bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA‐Directed Assembly of a Cell‐Responsive Biohybrid Interface for Cargo Release
Authors: Sun Pengchao , Scharnweber Tim , Wadhwani Parvesh , Rabe Kersten S. , Niemeyer Christof M.
Published: May 2021

The development of a DNA‐based cell‐responsive biohybrid interface that can be used for spatially confined release of molecular cargo is reported. To this end, tailored DNA–protein conjugates are designed as gatekeepers that can be specifically cleaved by matrix metalloproteases (MMPs), which are secreted by many cancer cells. These gatekeepers can be installed by DNA hybridization on the surface of mesoporous silica nanoparticles (MSNs). The MSNs display another orthogonal DNA oligonucleotide that can be exploited for site‐selective immobilization on solid glass surfaces to yield micropatterned substrates for cell adhesion. Using the human fibrosarcoma cell line HT1080 that secretes MMPs, it is demonstrated that the biohybrid surface is specifically modified by the cells to release both MSN‐bound gatekeeper proteins and the encapsulated cargo peptide KLA. In view of the enormously high modularity of the system presented here, this approach promising for applications in drug delivery, tissue engineering, or other areas of nanobiotechnology is considered.
High‐Voltage and Super‐Stable Aqueous Sodium–Zinc Hybrid Ion Batteries Enabled by Double Solvation Structures in Concentrated Electrolyte
Authors: Ao Huaisheng , Zhu Weiduo , Liu Mengke , Zhang Wanqun , Hou Zhiguo , Wu Xiaojun , Zhu Yongchun , Qian Yitai
Published: May 2021

Aqueous sodium–zinc hybrid ion batteries are attracting extensive attention due to high energy density, low cost, and environmental friendliness. Unfortunately, there are still some drawbacks associated with the low voltage and cycle performance degradation that limit their practical application. Here, a concentrated aqueous electrolyte with solvation‐modulated Zn2+ is reported that reduces the hydrogen evolution reaction on the surface of Zn metal, avoiding the generation of ZnO and uneven deposition. Accordingly, the Zn anode exhibits 1600 h Zn plating/stripping and ≈99.96% Coulombic efficiency after 700 cycles. In addition, solvation‐modulated Na+ promotes the excellent structural stability of zinc hexacyanoferrate (ZnHCF) due to the rhombohedral–rhombohedral rather than rhombohedral–cubic phase transition. A ZnHCF//Zn full cell delivers an average voltage of 1.76 V and 98% capacity retention after 2000 cycles at 5 C rates.
New Mold Slag Compositions for the Continuous Casting of Soft Steels
Authors: Kölbl Nathalie
Published: May 2021

Several fluorine‐free mold slag compositions have already been established in the literature. In all cases, the formation of a crystalline phase exhibiting behavior similar to that of cuspidine is emphasized to control horizontal heat transfer without influencing the lubrication performance for the casting of peritectic steel grades. In contrast, for casting soft steels, glassy solidification of the slag is required. Herein, different slag compositions involving the selected oxides are developed with the help of FactSage calculations. Mixtures of pure raw materials are melted at 1673 K and quenched to 295 K. It is observed that B2O3 increases the glass‐forming ability of the slags. To obtain the glassy phase, the composition must satisfy the conditions and . For TiO2 content <10 wt%, glassy solidification is detected after quenching to room temperature. However, this phenomenon‐is not observed for slags with TiO2 content >15 wt%. Moreover, the addition of alumina and alkali oxides enhances crystallization. Based on these findings, promising mold slag compositions are designed and characterized in the laboratory using a furnace crystallization test, mineralogical investigations, and the single/double hot thermocouple technique. From the investigated mixtures, three compositions are suggested for use in continuous casting processes.
In Vitro Effects of Stachyose on the Human Gut Microbiota
Authors: Zhao Zhonglin , Liu Wei , Pi Xionge
Published: May 2021

Gut microbiota plays an important role in human health. Stachyose, an oligosaccharide, modulates the gut microbiota composition in animals. However, the role of stachyose in promoting the proliferation of probiotics and whether it inhibits pathogenic micro‐organisms in human gut microbiota has not been explored. Therefore, in this study, the effects of stachyose on the gut microbiota and its metabolites in humans are explored. Three concentrations of stachyose are used as the sole carbon source for in vitro fermentation. Results show that stachyose improves beta diversity and increases the concentration of short‐chain fatty acid (SCFAs), mainly acetic acid and butyric acid. Stachyose is found to promote the relative abundance of Bifidobacteria, Faecalibacterium, Lactobacillus, and Prevotella genera in the gut microbiota. Besides, stachyose significantly reduces the relative abundance of Bacteroides and Escherichia‐Shigella genera. The findings show that stachyose increases beneficial microbiota, therefore, it is a useful prebiotic which modulates the composition of the gut microbiota.
Directed differentiation and direct reprogramming: Applying stem cell technologies to hearing research
Authors: Roccio Marta
Published: May 2021

