bluuebunny/crossref_metadata_2025 huggingface dataset:
Linearly monotonic convergence of nonlinear parameter‐optimal iterative learning control to linear discrete‐time‐invariant systems
Authors: Liu Yan , Ruan Xiaoe
Published: March 2021

In this paper, a parameter‐optimal iterative learning control (POILC) scheme is developed for linear discrete‐time‐invariant systems with Markov parameters available. For the scheme the iteration‐time‐variable learning‐gain vector is assigned as the argument while the sequential performance index is consisting of the quadratic tracking error energy plus quadratic learning effort intensity weighed by the iteration‐varying tuning factor. By making use of matrix theory, the learning‐gain vector and the convergence rate are explicated which conveys that the POILC is a nonlinear scheme and is linearly monotonously convergent with the smaller tuning factors delivering the faster convergence. In particular, the linearly monotone convergences are respectively exploited for the extreme case when the tuning‐factor sequence is identically nullity and for the optimal performance index. Further, a quasi POILC is established which considers additive systematic parameters uncertainties in composing of the learning‐gain vector. Rigorous analysis indicates that the quasi POILC is linearly monotonically convergent within a wider uncertainty range which conveys that the POILC is robust to the system parameters uncertainties. Numerical simulations testify the validity and the effectiveness.
RETRACTED: Biochar and compost amendment impacts on soil water and pore size distribution of a loamy sand soil
Authors: Ibrahim Alaa , Horton Robert
Published: March 2021

Soil structure, which refers to aggregates and pore characteristics, reflects the spatial arrangement of soil particles and is a key component for crop yield and soil health. Well‐formed soil structure has favorable pore size distribution, which supports soil water flow and retention and healthy plant growth. Compost and biochar, important organic amendments, have a potential to influence soil structure, but their effects on specific soil types and soil properties have not been fully investigated. The main objective of this study was to investigate the impact of the additions of compost and/or date palm biochar on selected soil water indicators and pore size distribution of a loamy sand soil using disturbed soil samples. Statistical parameters of pore size distribution properties such as SD, kurtosis, skewness, modal diameter (dmode), median diameter (dmedian), and mean diameter (dmean) as well as plant available water capacity (PAWC), available soil water capacity (ASWC), saturated soil water content, and measured saturated hydraulic conductivity (Ksat) were measured and evaluated. The results showed that the dmode, dmedian, dmean, SD, skewness, and kurtosis values for untreated soil (control) were 31.6 μm, 25.8 μm, 23.5 μm, 3.3, −0.16, and 1.14, respectively. Biochar, compost, and a mixture of biochar–compost additions to a loamy sand soil significantly reduced dmode, dmedian, and dmean values in comparison with nonamended soil. Application of these amendments increased PAWC and ASWC and reduced Ksat of the loamy sand soil, significantly. Biochar–compost mixture has the most significant effect on improving soil water retention and PAWC.
System dynamics of cancer in erythropoiesis with multiple EPO feedbacks
Authors: Sajid Zamra , Andersen Morten , Ottesen Johnny T.
Published: March 2021

Blood production is a tightly regulated process, and disturbances can pose a severe risk to human health. Polycythemia vera (PV) is an example of such a disorder characterized by excessive production of erythrocytes and the presence of the JAK2V617F mutation. A 5D PV model with competing healthy and malignant cells, including erythropoietin (EPO), is proposed and analyzed. The production of EPO is governed by the number of erythrocytes, while EPO influences the proliferation and death rate of erythrocytes. Stem cell dynamics can be independently analyzed as a two‐dimensional system. A numerical analysis shows that steady states and their stability of the 2D stem cell PV submodel are in agreement with the PV model. Combining the model with data of PV patients, we demonstrate the model's prognostic significance. It follows that an efficient treatment must target stem cell properties such as the bone marrow microenvironment and stem cell death rates. © 2021 System Dynamics Society
Novel Therapeutic Platform of Micelles and Nanogels from Dopa‐Functionalized Triblock Copolymers
Authors: Zhang Yuning , Olofsson Kristina , Fan Yanmiao , Sánchez Carmen C. , Andrén Oliver C. J. , Qin Liguo , Fortuin Lisa , Jonsson Eva Malmström , Malkoch Michael
Published: March 2021

Multi‐drug delivery systems constructed from a basic polymeric scaffold, and which have the ability to target a variety of biomedical applications, can streamline the development of nanomedicine to provide both environmental and economical relief. Herein, amphiphilic ABA‐triblock copolymers are synthesized and assembled sequentially into micelles and nanogels as drug delivery systems following a thorough evaluation on advanced in vitro models to explore their potential for the treatment of cancer and bacterial infections. Short blocks of 5‐methyl‐5‐allyloxycarbonyl‐1,3‐dioxan‐2‐one (MAC) are oligomerized from PEG6k and thereafter functionalized with dihydroxyphenylalanine (dopa)‐functional thiols using thiol‐ene coupling (TEC) click chemistry. The copolymers self‐assemble into well‐defined micelles in aqueous solution and are further formulated into nanogels via UV‐induced TEC. The resulting spherical micelles and nanogels are stable nanoparticles, with sizes ranging between 100 and 200 nm. The nanogels are found to be non‐toxic to a panel of cell lines and mask the toxicity of the potent drugs until their release. The nanogels would be superior to micelles for the elimination of cancer cells supported by both 2D cell culture and a 3D spheroid model. The opposite conclusion could be drawn for bacteria inhibition.
An improved tensor regression model via location smoothing
Authors: Zhou Ya , He Kejun
Published: March 2021

