bluuebunny/crossref_metadata_2025 huggingface dataset:
Avoiding module capacitance over-dimensioning of Modular Multilevel Converters with constrained and unconstrained modulator-based Model Predictive Control
Authors: Fuchs Simon , Biela Jürgen
Published: February 2023

The power density of Modular Multilevel Converters (MMCs) is often limited by the over-dimensioning of the module capacitance value. This is common because with conventional control schemes, large voltage and energy margins must be included in the MMC design to avoid overvoltages in the module capacitors and saturation effects due to undervoltages in the module capacitors. This paper presents two Model Predictive Control methods that can reduce the necessary voltage and energy margins to a minimum and therefore increase the power density of the MMC system compared to conventionally controlled MMCs. A trade-off between computational effort and module capacitance over-dimensioning is discovered for the proposed constrained MPC. The unconstrained MPC is compared to the constrained MPC and conventional PI control using simulations. Finally, the performance of the unconstrained MPC is experimentally verified with an MMC system prototype and compared to a traditional PI control system.
Investigations of electrical interference of vertical earth rod arrangements
Authors: Fürnschuß Martin , Pack Stephan , Schmautzer Ernst , Hofbauer Franz , Kowatsch Gernot , Dörfler Jürgen , Schürhuber Robert
Published: February 2023

For the reliable and safe operation of electrical installations, the dissipation of natural and human-made electrical currents into the earth is of great importance. In order to safely dissipate such currents into the earth in a well-controlled manner, blank electrical conductors are specifically inserted into the earth and galvanically connected to the electrical installation. The construct of earth-sensitive conductors (earth electrodes) forms the earthing arrangement. Due to the present conductivity of the earth, galvanically separated earth electrodes interfere electrically through mutual transiting currents. This paper shows geometric arrangements of earth electrodes inserted vertically into the earth, including the effects of the electrical interference on the currents dissipated into the earth, (partial) fault voltages, as well as the resistance to earth by means of calculations. The soil layering and the varying electrical conductivity of the layers are also taken into account. In order to verify the calculations, measurements of the resistances to earth of the vertical earth rods were carried out in a substation in construction.
The effect of a convergent transmucosal neck on soft tissues and radiographic outcomes: a 1-year follow-up randomized controlled trial
Authors: Morón-Conejo Belén , Sanz-Sánchez Ignacio , Salido Maria Paz , Martínez-Rus Francisco , Pradíes Guillermo
Published: February 2023

Purpose

The aim of this randomized controlled clinical trial was to evaluate peri-implant marginal bone levels (MBLs) and soft tissue dimension changes 1 year after loading. Patients in the control group received bone-level implants, whereas in the test group, tissue-level implants with a convergent transmucosal neck were used.

Material and methods

MBLs were calculated by measuring the distance from the implant shoulder to the first visible bone-to-implant contact using standardized periapical digital radiographs. Baseline (day of loading) and follow-up digital models obtained with an intraoral scanner were used to quantify the changes in the peri-implant soft tissue dimensions with a best-fit algorithm.

Results

The difference between final and baseline MBLs showed a mean bone loss of 0.16 ± 0.01 mm in the test group (n = 15) and 0.45 ± 0.09 mm in the control group (n = 14) (p > 0.05). Soft tissue contour at the level of the gingival margin (GM) increased by 1.96 ± 2.69 mm in the test group and 0.65 ± 0.42 mm in the control group (p = 0.167). Both groups showed a coronal displacement of the gingival margin with no significant differences among them.

Conclusions

The present study demonstrated peri-implant hard and soft tissues stability at both implant designs with no significant differences 12 months after loading.

Clinical relevance

There is still insufficient scientific evidence to demonstrate the role and advantages of the convergent transmucosal neck on the behavior of the peri-implant soft and hard tissues stability compared to a straight neck in bone-level implants 12 months after loading.
Pneumatic and acoustic suit: multimodal haptic suit for enhanced virtual reality simulation
Authors: Kang Daeseok , Lee Chang-Gyu , Kwon Ohung
Published: February 2023

A haptic device provides users with physical feedback to enhance their experience in virtual reality (VR). We developed a multimodal haptic suit, called as Pneumatic and Acoustic (PA) suit, which exhibits high-resolution haptic feedback, and applies high pressure and realistic vibration to a user. The PA suit artificially simulates the sensation of brief and strong collisions such as the impact of an explosion, ball, or fist. The pneumatic actuators, consisting of 40 air bladders, are designed as bellows-type pneumatic devices for vertical inflation. The air bladders are placed on the chest at an equal interval distance of 30 mm for high-resolution feedback. The acoustic actuators use an effective sound signal of a collision similar to realistic vibrations. This study aims to examine the effectiveness of our multimodal haptic suit in improving VR experience of users. The recognition tests clearly show that participants distinguish between the haptic patterns and position of collided virtual objects with the suit. The user study involving a collision of a ball shows that the PA suit transmits the approximate pressure of a real ball collision with artificial haptic feedback. Our receiving ball and explosion VR simulations confirm that the PA suit improves a VR experience depending on the types of actuators and VR contents. The results prove that the PA suit creates distinguishable haptic patterns for guiding a task and improves the VR experience of users with powerful and multimodal haptic feedback hence providing high-quality VR simulation.
The effect of snow depth on movement rates of GPS-collared moose
Authors: Melin M. , Matala J. , Mehtätalo L. , Pusenius J. , Packalen T.
Published: February 2023

