bluuebunny/crossref_metadata_2025 huggingface dataset:
The Galician Canal—An unrealized project that changed the rivers in the northern part of the Carpathians
Authors: Witkowski Karol
Published: August 2021

The article presents the history and the impact of the Galician Canal project on the natural environment. In order to identify the relationship between political and economic decisions and the transformation of the natural environment, the Water System Concept was used. The canal was designed in Galicia belonging to the Austro‐Hungarian Empire. The central government in Vienna decided to build a network of waterways in 1901. In Galicia, it was expected that this project would lead to economic development, which was dependent on export opportunities. The canal project assumed the construction of a canal connecting the Oder with the Vistula and the Dniester. An integral element of the project was also the regulation of the rivers, which was to enable the control of the canal's supply with water and bed‐load. After the collapse of the Empire, most of the canal was located in the territory of Poland. Repeated design changes meant that construction work on the canal was progressing slowly. Ultimately, the construction of the canal was abandoned, but the river regulation was completed. The canal is, therefore, an example of an unrealized project that significantly affected the natural environment. River regulation destroyed the multi‐thread channel pattern and triggered the channel incision process. The transformation of multi‐thread rivers to single‐thread ones resulted in a reduction in biodiversity. The Carpathian rivers would never have been channelized to such a large extent had it not been for the canal project.
A tutorial on individualized treatment effect prediction from randomized trials with a binary endpoint
Authors: Hoogland Jeroen , IntHout Joanna , Belias Michail , Rovers Maroeska M. , Riley Richard D. , E. Harrell Jr Frank , Moons Karel G. M. , Debray Thomas P. A. , Reitsma Johannes B.
Published: August 2021

Randomized trials typically estimate average relative treatment effects, but decisions on the benefit of a treatment are possibly better informed by more individualized predictions of the absolute treatment effect. In case of a binary outcome, these predictions of absolute individualized treatment effect require knowledge of the individual's risk without treatment and incorporation of a possibly differential treatment effect (ie, varying with patient characteristics). In this article, we lay out the causal structure of individualized treatment effect in terms of potential outcomes and describe the required assumptions that underlie a causal interpretation of its prediction. Subsequently, we describe regression models and model estimation techniques that can be used to move from average to more individualized treatment effect predictions. We focus mainly on logistic regression‐based methods that are both well‐known and naturally provide the required probabilistic estimates. We incorporate key components from both causal inference and prediction research to arrive at individualized treatment effect predictions. While the separate components are well known, their successful amalgamation is very much an ongoing field of research. We cut the problem down to its essentials in the setting of a randomized trial, discuss the importance of a clear definition of the estimand of interest, provide insight into the required assumptions, and give guidance with respect to modeling and estimation options. Simulated data illustrate the potential of different modeling options across scenarios that vary both average treatment effect and treatment effect heterogeneity. Two applied examples illustrate individualized treatment effect prediction in randomized trial data.
Synthesis, Structure‐Activity Relationship and in silico Studies of Novel Pyrazolothiazole and Thiazolopyridine Derivatives as Prospective Antimicrobial and Anticancer Agents
Authors: Othman Ismail M. M. , Gad‐Elkareem Mohamed A. M. , Radwan Hyam A. , Badraoui Riadh , Aouadi Kaïss , Snoussi Mejdi , Kadri Adel
Published: August 2021

In our attempt to develop potential new drug candidates with promising dual antimicrobial and anticancer activities, a series of pyrazolothiazole and thiazolopyridine analogues has been synthesized. All compounds were evaluated for their antimicrobial potential towards pathogenic strains and cytotoxicity properties against hepatic cancer cell line HepG‐2 and breast cancer cell line MCF‐7. 9 c showed excellent antimicrobial activity against the tested strains, with MIC values about 27.5 μM (S. epidermidis), 6.8 (B. subtilis) and 3.4 μM (S. pneumoniae and K. pneumoniae) fold higher than the reference drug, whilst 9 a, 9 b and 5 a exhibited also potent activity against selected strains. Moreover, compounds 9 c (IC50=10.89 μM and 15.60 μM) and 9 a (IC50=22.24 μM and 28.47 μM) showed promising anticancer activity for HepG2 and MCF‐7 cell lines, respectively, when compared to the known anticancer drugs, 5‐Fluorouracil (IC50=26.75 μM and IC50=32.75 μM). The data from structure‐activity relationships analysis revealed the potency of pyrazolothiazole than thiazolopyridine derivatives in generating potential activity. Further, molecular docking studies performed on the more active antimicrobial and cytotoxic compound, 9 c to get insights for binding modes to the target enzymes (PDB ID: 1JIJ) for antimicrobial, and (PDB ID: 1DI8) and (PDB ID: 3TWJ) for anticancer revealed that they interacted with the same key amino acids with TyrRS for S. aureus, CDK2 and ROCK1, respectively.
Applications of 3,5‐Dialkyl‐4‐nitroisoxazoles and Their Derivatives in Organic Synthesis#
Authors: Nagaraju Sakkani , Sathish Kota , Kashinath Dhurke
Published: August 2021