Many applications of regression study the predictors with complex forms such as tensors. Besides low dimensional assumption, the effects of predictors with a tensor structure typically show clustered or smooth phenomena in the sense that adjacent elements have a similar effect on the response. To simultaneously incorporate the low‐rank and smoothness in tensor regression, we generalize the CANDECOMP/PARAFAC (CP) decomposition to a smooth version and propose a novel regression model based on the smoothed decomposition. The asymptotic theory of the proposed method is studied, which shows a faster rate of convergence than the one without incorporating the smoothness. The experiments on both synthetic and real data confirm that the proposed method has advantages over the alternative especially when the sample size is small.
Heyne, Roth, Roemer and Schultes, and the plant names published inNovae plantarum species praesertim Indiae orientalis
Authors: Turner I.M.
Published: March 2021

In 1814, A.W. Roth received a herbarium collection of some 1500 plants from Benjamin Heyne. Most of these specimens came from southern India where Heyne had worked as a doctor and naturalist since 1792. Roth wrote up the material in his bookNovae plantarum, which was published in 1821. However, he provided a manuscript copy to Roemer and Schultes, who were compiling an edition ofSystema vegetabilium. Many of Roth's new names based on the Heyne material first appeared in the first six volumes of theSystema. In this paper, 411 names published inNovae plantarumare listed with their correct citation and typification. The typification of Roth's names is complicated by the loss of a high proportion of his personal herbarium in Berlin in 1943. Notable points include:Jasminum montanumRoth is the correct name forJ. arborescensRoxb.,Panicum pilosissimumRoth is the correct name forP. rudgeiRoem. & Schult. andEuphorbia linearifoliaRoth does not need to be replaced byE. deccanensisV.S.Raju. Many names are typified.
The Coordination Polymer Cr(en)2As2VO7 Consisting of Alternating VO4 Tetrahedra and As2O5 Handles Decorated by Cr3+ Centered Complexes
Authors: Rasmussen Maren , Näther Christian , Bensch Wolfgang
Published: March 2021

The new coordination polymer Cr(en)2As2VO7 (en=ethylenediamine) was synthesized under solvothermal conditions as deep red crystals. In the crystal structure VO4 tetrahedra and As2O5 handles formed by corner‐sharing of two AsO3 pyramidal units are joined by common oxygen atoms into an undulated chain that is directed along the crystallographic b‐axis. The chain is decorated by [Cr(en)2]3+ complexes with the Cr3+ cation having bonds to two terminal O2− anions of the As2O5 moiety thus generating a CrN4O2 octahedron, which displays a cis‐configuration. The connection mode between Cr3+ and As2O5 leads to formation of a six‐membered CrAs2O3 ring. The chains are arranged in a layer‐like fashion in the (001) plane and these layers are stacked along [001]. A large number of N−H⋅⋅⋅O and C−H⋅⋅⋅O hydrogen bonds generate a three dimensional network. A Hirshfeld surface analysis was performed for visualizing the extended interchain interactions. The hydrogen bonding interactions are clearly detected in the IR spectrum. The UV‐Vis spectrum shows an absorption at 2.3 eV which is in agreement with the red color of the sample.
The past, present and future of hormonal contraceptive use in managed captive female tiger populations with a focus on the current use of deslorelin acetate
Authors: Guthrie Amanda , Strike Taina , Patterson Stuart , Walker Corinne , Cowl Veronica , Franklin Ashley D. , Powell David M.
Published: March 2021

Tigers (Panthera tigris spp.) are endangered in the wild; ensuring sustainable insurance populations requires careful planning within zoological collections. In captive situations, contraceptives are often used to control breeding and ensure genetically viable populations that contain manageable numbers of animals; reversible contraceptives are ideal because they offer flexibility for breeding management. Historically, synthetic progestins, such as melengestrol acetate implants, were used in female tigers, but these are associated with an increased risk of reproductive pathology and subsequent infertility. Recent management advice to ex‐situ collections has been to transition to the use of gonadotropin‐releasing hormone agonists, such as deslorelin acetate implants, which do not appear to have a similar risk of reproductive pathology but are associated with highly variable reversal times in exotic felids. Using data from 917 contraceptive records in female tigers captured by the Association of Zoos and Aquariums Reproductive Management Center and the European Association of Zoos and Aquaria Reproductive Management Group's joint Contraception Database and from supplementary surveys, this study reviews the changing use of contraceptives in captive female tigers. The aim was to describe the historical and current use of contraceptives and provide a comprehensive assessment on the use of deslorelin implants, including data on product protocols, efficacy, pathology, and reversibility. This study determined that current dose, frequency, reversibility, and anatomical placement sites of deslorelin implants are highly variable, indicating that specific, readily available, unified, evidence‐based recommendations on the use of deslorelin would be useful for future contraceptive use in managed tiger populations.
Black hole perturbations of massive and partially massless spin-2 fields in (anti) de Sitter spacetime
Authors: Rosen Rachel A. , Santoni Luca
Published: March 2021