During deep snow conditions, wildlife must balance between minimizing movements to conserve energy while seeking high amounts of browse to gain the energy. Knowledge of how snow begins to hinder their movements is therefore vital when predicting their wintertime behavior. We assessed the phenomenon with moose. Movement data from 122 GPS-collared moose were integrated with snow depth data from designated measurement stations. The effects of increasing snow depths on moose movement rates were then modeled with spline regression. The study was conducted in Finland, between 2009 and 2011. The moose were known for their sex and for the presence of calf at heel. On average, the movement rates decreased sharply until snow depths of ca. 30–40 cm, after which further significant decreases were not seen. The movement rates decreased from several kilometers per day to less than 500 m per day. Moose in the northernmost study area with the deepest snow covers moved as much as the moose in the other areas with less snow. Although we saw differences in the movement rates between males and females, differences between individuals were markedly higher than those caused by sex or a calf at heel. Moose are keystone species whose heavy browsing, especially during winter, can have profound effects on vegetation and forest regeneration. As snow covers in large parts of the boreal zone are predicted to decrease due to warming climate, the wintertime movements of moose and how they affect the local vegetation will remain relevant questions.
Nonlinear modeling of the ten-story RC building at E-Defense (2015): assessment with different modeling assumptions
Authors: Di Domenico Mariano , Gaetani d’Aragona Marco , Polese Maria , Magliulo Gennaro , Prota Andrea , Verderame Gerardo M. , Kajiwara Koichi
Published: February 2023

Two models of the 10-story reinforced concrete building tested at E-Defense laboratory in 2015 are built: the F model, in which nonlinear behavior is distributed over the element length, and the H model, in which nonlinear behavior is lumped in plastic hinges with a moment-chord rotation response assigned based on empirical formulations proposed in the literature. Nonlinear time–history analyses are performed to reproduce the experimental shaking-table tests performed at increasing seismic intensity level. The incremental experimental test has been performed twice: the first time (BS test), the structure base was free to slip on a concrete base fixed to the shaking table. After the BS test, a second test was performed on the same structure with the foundation fixed to the concrete base (BF test). Both tests are simulated for both models. When simulating both the BS and BF tests, the seismic input adopted for the numerical analyses is the displacement time-history registered at the base of the specimen’s columns, in order to implicitly account for base slip through the input signal without explicitly modeling the slipping devices. It is observed that the significant damage experienced by the specimen during the runs of BF tests at medium–high seismic intensity is probably triggered by softening and damage of beam-column joints: this is reproduced also by H numerical model and highlights the influence of beam-column joints on the overall seismic response of the structure. In general, it is observed that both numerical models, which were constructed, based on experimental data, only by adopting available and well-established tools proposed in the literature, can reproduce the overall response of the case-study structure, especially in terms of maximum top displacement demand and maximum damage state for structural members, provided that beam-column joints’ contribution is adequately considered.
Validation of a breast cancer risk prediction model based on the key risk factors: family history, mammographic density and polygenic risk
Authors: Allman Richard , Mu Yi , Dite Gillian S. , Spaeth Erika , Hopper John L. , Rosner Bernard A.
Published: February 2023

Purpose

We compared a simple breast cancer risk prediction model, BRISK (which includes mammographic density, polygenic risk and clinical factors), against a similar model with more risk factors (simplified Rosner) and against two commonly used clinical models (Gail and IBIS).

Methods

Using nested case–control data from the Nurses’ Health Study, we compared the models’ association, discrimination and calibration. Classification performance was compared between Gail and BRISK for 5-year risks and between IBIS and BRISK for remaining lifetime risk.

Results

The odds ratio per standard deviation was 1.43 (95% CI 1.32, 1.55) for BRISK 5-year risk, 1.07 (95% CI 0.99, 1.14) for Gail 5-year risk, 1.72 (95% CI 1.59, 1.87) for simplified Rosner 10-year risk, 1.51 (95% CI 1.41, 1.62) for BRISK remaining lifetime risk and 1.26 (95% CI 1.16, 1.36) for IBIS remaining lifetime risk. The area under the receiver operating characteristic curve (AUC) was improved for BRISK over Gail for 5-year risk (AUC = 0.636 versus 0.511, P < 0.0001) and for BRISK over IBIS for remaining lifetime risk (AUC = 0.647 versus 0.571, P < 0.0001). BRISK was well calibrated for the estimation of both 5-year risk (expected/observed [E/O] = 1.03; 95% CI 0.73, 1.46) and remaining lifetime risk (E/O = 1.01; 95% CI 0.86, 1.17). The Gail 5-year risk (E/O = 0.85; 95% CI 0.58, 1.24) and IBIS remaining lifetime risk (E/O = 0.73; 95% CI 0.60, 0.87) were not well calibrated, with both under-estimating risk. BRISK improves classification of risk compared to Gail 5-year risk (NRI = 0.31; standard error [SE] = 0.031) and IBIS remaining lifetime risk (NRI = 0.287; SE = 0.035).

