Published: April 2021

Waste rocks (WRs) from a lignite-producing coalfield and fly ash (FA) produced from the same lignite have been investigated in this study with a primary objective to determine the potential for co-disposal of WRs and FA to reduce the environmental contamination. Mixing WRs with FA and covering WRs with FA have been investigated. Particle size effect caused ≤2 mm particles to produce low pH (~2) and metal-laden leachates, indicating higher sulphide minerals’ reactivity compared to larger particles (≤10 mm, pH ~ 4). Co-disposal of FA as mixture showed an instantaneous effect, resulting in higher pH (~3–6) and better leachate quality. However, acidity produced by secondary mineralisation caused stabilisation of pH at around 4.5–5. In contrast, the pH of the leachates from the cover method gradually increased from strongly acidic (pH ~ 2) to mildly acidic (pH ~ 4–5) and circumneutral (pH ~ 7) along with a decrease in EC and elemental leaching. Gradually increasing pH can be attributed to the cover effect, which reduces the oxygen diffusion, thus sulphide oxidation. FA cover achieved the pH necessary for secondary mineralisation during the leaching experiment. The co-disposal of FA as cover and/or mixture possesses the potential for neutralisation and/or slowing down AMD and improving leachate quality.
A review of combined sewer overflows as a source of wastewater-derived emerging contaminants in the environment and their management
Authors: Petrie Bruce
Published: April 2021

Emerging contaminants such as pharmaceuticals, illicit drugs and personal care products can be released to the environment in untreated wastewater/stormwater mixtures following storm events. The frequency and intensity of combined sewer overflows (CSOs) has increased in some areas due to increasing urbanisation and climate change. Therefore, this review provides an up-to-date overview on CSOs as an environmental source of emerging contaminants. Other than compounds with high removal, those chiral species subject to enantioselective changes (i.e. degradation or inversion) during wastewater treatment can be effective markers of CSO discharge in the environment. A proposed framework for the selection of emerging contaminants as markers of CSOs is outlined. Studies have demonstrated that CSOs can be the main source of emerging contaminants with high removal efficiency during wastewater treatment (e.g. > 90%). However, the impact of CSOs on the environment is location specific and requires decision-making on their appropriate management at catchment level. This process would be aided by further studies on CSOs which incorporate the monitoring of emerging contaminants and their effects in the environment with those more routinely monitored pollutants (e.g. pathogens and priority substances). Mitigation and treatment strategies for emerging contaminants in CSOs are also discussed.
Iodoprophylaxis and thyroid autoimmunity: an update
Authors: Teti Claudia , Panciroli Marta , Nazzari Elena , Pesce Giampaola , Mariotti Stefano , Olivieri Antonella , Bagnasco Marcello
Published: April 2021

Adequate iodine intake is necessary for normal thyroid function. Iodine deficiency is associated with serious complications, but also iodine excess can lead to thyroid dysfunction, and iodine supplementation aimed to prevent iodine deficiency disorders has been associated with development of thyroid autoimmunity. The epidemiology of thyroid diseases has undergone profound changes since the implementation of iodoprophylaxis, notably by means of iodine-enriched salt, specifically resulting in decreased prevalence of goiter and neonatal hypothyroidism, improved cognitive function development in infancy, and reduced incidence of more aggressive forms of thyroid cancer. The main question we address with this review is the clinical relevance of the possible effect on autoimmunity exerted by the use of iodine-enriched salt to correct iodine deficiency. In animal models, exogenous iodine is able to trigger or exacerbate thyroid autoimmunity, but it is still not clear whether the observed immunological changes are due to a direct effect of iodine on immune response, or whether they represent a secondary response to a toxic effect of iodine on thyroid tissue. Previous iodine status of a population seems to influence the functional thyroid response to increased iodine intake and possibly the development of thyroid autoimmunity. Moreover, the prevalence of thyroid antibodies, regarded as hallmark of autoimmune thyroid disease, varies between populations under the influence of genetic and environmental factors, and the presence of thyroid antibodies does not always coincide with the presence of thyroid disease or its future development. In addition, the incidence of autoimmune diseases shows a general increasing trend in the last decades. For all these reasons, available data are quite heterogeneous and difficult to analyze and compare. In conclusion, available data from long-term population surveys show that a higher than adequate population iodine intake due to a poorly controlled program of iodine prophylaxis could induce thyroid dysfunction, including thyroid autoimmunity mostly represented by euthyroid or subclinical hypothyroid autoimmune thyroiditis. Close monitoring iodine prophylaxis is therefore advised to ensure that effects of both iodine deficiency and iodine excess are avoided.
Monitoring deformations of Istanbul metro line stations through Sentinel-1 and levelling observations
Authors: Halicioglu Kerem , Erten Esra , Rossi Cristian
Published: April 2021