Abstract

We provide a systematic and comprehensive derivation of the linearized dynamics of massive and partially massless spin-2 particles in a Schwarzschild (anti) de Sitter black hole background, in four and higher spacetime dimensions. In particular, we show how to obtain the quadratic actions for the propagating modes and recast the resulting equations of motion in a Schrödinger-like form. In the case of partially massless fields in Schwarzschild de Sitter spacetime, we study the isospectrality between modes of different parity. In particular, we prove isospectrality analytically for modes with multipole number L = 1 in four spacetime dimensions, providing the explicit form of the underlying symmetry. We show that isospectrality between partially massless modes of different parity is broken in higher-dimensional Schwarzschild de Sitter spacetimes.
Elliptic modular graph forms. Part I. Identities and generating series
Authors: D’Hoker Eric , Kleinschmidt Axel , Schlotterer Oliver
Published: March 2021

Abstract

Elliptic modular graph functions and forms (eMGFs) are defined for arbitrary graphs as natural generalizations of modular graph functions and forms obtained by including the character of an Abelian group in their Kronecker-Eisenstein series. The simplest examples of eMGFs are given by the Green function for a massless scalar field on the torus and the Zagier single-valued elliptic polylogarithms. More complicated eMGFs are produced by the non-separating degeneration of a higher genus surface to a genus one surface with punctures. eMGFs may equivalently be represented by multiple integrals over the torus of combinations of coefficients of the Kronecker-Eisenstein series, and may be assembled into generating series. These relations are exploited to derive holomorphic subgraph reduction formulas, as well as algebraic and differential identities between eMGFs and their generating series.
On the three-particle analog of the Lellouch-Lüscher formula
Authors: Müller Fabian , Rusetsky Akaki
Published: March 2021

Abstract

Using non-relativistic effective field theory, we derive a three-particle analog of the Lellouch-Lüscher formula at the leading order. This formula relates the three-particle decay amplitudes in a finite volume with their infinite-volume counterparts and, hence, can be used to study the three-particle decays on the lattice. The generalization of the approach to higher orders is briefly discussed.
A step in the Delaunay mosaic of order k
Authors: Edelsbrunner Herbert , Nikitenko Anton , Osang Georg
Published: March 2021

Given a locally finite set $$X \subseteq {{\mathbb {R}}}^d$$

X
⊆

R

d

and an integer $$k \ge 0$$

k
≥
0

, we consider the function $${\mathbf{w}_{k}^{}} :{\mathrm{Del}_{k}{({X})}} \rightarrow {{\mathbb {R}}}$$

w

k

:

Del
k

(
X
)

→
R

on the dual of the order-k Voronoi tessellation, whose sublevel sets generalize the notion of alpha shapes from order-1 to order-k (Edelsbrunner et al. in IEEE Trans Inf Theory IT-29:551–559, 1983; Krasnoshchekov and Polishchuk in Inf Process Lett 114:76–83, 2014). While this function is not necessarily generalized discrete Morse, in the sense of Forman (Adv Math 134:90–145, 1998) and Freij (Discrete Math 309:3821–3829, 2009), we prove that it satisfies similar properties so that its increments can be meaningfully classified into critical and non-critical steps. This result extends to the case of weighted points and sheds light on k-fold covers with balls in Euclidean space.
Chemoradiotherapy by intensity-modulated radiation therapy with simultaneous integrated boost in locally advanced or oligometastatic non-small-cell lung cancer—a two center experience
Authors: Mantel Frederick , Müller Elena , Kleine Philip , Zimmermann Marcus , Exner Florian , Richter Anne , Weick Stefan , Ströhle Serge , Polat Bülent , Höcht Stefan , Flentje Michael
Published: March 2021

Purpose

Integrating moderate hypofractionation to the macroscopic tumor with elective nodal irradiation while sparing the organs at risk (OAR) in chemoradiotherapy of locally advanced non-small-cell lung cancer.

Methods

From 2010–2018, treatment, patient and tumor characteristics of 138 patients from two radiation therapy centers were assessed. Chemoradiotherapy by intensity-modulated radiation therapy (IMRT) with a simultaneous integrated boost (SIB) to the primary tumor and macroscopic lymph node metastases was used.

Results

A total of 124 (90%) patients received concurrent chemotherapy. 106 (76%) patients had UICC (Union for International Cancer Control) stage ≥IIIB and 21 (15%) patients had an oligometastatic disease (UICC stage IV). Median SIB and elective total dose was 61.6 and 50.4 Gy in 28 fractions, respectively. Furthermore, 64 patients (46%) had an additional sequential boost to the primary tumor after the SIB-IMRT main series: median 6.6 Gy in median 3 fractions. The median cumulative mean lung dose was 15.6 Gy (range 6.2–29.5 Gy). Median follow-up and radiological follow-up for all patients was 18.0 months (range 0.6–86.9) and 16.0 months (range 0.2–86.9), respectively. Actuarial local control rates at 1, 2 and 3 years were 80.4, 68.4 and 57.8%. Median overall survival and progression-free survival was 30.0 months (95% confidence interval [CI] 23.5–36.4) and 12.1 months (95% CI 8.2–16.0), respectively. Treatment-related toxicity was moderate. Radiation-induced pneumonitis grade 2 and grade 3 occurred in 13 (9.8%) and 3 (2.3%) patients.