Conclusion

BRISK performs better than two commonly used clinical risk models and no worse compared to a similar model with more risk factors.
The Interactional Structure of Accounts During Small Group Discussions Among Autistic Children Receiving Special Education Support in Finland
Authors: Ferreira Juliene Madureira , Bottema-Beutel Kristen
Published: February 2023

Through a conversation analytic approach, we investigate the emergence of accounts provided by autistic children in small-group discussions. Nine Finnish children (7–10 years old) attending school with special support participated in a five-month-duration pedagogical practice purposefully designed to enhance children’s participation in groups. We analyzed videos of sharing circles where children discussed their ideas and interests. Our data show three different account structures, which created different modes of children’s participation and gradually changed how they positioned themselves in the group. Results show how accounts can create different focuses of attention; reveal children’s reflections on what is relevant to them, and how to promote the exchange of ideas within a small group. Implications for the development of educational practices are discussed.
Model predictive control for path tracking in cable driven parallel robots with flexible cables: collocated vs. noncollocated control
Authors: Bettega Jason , Piva Giulio , Richiedei Dario , Trevisani Alberto
Published: February 2023

This paper proposes a novel control scheme for precise path tracking control in cable driven parallel robots (CDPRs) with axially-flexible cables, with particular focus to the challenging case of cable suspended parallel robots (CSPRs). To handle model nonlinearities while ensuring small computational effort, a controller made by two sequential control actions is developed. The first term is a position-dependent, model predictive control (MPC) with embedded integrator to compute the optimal cable tensions ensuring accurate path tracking and fulfilling the feasibility constraints; bounds on the feasible tensions are also included. The second control term transforms the optimal tensions into the commanded motor torques, and hence currents, that are evaluated through the kinetostatic model of the electric motors used for winding and unwinding the cables. Control design is performed through the robot dynamics model, formulated with the assumption of rigid cables. Moreover, the proposed control strategy is presented in two different architectures, collocated control and noncollocated control. Flexibility is handled by penalizing large tension variations in the cost function adopted in the controller design, plus some hard constraints on the maximum tension derivatives. These features, together with the embedding of the integrator within the MPC formulation, ensure smooth control tensions that allow handling the axial flexibility of the cables, although it is not explicitly considered in the controller design.

To assess the performances of the proposed control algorithm, a kinematically-determined robot with a suspended, lumped end-effector is simulated by also adopting very flexible cables. Additionally, a simplified dynamic model of the electrical dynamics and the sensor quantization are included to provide a realistic representation of the real environments. The results, together with the fair comparison with a benchmark, corroborate the effectiveness of the proposed approach, its robustness, and its feasibility in real-time controllers due to the wise reduction of the computational effort.
Copper(II) coordination polymer based on l-arginine as a supramolecular hybrid inorganic–organic material: synthesis, structural, spectroscopic and magnetic properties
Authors: Musioł Karol , Janczak Jan , Helios Katarzyna , Witwicki Maciej , Fitta Magdalena , Pełka Robert , Wojciechowska Agnieszka
Published: February 2023

We report the synthesis and structural, spectroscopic and magnetic properties of new 1D coordination polymeric complex {[Cu(μ-l-Arg)2]SO4⋅1.5H2O}n (1) that contains asymmetric μ−O,O’ carboxylic bridge linking distorted square-pyramidal [Cu(μ-l-Arg)2]2+ coordination units. In 1D, the syn−anti−μ2−η1:η1zigzag polymer conformation, the adjacent Cu(II) ions are distanced by 5.707 Å, and the subsequent Cu∙∙∙Cu proximity in 1D-coordination chain equals 6.978 Å. Detailed interpretation of IR and Raman spectra of l-arginine and 1 was performed. The principal components of the g tensor determined from EPR experiments (gx = 2.059, gy = 2.075, gz = 2.228) indicate nearly axial symmetry of Cu(II) coordination sphere and correspond to the unpaired electron occupying the dx2–y2 orbital. The single broad band at 16,200 cm–1, characteristic of d−d transition, is assigned to the dominant dublet-dublet 2B1g(dx2–y2)→ 2Eg(dyz≈dxz) transition. Magnetic susceptibility measurements have revealed ferromagnetic coupling between the Cu(II) ions within the 1D-coordination chain, while the intermolecular coupling is antiferromagnetic.