Hearing loss is the most widely spread sensory disorder in our society. In the majority of cases, it is caused by the loss or malfunctioning of cells in the cochlea: the mechanosensory hair cells, which act as primary sound receptors, and the connecting auditory neurons of the spiral ganglion, which relay the signal to upper brain centers. In contrast to other vertebrates, where damage to the hearing organ can be repaired through the activity of resident cells, acting as tissue progenitors, in mammals, sensory cell damage or loss is irreversible. The understanding of gene and cellular functions, through analysis of different animal models, has helped to identify causes of disease and possible targets for hearing restoration. Translation of these findings to novel therapeutics is, however, hindered by the lack of cellular assays, based on human sensory cells, to evaluate the conservation of molecular pathways across species and the efficacy of novel therapeutic strategies. In the last decade, stem cell technologies enabled to generate human sensory cell types in vitro, providing novel tools to study human inner ear biology, model disease, and validate therapeutics. This review focuses specifically on two technologies: directed differentiation of pluripotent stem cells and direct reprogramming of somatic cell types to sensory hair cells and neurons. Recent development in the field are discussed as well as how these tools could be implemented to become routinely adopted experimental models for hearing research.
Activin A-derived human embryonic stem cells show increased competence to differentiate into primordial germ cell-like cells
Authors: Mishra Swati , Taelman Jasin , Popovic Mina , Tilleman Laurentijn , Duthoo Evi , Jeught Margot , Deforce Dieter , Nieuwerburgh Filip , Menten Björn , Sutter Petra , Boel Annekatrien , Chuva De Sousa Lopes Susana M. , Heindryckx Björn
Published: May 2021

Protocols for specifying human primordial germ cell-like cells (hPGCLCs) from human embryonic stem cells (hESCs) remain hindered by differences between hESC lines, their derivation methods, and maintenance culture conditions. This poses significant challenges for establishing reproducible in vitro models of human gametogenesis. Here, we investigated the influence of activin A (ActA) during derivation and maintenance on the propensity of hESCs to differentiate into PGCLCs. We show that continuous ActA supplementation during hESC derivation (from blastocyst until the formation of the post-inner cell mass intermediate [PICMI]) and supplementation (from the first passage of the PICMI onwards) is beneficial to differentiate hESCs to PGCLCs subsequently. Moreover, comparing isogenic primed and naïve states prior to differentiation, we showed that conversion of hESCs to the 4i-state improves differentiation to (TNAP [tissue nonspecific alkaline phosphatase]+/PDPN [podoplanin]+) PGCLCs. Those PGCLCs expressed several germ cell markers, including TFAP2C (transcription factor AP-2 gamma), SOX17 (SRY-box transcription factor 17), and NANOS3 (nanos C2HC-type zinc finger 3), and markers associated with germ cell migration, CXCR4 (C-X-C motif chemokine receptor 4), LAMA4 (laminin subunit alpha 4), ITGA6 (integrin subunit alpha 6), and CDH4 (cadherin 4), suggesting that the large numbers of PGCLCs obtained may be suitable to differentiate further into more mature germ cells. Finally, hESCs derived in the presence of ActA showed higher competence to differentiate to hPGCLC, in particular if transiently converted to the 4i-state. Our work provides insights into the differences in differentiation propensity of hESCs and delivers an optimized protocol to support efficient human germ cell derivation.
Engineering-inspired approaches to study β-cell function and diabetes
Authors: Lewis Phillip L. , Wells James M.
Published: May 2021

Strategies to mitigate the pathologies from diabetes range from simply administering insulin to prescribing complex drug/biologic regimens combined with lifestyle changes. There is a substantial effort to better understand β-cell physiology during diabetes pathogenesis as a means to develop improved therapies. The convergence of multiple fields ranging from developmental biology to microfluidic engineering has led to the development of new experimental systems to better study complex aspects of diabetes and β-cell biology. Here we discuss the available insulin-secreting cell types used in research, ranging from primary human β-cells, to cell lines, to pluripotent stem cell-derived β-like cells. Each of these sources possess inherent strengths and weaknesses pertinent to specific applications, especially in the context of engineered platforms. We then outline how insulin-expressing cells have been used in engineered platforms and how recent advances allow for better mimicry of in vivo conditions. Chief among these conditions are β-cell interactions with other endocrine organs. This facet is beginning to be thoroughly addressed by the organ-on-a-chip community, but holds enormous potential in the development of novel diabetes therapeutics. Furthermore, high throughput strategies focused on studying β-cell biology, improving β-cell differentiation, or proliferation have led to enormous contributions in the field and will no doubt be instrumental in bringing new diabetes therapeutics to the clinic.
A mechanoresponsive PINCH-1-Notch2 interaction regulates smooth muscle differentiation of human placental mesenchymal stem cells
Authors: Su Jie , Guo Ling , Wu Chuanyue
Published: May 2021

Extracellular matrix (ECM) stiffness plays an important role in the decision making process of smooth muscle differentiation of mesenchymal stem cells (MSCs) but the underlying mechanisms are incompletely understood. Here we show that a signaling axis consisting of PINCH-1 and Notch2 is critically involved in mediating the effect of ECM stiffness on smooth muscle differentiation of MSCs. Notch2 level is markedly increased in ECM stiffness-induced smooth muscle differentiation of human placental MSCs. Knockdown of Notch2 from human placental MSCs effectively inhibits ECM stiffness-induced smooth muscle differentiation, whereas overexpression of North intracellular domain (NICD2) is sufficient to drive human placental MSC differentiation toward smooth muscle cells. At the molecular level, Notch2 directly interacts with PINCH-1. The interaction of Notch2 with PINCH-1 is significantly increased in response to ECM stiffness favoring smooth muscle differentiation. Furthermore, depletion of PINCH-1 from human placental MSCs reduces Notch2 level and consequently suppresses ECM stiffness-induced smooth muscle differentiation. Re-expression of PINCH-1, but not that of a Notch2-binding defective PINCH-1 mutant, in PINCH-1 knockdown human placental MSCs restores smooth muscle differentiation. Finally, overexpression of NICD2 is sufficient to override PINCH-1 deficiency-induced defect in smooth muscle differentiation. Our results identify an ECM stiffness-responsive PINCH-1-Notch2 interaction that is critically involved in ECM stiffness-induced smooth muscle differentiation of human placental MSCs.
The Science of Reading Comprehension Instruction
Authors: Duke Nell K. , Ward Alessandra E. , Pearson P. David
Published: May 2021