The methyl/methylene group present at the 5th position of 3,5‐dialkyl‐4‐nitroisoxazoles show characteristic reactivity because of the presence of −NO2 at the 4th position in the structure. This methyl/methylene is used for the generation of carbanion that undergo Knoevenagel condensation, vinylogous nitroaldol (Henry type), Mannich and Michael addition reactions. The unsaturated systems generated by Knoevenagel condensation are used for 1,4‐ and 1,6‐Michael addition, epoxidation, aziridination, cycloaddition ([2+1], [2+2], [2+3] and [4+2]) cascade/domino/tandem and dihydroxylation reactions. This resulted into the generation of many functionalized and complex organic molecules in asymmetric and racemic forms. Along with these, the isoxazole moiety has also been used as −COOH equivalent by basic/oxidative hydrolysis. This review describes recent literature on the synthetic applications of 3,5‐dialkyl‐4‐nitroisoxazoles and their derivatives for the generation of functionalized/complex heterocyclic compounds using above mentioned type of reactions and concepts.
Functional Supramolecular Gels Comprised of Bis‐Urea Compounds and Cosmetic Solvents
Authors: Genio Frances Abygail F. , Paderes Monissa C.
Published: August 2021

In this study, bis‐urea derivatives were found to be effective supramolecular gelators in cosmetic solvents. The structural details of the gels which showed different aggregation patterns were obtained using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The difference in the network formation of the gels suggests dependence of the self‐assembly process in the solvent and structure of the gelator. Oscillatory measurements demonstrated the elastic and solid‐like behavior of the gels, with storage modulus (G’) greater than the loss modulus (G”) at the linear viscoelastic region. The imaging and rheological analyses along with the gelation test results, indicate that the nanostructural framework and stability of the gels were also influenced by solvophobic interactions. The self‐assembling behavior of bis‐urea compounds via hydrogen bonding was qualitatively assessed by Fourier transform infrared (FTIR) spectroscopy. The organogels discussed in this study can be further explored and their properties tuned for potential use in commercial cosmetic formulations.
RNA–ligand molecular docking: Advances and challenges
Authors: Zhou Yuanzhe , Jiang Yangwei , Chen Shi‐Jie
Published: August 2021

With rapid advances in computer algorithms and hardware, fast and accurate virtual screening has led to a drastic acceleration in selecting potent small molecules as drug candidates. Computational modeling of RNA‐small molecule interactions has become an indispensable tool for RNA‐targeted drug discovery. The current models for RNA–ligand binding have mainly focused on the docking‐and‐scoring method. Accurate docking and scoring should tackle four crucial problems: (1) conformational flexibility of ligand, (2) conformational flexibility of RNA, (3) efficient sampling of binding sites and binding poses, and (4) accurate scoring of different binding modes. Moreover, compared with the problem of protein–ligand docking, predicting ligand binding to RNA, a negatively charged polymer, is further complicated by additional effects such as metal ion effects. Thermodynamic models based on physics‐based and knowledge‐based scoring functions have shown highly encouraging success in predicting ligand binding poses and binding affinities. Recently, kinetic models for ligand binding have further suggested that including dissociation kinetics (residence time) in ligand docking would result in improved performance in estimatingin vivodrug efficacy. More recently, the rise of deep‐learning approaches has led to new tools for predicting RNA‐small molecule binding. In this review, we present an overview of the recently developed computational methods for RNA–ligand docking and their advantages and disadvantages.

This article is categorized under:

Structure and Mechanism > Computational Biochemistry and Biophysics
Paul Lorenzens Weg von der Mathematik zur Philosophie - Persönliche Erinnerungen
Authors: Lorenz Kuno
Published: August 2021

Es gibt mittlerweile schon zahlreiche, auf gründlichen Recherchen und großenteils auch auf persönlichen Begegnungen beruhende Arbeiten zu den Stadien im Lebensweg Paul Lorenzens.
Conclusions
Authors: Hilsen Anne Inga , Olsen Dorothy Sutherland
Published: August 2021

We will discuss how the concept of the wise worker can be used in the workplace and how a focus on late career competence can be of value to employers, employees and policymakers. At the same time, it is important to acknowledge that age alone is not enough to ensure wisdom. We will set out some conditions to understanding and using the concept of the wise worker.
New physics from oscillations at the DUNE near detector, and the role of systematic uncertainties
Authors: Coloma Pilar , López-Pavón Jacobo , Rosauro-Alcaraz Salvador , Urrea Salvador
Published: August 2021

Abstract

We study the capabilities of the DUNE near detector to probe deviations from unitarity of the leptonic mixing matrix, the 3+1 sterile formalism and Non-Standard Interactions affecting neutrino production and detection. We clarify the relation and possible mappings among the three formalisms at short-baseline experiments, and we add to current analyses in the literature the study of the νμ→ ντ appearance channel. We study in detail the impact of spectral uncertainties on the sensitivity to new physics using the DUNE near detector, which has been widely overlooked in the literature. Our analysis shows that this plays an important role on the results and, in particular, that it can lead to a strong reduction in the sensitivity to sterile neutrinos from νμ→ νe transitions, by more than two orders of magnitude. This stresses the importance of a joint experimental and theoretical effort to improve our understanding of neutrino nucleus cross sections, as well as hadron production uncertainties and beam focusing effects. Nevertheless, even with our conservative and more realistic implementation of systematic uncertainties, we find that an improvement over current bounds in the new physics frameworks considered is generally expected if spectral uncertainties are below the 5% level.
Emergent geometry through quantum entanglement in Matrix theories
Authors: Gray Cameron , Sahakian Vatche , Warfield William
Published: August 2021