Graphical Abstract
DEHP mediates drug resistance by metabolic reprogramming in colorectal cancer cells
Authors: Wu Yue , Lu Ruijie , Lin Yujie , Wang Jinjin , Lou Zijian , Zheng Xiaochun , Zhang Ling , Pan Ruolang , Lu Gang , Fang Qingxia
Published: February 2023

Long-term exposure to diethylhexyl phthalate (DEHP), an endocrine-disrupting chemical (EDCs) and plasticizer widely used in consumer products, has been reported to be significantly positively correlated with increased risks of different human diseases, including various cancers, while the potential effect of DEHP on colorectal cancer progression was little studied. In the present study, we showed that DEHP could trigger the metabolic reprogramming of colorectal cancer cells, promote cell growth and decrease fluorouracil (5-FU) sensitivity. Mechanistic studies indicated that DEHP could reduce glycolysis activity and increase oxidative phosphorylation (OXPHOS) in SW620 cells. In addition, in vivo experiments showed that DEHP promoted tumorigenic progression and decreased survival time in mice. Collectively, our findings suggest that DEHP may be a potent risk factor for colorectal cancer development.
The cerebellum is causally involved in episodic memory under aging
Authors: Almeida Jorge , Martins Ana R. , Amaral Lénia , Valério Daniela , Bukhari Qasim , Schu Guilherme , Nogueira Joana , Spínola Mónica , Soleimani Ghazaleh , Fernandes Filipe , Silva Ana R. , Fregni Felipe , Simis Marcel , Simões Mário , Peres André
Published: February 2023

Episodic memory decline is a major signature of both normal and pathological aging. Many neural regions have been implicated in the processes subserving both episodic memory and typical aging decline. Here, we demonstrate that the cerebellum is causally involved episodic memory under aging. We show that a 12-day neurostimulation program delivered to the right cerebellum led to improvements in episodic memory performance under healthy aging that long outlast the stimulation period — healthy elderly individuals show episodic memory improvement both immediately after the intervention program and in a 4-month follow-up. These results demonstrate the causal relevance of the cerebellum in processes associated with long-term episodic memory, potentially highlighting its role in regulating and maintaining cognitive processing. Moreover, they point to the importance of non-pharmacological interventions that prevent or diminish cognitive decline in healthy aging.
Digital competence for emergency remote teaching in higher education: understanding the present and anticipating the future
Authors: Cook Henry , Apps Tiffani , Beckman Karley , Bennett Sue
Published: February 2023

Higher education has increasingly adopted online and blended models of teaching. Guided by institutional policy and digital competence frameworks, the integration of digital tools and competences is perceived as essential. The pivot to emergency remote teaching (ERT) in response to the COVID-19 pandemic increased the use of digital technologies and the need to deploy and support digital competences. Researchers captured a range of remote teaching practices in higher education across this period that highlight the adaptability of teachers despite a lack of preparation for such an event. This study reviewed empirical studies of ERT from the past 2 years to derive a conceptual frame for ERT digital competence, which was then applied as a lens to analyse teaching or digital competency frameworks from Australian universities. The findings of this paper demonstrate the pre-pandemic teaching and digital competency frameworks captured digital competencies relevant to ERT in varied ways. Practically, the findings provide a starting point for understanding digital competences needed for ERT to ensure future preparedness in responding to a crisis that disrupts educational provision. We also suggest universities can better support the development of teachers’ digital competence through practical operationalisations that connect technical and pedagogical knowledge, make digital possibilities across modes of delivery explicit, and acknowledge the need to protect wellbeing of educators.
Invisible borders in educational technology research? A comparative analysis
Authors: Marín Victoria I. , Buntins Katja , Bedenlier Svenja , Bond Melissa
Published: February 2023

Educational research is reflective of the nature and structure of national and regional education systems and their historical evolution. Educational technology research, as an area within educational research, reflects this case particularly prominently. Although individual countries and regions have varying research traditions, the publication of research in English as the scientific lingua franca can lead to missing nuances in terminology, which is often not reflected upon. Despite this, the exploration of research from different countries can still uncover diverse topical clusters. This study aims to identify the research topics in educational technology research in three countries (Germany, Spain and the United Kingdom), each with their own research traditions, through the terms used. To this end, a bibliometric analysis of 3034 article abstracts and keywords from 29 English-language Web of Science journals in the field of education and educational research was conducted, with a focus on educational technology. In addition, the quantitative findings are comparatively analysed by considering the corresponding cultural clusters. Main findings include diverse research foci in the three countries, also showing that distinct research traditions are still present, despite using English as lingua franca. Therefore, research articles written in English by non-English authors often do not reflect the same meanings in each country, despite using the same words. The conclusions reflect upon the need to establish ways of understanding the traditions behind those research articles and build collaborative systems to illustrate nuances in this research.
The Relationships Between Suicidal Ideation, Meaning in Life, and Affect: a Network Analysis
Authors: Guo Zhihua , Yang Tianqi , He Yang , Tian Wenqing , Wang Chaoxian , Zhang Yinling , Liu Jianjun , Liu Xufeng , Zhu Xia , Wu Shengjun
Published: February 2023

