bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of energy extraction of PV systems affected by environmental factors under real outdoor conditions
Authors: Hassan Muhammed A. , Bailek Nadjem , Bouchouicha Kada , Ibrahim Abdelhameed , Jamil Basharat , Kuriqi Alban , Nwokolo Samuel Chukwujindu , El-kenawy El-Sayed M.
Published: August 2022

The global agenda to increase the renewable energy share has driven many countries and entities to harness solar energy from solar photovoltaic (PV) systems. However, the power generation of PV systems is strongly affected by climate conditions. Therefore, the main objective of this study is to analyze and predict the power generation of different PV technologies under arid desert climate conditions on an hourly basis. Two areas have been considered as case studies: Adrar in Algeria and Alice Springs in Australia. A total of nine physical models and input parameter combinations from six different power plants have been used and tested for the suitability of the proposed models for predicting the power yield of PV power plants depending on solar irradiance and other meteorological variables. Then, an ensemble learning technique is applied to improve the performance capabilities of the best-fit input combinations. The results reveal that the global irradiance, ambient air temperature, and relative humidity combination are the most related to the PV power output of all technologies under all-sky conditions and provide effective and efficient performance with the proposed ensemble learning, with an estimated accuracy of over 99%.
Entwicklung einer thorakoabdominellen Hybridprothese – vom Konzept zur Erstimplantation
Authors: Wipper Sabine , Kölbel Tilo , Enzmann Florian , Debus Eike Sebastian
Published: August 2022

Hintergrund

Die Therapie thorakoabdomineller Aortenpathologien ist nach wie vor eine Herausforderung, sowohl endovaskulär als auch offen-chirurgisch.

Fragestellung

Ziel war die Entwicklung einer Hybridprothese zur Versorgung der thorakoabdominellen Aorta ohne Thorakotomie, thorakale Artenklemmung und Herz-Lungen-Maschine (HLM).

Material und Methode

Nach Testung am Modell wurde die Implantationstechnik und Handhabung der neuen Hybridprothese in-vivo im Großtiermodell nach standardisiertem Protokoll evaluiert. Auch Operationsdauer, Hämodynamik und Organperfusion inklusive spinaler Perfusion wurden mittels Fluoreszenzmikrosphärentechnik untersucht. Die Ergebnisse wurden mit einer konventionellen offen-chirurgischen Versorgung verglichen. Bildgebende Erfolgskontrollen erfolgten mittels Angiographie und postmortaler CT-Angiographie. Basierend auf den Ergebnissen erfolgte die Modifikation des Prototyps und der Operationstechnik, bevor die erste Implantation am Patienten erfolgte.

Ergebnisse

Im Rahmen der In-vivo-Evaluation wurde der Graft in mehreren Schritten modifiziert, um die Implantationstechnik möglichst einfach und sicher zu gestalten. Das finale Design der neu entwickelten Thoracoflo®-Hybridprothese (Terumo Aortic, Vascutek Ltd. Scotland, UK) beinhaltet einen proximalen Stentgraft, der über eine Halsmanschette mit einer 7‑fach gebranchten abdominellen Dacron-Prothese verbunden ist. Die retrograde viszerale Perfusion über eine temporär angelegte End-zu-Seit-Anastomose eines Iliakalschenkels mit einer Iliakalarterie nach Implantation des thorakalen Stentgraft-Anteils (SPIDER-Technik) ermöglicht eine Operation ohne Thorakotomie und HLM. Die Thoracoflo®-Hybridprothese konnte erfolgreich an einer selektionierten Patientin implantiert werden.