Turkey, as a developing country, is designing and performing massive construction projects around Istanbul. Beginning from the 1960s, rapid urbanization has been taking place due to industrialization, which brings an increase in the population. Yet, construction projects have been accelerated especially during the last decade, and many new projects are scheduled to be completed in a short time. Ground-based observations are generally carried out to monitor the deformations within construction sites, especially through geometric levelling, and GNSS techniques. However, in most cases, these monitoring measurements are only scheduled within the period of the construction process, and ensuing deformations are usually not considered. In addition to these techniques, the space-based interferometric technique can also be used to define the line of sight surface displacements with high accuracy, using the phase difference between image result for synthetic aperture radar images. In particular, Persistent Scatter Interferometry is one of the interferometric methods that are capable of defining the two-dimensional (vertical and horizontal) deformation for the desired epoch with a high temporal resolution. Thus it can be used as a complementary method for monitoring ground deformations, where the measurement is made by ground-based observations. In this study, the deforming areas related to underground metro construction are investigated through significant displacements between 2015 and 2018 of Sentinel-1 space-borne SAR data using the PSI technique. These results are validated by comparison with available levelling data corresponding to the new metro line.
Prevention of Ischemic Myocardial Contracture Through Hemodynamically Controlled DCD
Authors: Wahlquist Ylva , Soltesz Kristian , Liao Qiuming , Liu Xiaofei , Pigot Henry , Sjöberg Trygve , Steen Stig
Published: April 2021

Purpose

Ischemic myocardial contracture (IMC) or “stone heart” is a condition with rapid onset following circulatory death. It inhibits transplantability of hearts donated upon circulatory death (DCD). We investigate the effectiveness of hemodynamic normalization upon withdrawal of life-sustaining therapy (WLST) in a large-animal controlled DCD model, with the hypothesis that reduction in cardiac work delays the onset of IMC.

Methods

A large-animal study was conducted comprising of a control group ($$n=6$$

n
=
6

) receiving no therapy upon WLST, and a test group ($$n=6$$

n
=
6

) subjected to a protocol for fully automated computer-controlled hemodynamic drug administration. Onset of IMC within 1 h following circulatory death defined the primary end-point. Cardiac work estimates based on pressure-volume loop concepts were developed and used to provide insight into the effectiveness of the proposed computer-controlled therapy.

Results

No test group individual developed IMC within $${1} \text { h}$$

1

h

, whereas all control group individuals did (4/6 within $${30}{\text { min}}$$

30

min

).

Conclusion

Automatic dosing of hemodynamic drugs in the controlled DCD context has the potential to prevent onset of IMC up to $${1}{\text { h}}$$

1

h

, enabling ethical and medically safe organ procurement. This has the potential to increase the use of DCD heart transplantation, which has been widely recognized as a means of meeting the growing demand for donor hearts.
Mechanisms of CO2 reduction into CO and formic acid on Fe (100): a DFT study
Authors: Kwawu Caroline R. , Aniagyei Albert , Konadu Destiny , Antwi Boniface Yeboah
Published: April 2021