Transitioning from
holistic analysis to a fine-grained level analysis may provide further understanding of psychopathology. This study aimed to explore dimension-level relationships between suicidal ideation, meaning in life, and affect in a joint framework using network analysis and to identify potential prevention and intervention targets to address suicidal ideation. A total of 852 healthy adults aged 18–35 years completed self-report scales to assess suicidal ideation, meaning in life, and affect. A regularized partial correlation network was then built to examine the links between these dimensions. Expected influence and bridge expected influence values were calculated for each node. The prevalence of suicidal ideation was 4.2%. The search for and presence of meaning in life and positive and negative affect exhibited distinct and complex links to the three dimensions of suicidal ideation (pessimism, sleep, and despair). The important central nodes were search for meaning in life, sleep, despair, and positive affect, while the critical bridge nodes were positive affect, negative affect, and presence of meaning in life. These findings provide further understanding of the specific roles of meaning in life and affect in suicidal ideation. The identified nodes may be promising targets for prevention and intervention for suicidal ideation.
Surgical management of liver metastasis from colorectal cancer
Authors: Tschoegl Madita-Magdalena , Gruenberger Thomas
Published: February 2023

This short review illustrates the benefits of a multidisciplinary team approach, especially when it comes to the treatment of patients with colorectal cancer liver metastasis. Therefore, the classification to resectable and primarily unresectable disease has to be determined prior to the first treatment decision. Particularly the use of conversion chemotherapy has the potential of altering initially unresectable liver metastasis to a potentially resectable disease. The three possible therapy choices for synchronously metastasized colorectal cancer will be reflected in this review, as well as local therapeutic alternatives or combinations.
Personal adornments in West-Central Africa—the case study of a talc bead from the Kongo Kingdom (Mbanza Kongo, Angola)
Authors: Costa Mafalda , Barrulas Pedro , Lopes Maria da Conceição , Barreira João , de Jesus Maria da Piedade , da Silva Domingos Sónia , Vandenabeele Peter , Mirão José
Published: February 2023

A mustard-gold-colored talc bead was recovered during the 2014 excavation campaign carried out in Lumbu (Mbanza Kongo, Angola) together with the nineteenth-century glass trade beads imported from Bohemia and Venice. Results from this multi-analytical and minimally invasive study suggest that this bead may have been brought to the kingdom’s capital by means of an established intra-kingdom trade network or as an offering intended for the king or a member of the nobility. However, it was undoubtedly manufactured within the Kongo kingdom using talc sources known by the local population. As such, this talc bead constitutes the first evidence of local production of personal adornment objects in the Kongo kingdom and one of the first examples of craft specialization for personal adornment purposes in central and southern Africa since pre-historic times.
Breaking the Habit? Identifying Discrete Dimensions of Sitting Automaticity and Their Responsiveness to a Sitting-Reduction Intervention
Authors: Gardner Benjamin , Mainsbridge Casey P. , Rebar Amanda L. , Cooley P. Dean , Honan Cynthia , O’Brien Jane , Pedersen Scott J.
Published: February 2023

Background

Growing evidence suggests that sitting is activated automatically on exposure to associated environments, yet no study has yet sought to identify in what ways sitting may be automatic.

Method

This study used data from a 12-month sitting-reduction intervention trial to explore discrete dimensions of sitting automaticity, and how these dimensions may be affected by an intervention. One hundred ninety-four office workers reported sitting automaticity at baseline, and 3 months, 6 months, 9 months and 12 months after receiving one of two sitting-reduction intervention variants.

Results

Principal component analysis extracted two automaticity components, corresponding to a lack of awareness and a lack of control. Scores on both automaticity scales decreased over time post-intervention, indicating that sitting became more mindful, though lack of awareness scores were consistently higher than lack of control scores.

Conclusion

Attempts to break office workers’ sitting habits should seek to enhance conscious awareness of alternatives to sitting and afford office workers a greater sense of control over whether they sit or stand.
The Effects of a Mindfulness-Based Training in an Elementary School in Germany
Authors: Portele Christiane , Jansen Petra
Published: February 2023

Objectives

The primary goal of this study was to investigate the influence of the Mindfulness Education Workbook, a 6-week mindfulness-based tool, on emotion regulation, inhibition, physical self-concept, resources, and connectedness to nature. Furthermore, we explored whether a difference in number of hours of mindfulness practice would affect the outcomes.

Method

Ninety-one children from a public elementary school (M age = 9.74 years, SD = 0.76) participated in the study and were divided into three groups according to their respective school classes. The intervention group was divided into two groups that varied by number of hours of mindfulness practice: (a) mindfulness-plus and (b) mindfulness. In addition to biweekly training, the mindfulness-plus group also repeated a daily exercise. The passive control group received the standard school day instruction. The five concepts of emotion regulation, inhibition, physical self-concept, resources, and connectedness to nature were measured before and after the mindfulness intervention.

Results

For the measurement of emotion regulation, there was a significant effect in favor of the two mindfulness groups compared with the control group for the adaptive strategies in total as well as for their comprising emotions, anger, fear, and sadness, separately. Solely for the subscale mood elevation, the mindfulness-plus group showed significantly higher scores compared to the control group. Both mindfulness-plus and mindfulness groups varied from the control group on the measure of emotion regulation strategies, however not on the other four domains that were assessed (self-reports of resources, physical self-concept, and connectedness to nature as well as a mental task assessing inhibition). There was no evidence that the additional practice in the mindfulness-plus group significantly added to the intervention’s effectiveness.