Abstract

In the setting of the Berenstein-Maldacena-Nastase Matrix theory, dual to light-cone M-theory in a PP-wave background, we compute the Von Neumann entanglement entropy between a probe giant graviton and a source. We demonstrate that this entanglement entropy is directly and generally related to the local tidal acceleration experienced by the probe. This establishes a new map between local spacetime geometry and quantum entanglement, suggesting a mechanism through which geometry emerges from Matrix quantum mechanics. We extend this setting to light-cone M-theory in flat space, or the Banks-Fischler-Shenker-Susskind Matrix model, and we conjecture a new general relation between a certain measure of entanglement in Matrix theories and local spacetime geometry. The relation involves a ‘c-tensor’ that measures the evolution of local transverse area and relates to the local energy-momentum tensor measured by a probe.
Axion/hidden-photon dark matter conversion into condensed matter axion
Authors: Chigusa So , Moroi Takeo , Nakayama Kazunori
Published: August 2021

Abstract

The QCD axion or axion-like particles are candidates of dark matter of the universe. On the other hand, axion-like excitations exist in certain condensed matter systems, which implies that there can be interactions of dark matter particles with condensed matter axions. We discuss the relationship between the condensed matter axion and a collective spin-wave excitation in an anti-ferromagnetic insulator at the quantum level. The conversion rate of the light dark matter, such as the elementary particle axion or hidden photon, into the condensed matter axion is estimated for the discovery of the dark matter signals.
Babai’s conjecture for high-rank classical groups with random generators
Authors: Eberhard Sean , Jezernik Urban
Published: August 2021

Let $$G = {\text {SCl}}_n(q)$$

G
=

SCl
n

(
q
)

be a quasisimple classical group with n large, and let $$x_1, \ldots , x_k \in G$$

x
1

,
…
,

x
k

∈
G

be random, where $$k \ge q^C$$

k
≥

q
C

. We show that the diameter of the resulting Cayley graph is bounded by $$q^2 n^{O(1)}$$

q
2

n

O
(
1
)

with probability $$1 - o(1)$$

1
-
o
(
1
)

. In the particular case $$G = {\text {SL}}_n(p)$$

G
=

SL
n

(
p
)

with p a prime of bounded size, we show that the same holds for $$k = 3$$

k
=
3

.
A safety study of laparoscopic single-anastomosis duodeno-ileal bypass with gastric plication (SADI-GP) in the management of morbid obesity
Authors: Balint Istvan Bence , Csaszar Ferenc , Orban Lajos , Radics Peter , Farics Akos , Manfai Gergo , Hari Veronika , Javor Rebeka
Published: August 2021

Background

Bariatric surgery is more effective in the management of morbid obesity and related comorbidities than is conservative therapy. Pylorus-preserving single-anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-SG) is a modified duodenal switch technique. Gastric plication (GP) is an alternate to SG.

Methods

Morbidly obese (BMI of > 40, or > 35 in the presence of diabetes or prediabetes) patients were recruited and operated on to perform SADI with GP. Complications related to surgery were recorded to assess the feasibility of the procedure. Weight-loss outcomes were analysed to determine efficacy. Minnesota Multiphasic Personality Inventory 2 (MMPI-2) was recorded after 1 year of follow-up, and test scales were used to describe physiological phenomena.

Results

Seventeen middle-aged (mean: 40 years) patients were involved in our study; 15 of them were females. The mean duration of surgery was 205 min. There were no complications of conversion, death, bleeding, VTE or 30-day readmission to hospital. We did experience CD4a (pulmonary insufficiency due to chronic lung disease) and a CD3b (anastomosis leakage treated laparoscopically) complications. Vomiting occurred in three cases (CD1). Obesity-related comorbidities showed favourable resolution rates (77.8% for hypertension, 81.2% for dyslipidaemia, 100% for diabetes at the 1-year follow-up). Weight-loss outcomes were favourable (53.20 EWL%, and 35.58 TWL% at 1-year follow-up). Greater weight loss caused significantly higher levels of Depression (t(13.958) =  − 2.373; p = 0.00; p < 0.05) and Low Positive Emotions (t(13.301) =  − 2.954; p = 0.00; p < 0.05) and Introversion/Low Positive Emotionality (t(13.408) =  − 1.914; p = 0.02; p < 0.05) in MMPI-2 data.