Conclusions

Chemoradiotherapy using SIB-IMRT showed promising local tumor control rates and acceptable toxicity in patients with locally advanced and in part oligometastatic lung cancer. The SIB concept, resulting in a relatively low mean lung dose, was associated with low numbers of clinically relevant pneumonitis. The overall survival appears promising in the presence of a majority of patients with UICC stage ≥IIIB disease.
The Himalayan Onion (Allium wallichii Kunth) Harbors Unique Spatially Organized Bacterial Communities
Authors: Chen Xiaoyulong , Krug Lisa , Yang Maofa , Berg Gabriele , Cernava Tomislav
Published: March 2021

Plant-associated microorganisms are known to contribute with various beneficial functions to the health and productivity of their hosts, yet the microbiome of most plants remains unexplored. This especially applies to wild relatives of cultivated plants, which might harbor beneficial microorganisms that were lost during intensive breeding. We studied bacterial communities of the Himalayan onion (Allium wallichii Kunth), a wild relative of onion native to mountains in East Asia. The bacterial community structure was assessed in different plant microhabitats (rhizosphere, endosphere, anthosphere) by sequencing of 16S rRNA gene fragment amplicons. Targeted bioinformatic analyses were implemented in order to identify unique features in each habitat and to map the overall community in the first representative of the Amaryllidaceae plant family. The highest bacterial diversity was found for bulk soil (Shannon index, H′ 9.3) at the high-altitude sampling location. It was followed by the plant rhizosphere (H′ 8.9) while communities colonizing flowers (H′ 6.1) and the endosphere (H′ 6.5 and 5.6) where less diverse. Interestingly, we observed a non-significant rhizosphere effect. Another specificity of the microbiome was its high evenness in taxonomic distribution, which was so far not observed in plant microbiomes. Pseudomonas was identified among additional 10 bacterial genera as a plant-specific signature. The first insights into the microbiome of a plant in the widespread Allium genus will facilitate upcoming comparisons with its domesticated relatives while additionally providing a detailed microbiome mapping of the plant’s microhabitats to facilitate bioresource mining.
Genetic barcodes allow traceability of CRISPR/Cas9-derived Aspergillus niger strains without affecting their fitness
Authors: Garrigues Sandra , Kun Roland S. , de Vries Ronald P.
Published: March 2021

Safe use of genetically modified organisms (GMOs) in biotechnology requires the ability to track the presence of these strains in any environment in which they are applied. For this, introduction of genetic barcodes within the editing site represents a valuable tool for the identification of microbial strains that have undergone genetic modifications. However, it is not known whether these barcodes would have any unexpected effect in the resulting strains or affect the efficiency of the genetic modification. CRISPR/Cas9 has become one of the fastest-growing technologies for genome editing in a range of organisms, including fungi. However, this technology enables the generation of scarless GMOs that are very difficult to distinguish from naturally occurring mutants or other modified organisms. In this study, we address this issue using the industrial workhorse Aspergillus niger as a test case. We applied CRISPR/Cas9 technology to delete the genes encoding the transcriptional regulators XlnR and AraR, involved in the production of plant biomass-degrading enzymes. We generated 20-bp barcoded and non-barcoded ΔxlnR and ΔaraR mutants and analyzed the traceability and fitness of the resulting strains, as well as the efficiency of the genetic modification. Results showed that both barcoded and non-barcoded mutants can be traced by routine PCR reactions when the specific CRISPR/Cas9 modification is known. Additionally, barcodes neither affected the efficiency of the genetic modification nor the growth or protein production of the resulting strains. These results confirm the suitability of genetic barcodes to trace CRISPR-derived GMOs without affecting the performance of the resulting strains.
Quantification of dual-energy CT-derived functional parameters as potential imaging markers for progression of idiopathic pulmonary fibrosis
Authors: Scharm Sarah C. , Vogel-Claussen Jens , Schaefer-Prokop Cornelia , Dettmer Sabine , Knudsen Lars , Jonigk Danny , Fuge Jan , Apel Rosa-Marie , Welte Tobias , Wacker Frank , Prasse Antje , Shin Hoen-oh
Published: March 2021

Objectives

The individual course of disease in idiopathic pulmonary fibrosis (IPF) is highly variable. Assessment of disease activity and prospective estimation of disease progression might have the potential to improve therapy management and indicate the onset of treatment at an earlier stage. The aim of this study was to evaluate whether regional ventilation, lung perfusion, and late enhancement can serve as early imaging markers for disease progression in patients with IPF.

Methods

In this retrospective study, contrast-enhanced dual-energy CT scans of 32 patients in inspiration and delayed expiration were performed at two time points with a mean interval of 15.4 months. The pulmonary blood volume (PBV) images obtained in the arterial and delayed perfusion phase served as a surrogate for arterial lung perfusion and parenchymal late enhancement. The virtual non-contrast (VNC) images in inspiration and expiration were non-linearly registered to provide regional ventilation images. Image-derived parameters were correlated with longitudinal changes of lung function (FVC%, DLCO%), mean lung density in CT, and CT-derived lung volume.