Conclusions

The Mindfulness Education Workbook is a promising tool for elementary schools. Follow-up studies may provide further insights into the various effects of offering mindfulness training in schools. Further research with objective markers may also allow individual aspects under the umbrella term mindfulness to be investigated in more detail.

Preregistration

This study was not preregistered.
A reverse transcription loop-mediated isothermal amplification assay for the detection of citrus exocortis viroid in Australian citrus
Authors: Chambers Grant A , Geering Andrew DW , Holford Paul , Kehoe Monica A , Vidalakis Georgios , Donovan Nerida J
Published: February 2023

Citrus exocortis viroid (CEVd), the causal agent of exocortis, is a pathogen that is thought to infect all citrus varieties, although it is asymptomatic in most. Symptoms of exocortis develop on susceptible rootstocks, resulting in stunting and yield reduction. To aid the detection and management of CEVd, a rapid near-field assay was developed using reverse transcription loop-mediated isothermal amplification (RT-LAMP) for the detection of the viroids in nursery and field trees. Over 240 CEVd sequences, including sequence variants from representative Australian isolates that induce mild and severe symptoms, were used in the design of the primers. The RT-LAMP successfully detected CEVd in a 1:1000 dilution (236 pg) of plant total RNA indicating high sensitivity, and also detected the viroid in rapid, crude plant extractions. The assay was highly specific to CEVd, given there was no cross-reactivity with other citrus-infecting pathogens. This new assay provides a simple, robust, specific, and sensitive method to detect CEVd in Australian citrus and to our knowledge, is the first RT-LAMP assay to detect any citrus-infecting viroid.
MicroRNA expression profiling of RAS-mutant thyroid tumors with follicular architecture: microRNA signatures to discriminate benign from malignant lesions
Authors: Macerola E. , Poma A. M. , Vignali P. , Proietti A. , Torregrossa L. , Ugolini C. , Basolo A. , Matrone A. , Elisei R. , Santini F. , Basolo F.
Published: February 2023

Purpose

RAS mutations represent common driver alterations in thyroid cancer. They can be found in benign, low-risk and malignant thyroid tumors with follicular architecture, which are often diagnosed as indeterminate nodules on preoperative cytology. Therefore, the detection of RAS mutations in preoperative setting has a suboptimal predictive value for malignancy. In this study, we investigated differentially expressed microRNA (miRNA) in benign and malignant thyroid tumors with follicular architecture carrying mutations in RAS genes.

Methods

Total RNA was purified from 60 RAS-mutant follicular-patterned thyroid tumors, including follicular adenoma (FA), noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), papillary and follicular thyroid carcinoma cases (PTC, FTC); 22 RAS-negative FAs were used as controls. The expression analysis of 798 miRNAs was performed by digital counting (nCounter nanoString platform).

Results

Comparing RAS-mutant and RAS-negative FAs, 12 miRNAs showed significant deregulation, which was likely related to the oncogenic effects of RAS mutations. Twenty-two miRNAs were differentially expressed in RAS-mutant benign versus malignant tumors. Considering the tumor type, 24 miRNAs were deregulated in PTC, 19 in NIFTP, and seven in FTC and compared to FA group; among these, miR-146b-5p, miR-144-3p, and miR-451a showed consistent deregulation in all the comparisons with the highest fold change.

Conclusions

The miRNA expression analysis of follicular-patterned thyroid tumors demonstrated that RAS mutations influences miRNA profile in benign tumors. In addition, several miRNAs showed a histotype-specific deregulation and could discriminate between RAS-mutant benign and RAS-mutant malignant thyroid lesions, thus deserving further investigation as potential diagnostic markers.
How do students use their ethical compasses during internship? An empirical study among students of universities of applied sciences
Authors: Van Stekelenburg Lieke , Smerecnik Chris , Sanderse Wouter , de Ruyter Doret J.
Published: February 2023