Conclusion

According to our safety study, SADI-GP is a promising malabsorptive procedure, but a long-term high-volume case series or a randomised controlled trial is necessary to evaluate complication rates and weight-loss outcomes. Emotional dysregulation is common among bariatric surgery patients according to personality inventory data; therefore, psychological follow-up and psychotherapeutic support are necessary for weight-loss maintenance.
Mathematical political districting taking care of minority groups
Authors: Arredondo Verónica , Martínez-Panero Miguel , Peña Teresa , Ricca Federica
Published: August 2021

Political districting (PD) is a wide studied topic in the literature since the 60s. It typically requires a multi-criteria approach, and mathematical programs are frequently suggested to model the many aspects of this difficult problem. This implies that exact models cannot be solved to optimality when the size of the territory is too large. In spite of this, an exact formulation can also be exploited in a heuristic framework to find at least a sub-optimal solution for large size problem instances. We study the design of electoral districts in Mexico, where the population is characterized by the presence of minority groups (“indigenous community”) who have a special right to be represented in the Parliament. For this, the Mexican electoral law prescribes that a fixed number of districts must be designed to support the representation of the indigenous community. We formulate mixed integer linear programs (MILP) following these two principles, but also including the basic PD criteria of contiguity and population balance. The district map is obtained in two stages: first we produce the fixed number of indigenous districts established by the Law; then we complete the district map by forming the non-indigenous districts. This two-phase approach has two advantages: a dedicated objective function can be formulated in Phase 1 to form indigenous districts at best; in the second phase the instance size is reduced (both in the number of territorial units and in the number of districts) so that the computational effort to solve the problem is reduced as well. We test our procedure on the territory of Chiapas in Mexico and on some fictitious problem instances in which the territory is represented by a grid graph. We also compare our district map with the Institutional one currently adopted in Chiapas.
A day at the races
Authors: Losada David E. , Elsweiler David , Harvey Morgan , Trattner Christoph
Published: August 2021

Two major barriers to conducting user studies are the costs involved in recruiting participants and researcher time in performing studies. Typical solutions are to study convenience samples or design studies that can be deployed on crowd-sourcing platforms. Both solutions have benefits but also drawbacks. Even in cases where these approaches make sense, it is still reasonable to ask whether we are using our resources – participants’ and our time – efficiently and whether we can do better. Typically user studies compare randomly-assigned experimental conditions, such that a uniform number of opportunities are assigned to each condition. This sampling approach, as has been demonstrated in clinical trials, is sub-optimal. The goal of many Information Retrieval (IR) user studies is to determine which strategy (e.g., behaviour or system) performs the best. In such a setup, it is not wise to waste participant and researcher time and money on conditions that are obviously inferior. In this work we explore whether Best Arm Identification (BAI) algorithms provide a natural solution to this problem. BAI methods are a class of Multi-armed Bandits (MABs) where the only goal is to output a recommended arm and the algorithms are evaluated by the average payoff of the recommended arm. Using three datasets associated with previously published IR-related user studies and a series of simulations, we test the extent to which the cost required to run user studies can be reduced by employing BAI methods. Our results suggest that some BAI instances (racing algorithms) are promising devices to reduce the cost of user studies. One of the racing algorithms studied, Hoeffding, holds particular promise. This algorithm offered consistent savings across both the real and simulated data sets and only extremely rarely returned a result inconsistent with the result of the full trial. We believe the results can have an important impact on the way research is performed in this field. The results show that the conditions assigned to participants could be dynamically changed, automatically, to make efficient use of participant and experimenter time.
Comparison of the electrical conductivity of bulk and film Ce1–xZrxO2–δ in oxygen-depleted atmospheres at high temperatures
Authors: Kogut Iurii , Steiner Carsten , Wulfmeier Hendrik , Wollbrink Alexander , Hagen Gunter , Moos Ralf , Fritze Holger
Published: August 2021

Featuring high levels of achievable oxygen non-stoichiometry δ, Ce1−xZrxO2−δ solid solutions (CZO) are crucial for application as oxygen storage materials in, for example, automotive three-way catalytic converters (TWC). The use of CZO in form of films combined with simple manufacturing methods is beneficial in view of device miniaturization and reducing of TWC manufacturing costs. In this study, a comparative microstructural and electrochemical characterization of film and conventional bulk CZO is performed using X-ray diffractometry, scanning electron microscopy, and impedance spectroscopy. The films were composed of grains with dimensions of 100 nm or less, and the bulk samples had about 1 µm large grains. The electrical behavior of nanostructured films and coarse-grained bulk CZO (x > 0) was qualitatively similar at high temperatures and under reducing atmospheres. This is explained by dominating effect of Zr addition, which masks microstructural effects on electrical conductivity, enhances the reducibility, and favors strongly electronic conductivity of CZO at temperatures even 200 K lower than those for pure ceria. The nanostructured CeO2 films had much higher electrical conductivity with different trends in dependence on temperature and reducing atmospheres than their bulk counterparts. For the latter, the conductivity was dominantly electronic, and microstructural effects were significant at T < 700 °C. Nanostructural peculiarities of CeO2 films are assumed to induce their more pronounced ionic conduction at medium oxygen partial pressures and relatively low temperatures. The defect interactions in bulk and film CZO under reducing conditions are discussed in the framework of conventional defect models for ceria.
“Living Between Two Different Worlds”: Experiences of Leaving a High-Cost Religious Group
Authors: Björkmark Maria , Nynäs Peter , Koskinen Camilla
Published: August 2021