Decades of research offer important understandings about the nature of comprehension and its development. Drawing on both classic and contemporary research, in this article, we identify some key understandings about reading comprehension processes and instruction, including these: Comprehension instruction should begin early, teaching word‐reading and bridging skills (including graphophonological semantic cognitive flexibility, morphological awareness, and reading fluency) supports reading comprehension development, reading comprehension is not automatic even when fluency is strong, teaching text structures and features fosters reading comprehension development, comprehension processes vary by what and why we are reading, comprehension strategy instruction improves comprehension, vocabulary and knowledge building support reading comprehension development, supporting engagement with text (volume reading, discussion and analysis of text, and writing) fosters comprehension development, and instructional practices that kindle reading motivation improve comprehension. We present a visual depiction of this model, emphasizing the layered nature of impactful comprehension instruction.
Picturebook Biography Read‐Alouds and Standards for Mathematical Practice
Authors: Young Terrell A. , Monroe Eula Ewing , Roth‐McDuffie Amy
Published: May 2021

Read‐alouds of picturebook biographies offer children engaging windows into the lives and work of famous (and sometimes not‐so‐famous) mathematicians to observe and discuss their ways of learning and doing mathematics—their mathematical practices. The Standards for Mathematical Practice (SMPs), although generally embodied in the work of successful mathematicians throughout the ages, were only recently identified and prescribed for US mathematics curricula. The authors provide a rationale for using the context of story to introduce the SMPs to elementary students and share picturebook Read‐Aloud Lesson Ideas as samples for inviting discussions about selected Standards. Three figures list additional biographies in the categories of Computer Science and Coding, Space Exploration, and Other Related Mathematics Fields and provide an analysis of two selected SMPs for each book.
Synthesis of Palladium complexes derived from Amido linked N‐Heterocyclic Carbenes and their use in Suzuki cross coupling reactions
Authors: Chauhan Rohit Singh , Nagar Suryakant , Chatterjee Sucheta , Goswami Dibakar , Cordes David B. , Slawin Alexandra M. Z. , Tawde Trupti
Published: May 2021

Treatment of 1‐(n‐butyl)‐3‐N‐(2‐Ar)acetamido‐1, 3‐imidazolium chloride (Ar=furylmethyl,phenylmethyl) with excess K2CO3 and [PdCl2(L−L)] (L−L=2 PPh3, dppf) afforded orange compounds of composition [(1‐(n‐butyl)‐3‐N‐(2‐Ar)acetamido‐1,3‐imidazol‐2‐ylidene)]2Pd (Ar=furylmethyl; phenylmethyl). These complexes were characterized by NMR (1H and 13C{1H} NMR), IR and micro‐analysis data. Subsequently, the catalytic efficiency of these complexes for cross coupling reactions between 4‐haloarenens (halo=Br, I) and phenylboronic acid was studied under different solvents (acetonitrile, THF and DMF), temperatures with different catalyst loadings. The molecular structure of [(1‐(n‐butyl)‐3‐N‐(2‐furylmethyl)acetamido‐1, 3‐imidazol‐2‐ylidene)]2Pd was established by single crystal X‐ray diffraction analysis.
Symplectic resolutions of quiver varieties
Authors: Bellamy Gwyn , Schedler Travis
Published: May 2021

In this article, we consider Nakajima quiver varieties from the point of view of symplectic algebraic geometry. We prove that they are all symplectic singularities in the sense of Beauville and completely classify which admit symplectic resolutions. Moreover we show that the smooth locus coincides with the locus of canonically $$\theta $$
θ
-polystable points, generalizing a result of Le Bruyn; we study their étale local structure and find their symplectic leaves. An interesting consequence of our results is that not all symplectic resolutions of quiver varieties appear to come from variation of GIT.
$$L^p$$-trace-free version of the generalized Korn inequality for incompatible tensor fields in arbitrary dimensions
Authors: Lewintan Peter , Neff Patrizio
Published: May 2021