Results

Regional ventilation and late enhancement at baseline preceded future change in lung volume (R - 0.474, p 0.006/R - 0.422, p 0.016, respectively) and mean lung density (R - 0.469, p 0.007/R - 0.402, p 0.022, respectively). Regional ventilation also correlated with a future change in FVC% (R - 0.398, p 0.024).

Conclusion

CT-derived functional parameters of regional ventilation and parenchymal late enhancement are potential early imaging markers for idiopathic pulmonary fibrosis progression.

Key Points

• Functional CT parameters at baseline (regional ventilation and late enhancement) correlate with future structural changes of the lung as measured with loss of lung volume and increase in lung density in serial CT scans of patients with idiopathic pulmonary fibrosis.

• Functional CT parameter measurements in high-attenuation areas (- 600 to - 250 HU) are significantly different from normal-attenuation areas (- 950 to - 600 HU) of the lung.

• Mean regional ventilation in functional CT correlates with a future change in forced vital capacity (FVC) in pulmonary function tests.
Besnoitiosis in donkeys: an emerging parasitic disease of equids in Italy
Authors: Villa Luca , Gazzonis Alessia Libera , Diezma-Diaz Carlos , Perlotti Chiara , Zanzani Sergio Aurelio , Ferrucci Francesco , Álvarez-García Gema , Manfredi Maria Teresa
Published: March 2021

Besnoitiosis is an emerging parasitic disease of equids. Italy is one of the few European countries where the circulation of Besnoitia spp. antibodies was demonstrated. In this study, a case of clinical besnoitiosis in two donkeys in northern Italy is reported. The two animals were clinically examined. Serum and blood samples were analyzed for the detection of Besnoitia spp. antibodies and for hematology, biochemistry, and enzyme activity, respectively. ITS-1 PCR and sequencing were carried out on DNA extracted from skin biopsies. Clinical examination revealed numerous scleral pearls in eyes of both animals; alopecia and hyperkeratosis with skin nodules in the region of the neck, hind leg, and on the pinnae were detected. No cysts were evidenced by endoscopy in respiratory and genital tracts. Both animals resulted seropositive to Besnoitia spp. antibodies by Western Blot. Hematology evidenced light anemia, leukocytosis with eosinophilia, and lymphocytosis; biochemistry and enzyme activity revealed hypoalbuminemia with decreased albumin/globulin ratio and elevated alkaline phosphatase values. Parasitic DNA extracted from skin biopsies of both donkeys demonstrated a homology of 100% with Besnoitia spp. This first clinical case of besnoitiosis in two donkeys in Italy both confirms the circulation of Besnoitia spp. in Italian equids and demonstrates that the distribution area of equine besnoitiosis in Europe could be wider than expected. Further studies are needed to infer its relevance, in relation to seroprevalence and clinical disease, and to identify the species of Besnoitia infecting donkeys. Besnoitiosis may be a neglected disease of donkeys in Europe: an early and accurate diagnosis is fundamental to implement adequate control measures to prevent a “silent” spread of Besnoitia spp. infection in equids populations.
Deep learning-based high-throughput phenotyping can drive future discoveries in plant reproductive biology
Authors: Warman Cedar , Fowler John E.
Published: March 2021

Key message

Advances in deep learning are providing a powerful set of image analysis tools that are readily accessible for high-throughput phenotyping applications in plant reproductive biology.

High-throughput phenotyping systems are becoming critical for answering biological questions on a large scale. These systems have historically relied on traditional computer vision techniques. However, neural networks and specifically deep learning are rapidly becoming more powerful and easier to implement. Here, we examine how deep learning can drive phenotyping systems and be used to answer fundamental questions in reproductive biology. We describe previous applications of deep learning in the plant sciences, provide general recommendations for applying these methods to the study of plant reproduction, and present a case study in maize ear phenotyping. Finally, we highlight several examples where deep learning has enabled research that was previously out of reach and discuss the future outlook of these methods.
Mechanics of tubular helical assemblies: ensemble response to axial compression and extension
Authors: Quaglierini Jacopo , Lucantonio Alessandro , DeSimone Antonio
Published: March 2021

Nature and technology often adopt structures that can be described as tubular helical assemblies. However, the role and mechanisms of these structures remain elusive. In this paper, we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchhoff rods, arranged in pairs with opposite chirality and connected by pin joints, both analytically and numerically. We first focus on compression and find that, whereas a single helical rod would buckle, the rods of the assembly deform coherently as stable helical shapes wound around a common axis. Moreover, we investigate the response of the assembly under different boundary conditions, highlighting the emergence of a central region where rods remain circular helices. Secondly, we study the effects of different hypotheses on the elastic properties of rods, i.e., stress-free rods when straight versus when circular helices, Kirchhoff’s rod model versus Sadowsky’s ribbon model. Summing up, our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods, as well as some interesting features, and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.