The aim of this interdisciplinary study is to gain a comprehensive understanding of individuals’ subjective experiences after leaving a high-cost religious group and how these experiences have affected their lives. In-depth interviews were done with 18 participants who had left different religious communities in Finland. The interviews were analysed through a thematic analysis. The results show that religious disaffiliation is a life change that may affect an individual’s life in profound ways. Life after being a member of a high-cost group may involve experiences of fear, guilt, sorrow, pain, loss and even suffering on an existential level. These experiences can have serious implications for one’s well-being and health. However, life after religious disaffiliation also includes many positive aspects, such as experiences of joy, freedom, relief, gratitude and empowerment.
Gradient-Based Training of Gaussian Mixture Models for High-Dimensional Streaming Data
Authors: Gepperth Alexander , Pfülb Benedikt
Published: August 2021

We present an approach for efficiently training Gaussian Mixture Model (GMM) by Stochastic Gradient Descent (SGD) with non-stationary, high-dimensional streaming data. Our training scheme does not require data-driven parameter initialization (e.g., k-means) and can thus be trained based on a random initial state. Furthermore, the approach allows mini-batch sizes as low as 1, which are typical for streaming-data settings. Major problems in such settings are undesirable local optima during early training phases and numerical instabilities due to high data dimensionalities. We introduce an adaptive annealing procedure to address the first problem, whereas numerical instabilities are eliminated by an exponential-free approximation to the standard GMM log-likelihood. Experiments on a variety of visual and non-visual benchmarks show that our SGD approach can be trained completely without, for instance, k-means based centroid initialization. It also compares favorably to an online variant of Expectation-Maximization (EM)—stochastic EM (sEM), which it outperforms by a large margin for very high-dimensional data.
Numerical solution for an inverse variational problem
Authors: Garralda-Guillem A. I. , Montiel López P.
Published: August 2021

In the present work, firstly, we use a minimax equality to prove the existence of a solution to a certain system of varitional equations providing a numerical approximation of such a solution. Then, we propose a numerical method to solve a collage-type inverse problem associated with the corresponding system, and illustrate the behaviour of the method with a numerical example.
Intrapersonal variability in public transport path choice due to changes in service reliability
Authors: Berggren Ulrik , D’Agostino Carmelo , Svensson Helena , Brundell-Freij Karin
Published: August 2021

Uncertainty during the course of a trip is regarded as a particularly disturbing phenomenon by public transport (PT) passengers and has been shown to have a substantial impact on travel behaviour. However, so far there has been little empirical evidence within contemporary research concerning the degree of mid- to long-term adaptation among PT passengers to changes in the principal cause of such uncertainty within PT transport systems: Lack of service departure reliability. While most studies to date have focussed on instantaneous or short-term behavioural responses, this paper presents results from a one-year panel dataset consisting of individuals’ trip itineraries derived from smart card transactions enriched by automatic vehicle location (AVL) data. We measured long-term line route usage and departure reliability, the latter in terms of headway regularity and schedule adherence, in two panel waves. Thus, we aimed for practical indicators that may be associated with specific line routes and origin–destination PT stop pairs used for recurring trips over time. Results from logistic regression indicate a consistent significant impact of changed headway regularity and punctuality change for line routes with relatively high departure frequency. However, there is a relative indifference to long-term reliability change by a significant share of individuals that have actual trade-offs between at least two line route options, possibly indicating satisficing behaviour among PT passengers. Implications on PT path choice forecasting and route planning are discussed.
Deep calibration of financial models: turning theory into practice
Authors: Büchel Patrick , Kratochwil Michael , Nagl Maximilian , Rösch Daniel
Published: August 2021

The calibration of financial models is laborious, time-consuming and expensive, and needs to be performed frequently by financial institutions. Recently, the application of artificial neural networks (ANNs) for model calibration has gained interest. This paper provides the first comprehensive empirical study on the application of ANNs for calibration based on observed market data. We benchmark the performance of the ANN approach against a real-life calibration framework that is in action at a large financial institution. The ANN based calibration framework shows competitive calibration results, roughly four times faster with less computational efforts. Besides speed and efficiency, the resulting model parameters are found to be more stable over time, enabling more reliable risk reports and business decisions. Furthermore, the calibration framework involves multiple validation steps to counteract regulatory concerns regarding its practical application.
Learning with Friction—Students’ Gestures and Enactment in Relation to a GeoGebra Simulation
Authors: Solvang Lorena , Haglund Jesper
Published: August 2021