For$$n\ge 3$$n≥3and$$1<p<\infty $$1<p<∞, we prove an$$L^p$$Lp-version of the generalized trace-free Korn-type inequality for incompatible,p-integrable tensor fields$$P:\Omega \rightarrow \mathbb {R}^{n\times n}$$P:Ω→Rn×nhavingp-integrable generalized$${\text {Curl}}_{n}$$Curlnand generalized vanishing tangential trace$$P\,\tau _l=0$$Pτl=0on$$\partial \Omega $$∂Ω, denoting by$$\{\tau _l\}_{l=1,\ldots , n-1}$${τl}l=1,…,n-1a moving tangent frame on$$\partial \Omega $$∂Ω. More precisely, there exists a constant$$c=c(n,p,\Omega )$$c=c(n,p,Ω)such that$$\begin{aligned} \Vert P \Vert _{L^p(\Omega ,\mathbb {R}^{n\times n})}\le c\,\left( \Vert {\text {dev}}_n {\text {sym}}P \Vert _{L^p(\Omega ,\mathbb {R}^{n \times n})}+ \Vert {\text {Curl}}_{n} P \Vert _{L^p\left( \Omega ,\mathbb {R}^{n\times \frac{n(n-1)}{2}}\right) }\right) , \end{aligned}$$‖P‖Lp(Ω,Rn×n)≤c‖devnsymP‖Lp(Ω,Rn×n)+‖CurlnP‖LpΩ,Rn×n(n-1)2,where the generalized$${\text {Curl}}_{n}$$Curlnis given by$$({\text {Curl}}_{n} P)_{ijk} :=\partial _i P_{kj}-\partial _j P_{ki}$$(CurlnP)ijk:=∂iPkj-∂jPkiand "Equation missing"denotes the deviatoric (trace-free) part of the square matrixX. The improvement towards the three-dimensional case comes from a novel matrix representation of the generalized cross product.
Phase II study of trifluridine/tipiracil (TAS-102) therapy in elderly patients with colorectal cancer (T-CORE1401): geriatric assessment tools and plasma drug concentrations as possible predictive biomarkers
Authors: Takahashi Masanobu , Sakamoto Yasuhiro , Ohori Hisatsugu , Tsuji Yasushi , Kuroki Michio , Kato Satoshi , Otsuka Kazunori , Komine Keigo , Takahashi Masahiro , Takahashi Shin , Shirota Hidekazu , Ouchi Kota , Takahashi Yoshikazu , Imai Hiroo , Shibata Hiroyuki , Yoshioka Takashi , Tanaka Masaki , Yamaguchi Hiroaki , Yamaguchi Takuhiro , Shimodaira Hideki , Ishioka Chikashi
Published: May 2021

Purpose

The current study aimed to determine the efficacy of trifluridine/tipiracil for elderly patients with advanced colorectal cancer.

Methods

This single-arm, open-label, multicenter, phase II study included elderly patients aged 65 years or more who had fluoropyrimidine-refractory advanced colorectal cancer and received trifluridine/tipiracil (70 mg/m2, days 1–5 and 8–12, every 4 weeks). The primary endpoint was progression-free survival (PFS), while secondary endpoints included overall survival (OS), overall response rate (ORR), toxicities, association between efficacy and geriatric assessment scores, and association between toxicity and plasma drug concentrations.

Results

A total of 30 patients with a mean age of 73 years were enrolled. Median PFS was 2.3 months (95% confidence interval, 1.9–4.3 months), while median OS was 5.7 months (95% confidence interval, 3.7–8.9 months). Patients had an ORR of 0%, with 57% having stable disease. Grade 4 neutropenia was observed in 13% of the patients. Patients with a higher G8 score (15 or more) showed longer PFS than those with a lower G8 score (median 4.6 vs. 2.0 months; p = 0.047). Moreover, patients with grade 3 or 4 neutropenia showed higher maximum trifluridine concentrations than those with grade 1 or 2 neutropenia (mean 2945 vs. 2107 ng/mL; p = 0.036).

Discussion

The current phase II trial demonstrated that trifluridine/tipiracil was an effective and well-tolerated option for elderly patients with advanced colorectal cancer. Moreover, geriatric assessment tools and/or plasma drug concentration monitoring might be helpful in predicting the efficacy and toxicities in elderly patients receiving this drug.

Trial registration number

UMIN000017589, 15/May/2015 (The University Hospital Medical Information Network)
A novel gaze-controlled flexible robotized endoscope; preliminary trial and report
Authors: Sivananthan Arun , Kogkas Alexandros , Glover Ben , Darzi Ara , Mylonas George , Patel Nisha
Published: May 2021

Background

Interventional endoluminal therapy is rapidly advancing as a minimally invasive surgical technique. The expanding remit of endoscopic therapy necessitates precision control. Eye tracking is an emerging technology which allows intuitive control of devices. This was a feasibility study to establish if a novel eye gaze-controlled endoscopic system could be used to intuitively control an endoscope.

Methods

An eye gaze-control system consisting of eye tracking glasses, specialist cameras and a joystick was used to control a robotically driven endoscope allowing steering, advancement, withdrawal and retroflexion. Eight experienced and eight non-endoscopists used both the eye gaze system and a conventional endoscope to identify ten targets in two simulated environments: a sphere and an upper gastrointestinal (UGI) model.

Completion of tasks was timed. Subjective feedback was collected from each participant on task load (NASA Task Load Index) and acceptance of technology (Van der Laan scale).

Results

When using gaze-control endoscopy, non-endoscopists were significantly quicker when using gaze-control rather than conventional endoscopy (sphere task 3:54 ± 1:17 vs. 9:05 ± 5:40 min, p = 0.012, and UGI model task 1:59 ± 0:24 vs 3:45 ± 0:53 min, p < .001).

Non-endoscopists reported significantly higher NASA-TLX workload total scores using conventional endoscopy versus gaze-control (80.6 ± 11.3 vs 22.5 ± 13.8, p < .001). Endoscopists reported significantly higher total NASA-TLX workload scores using gaze control versus conventional endoscopy (54.2 ± 16 vs 26.9 ± 15.3, p = 0.012). All subjects reported that the gaze-control had positive ‘usefulness’ and ‘satisfaction’ score of 0.56 ± 0.83 and 1.43 ± 0.51 respectively.