Understanding the mechanism of CO2 reduction on iron is crucial for the design of more efficient and cheaper iron electrocatalyst for CO2 conversion. In the present study, we have employed spin-polarized density functional theory calculations within the generalized gradient approximation (DFT-GGA) to elucidate the mechanism of CO2 reduction into carbon monoxide and formic acid on the Fe (100) facet. We also sort to understand the transformations of the other isomers of adsorbed CO2 on iron as earlier mechanistic studies are centred on the transformations of the C2v geometry alone and not the other possible conformations i.e., flip-C2v and Cs modes. Two alternative reduction routes were considered i.e., the direct CO2 dissociation against the hydrogen-assisted CO2 transformation through formate and carboxylate into CO and formic acid. Our results show that CO2 in the C2v mode is the precursor to the formation of both products i.e., CO and formic acid. Both the formation and transformation of CO2 in the Cs and flip-C2v is challenging kinetically and thermodynamically compared to the C2v mode. The formic acid formation is favoured over CO via the reverse water gas shift reaction mechanism on Fe (100). Both formic acid formation and CO formation will proceed via the carboxylate intermediate since formate is a stable intermediate whose transformation into formic acid is challenging both kinetically and thermodynamically.

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Influence of two polyphenols on the structure and lubrication of salivary pellicle: An in vitro study on astringency mechanism
Authors: Lei Lei , Tang Yue , Zheng Jing , Ma Genlei , Zhou Zhongrong
Published: April 2021

This study investigated the influence of two polyphenols on the structure and lubrication of the salivary pellicle, aiming to extend the understanding of astringency mechanisms. The salivary pellicle was prepared by the adsorption of human whole saliva on the enamel substrate. Low-astringency catechin and high-astringency tannic acid were used as astringents. The changes induced by the two polyphenols in the structure and lubrication of the salivary pellicle were examined using quartz crystal microbalance with dissipation (QCM-D) and nano-indentation/scratch technique. The salivary pellicle suffers from changes in structure and physical properties owing to protein dehydration and protein-polyphenol complexation when encountering polyphenolic molecules, causing increases in the roughness and contact angle but a decrease in the load-bearing capacity. Therefore, the lubrication performance of the salivary pellicle is impaired, leading to an increase and fluctuation of the friction coefficient. The intensity of astringency has a strong positive correlation with the water contact angle, surface roughness, and friction coefficient of the salivary pellicle. In summary, astringency is a tactile perception driven by the roughness and wettability of the salivary pellicle rather than oral lubrication, and increased intraoral friction is an inevitable consequence of astringency. The findings of this study will help promote and assist the objective evaluation of astringency.
Efficient Personalized Influential Community Search in Large Networks
Authors: Wu Yanping , Zhao Jun , Sun Renjie , Chen Chen , Wang Xiaoyang
Published: April 2021

Community search, which aims to retrieve important communities (i.e., subgraphs) for a given query vertex, has been widely studied in the literature. In the recent, plenty of research is conducted to detect influential communities, where each vertex in the network is associated with an influence value. Nevertheless, there is a paucity of work that can support personalized requirement. In this paper, we propose a new problem, i.e., maximal personalized influential community search. Given a graph G, an integer k and a query vertex u, we aim to obtain the most influential community for u by leveraging the k-core concept. To handle larger networks efficiently, two algorithms, i.e., top-down algorithm and bottom-up algorithm, are developed. In real-life applications, there may be a lot of queries issued. Therefore, an optimal index-based approach is proposed in order to meet the online requirement. In many scenarios, users may want to find multiple communities for a given query. Thus, we further extend the proposed techniques for the top-r case, i.e., retrieving r communities with the largest influence value for a given query. Finally, we conduct extensive experiments on 6 real-world networks to demonstrate the advantage of proposed techniques.
BODIPY-based fluorescent polymeric probes for selective detection of Fe3+ ions in aqueous solution
Authors: Xiao Li , Li Chunqing , He Xiantinglv , Cheng Xinjian
Published: April 2021