The present study contributes to the understanding of physics students’ representational competence by examining specific bodily practices (e.g. gestures, enactment) of students’ interaction and constructions of representations in relation to a digital learning environment. We present and analyse video data of upper-secondary school students’ interaction with a GeoGebra simulation of friction. Our analysis is based on the assumption that, in a collaborative learning environment, students use their bodies as means of dealing with interpretational problems, and that exploring students’ gestures and enactment can be used to analyse their sensemaking processes. This study shows that specific features of the simulation—features connected with microscopic aspects of friction—triggered students to ask what-if and why questions and consequently, to learn about the representation. During this sense-making process, students improvised their own representations to make their ideas more explicit. The findings extend current research on students’ representational competence by bringing attention to the role of students’ generation of improvised representations in the processes of learning with and about representations.
A Comprehensive Taxonomy of Tasks for Assessing the Impact of New Technologies on Work
Authors: Fernández-Macías Enrique , Bisello Martina
Published: August 2021

In recent years, the increasing concern about the labour market implications of technological change has led economists to look in more detail at the structure of work content and job tasks. Incorporating insights from other traditions of task analysis, in particular from the labour process approach, as well as from recent research on skills, work organisation and occupational change, in this paper we propose a comprehensive and detailed taxonomy of tasks. Going beyond existing broad classifications, our taxonomy aims at connecting the substantive content of work with its organisational context by answering two key questions: what do people do at work and how do they do their work? For illustrative purposes, we show how our approach allows a better understanding of the impact of new technologies on work, by accounting for relevant ongoing transformations such as the diffusion of artificial intelligence and the unfolding of digital labour platforms.
Ethnographies of Volunteering: Providing Nuance to the Links Between Volunteering and Development
Authors: Chadwick Alice , Fadel Bianca , Millora Chris
Published: August 2021

This paper explores how ethnographic approaches to third sector and nonprofit studies allow for context-based understandings of the links between volunteering and development. Drawing from our ethnographies of volunteering in Sierra Leone, Burundi and the Philippines, we argue that ethnographic methods could tease out local ideologies and practices of volunteer work that can challenge knowledge monopolies over how volunteering is understood and, later, transcribed into development policy and practice at various levels. The contribution of ethnography as a methodology to third sector research lies not only in the in-depth data it generates but also in the kind of ethos and disposition it requires of scholars—providing attention to issues of power and voice and leaning into the unpredictability of the research process.
For the Love of Art? Episodic Volunteering at Cultural Events
Authors: Hersberger-Langloh Sophie E. , von Schnurbein Georg , Kang Chulhee , Almog-Bar Michal , García-Colín Jacqueline Butcher , García Marta Rey
Published: August 2021

Although episodic volunteering is a popular form of volunteering and has received increasing attention from researchers, the motives and characteristics of episodic volunteers in different industries or types of events remain underresearched, especially in the context of cultural events. This study is based on a sample of more than 2000 episodic volunteers and analyzes demographic characteristics, motives, and volunteer experience of cultural event volunteers by applying between and within analysis. The between analysis compares cultural and social event volunteers and finds that cultural event volunteers show higher time engagement but are more self-serving in their motives. The within analysis emphasizes intrinsic motives over extrinsic motives, leading to the conclusion that saturation of extrinsic motives reduces willingness for future engagements.
Optimized Doxycycline-Inducible Gene Expression System for Genetic Programming of Tumor-Targeting Bacteria
Authors: Nguyen Dinh-Huy , You Sung-Hwan , Vo An-Trang Ngoc , Ngo Hien Thi-Thu , Van Nguyen Khuynh , Duong Mai Thi-Quynh , Choy Hyon E. , Song Miryoung , Hong Yeongjin , Min Jung-Joon
Published: August 2021

Purpose

In the programming of tumor-targeting bacteria, various therapeutic or reporter genes are expressed by different gene-triggering strategies. Previously, we engineered pJL87 plasmid with an inducible bacterial drug delivery system that simultaneously co-expressed two genes for therapy and imaging by a bidirectional tet promoter system only in response to the administration of exogenous doxycycline (Doxy). In this multi-cassette expression approach, tetA promoter (PtetA) was 100-fold higher in expression strength than tetR promoter (PtetR). In the present study, we developed pJH18 plasmid with novel Doxy-inducible gene expression system based on a tet promoter.

Procedures

In this system, Tet repressor (TetR) expressed by a weak constitutive promoter binds to tetO operator, resulting in the tight repression of gene expressions by PtetA and PtetR, and Doxy releases TetR from tetO to de-repress PtetA and PtetR.

Results

In Salmonella transformed with pJH18, the expression balance of bidirectional tet promoters in pJH18 was remarkably improved (PtetA:PtetR = 4~6:1) compared with that of pJL87 (PtetA:PtetR = 100:1) in the presence of Doxy. Also, the expression level by novel tet system was much higher in Salmonella transformed with pJH18 than in those with pJL87 (80-fold in rluc8 and 5-fold in clyA). Interestingly, pJH18 of the transformed Salmonella was much more stably maintained than pJL87 in antibiotic-free tumor-bearing mice (about 41-fold), because only pJH18 carries bom sequence with an essential role in preventing the plasmid-free population of programmed Salmonella from undergoing cell division.