Conclusions

The novel eye gaze-control system was significantly quicker to use and subjectively lower in workload when used by non-endoscopists. Further work is needed to see if this would translate into a shallower learning curve to proficiency versus conventional endoscopy. The eye gaze-control system appears feasible as an intuitive endoscope control system. Hybrid gaze and hand control may prove a beneficial technology to evolving endoscopic platforms.
Local Ceramics from the Islamic Trade Center of Harlaa, Eastern Ethiopia: Markers of Chronology and Contacts
Authors: Tait Nicholas , Insoll Timothy
Published: May 2021

Locally made ceramics from Islamic sites in Ethiopia have been neglected in most archaeological studies, which tend to privilege imported Middle Eastern and Chinese/Southeast Asian ceramics. An assemblage of the local ceramics from the important trading site of Harlaa, in eastern Ethiopia (mid-sixth and fifteenth centuries AD), is the subject of this article. The study emphasizes the value of these ceramics as chronological markers, and for understanding regional and long-distance contacts, cultural innovations, processes of Islamization, and foodways.
Characterization of the heterogeneity of endothelial cells in bleomycin-induced lung fibrosis using single-cell RNA sequencing
Authors: Liu Xiucheng , Qin Xichun , Qin Hao , Jia Caili , Yuan Yanliang , Sun Teng , Chen Bi , Chen Chang , Zhang Hao
Published: May 2021

The loss of normal alveolar capillary and deregulated angiogenesis occurs simultaneously in idiopathic pulmonary fibrosis (IPF); however the contributions of specific endothelial subpopulations in the development of pulmonary fibrosis are poorly understood. Herein, we perform single-cell RNA sequencing to characterize the heterogeneity of endothelial cells (ECs) in bleomycin (BLM)-induced lung fibrosis in rats. One subpopulation, characterized by the expression of Nos3 and Cav1, is mostly distributed in non-fibrotic lungs and also highly expresses genes related to the “response to mechanical stimulus” and “lung/heart morphogenesis” processes. Another subpopulation of ECs expanded in BLM-treated lungs, characterized by Cxcl12, is observed to be closely related to the pro-fibrotic process in the transcriptome data, such as “regulation of angiogenesis,” “collagen binding,” and “chemokine activity,” and spatially localized to BLM-induced neovascularization. Using CellPhoneDB software, we generated a complex cell–cell interaction network, which predicts the potential roles of EC subpopulations in recruiting monocytes, inducing the proliferation of fibroblasts and promoting the production and remolding of the extracellular matrix (ECM). Taken together, our data demonstrate the high degree of heterogeneity of ECs in fibrotic lung and it is proposed that the interaction between ECs, macrophages, and stromal cells contributes to pathologic IPF.
Can methods of artificial intelligence aid in optimizing patient selection in patients undergoing intrauterine inseminations?
Authors: Kozar Nejc , Kovač Vilma , Reljič Milan
Published: May 2021

Purpose

AI and its machine learning algorithms have proven useful in several fields of medicine, including medically assisted reproduction. The purpose of the study was to construct several predictive models based on clinical data and select the best models to predict IUI procedure outcomes.

Methods

Clinical data (patient baseline characteristics, sperm quality, hormonal status, and cycle data) from 1029 IUI procedures performed in 413 couples stimulated by clomiphene citrate, letrozole, or gonadotropins were used to build several models to predict clinical pregnancy. The models included ANN, random forest, PLS, SVM, and linear models using the caret package in R. The models were evaluated using ROC analysis by means of random CV on test data.

Results

Out of the best performing models, the random forest model achieved an AUC of 0.66, a sensitivity of 0.432, and a specificity of 0.756. This performance was followed by the PLS model, which achieved a sensitivity of 0.459 and specificity of 0.734. The other models achieved significantly lower AUCs. When adjusting the predictive cutoff value, confusion matrices show that clinical pregnancy is twice as likely in the case of positive prediction.

Conclusion

Among the compared methods, the random forest and PLS models demonstrated superior performance in predicting the clinical outcome of IUI. With additional research and clinical validation, AI methods may be successfully used in improving patient selection and consequently lead to better clinical results.
Binding free energy predictions in host-guest systems using Autodock4. A retrospective analysis on SAMPL6, SAMPL7 and SAMPL8 challenges
Authors: Casbarra Lorenzo , Procacci Piero
Published: May 2021

We systematically tested the Autodock4 docking program for absolute binding free energy predictions using the host-guest systems from the recent SAMPL6, SAMPL7 and SAMPL8 challenges. We found that Autodock4 behaves surprisingly well, outperforming in many instances expensive molecular dynamics or quantum chemistry techniques, with an extremely favorable benefit-cost ratio. Some interesting features of Autodock4 predictions are revealed, yielding valuable hints on the overall reliability of docking screening campaigns in drug discovery projects.
Changes in the identity of the teaching profession: A study of a teacher union in Sweden from 1990 to 2017
Authors: Krantz Joakim , Fritzén Lena
Published: May 2021

We analyse changes in the collective identity that Sweden’s largest labour union for teachers had during the period 1990–2017. The study is based on theory about how collective identity is constructed in adaptation and resistance to external categorical dimensions and internal group identification. We identify shifts in relation to how the union employ different aspects on teachers' recognition, emotional engagement, and evaluation. Two clear cut-off points can be identified. The first point, which is clearly related to the impact of political reforms, took place in 2000 and is about increased demands with respect to transparency, legality, equality, efficiency, and attainment results. The second point took place in 2015, a year when Sweden confronted a new set of social challenges. The teaching profession was re-launched as a moral agent and in need of a trust-based steering approach.
Orthonormal systems in spaces of number theoretical functions
Authors: Indlekofer Karl-Heinz , Kaya Erdener , Wagner Robert
Published: May 2021