The aim of this empirical study is to understand how bachelor students at universities of applied sciences (UAS) use their ethical compasses during internships. Semi-structured interviews were held with 36 fourth-year bachelor students across four UAS and three different programs in the Netherlands: Initial Teacher Education, Business Services, and Information and Communication Technology. To our knowledge, no studies appear to have investigated and compared students from multiple professional fields, nor identified the dynamics and the sequence of the strategies in the decision-making process that students use when faced with ethical dilemmas during internships. We found that students’ ethical dilemmas stemmed from: mentors’ or managers’ behaviours/requests, colleagues’ behaviours, organisations’ morally questionable incentives, pupils’ home situations, and pupils’ behaviours/personal stories. The majority of students used multiple strategies and first investigated the ethical dilemmas they encountered and then avoided, intervened, delegated responsibilities, or adjusted to their environments. Students’ values played an important role in experiencing an ethical dilemma, however, these values were not always acted upon. We identified that rather students’ beliefs about having influence and/or ownership (or not), personal interest(s) and power relations influenced the way how they used their ethical compasses. Thus, instead of navigating on moral standards (of their profession), students reacted on beliefs which reflected the ways in which they constructed their internship contexts, social relationships and their own (and others) needs. As a result, half of the mentioned dilemmas were resolved in a prudent-strategic manner (e.g., by prioritising personal interests), instead of morally. This indicates that students did not always convert (moral) values into moral action and did not use their ethical compasses in the way UAS aspires. Finally, this study found that the ways in which students used their ethical compasses were strongly influenced by their environments.
High-precision controller using LMI method for three-axis flexible satellite attitude stabilisation
Authors: Eddine B.J. , Boulanouar K. , Elhassen B.
Published: February 2023

This paper considers the problem of a three-axis flexible satellite attitude stabilisation subject to the vibration of flexible appendages and external environmental disturbances, which affect the rigid body motion. To solve this problem, a disturbance observer is proposed to estimate and thereby reject the flexible appendage vibration. Based on the H∞ and Linear Matrix Inequality (LMI) approach, a controller for spacecraft with flexible appendages is proposed to ensure robustness as well as attitude stability with high precision. Stability analysis of the overall closed-loop system is provided via the Lyapunov method. The simulation results of three-axis flexible spacecraft demonstrate the robustness and effectiveness of the proposed method.
Engines of power: Electricity, AI, and general-purpose, military transformations
Authors: Ding Jeffrey , Dafoe Allan
Published: February 2023

Major theories of military innovation focus on relatively narrow technological developments, such as nuclear weapons or aircraft carriers. Arguably the most profound military implications of technological change, however, come from more fundamental advances arising from ‘general-purpose technologies’ (GPTs), such as the steam engine, electricity, and the computer. Building from scholarship on GPTs and economic growth, we argue that the effects of GPTs on military effectiveness are broad, delayed, and shaped by indirect productivity spillovers. We label this impact pathway a ‘general-purpose military transformation’ (GMT). Contrary to studies that predict GPTs will rapidly diffuse to militaries around the world and narrow gaps in capabilities, we show that GMTs can reinforce existing balances if leading militaries have stronger linkages to a robust industrial base in the GPT than challengers. Evidence from electricity's impact on military affairs, covering the late nineteenth and early twentieth centuries, supports our propositions about GMTs. To probe the explanatory value of our theory and account for alternative interpretations, we compare findings from the electricity case to the military impacts of submarine technology, a non-GPT that emerged in the same period. Finally, we apply our findings to contemporary debates about artificial intelligence, which could plausibly cause a profound GMT.
Scalable interventions for refugees
Authors: Bryant Richard A.
Published: February 2023

Refugees experience a greater rate of common mental disorders relative to most other populations, and there remains a need to address these needs. However, most refugees are hosted in low-and-middle-income countries, where there is a lack of resources and mental health providers who can deliver mainstream mental health services. This situation has led to the emergence of scalable mental health interventions that can deliver evidence-based programs to refugees in need. Many countries hosting refugees have implemented programs that train local lay providers in interventions that can be delivered at scale. This review provides a narrative overview of these scalable interventions and critiques the evidence for their efficacy. It is noted that there are limitations to currently available scalable interventions, and there is a need for greater attention to determining the longer-term benefits of interventions, addressing the mental health needs of refugees who do not respond to these interventions, assisting refugees with more severe psychological disorders, and understanding the specific mechanisms that underpin observed benefits of these interventions.
A non-local spectral transfer model and new scaling law for scalar turbulence
Authors: Akhavan-Safaei Ali , Zayernouri Mohsen
Published: February 2023

In this study, we revisit the spectral transfer model for the turbulent intensity in passive scalar transport (under large-scale anisotropic forcing), and a subsequent modification to the scaling of scalar variance cascade is presented. From the modified spectral transfer model, we obtain a revised scalar transport model using a fractional-order Laplacian operator that facilitates the robust inclusion of the non-local effects originating from large-scale anisotropy transferred across the multitude of scales in the turbulent cascade. We provide an a priori estimate for the non-local model based on the scaling analysis of the scalar spectrum, and later examine our developed model through direct numerical simulation. We present a detailed analysis on the evolution of the scalar variance, high-order statistics of the scalar gradient and important two-point statistical metrics of the turbulent transport to make a comprehensive comparison between the non-local model and its standard version. Finally, we present an analysis that seamlessly reconciles the similarities between the developed model with the fractional-order subgrid-scale scalar flux model for large-eddy simulation (Akhavan-Safaei et al., J. Comput. Phys., vol. 446, 2021, 110571) when the filter scale approaches the dissipative scales of turbulent transport. In order to perform this task, we employ a Gaussian process regression model to predict the model coefficient for the fractional-order subgrid model.
On Tournaments and negative dependence
Authors: Malinovsky Yaakov , Rinott Yosef
Published: February 2023