Conclusions

Overall, doxycycline-induced co-expression of two proteins at similar expression levels, we exploited bioluminescence reporter proteins with preclinical but no clinical utility. Future validation with clinically compatible reporter systems, for example, suitable for radionuclide imaging, is necessary to develop this system further towards potential clinical application.
Migraine and Cochlear Symptoms
Authors: Ma Xin , Ke Yu-jie , Jing Yuan-yuan , Diao Tong-xiang , Yu Li-sheng
Published: August 2021

Migraine is one of the most common and highest burdens of disease. As a primary cerebral dysfunction illness, migraine might exhibit other system-related symptoms, including vestibular and cochlear symptoms. With the publication of the diagnostic criteria of vestibular migraine, the link between migraine and vestibular symptoms became clear. However, the relationship between migraine and cochlear symptoms is far from straightforward. Therefore, we focus on the correlation between migraine and deafness, sudden sensorineural hearing loss, acute tinnitus, and chronic tinnitus to better understand the relationship between migraine and cochlear symptoms.
A Brief History of Cerebellar Neurostimulation
Authors: Ponce Gustavo V. , Klaus Jana , Schutter Dennis J. L. G.
Published: August 2021

The first attempts at using electric stimulation to study human brain functions followed the experiments of Luigi Galvani and Giovanni Aldini on animal electricity during the eighteenth century. Since then, the cerebellum has been among the areas that have been studied by invasive and non-invasive forms of electrical and magnetic stimulation. During the nineteenth century, animal experiments were conducted to map the motor-related regions of cerebellar cortex by means of direct electric stimulation. As electric stimulation research on the cerebellum moved into the twentieth century, systematic research of electric cerebellar stimulation led to a better understanding of its effects and mechanism of action. In addition, the clinical potential of cerebellar stimulation in the treatment of motor diseases started to be explored. With the introduction of transcranial electric and magnetic stimulation, cerebellar research moved to non-invasive techniques. During the twenty-first century, following on groundbreaking research that linked the cerebellum to non-motor functions, non-invasive techniques have facilitated research into different aspects of cerebellar functioning. The present review provides a brief historical account of cerebellar neurostimulation and discusses current challenges and future direction in this field of research.
Influence of the Upstream Terrain on the Formation of a Cold Frontal Snowband in Northeast China
Authors: Li Na , Jiao Baofeng , Ran Lingkun , Gao Zongting , Gao Shouting
Published: August 2021

We investigated the influence of upstream terrain on the formation of a cold frontal snowband in Northeast China. We conducted numerical sensitivity experiments that gradually removed the upstream terrain and compared the results with a control experiment. Our results indicate a clear negative effect of upstream terrain on the formation of snowbands, especially over large-scale terrain. By thoroughly examining the ingredients necessary for snowfall (instability, lifting and moisture), we found that the release of mid-level conditional instability, followed by the release of low-level or near surface instabilities (inertial instability, conditional instability or conditional symmetrical instability), contributed to formation of the snowband in both experiments. The lifting required for the release of these instabilities was mainly a result of frontogenetic forcing and upper gravity waves. However, the snowband in the control experiment developed later and was weaker than that in the experiment without upstream terrain. Two factors contributed to this negative topographic effect: (1) the mountain gravity waves over the upstream terrain, which perturbed the frontogenetic circulation by rapidly changing the vertical motion and therefore did not favor the release of instabilities in the absence of persistent ascending motion; and (2) the decrease in the supply of moisture as a result of blocking of the upstream terrain, which changed both the moisture and instability structures leeward of the mountains. A conceptual model is presented that shows the effects of the instabilities and lifting on the development of cold frontal snowbands in downstream mountains.
Cancer biology deciphered by single-cell transcriptomic sequencing
Authors: Li Yanmeng , Jin Jianshi , Bai Fan
Published: August 2021

Tumors are complex ecosystems in which heterogeneous cancer cells interact with their microenvironment composed of diverse immune, endothelial, and stromal cells. Cancer biology had been studied using bulk genomic and gene expression profiling, which however mask the cellular diversity and average the variability among individual molecular programs. Recent advances in single-cell transcriptomic sequencing have enabled a detailed dissection of tumor ecosystems and promoted our understanding of tumorigenesis at single-cell resolution. In the present review, we discuss the main topics of recent cancer studies that have implemented single-cell RNA sequencing (scRNA-seq). To study cancer cells, scRNA-seq has provided novel insights into the cancer stem-cell model, treatment resistance, and cancer metastasis. To study the tumor microenvironment, scRNA-seq has portrayed the diverse cell types and complex cellular states of both immune and non-immune cells interacting with cancer cells, with the promise to discover novel targets for future immunotherapy.
Tribological performance and scuffing behaviors of several automobile piston rings mating with chrome-plated cylinder liner
Authors: Ma Zeyu , Huang Ruoxuan , Yuan Xiaoshuai , Shen Yan , Xu Jiujun
Published: August 2021