In this paper, we consider some examples of set algebras $$ \mathcal{A} $$
A
on ℕ. If ℰ($$ \mathcal{A} $$
A
) is the set of simple functions on $$ \mathcal{A} $$
A
, then ℒ∗α($$ \mathcal{A} $$
A
) denotes the ‖⋅‖ α-closure of ℰ($$ \mathcal{A} $$
A
). Our aim is to determine a complete orthonormal system for the Hilbert space ℒ∗2($$ \mathcal{A} $$
A
) in each regarded case. Here ℒ∗2($$ \mathcal{A} $$
A
) denotes the quotient space ℒ∗2($$ \mathcal{A} $$
A
) modulo null-functions.
Multi-objective Optimization of Kerf-taper and Surface-roughness Quality Characteristics for Cutting-operation On Coir and Carbon Fibre Reinforced Epoxy Hybrid Polymeric Composites During CO2-Pulsed Laser-cutting Using RSM
Authors: Singh Yadvinder , Singh Jujhar , Sharma Shubham , Aggarwal Vivek , Pruncu Catalin I.
Published: May 2021

Current research focuses on optimizing various quality characteristics for kerf geometry generated through laser cutting of Coir fibre/carbon fibre/epoxy resin hybrid composite adjacent to straight cut profile employing pulsed CO2 laser system. The Kerf taper (KT) and the Surface roughness (SR) are the main quality parameters discussed. Dependent on significant process parameters, namely gas pressure, cutting speed, pulse frequency and pulse width predictive models were developed. In accordance with Taguchi's L9 orthogonal array (OA), the cutting trials are designed. Process-parametric optimization was performed using Response Surface Methodology (RSM). Furthermore, experiments were performed to obtain experimental data for the analysis of cut quality features. The impact of the input variables on the response characteristics is also explored. The morphological characterizations have been performed to analysis the effect of machining-variables and cut-quality for the top and bottom kerf widths with various laser cutting variables in the pulse laser-cutting of Coir-fibre/carbon-fibre/epoxy-resin hybrid composite. For SR and KT, the developed second order surface response model was found very successful. The optimal levels of cutting variables for KT are established at Gas pressure-6 N/mm2, pulse width-2.04 ms, cutting speed-8.01 mm/s, pulse frequency-15 Hz, for sample A1, Gas pressure-5.47 N/mm2, pulse width-2.5 ms, cutting speed-8.81 mm/s, pulse frequency-8.43 Hz, for sample A2, Gas pressure-3.85 N/mm2, pulse width-1.5 ms, cutting speed-9.06 mm/s, pulse frequency-5 Hz, for sample A3 additionally for SR Gas pressure-2 N/mm2, pulse width-1.5 ms, cutting speed-7 mm/s, pulse frequency-5 Hz, for sample A1, Gaspressure-2.36 N/mm2, pulse width-1.5 ms, cutting speed-7 mm/s, pulse frequency-15 Hz, for sample A2, Gaspressure-6 N/mm2, pulse width-1.5 ms, cutting speed-11 mm/s, pulse frequency-8.73 Hz, for sample A3. Regression results and linear and square impact of laser cutting variables have been revealed to be important to validate the model.
The MBARI-WEC: a power source for ocean sensing
Authors: Hamilton Andrew , Cazenave François , Forbush Dominic , Coe Ryan G. , Bacelli Giorgio
Published: May 2021

Interest in wave energy converters to provide autonomous power to various ocean-bound systems, such as autonomous underwater vehicles, sensor systems, and even aquaculture farms, has grown in recent years. The Monterey Bay Aquarium Research Institute has developed and deployed a small two-body point absorber wave energy device suitable to such needs. This paper provides a description of the system to support future open-source access to the device and further the general development of similar wave energy systems. Additionally, to support future control design and system modification efforts, a set of hydrodynamic models are presented and cross-compared. To test the viability of using a linear frequency-domain admittance model for controller tuning, the linear model is compared against four WEC-Sim models of increasing complexity. The linear frequency-domain model is found to be generally adequate for capturing system dynamics, as the model agreement is good and the degree of nonlinearity introduced in the WEC-Sim models is generally less than 2.5%.
A Dynamic Factor and Neural Networks Analysis of the Co-movement of Public Revenues in the EMU
Authors: Magazzino Cosimo , Mele Marco
Published: May 2021

This paper shows that the co-movement of public revenues in the European Monetary Union (EMU) is driven by an unobserved common factor. Our empirical analysis uses yearly data covering the period 1970–2014 for 12 selected EMU member countries. We have found that this common component has a significant impact on public revenues in the majority of the countries. We highlight this common pattern in a dynamic factor model (DFM). Since this factor is unobservable, it is difficult to agree on what it represents. We argue that the latent factor that emerges from the two different empirical approaches used might have a composite nature, being the result of both the more general convergence of the economic cycles of the countries in the area and the increasingly better tuned tax structure. However, the original aspect of our paper is the use of a back-propagation neural networks (BPNN)-DF model to test the results of the time-series. At the level of computer programming, the results obtained represent the first empirical demonstration of the latent factor’s presence.
Digital twins: artificial intelligence and the IoT cyber-physical systems in Industry 4.0
Authors: Radanliev Petar , De Roure David , Nicolescu Razvan , Huth Michael , Santos Omar
Published: May 2021