Negative dependence of sequences of random variables is often an interesting characteristic of their distribution, as well as a useful tool for studying various asymptotic results, including central limit theorems, Poisson approximations, the rate of increase of the maximum, and more. In the study of probability models of tournaments, negative dependence of participants’ outcomes arises naturally, with application to various asymptotic results. In particular, the property ofnegative orthant dependencewas proved in several articles for different tournament models, with a special proof for each model. In this note we unify these results by proving a stronger property,negative association, a generalization leading to a very simple proof. We also present a natural example of a knockout tournament where the scores are negatively orthant dependent but not negatively associated. The proof requires a new result on a preservation property of negative orthant dependence that is of independent interest.
An improved method for isolating camallanid (Nematoda) spicules for scanning electron microscopy
Authors: Nofal A.P. , Dos Santos Q.M. , Avenant-Oldewage A.
Published: February 2023

In nematodes, the structure of male copulatory organs is a significant taxonomic distinguisher and includes the morphometry of the spicules. The description of these structures mainly relies on the study of whole mounts using light microscopy. In rare instances, protruding spicules have been described with scanning electron microscopy. Even fewer studies have described the ultrastructure of isolated spicules following their isolation. In the present study, two different methods of spicule isolation were performed on two parasitic camallanid nematodes, Procamallanus (Procamallanus) pseudolaeviconchus Moravec & van As, 2015 and Paracamallanus cyathopharynx (Baylis, 1923), from African sharptooth catfish to determine the practicality and efficiency of the methodologies. The first method involved using sharpened tungsten needles and microdissection of the spicule pouch to free the spicules, followed by soft tissue digestion if necessary. Alternatively, the spicules were isolated through mechanical release instead of dissection in a method developed in the current study. This involved freeing the spicules from surrounding soft tissue by placing live specimens between a coverslip and a glass slide in a drop of water and exerting pressure with small rotational movements. Both methods yielded favourable results, but Method 2 is recommended for future studies due to the many advantages.
THE MISSING LOGIC: TRACES OF A LOST BOOK ON HYPOTHETICAL SYLLOGISTIC IN AVICENNA'S RISĀLA MŪǦAZA FĪ UṢŪL AL-MANṬIQ
Authors: Di Vincenzo Silvia
Published: February 2023

Do Avicenna’s extant works preserve any trace of his now-lost early philosophical production? This paper considers a hitherto neglected text, namely the chapter “On Hypothetical Propositions” from Avicenna’s “Concise Treatise on the Principles of Logic” (Risāla mūǧaza fī uṣūl al-manṭiq, henceforth: RM). The new evidence offered by the RM chapter in question will lead to a different reading of another well-known passage of Avicenna’s reworking of Aristotle’s Prior Analytics (Qiyās) from the “Book of Healing” (Kitāb al-šifāʾ). The clues gathered from an analysis of these two works will finally lead us to ponder the possibility that Avicenna may in fact have composed a (now lost) work on hypothetical propositions and syllogisms. Since Avicenna’s RM is to date unedited, an edition, as well as an English translation of the relevant chapter, is also provided in the Appendix of this paper.
The “Vanishing Indian” and the Vanishing Pole: From a Middle Ground to a Logic of Elimination in the European and Global Periphery, 1840–1880
Authors: Patton Raymond A.
Published: February 2023

This article examines the use of the “Vanishing Indian” and “Doomed Race” extinction narratives in the writings of Henryk Sienkiewicz, Paul Edmund Strzelecki, and Sygurd Wiśniowski with respect to the Indigenous peoples of North America, Australia, and New Zealand. It locates these writers in the context of mid-late nineteenth century Poland, at the periphery of Europe and of empire, arguing that they demonstrated an ability to detect and critique the injustices of colonialism and sought out a rhetorical “middle ground” between Poles and non-European victims of empire in their work. However, their sympathy was in tension with Poland's historic role as a regional metropole, the need to assert their status as White Europeans, and the lure of settler colonialism. The “middle ground” they sought to create ultimately gave way to a “logic of elimination” that neutralized this tension, justifying colonialism to themselves and to other agents of empire.
The Silence of the Occupied in Czech Literature, 1940–46
Authors: Chitnis Rajendra A.
Published: February 2023

The use of silence to characterize the dominant response of occupied populations during the Second World War recurs throughout post-war European literature and is especially prominent in Czech writing. Interpreting the meaning of this silence therefore became central to Czech efforts to establish a preferred narrative about the German occupation in the immediate post-war period. Through analysis of the motif in more and less well-known works published between 1940 and 1946, I shall map the narrowing understanding of the silence of the occupied from its varied, ambiguous portrayal in the now forgotten first Czech novel about the Occupation, Silences by Josef Horal, to its unequivocal interpretation as resistance in Jan Drda's canonical The Mute Barricade. While this narrowing reflects Tony Judt's notion of a “collective amnesia” necessary for national unity and recovery, the marginalization of certain perspectives also presages the broader move in Czech post-war society away from pluralism to nationalist authoritarianism.