Schlussfolgerung

Nach ausführlicher In-vitro- und In-vivo-Testung konnte ein neues Hybridverfahren mit der Thoracoflo®-Hybridprothese entwickelt werden, das bereits erfolgreich an einer Patientin eingesetzt wurde.
Usefulness of ultrasonography and elastography in diagnosing oxaliplatin-induced sinusoidal obstruction syndrome
Authors: Saito Rika , Kawamoto Yasuyuki , Nishida Mutsumi , Iwai Takahito , Kikuchi Yasuka , Yokota Isao , Takagi Ryo , Yamamura Takahiro , Ito Ken , Harada Kazuaki , Yuki Satoshi , Komatsu Yoshito , Sakamoto Naoya
Published: August 2022

Background

Sinusoidal obstruction syndrome (SOS) refers to liver injury caused by hematopoietic stem cell transplantation (HSCT) and anticancer drugs including oxaliplatin. Increased splenic volume (SV) on computed tomography (CT) indicates oxaliplatin-induced SOS. Similarly, ultrasonography and liver stiffness measurement (LSM) by shear-wave elastography (SWE) can help diagnose SOS after HSCT; however, their usefulness for diagnosing oxaliplatin-induced SOS remains unclear. We investigated the usefulness of the Hokkaido ultrasonography-based scoring system with 10 ultrasonographic parameters (HokUS-10) and SWE in diagnosing oxaliplatin-induced SOS early.

Methods

In this prospective observational study, ultrasonography and SWE were performed before and at 2, 4, and 6 months after oxaliplatin-based chemotherapy. HokUS-10 was used for assessment. CT volumetry of the SV was performed in clinical practice, and an SV increase ≥ 30% was considered the diagnostic indicator of oxaliplatin-induced SOS. We assessed whether HokUS-10 and SWE can lead to an early detection of oxaliplatin-induced SOS before an increased SV on CT.

Results

Of the 30 enrolled patients with gastrointestinal cancers, 12 (40.0%) with an SV increase  ≥ 30% on CT were diagnosed with SOS. The HokUS-10 score was not correlated with an SV increase ≥ 30% (r = 0.18). The change in rate of three HokUS-10 parameters were correlated with an SV increase ≥ 30% (r = 0.32–0.41). The change in rate of LSM by SWE was correlated with an SV increase  ≥ 30% (r = 0.40).

Conclusions

The usefulness of HokUS-10 score was not demonstrated; however, some HokUS-10 parameters and SWE could be useful for the early diagnosis of oxaliplatin-induced SOS.
Automated Protocoling for MRI Exams—Challenges and Solutions
Authors: Denck Jonas , Haas Oliver , Guehring Jens , Maier Andreas , Rothgang Eva
Published: August 2022

Automated protocoling for MRI examinations is an amendable target for workflow automation with artificial intelligence. However, there are still challenges to overcome for a successful and robust approach. These challenges are outlined and analyzed in this work. Through a literature review, we analyzed limitations of currently published approaches for automated protocoling. Then, we assessed these limitations quantitatively based on data from a private radiology practice. For this, we assessed the information content provided by the clinical indication by computing the overlap coefficients for the sets of ICD-10-coded admitting diagnoses of different MRI protocols. Additionally, we assessed the heterogeneity of protocol trees from three different MRI scanners based on the overlap coefficient, on MRI protocol and sequence level. Additionally, we applied sequence name standardization to demonstrate its effect on the heterogeneity assessment, i.e., the overlap coefficient, of different protocol trees. The overlap coefficient for the set of ICD-10-coded admitting diagnoses for different protocols ranges from 0.14 to 0.56 for brain/head MRI exams and 0.04 to 0.57 for spine exams. The overlap coefficient across the set of sequences used at two different scanners increases when applying sequence name standardization (from 0.81/0.86 to 0.93). Automated protocoling for MRI examinations has the potential to reduce the workload for radiologists. However, an automated protocoling approach cannot be solely based on admitting diagnosis as it does not provide sufficient information. Moreover, sequence name standardization increases the overlap coefficient across the set of sequences used at different scanners and therefore facilitates transfer learning.
Soil carbon sequestration as a climate strategy: what do farmers think?
Authors: Buck Holly Jean , Palumbo-Compton Alexis
Published: August 2022