The friction and wear properties, as well as the scuffing resistance, of different piston-ring coatings mating with a chrome-plated cylinder liner were investigated. Interrupted wear tests under the lubricant starvation condition were conducted to examine the wear behavior of Cr-diamond coating (GDC) and diamond-like coating (DLC). The results indicated that the DLC coating had outstanding tribological properties (small coefficient of friction and wear loss) at 150 °C, while the GDC coating exhibited better performance at an elevated temperature (240 °C). The DLC coating had a better scuffing resistance; no material adhesion occurred for 70 min under the unlubricated condition. The interrupted wear behaviors revealed that the scuffing process of the GDC coating involved the consumption of lubricant oil with relatively stable wear, a reduction in the friction force, and the occurrence of scuffing, in sequence. In contrast, although the friction force also increased after a short period of weak friction, no scuffing was observed. This is attributed to the formation of a mixed oxide and graphitic C tribolayer.
Online distributed tracking of generalized Nash equilibrium on physical networks
Authors: Su Yifan , Liu Feng , Wang Zhaojian , Mei Shengwei , Lu Qiang
Published: August 2021

In generalized Nash equilibrium (GNE) seeking problems over physical networks such as power grids, the enforcement of network constraints and time-varying environment may bring high computational costs. Developing online algorithms is recognized as a promising method to cope with this challenge, where the task of computing system states is replaced by directly using measured values from the physical network. In this paper, we propose an online distributed algorithm via measurement feedback to track the GNE in a time-varying networked resource sharing market. Regarding that some system states are not measurable and measurement noise always exists, a dynamic state estimator is incorporated based on a Kalman filter, rendering a closed-loop dynamics of measurement-feedback driven online algorithm. We prove that, with a fixed step size, this online algorithm converges to a neighborhood of the GNE in expectation. Numerical simulations validate the theoretical results.
Model predictive control for autonomous ground vehicles: a review
Authors: Yu Shuyou , Hirche Matthias , Huang Yanjun , Chen Hong , Allgöwer Frank
Published: August 2021

This paper reviews model predictive control (MPC) and its wide applications to both single and multiple autonomous ground vehicles (AGVs). On one hand, MPC is a well-established optimal control method, which uses the predicted future information to optimize the control actions while explicitly considering constraints. On the other hand, AGVs are able to make forecasts and adapt their decisions in uncertain environments. Therefore, because of the nature of MPC and the requirements of AGVs, it is intuitive to apply MPC algorithms to AGVs. AGVs are interesting not only for considering them alone, which requires centralized control approaches, but also as groups of AGVs that interact and communicate with each other and have their own controller onboard. This calls for distributed control solutions. First, a short introduction into the basic theoretical background of centralized and distributed MPC is given. Then, it comprehensively reviews MPC applications for both single and multiple AGVs. Finally, the paper highlights existing issues and future research directions, which will promote the development of MPC schemes with high performance in AGVs.
Impact of Pre-transplant Induction Therapy on Outcomes of Patients Who Undergo Autologous Stem Cell Transplantation for Mantle Cell Lymphoma in First Complete Remission ☆
Authors: Albanyan Omar , Alkassis Samer , Kim Seongho , Kin Andrew , Alavi Asif , Ayash Lois , Ratanatharathorn Voravit , Modi Dipenkumar , Uberti Joseph P. , Deol Abhinav
Published: August 2021

Mantle cell lymphoma is a rare subtype of non-Hodgkin’s lymphoma with poor prognosis and continue to be challenging to treat. The choice of first line induction regimen remains a topic of debate due paucity of clinical trials. We retrospectively evaluated 66 patients diagnosed with mantle cell lymphoma who achieved first complete response after induction chemotherapy followed by autologous stem cell transplant. Treatment groups were divided into low-intensity versus high-intensity regimens. Our data showed the intensity of induction regimen does not impact posttransplant outcomes of mantle cell lymphoma who underwent autologous stem cell transplant in first complete response.
A Theory of Bioethics
Authors: DeGrazia David , Millum Joseph
Published: August 2021

This volume offers a carefully argued, compelling theory of bioethics while eliciting practical implications for a wide array of issues including medical assistance-in-dying, the right to health care, abortion, animal research, and the definition of death. The authors' dual-value theory features mid-level principles, a distinctive model of moral status, a subjective account of well-being, and a cosmopolitan view of global justice. In addition to ethical theory, the book investigates the nature of harm and autonomous action, personal identity theory, and the 'non-identity problem' associated with many procreative decisions. Readers new to particular topics will benefit from helpful introductions, specialists will appreciate in-depth theoretical explorations and a novel take on various practical issues, and all readers will benefit from the book's original synoptic vision of bioethics. This title is also available as Open Access on Cambridge Core.
A Commercial Law of Privacy and Security for the Internet of Things
Authors: Elvy Stacy-Ann
Published: August 2021

In the Internet of Things (IoT) era, online activities are no longer limited to desktop or laptop computers, smartphones and tablets. Instead, these activities now include ordinary tasks, such as using an internet-connected refrigerator or washing machine. At the same time, the IoT provides unlimited opportunities for household objects to serve as surveillance devices that continually monitor, collect and process vast quantities of our data. In this work, Stacy-Ann Elvy critically examines the consumer ramifications of the IoT through the lens of commercial law and privacy and security law. The book provides concrete legal solutions to remedy inadequacies in the law that will help usher in a more robust commercial law of privacy and security that protects consumer interests.