This paper presents a summary of mechanisms for the evolution of artificial intelligence in ‘internet of things’ networks. Firstly, the paper investigates how the use of new technologies in industrial systems improves organisational resilience supporting both a technical and human level. Secondly, the paper reports empirical results that correlate academic literature with Industry 4.0 interdependencies between edge components to both external and internal services and systems. The novelty of the paper is a new approach for creating a virtual representation operating as a real-time digital counterpart of a physical object or process (i.e., digital twin) outlined in a conceptual diagram. The methodology applied in this paper resembled a grounded theory analysis of complex interconnected and coupled systems. By connecting the human–computer interactions in different information knowledge management systems, this paper presents a summary of mechanisms for the evolution of artificial intelligence in internet of things networks.
A computational study on the uncertainty quantification of failure of clays with a modified Cam-Clay yield criterion
Authors: Savvides Ambrosios A. , Papadrakakis Manolis
Published: May 2021

In this study, the quantitative effect of the random distribution of the soil material properties to the probability density functions of the failure load and displacements is presented. A modified Cam-Clay failure criterion is embedded into a stochastic finite element numerical tool for this purpose. Various assumptions for the random distribution of the compressibility factor $$\kappa$$
κ
, of the constitutive relation, the critical state line inclination c of the soil, and the permeability k have been tested and assessed with Latin hypercube sampling followed by Monte Carlo simulation. It is confirmed that both failure load and displacements follow Gaussian normal distribution despite the nonlinearity of the problem. Moreover, as the soil depth increases the mean value of failure load decreases and the failure displacement increases. Consequently, failure mechanism of clays can be determined in this work within an acceptable variability, taking into account the soil depth and nonlinear constitutive relations which in the analytical solutions is not feasible as it is assumed the Meyerhoff theory which considers the elastic halfspace.
Heavy metal concentrations in the edible portions of Centella asiatica: Health risk toward chronic kidney disease of uncertain etiology
Authors: Wijeyaratne W. M. Dimuthu Nilmini , Kumari Ellewaththe Arachchilage Charuni Se
Published: May 2021

Centella asiaticais a commonly consumed green leafy vegetable in many developing countries due its high nutritious value and availability at low cost. The present study was conducted to assess the Cd, Cr and Pb uptake associated health risks ofCentella asiaticaharvested from organic and non-organic cultivations in a chronic kidney disease of uncertain etiology (CKDue) prevalent area in Sri Lanka. The health risk assessment was conducted in terms of the bioconcentration factor (BCF), soil-to-root and root-to-leaf translocation factors ($${\text{TF}}\,({\text{soil-root}})$$TF(soil-root)and$${\text{TF}}\,({\text{root-leaf}})$$TF(root-leaf)), Target hazard quotient for each heavy metal (THQ) and hazard index (HI). In addition, the spatial variation of physical and chemical parameters of the root zone soil were assessed using MINITAB 17 statistical software. Results indicated significant spatial variations in conductivity, organic matter content and Cr concentrations among organic and non-organic study sites. The Cr, Cd and Pb concentrations recorded from roots and leaves ofCentella asiaticawere higher than the safe limits for consumption established by the European Union. The health risk analysis indicated that there is a potential of hyper-accumulating Cd in the roots ofCentella asiatica. Further, the THQ and HI of the heavy metals indicated possible adverse non-cancer health risks associated with long-term consumption of leaves ofCentella asiatica. Therefore, necessary precautionary actions to prevent the excessive buildup of Cr, Cd and Pb in the edible portions ofCentella asiaticaare essential in order to ensure consumer safety.
A framework for systemic sustainable construction industry development (SSCID)
Authors: Gyadu-Asiedu William , Ampadu-Asiamah Adwoa , Fokuo-Kusi Alfred
Published: May 2021

The quest for construction industry (CI) development in developing countries has met with several challenges. These challenges are numerous and varied. The study aimed to provide a framework by which the construction industry development agenda in developing countries could be prosecuted through a more structured and systemic approach. The qualitative research approach was adopted for the study. This approach was employed within the constructivist epistemological paradigm. Regarding information gathering, the study used the integrative literature review approach to elucidate the construction industry’s nature and its proper systemic context. Complexity, interconnectedness, fragmentation, culture, and informality were found to be common challenges inherent in most CIs. Concerning the development of the industry, the approach was to (1) consider the industry as a system of systems (enabling the use of the principles of systems thinking and systems engineering), (2) apply the concepts of sustainable development as considered within the sustainable development goals (SDGs) and specified in the triple-bottom-line (TBL), i.e., the economic, environmental, and social dimensions, (3) identify the components of CI development (eight components were identified), which are: technology development, corporate development, human resource development, institutional development, material development, documentation, practice and procedure, and operating environment), and (4) Integrated studies. A conceptual framework was modelled from all the identified constructs. Based on this model, it was possible to propose a framework for assessing the maturity level of a country's sustainable construction industry development  and, thereby,  monitor its systemic development.
The role of basic psychological needs in bullying victimisation in the family and at school
Authors: Varsamis Panagiotis , Halios Helias , Katsanis Georgios , Papadopoulos Apostolos
Published: May 2021

Bullying continuously attracts the interest of school communities, government policy makers and researchers. The present study enquires into the role of basic psychological needs in perpetrating and victimisation behaviour of children and youth in the social contexts of school and family in a cross-sectional research design. Specifically, this study focuses on the direct effects that basic psychological needs might have on bullying behaviour and bullying victimisation. It was found that basic psychological needs, forged in the relationships with family and school members, could predict bullying victimisation in each social context. Bullying perpetrations could be predicted only by bullying victimisation stemming from each social context, whereas bullying behaviours in school could also be directly predicted by the basic psychological needs developed in the family. Furthermore, path models verified the multiple influences of family functioning on school relationships. Findings of the present study may contribute to designing effective school interventions and to reforming antibullying guidelines for teachers and parents with respect to the basic psychological needs of the children or adolescents who have been victimised.
Spiraling solutions of nonlinear Schrödinger equations
Authors: Agudelo Oscar , Kübler Joel , Weth Tobias
Published: May 2021