Graphic Abstract

We study the mechanical response under compression/extension of an assembly composed of 8 helical rods, pin-jointed and arranged in pairs with opposite chirality. In compression we find that, whereas a single rod buckles (a), the rods of the assembly deform as stable helical shapes (b). We investigate the effect of different boundary conditions and elastic properties on the mechanical response, and find that the deformed geometries exhibit a common central region where rods remain circular helices. Our findings highlight the key role of mutual interactions in the ensemble response and shed some light on the reasons why tubular helical assemblies are so common and persistent.
The Polito Surface Wave flat-file Database (PSWD): statistical properties of test results and some inter-method comparisons
Authors: Passeri Federico , Comina Cesare , Foti Sebastiano , Socco Laura Valentina
Published: March 2021

The compilation and maintenance of experimental databases are of crucial importance in all research fields, allowing for researchers to develop and test new methodologies. In this work, we present a flat-file database of experimental dispersion curves and shear wave velocity profiles, mainly from active surface wave testing, but including also data from passive surface wave testing and invasive methods. The Polito Surface Wave flat-file Database (PSWD) is a gathering of experimental measurements collected within the past 25 years at different Italian sites. Discussion on the database content is reported in this paper to evaluate some statistical properties of surface wave test results. Comparisons with other methods for shear wave velocity measurements are also considered. The main novelty of this work is the homogeneity of the PSWD in terms of processing and interpretation methods. A common processing strategy and a new inversion approach were applied to all the data in the PSWD to guarantee consistency. The PSWD can be useful for further correlation studies and is made available as a reference benchmark for the validation and verification of novel interpretation procedures by other researchers.
Ethnic Identity and Genome Wide Runs of Homozygosity
Authors: Fieder Martin , Mitchell Brittany L. , Gordon Scott , Huber Susanne , Martin Nicholas G.
Published: March 2021

It is long known that inbreeding increases the detrimental effects of recessive sequence variants in “Runs of Homozygosity” (ROHs). However, although the phenotypic association of ROH has been investigated for a variety of traits, the statistical power of the results often remains limited as a sufficiently high number of cases are available for only a restricted number of traits. In the present study, we aim to analyze the association of runs of homozygosity with the trait “in-group ethnic favoritism”. This analysis assumes that if ethnic identity is important for an individual, that individual may tend to marry more frequently within their own group and therefore ROH are expected to increase. We hypothesize that an attitude preferring one’s own ethnic group may be associated with a stronger tendency of inbreeding and, as a result, with more and longer ROHs. Accordingly, we investigated the association between the attitude to someone’s own ethnicity and ROH, using the Wisconsin Longitudinal data (WLS, total N ~ 9000) as discovery data set and the Brisbane Twin data as replication data set (N ~ 8000). We find that both the number as well as the total length of homozygous segments are significantly positively associated with “in-group ethnic favoritism”, independent of the method used for ROH calculation.
On the necessity of explicit cross-layer data formats in near-data processing systems
Authors: Weber Lukas , Vinçon Tobias , Knödler Christian , Solis-Vasquez Leonardo , Bernhardt Arthur , Petrov Ilia , Koch Andreas
Published: March 2021

Massive data transfers in modern data-intensive systems resulting from low data-locality and data-to-code system design hurt their performance and scalability. Near-Data processing (NDP) and a shift to code-to-data designs may represent a viable solution as packaging combinations of storage and compute elements on the same device has become feasible. The shift towards NDP system architectures calls for revision of established principles. Abstractions such as data formats and layouts typically spread multiple layers in traditional DBMS, the way they are processed is encapsulated within these layers of abstraction. The NDP-style processing requires an explicit definition of cross-layer data formats and accessors to ensure in-situ executions optimally utilizing the properties of the underlying NDP storage and compute elements. In this paper, we make the case for such data format definitions and investigate the performance benefits under RocksDB and the COSMOS hardware platform.
Review of petroleum toxicity in marine reptiles
Authors: Ruberg Elizabeth J. , Williams Tony D. , Elliott John E.
Published: March 2021

Worldwide petroleum exploration and transportation continue to impact the health of the marine environment through both catastrophic and chronic spillage. Of the impacted fauna, marine reptiles are often overlooked. While marine reptiles are sensitive to xenobiotics, there is a paucity of petroleum toxicity data for these specialized fauna in peer reviewed literature. Here we review the known impacts of petroleum spillage to marine reptiles, specifically to marine turtles and iguanas with an emphasis on physiology and fitness related toxicological effects. Secondly, we recommend standardized toxicity testing on surrogate species to elucidate the mechanisms by which petroleum related mortalities occur in the field following catastrophic spillage and to better link physiological and fitness related endpoints. Finally, we propose that marine reptiles could serve as sentinel species for marine ecosystem monitoring in the case of petroleum spillage. Comprehensive petroleum toxicity data on marine reptiles is needed in order to serve as a foundation for future research with newer, unconventional crude oils of unknown toxicity such as diluted bitumen.
The nature of build changes
Authors: Macho Christian , Beyer Stefanie , McIntosh Shane , Pinzger Martin
Published: March 2021