It is of scientific and practical significance to sense and to remove heavy metal ions in the environment. In this work, four BODIPY-based fluorescent polymeric probes with the ability to sense and separate Fe3+ ions have been prepared via thiol-ene click reaction. The polymers have good thermal stability. Meanwhile, the results show that they have selective recognition capabilities only for Fe3+, which are mainly manifested as significant quenching of fluorescence and color modulation under visible light. The sensitivity is good, and the limit of detection reaches as low as 0.14 µM. They can also be used as reversible chemical probes to detect Fe3+. Therefore, the click reaction provides us with a facile method for preparing fluorescent polymer probes.
Modular Approach to Ultra-fast Charging Stations
Authors: Leone Carola , Longo Michela
Published: April 2021

Road transport electrification is essential for meeting the European Union's goals of decarbonization and climate change. In this context, an Ultra-Fast Charging (UFC) system is deemed necessary to facilitate the massive penetration of Electric Vehicles (EVs) on the market; particularly as medium-long distance travels are concerned. Anyway, an ultra-fast charging infrastructure represents the most critical point as regards hardware technology, grid-related issues, and financial sustainability. Thus far, this paper presents an impact analysis of a fast-charging station on the grid in terms of power consumption, obtained by the Monte Carlo simulation. Simulation results show that it is not economical convenient size the assumed ultra-fast charging station for the maximum possible power also considering its high impact on the grid. In view of the results obtained from the impact analysis, the last part of the paper focuses on finding a method to reduce the power installed for the DC/DC stage while keeping the possibility for the electric vehicle to charge at their maximum power. To achieve this goal a modular approach is proposed. Finally, two different modular architectures are presented and compared. In both the solutions, the probability of having EVs charging at limited power is less than 5%.
The performance of ultra-lightweight foamed concrete incorporating nanosilica
Authors: Abd Elrahman Mohamed , Sikora Pawel , Chung Sang-Yeop , Stephan Dietmar
Published: April 2021

This paper aims to investigate the feasibility of the incorporation of nanosilica (NS) in ultra-lightweight foamed concrete (ULFC), with an oven-dry density of 350 kg/m3, in regard to its fresh and hardened characteristics. The performance of various dosages of NS, up to 10 wt.-%, were examined. In addition, fly ash and silica fume were used as cement replacing materials, to compare their influence on the properties of foamed concrete. Mechanical and physical properties, drying shrinkage and the sorption of concrete were measured. Scanning electron microscopy (SEM) and X-ray microcomputed tomography (µ-CT) and a probabilistic approach were implemented to evaluate the microstructural changes associated with the incorporation of different additives, such as wall thickness and pore anisotropy of produced ULFCs. The experimental results confirmed that the use of NS in optimal dosage is an effective way to improve the stability of foam bubbles in the fresh state. Incorporation of NS decrease the pore anisotropy and allows to produce a foamed concrete with increased wall thickness. As a result more robust and homogenous microstructure is produced which translate to improved mechanical and transport related properties. It was found that replacement of cement with 5 wt.-% and 10 wt.-% NS increase the compressive strength of ULFC by 20% and 25%, respectively, when compared to control concrete. The drying shrinkage of the NS-incorporated mixes was higher than in the control mix at early ages, while decreasing at 28 d. In overall, it was found that NS is more effective than other conventional fine materials in improving the stability of fresh mixture as well as enhancing the strength of foamed concrete and reducing its porosity and sorption.
Law and Philosophy in the Late Roman Republic
Authors: Brouwer René
Published: April 2021

The middle of the second until the middle of the first century BCE is one of the most creative periods in the history of human thought, and an important part of this was the interaction between Roman jurists and Hellenistic philosophers. In this highly original book, René Brouwer shows how jurists transformed the study of law into a science with the help of philosophical methods and concepts, such as division, rules and persons, and also how philosophers came to share the jurists' preoccupations with cases and private property. The relevance of this cross-fertilization for present-day law and philosophy cannot be overestimated: in law, its legacy includes the academic study of law and the Western models of dispute resolution, while in philosophy, the method of casuistry and the concept of just property.