We study a new family of sign-changing solutions to the stationary nonlinear Schrödinger equation
\[ -\Delta v +q v =|v|^{p-2} v, \qquad \text{in}\,{ {\mathbb{R}^{3}},} \]
with $2 < p < \infty$ and $q \ge 0$. These solutions are spiraling in the sense that they are not axially symmetric but invariant under screw motion, i.e., they share the symmetry properties of a helicoid. In addition to existence results, we provide information on the shape of spiraling solutions, which depends on the parameter value representing the rotational slope of the underlying screw motion. Our results complement a related analysis of Del Pino, Musso and Pacard in their study (2012, Manuscripta Math., 138, 273–286) for the Allen–Cahn equation, whereas the nature of results and the underlying variational structure are completely different.
Does the Meeting Style Matter? The Effects of Exposure to Participatory and Deliberative School Board Meetings
Authors: COLLINS JONATHAN E.
Published: May 2021

Would public meetings incite more civic engagement if they were structured in ways that are simply more engaging? I addressed this question by conducting an original survey with an oversample of racial and ethnic minorities and individuals from low-income households. The survey featured a randomized experiment in which each study participant was shown a short clip of an actual school board meeting that was (1) a standard meeting with no public participation, (2) a meeting with public participation, or (3) a meeting with deliberation (public participation followed by a reasoned response from the school board). The experience of viewing the more participatory and deliberative school board meetings led to increased trust in local officials and a stronger willingness to attend school board meetings in the future. This study has significant implications for civic engagement, local politics, and public school governance.
SOLUTIONS TO A LEBESGUE–NAGELL EQUATION
Authors: THO NGUYEN XUAN
Published: May 2021

We find all integer solutions to the equation
$x^2+5^a\cdot 13^b\cdot 17^c=y^n$
with
$a,\,b,\,c\geq 0$
,
$n\geq 3$
,
$x,\,y>0$
and
$\gcd (x,\,y)=1$
. Our proof uses a deep result about primitive divisors of Lucas sequences in combination with elementary number theory and computer search.
Plant-based dietary indices and stress in female college students: a cross-sectional study
Authors: Aljuraiban Ghadeer S.
Published: May 2021

Only a few studies have investigated the association between psychological stress and the healthfulness of plant-based diets while accounting for variances in age groups and regions. In light of this, this study aimed to identify the food groups that contribute the most to the relationship between the healthfulness of plant-based diets and psychological stress in female students in Saudi Arabia. This cross-sectional study, which included 401 female college students aged 19–35 years, collected data on blood, anthropometric indices, the perceived stress scale-10 (PSS-10) and diet using the Saudi food frequency questionnaire. An overall plant-based diet index (PDI), healthy PDI, and an unhealthy PDI (uPDI) were defined. Multiple linear regression analyses were applied to examine the associations between PSS-10 and PDI and hPDI and uPDI. No associations between the PSS-10 score and the overall PDI or uPDI scores were found; however, a six-point higher hPDI score was associated with a 0·16-point lower PSS-10 score (95 % CI, –0·24, –0·08) after controlling for lifestyle factors. Moreover, adjustments for healthy food groups, including vegetables and fruits, attenuated the association between the hPDI and PSS-10. In conclusion, healthy plant-based diets are associated with lower psychological stress in young Saudi women. This finding highlights the importance, especially for female students, of following diets that are not only plant-based but are also healthy and rich in fruits and vegetables.
Kidney function decline is associated with an accelerated increase in plasma homocysteine in older adults: a longitudinal study
Authors: Zhang Hui , Li Yi , Hao Meng , Jiang Xiaoyan , Wang Jiucun , Jin Li , Bao Zhijun , Wang Xiaofeng
Published: May 2021

Few studies have been conducted to investigate the association of kidney function decline with the trajectories of homocysteine (Hcy) over time, using repeated measurements. We aimed to investigate the association of kidney function with changes in plasma Hcy levels over time. Data were collected from the Rugao Longevity and Ageing Study. In detail, plasma Hcy and creatinine levels were measured in both waves (waves 2, 3 and 4) during the 3·5-year follow-up (n 1135). Wave 2 was regarded as the baseline survey. The estimated glomerular filtration rate (eGFR) was calculated based on creatinine. Subjects were categorised into four groups according to quartiles of eGFR at baseline. Linear mixed-effect models were used to investigate the association of eGFR with subsequent plasma Hcy levels. The mean eGFR at baseline was 90·84 (sd 11·42) ml/min per 1·73 m2. The mean plasma Hcy level was 14·09 (sd 6·82) at baseline and increased to 16·28 (sd 8·27) and 17·36 (sd 10·39) μmol/l during follow-ups. In the crude model, the interaction between time and eGFR at baseline was significant (β = −0·02, 95 % CI −0·02, −0·01, P = 0·002). After adjusting for confounding factors, a significant relationship remained (β = −0·02, 95 % CI −0·02, −0·01, P = 0·003), suggesting that kidney function decline at baseline was associated with a faster increase in Hcy levels. Kidney function decline is associated with a more pronounced increase in plasma Hcy levels. Further studies with longer follow-up periods and larger sample sizes are needed to validate our findings.