Build systems are an essential part of modern software projects. As software projects change continuously, it is crucial to understand how the build system changes because neglecting its maintenance can, at best, lead to expensive build breakage, or at worst, introduce user-reported defects due to incorrectly compiled, linked, packaged, or deployed official releases. Recent studies have investigated the (co-)evolution of build configurations and reasons for build breakage; however, the prior analysis focused on a coarse-grained outcome (i.e., either build changing or not). In this paper, we present BuildDiff, an approach to extract detailed build changes from Maven build files and classify them into 143 change types. In a manual evaluation of 400 build-changing commits, we show that BuildDiff can extract and classify build changes with average precision, recall, and f1-scores of 0.97, 0.98, and 0.97, respectively. We then present two studies using the build changes extracted from 144 open source Java projects to study the frequency and time of build changes. The results show that the top-10 most frequent change types account for 51% of the build changes. Among them, changes to version numbers and changes to dependencies of the projects occur most frequently. We also observe frequently co-occurring changes, such as changes to the source code management definitions, and corresponding changes to the dependency management system and the dependency declaration. Furthermore, our results show that build changes frequently occur around release days. In particular, critical changes, such as updates to plugin configuration parts and dependency insertions, are performed before a release day. The contributions of this paper lay in the foundation for future research, such as for analyzing the (co-)evolution of build files with other artifacts, improving effort estimation approaches by incorporating necessary modifications to the build system specification, or automatic repair approaches for configuration code. Furthermore, our detailed change information enables improvements of refactoring approaches for build configurations and improvements of prediction models to identify error-prone build files.
Natural Deduction Bottom Up
Authors: Zimmermann Ernst
Published: March 2021

The paper introduces a new type of rules into Natural Deduction, elimination rules by composition. Elimination rules by composition replace usual elimination rules in the style of disjunction elimination and give a more direct treatment of additive disjunction, multiplicative conjunction, existence quantifier and possibility modality. Elimination rules by composition have an enormous impact on proof-structures of deductions: they do not produce segments, deduction trees remain binary branching, there is no vacuous discharge, there is only few need of permutations. This new type of rules fits especially to substructural issues, so it is shown for Lambek Calculus, i.e. intuitionistic non-commutative linear logic and to its extensions by structural rules like permutation, weakening and contraction. Natural deduction formulated with elimination rules by composition from a complexity perspective is superior to other calculi.
A New Application-Aware No-Reference Quality Assessment Method for IP Voice Services
Authors: Orosz Péter , Tóthfalusi Tamás
Published: March 2021

The increasing number of Voice over LTE deployments and IP-based voice services raise the demand for their user-centric service quality monitoring. This domain’s leading challenge is measuring user experience quality reliably without performing subjective assessments or applying the standard full-reference objective models. While the former is time- and resource-consuming and primarily executed ad-hoc, the latter depends upon a reference source and processes the voice payload that may offend user privacy. This paper presents a packet-level measurement method (introducing a novel metric set) to objectively assess network and service quality online. It is accomplished without inspecting the voice payload and needing the reference voice sample. The proposal has three contributions: (i) our method focuses on the timeliness of the media traffic. It introduces new performance metrics that describe and measure the service’s time-domain behavior from the voice application viewpoint. (ii) Based on the proposed metrics, we also present a no-reference Quality of Experience (QoE) estimation model. (iii) Additionally, we propose a new method to identify the pace of the speech (slow or dynamic) as long as voice activity detection (VAD) is present between the endpoints. This identification supports the introduced quality model to estimate the perceived quality with higher accuracy. The performance of the proposed model is validated against a full-reference voice quality estimation model called AQuA, using real VoIP traffic (originated in assorted voice samples) in controlled transmission scenarios.
Commons and the nature of modernity: towards a cosmopolitical view on craft guilds
Authors: De Munck Bert
Published: March 2021

This paper argues that historical research on late medieval and early modern craft guilds fails to escape teleological and anachronistic views, including when they are addressed as commons or ‘institutions for collective action’. These present-day conceptual lenses do not only create idealized views on guilds, but also of the contexts in which they operated, especially the state and the market. This is especially the case with neo-institutional views on the commons, which fall back on a transhistorical rational actor, who can choose between three options for the allocation of resources and surpluses, namely the state, the market and the common. The paper shows that guilds were fundamentally entangled with both the state and the market and that their ethic implied a less utilitarian and instrumental attitude towards natural resources. The consequence of this is that the history of the guilds offers different lessons to present-day commoners than those implied by present-day research. With an eye at launching a reflection on that, I argue in favour of a cosmopolitical perspective, which invites to take fundamentally different worldviews seriously. This includes questioning our own conceptual and analytical abstractions like the state, the market and the individual, up to and including the very distinction between nature and society or nature and politics, which are at the very basis of modern science itself.
Zielorientierung, Burnout und Engagement im Hochschulkontext: Integration von Zielorientierung in das Study Demands-Resources-Modell
Authors: Niewöhner Thomas , Hoerdler Leonie , Roxel Alina , Meindl Merle , Teuber Ziwen
Published: March 2021

Hintergrund

Personale Ressourcen in Form motivationaler Faktoren haben in der bisherigen Forschung zum Thema Burnout im Hochschulkontext wenig Beachtung gefunden. Das Ziel der vorliegenden Studie war es, Annäherungslern- und -leistungsziele als personale Ressource in das etablierte Study Demands-Resources-Modell (SD-R-Modell) zu integrieren und ihren Zusammenhang mit Burnout sowie Engagement im Studium zu untersuchen.

Methodik

Mithilfe eines quantitativen Online-Fragebogens wurden Querschnittsdaten von 347 Studierenden (MAlter = 22,9, SD = 3,2 Jahre) verschiedener deutscher Hochschulen erhoben und mittels latenter Strukturgleichungsmodelle untersucht.