Countries and companies with net-zero emissions targets are considering carbon removal strategies to compensate for remaining greenhouse gas emissions. Soil carbon sequestration is one such carbon removal strategy, and policy and corporate interest is growing in figuring out how to motivate farmers to sequester more carbon. But how do farmers in various cultural and geographic contexts view soil carbon sequestration as a climate mitigation or carbon removal strategy? This article systematically reviews the empirical social science literature on farmer adoption of soil carbon sequestration practices and participation in carbon markets or programs. The article finds thirty-seven studies over the past decade that involve empirical research with soil carbon sequestering practices in a climate context, with just over a quarter of those focusing on the Global South. A central finding is co-benefits are a strong motivator for adoption, especially given minimal carbon policies and low carbon prices. Other themes in the literature include educational and cultural barriers to adoption, the difference between developing and developed world contexts, and policy preferences among farmers for soil carbon sequestration incentives. However, we argue that given the rising profile of technical potentials and carbon credits, this peer-reviewed literature on the social aspects of scaling soil carbon sequestration is quite limited. We discuss why the social science literature is so small, and what this research gap means for efforts to achieve higher levels of soil carbon sequestration. We conclude with a ten-point social science research agenda for social science on soil carbon—and some cautions about centering carbon too strongly in research and policy.
Postmenopausal overweight and breast cancer risk; results from the KARMA cohort
Authors: Klintman Marie , Rosendahl Ann H. , Randeris Benjamin , Eriksson Mikael , Czene Kamila , Hall Per , Borgquist Signe
Published: August 2022

Purpose

To study the risk of incident breast cancer and subtype-specific breast cancer in relation to excess body weight in a contemporary Swedish prospective cohort study, The Karolinska Mammography Project for Risk Prediction of Breast Cancer, KARMA.

Methods

A total of 35,412 postmenopausal women attending mammography and included in the KARMA study provided baseline data on body mass index (BMI) and potential confounders. During eight years of follow-up, 822 incident invasive breast cancer cases were identified.

Results

Women with overweight (BMI ≥ 25–< 30 kg/m2) constituting 34% of the study cohort had an increased risk of incident breast cancer with an adjusted Hazard Ratio (HRadj) 1.19 (95% CI 1.01–1.4). A similar, however, non-significant, association was found for women with obesity (BMI ≥ 30 kg/m2) conferring 13% of the cohort, with a HRadj of 1.19 (95% CI 0.94–1.5). Overweight was associated with risk of node-negative disease (HRadj 1.29, 95% CI 1.06–1.58), whereas obesity was associated with node-positive disease (HRadj 1.64, 95% CI 1.09–2.48). Both overweight and obesity were associated with risk of estrogen receptor positive (ER+) disease (HRadj 1.20, 95% CI 1.00–1.44 and HRadj 1.33, 95% CI 1.03–1.71, respectively), and low-grade tumors (HRadj 1.25, 95% CI 1.02–1.54, and HRadj 1.40, 95% CI 1.05–1.86, respectively). Finally, obesity was associated with ER+HER2 negative disease (HRadj 1.37, 95% CI 1.05–1.78) and similarly luminal A tumors (HRadj 1.43, 95% CI 1.02–2.01).

Conclusion

Overweight and obesity are associated with an increased risk of developing breast cancer, specifically ER+, low-grade, and for obesity, node-positive, high-risk breast cancer indicating a further need for risk communication and preventive programs.
Obesity: a perfect storm for carcinogenesis
Authors: Harris Benjamin H. L. , Macaulay Valentine M. , Harris David A. , Klenerman Paul , Karpe Fredrik , Lord Simon R. , Harris Adrian L. , Buffa Francesca M.
Published: August 2022