Ergebnisse

Die Ergebnisse zeigen, dass sich das SD-R-Modell replizieren lässt. Annäherungslernziele vermitteln den Zusammenhang zwischen Ressourcen und Engagement positiv. Entgegen der Hypothese vermitteln Annäherungslernziele den Zusammenhang zwischen Ressourcen und Burnout positiv. Leistungszielorientierung ist kein signifikanter Mediator.

Diskussion

Die Ergebnisse unterstreichen die Relevanz von Annäherungslernzielen für das Engagement und die psychische Gesundheit Studierender.
Teaching and learning robotic surgery at the dual console: a video-based qualitative analysis
Authors: Cristofari Hélène , Jung Minoa Karin , Niclauss Nadja , Toso Christian , Kloetzer Laure
Published: March 2021

Robotic-assisted surgery (RAS) involves training processes and challenges that differ from open or laparoscopic surgery, particularly regarding the possibilities of observation and embodied guidance. The video recording and the dual-console system creates a potential opportunity for participation. Our research, conducted within the department of visceral surgery of a big Swiss, public, academic hospital, uses a methodology based on the co-analysis of video recordings with surgeons in self-confrontation interviews, to investigate the teaching activity of the lead surgeon supervising a surgeon in training at the dual console. Three short sequences have been selected for the paper. Our analysis highlights the skills-in-construction of the surgeon in training regarding communication with the operating team, fluency of working with three hands, and awareness of the whole operating site. It also shows the divergent necessities of enabling verbalization for professional training, while ensuring a quiet and efficient environment for medical performance. To balance these requirements, we argue that dedicated briefing and debriefing sessions may be particularly effective; we also suggest that the self-confrontation video technique may be valuable to support the verbalization on both the mentor’s and the trainee’s side during such debriefing, and to enhance the mentor’s reflexivity regarding didactic choices.
RADIP-JF – Radikalisierung Interventionsprogramm in der Jugendforensik
Authors: Vertone Leonardo
Published: March 2021

Der Beitrag stellt mit dem RADIP ein psychotherapeutisches Interventionsprogramm vor, das zum Ziel hat, das Fortschreiten von Radikalisierungsprozessen bei Jugendlichen zu verhindern (Deradikalisierung) und die Wahrscheinlichkeit einer Ausübung extremistischer Taten zu verringern (Distanzierung). Das Programm ist deliktpräventiv konzipiert und vereint forensische und kognitiv-verhaltenstherapeutische Methodiken. Es ist strukturiert und multimodal und kann im Einzel- oder im Gruppensetting durchgeführt werden. Nebst der Auseinandersetzung der Teilnehmenden mit Themen, die mit (ihrer) problematischen Radikalisierung in Verbindung stehen, beinhalten die Module Wissens- und Kompetenzzuwachs, Reflexion der eigenen Identität, Bewusstsein und Stärkung eigener prosozialer Ziele sowie Erhöhung der Entscheidungs- und Steuerungsfähigkeit (ressourcenorientierter Zugang). Bestandteil des Programms ist eine Abklärungsphase, welche eine psychiatrisch-psychopathologische und (entwicklungs-)psychologische Diagnostik sowie ein forensisches „risk assessment“ beinhaltet. Das daraus resultierende Fallverständnis erlaubt es, individuelle Schwerpunkte zu setzen und flexibel zu intervenieren. Das Programm ist in einen multisystemischen und -disziplinären Rahmen eingebettet, d. h., Eltern oder sonstige nahe Bezugs- sowie Hilfspersonen werden miteinbezogen.
Overall and diagnosis-specific sickness absence and disability pension in colorectal cancer survivors and references in Sweden
Authors: Beermann Luisa Christine , Alexanderson Kristina , Martling Anna , Chen Lingjing
Published: March 2021

Purpose

To longitudinally investigate overall and diagnosis-specific sickness absence (SA) and disability pension (DP) in colorectal cancer (CRC) survivors and references and to identify potential risk factors.

Methods

This longitudinal register-based cohort study included all patients living in Sweden, diagnosed with a first primary CRC in 2008–2011 when aged 18–62 (n=6679), and their matched references (n=26 716). Net days of SA (in SA spells >14 days) and DP were analyzed from 2 years before through 5 years after diagnosis, overall and by specific diagnoses. Among survivors, risk factors for future SADP were explored using logistic regression.

Results

In survivors, SA peaked in year 1 postdiagnosis, with 62.5% having at least some SA, and then gradually decreased to 20.1% in year 5. In the 2 years after diagnosis, CRC was the most common SA diagnosis in survivors, while SA due to mental diagnoses remained similar to the references. Notable risk factors for postdiagnostic SA or DP were rectal cancer diagnosis, advanced cancer stage at diagnosis, lower educational level, born outside of Sweden, and pre-diagnostic SA, mental morbidity, and comorbidities.

Conclusion

During 5 years after a CRC diagnosis, CRC survivors had higher levels of postdiagnostic SA and DP than the references, which was mostly due to CRC diagnoses. Although their SA lowered gradually, it did not return to pre-diagnostic levels.

Implications for Cancer Survivors

Our results provide valuable information for patients with CRC diagnosis, especially that most have none or low levels of SA/DP after a few years.