Obesity-related cancers account for 40% of the cancer cases observed in the USA and obesity is overtaking smoking as the most widespread modifiable risk factor for carcinogenesis. Here, we use the hallmarks of cancer framework to delineate how obesity might influence the carcinogenic hallmarks in somatic cells. We discuss the effects of obesity on (a) sustaining proliferative signaling; (b) evading growth suppressors; (c) resisting cell death; (d) enabling replicative immortality; (e) inducing angiogenesis; (f) activating invasion and metastasis; (g) reprogramming energy metabolism; and (h) avoiding immune destruction, together with its effects on genome instability and tumour-promoting inflammation. We present the current understanding and controversies in this evolving field, and highlight some areas in need of further cross-disciplinary focus. For instance, the relative importance of the many potentially causative obesity-related factors is unclear for each type of malignancy. Even within a single tumour type, it is currently unknown whether one obesity-related factor consistently plays a predominant role, or if this varies between patients or, even in a single patient with time. Clarifying how the hallmarks are affected by obesity may lead to novel prevention and treatment strategies for the increasingly obese population.
A range-wide analysis of population structure and genomic variation within the critically endangered spiny daisy (Acanthocladium dockeri)
Authors: Brooks Elodie , Slender Amy L , Cu Suong , Breed Martin F , Stangoulis James CR
Published: August 2022

Understanding population structure and genetic diversity is important for designing effective conservation strategies. As a critically endangered shrub, the six remaining extant populations of spiny daisy (Acanthocladium dockeri) are restricted to country roadsides in the mid-north of South Australia, where the species faces many ongoing abiotic and biotic threats to survival. Currently the spiny daisy is managed by selecting individuals from the extant populations and translocating them to establish insurance populations. However, there is little information available on the genetic differentiation between populations and diversity within source populations, which are essential components of planning translocations. To help fill this knowledge gap, we analysed population structure within and among all six of its known wild populations using 7,742 SNPs generated by a genotyping-by-sequencing approach. Results indicated that each population was strongly differentiated, had low levels of genetic diversity, and there was no evidence of inter-population gene flow. Individuals within each population were generally closely related, however, the Melrose population consisted entirely of clones. Our results suggest genetic rescue should be applied to wild spiny daisy populations to increase genetic diversity that will subsequently lead to greater intra-population fitness and adaptability. As a starting point, we suggest focussing on improving seed viability via inter-population crosses such as through hand pollination experiments to experimentally assess their sexual compatibility with the hope of increasing spiny daisy sexual reproduction and long-term reproductive fitness.
My Wealth, (Y)Our Life Satisfaction? Sole and Joint Wealth Ownership and Life Satisfaction in Marriage
Authors: Kapelle Nicole , Nutz Theresa , Tisch Daria , Schechtl Manuel , Lersch Philipp M. , Struffolino Emanuela
Published: August 2022

This study examines the money-subjective well-being nexus by studying the link between changes in jointly and solely (i.e. respondents’ own and their partner’s own) held gross wealth and changes in married individuals’ subjective well-being. Joint assets reflect norms of sharing responsibilities and resources. Solely held assets, in contrast, offer individual economic independence. Using wealth data from the German Socio-Economic Panel Study (SOEP; 2002, 2007, 2012, 2017), we estimate individual fixed effects regressions. Although coefficients for all three wealth measures are positive, our results highlight that only increases in jointly held wealth are associated with statistically significant increases in spouses’ life satisfaction in Germany. Despite expectations about a stronger relevance of joint wealth for men compared to women in line with men’s role as a financial provider for the family, we do not find substantial gender differences in the positive association between increases in joint wealth and life satisfaction. In light of the individualisation of marriages, our results highlight that the personal benefits associated with marital sharing of wealth seem to trump those of economic independence and financial autonomy.
Satellite multispectral indices to estimate canopy parameters and within-field management zones in super-intensive almond orchards
Authors: Sandonís-Pozo L. , Llorens J. , Escolà A. , Arnó J. , Pascual M. , Martínez-Casasnovas J. A.
Published: August 2022

Continuous canopy status monitoring is an essential factor to support and precisely apply orchard management actions such as pruning, pesticide and foliar treatment applications, or fertirrigation, among others. For that, this work proposes the use of multispectral vegetation indices to estimate geometric and structural orchard parameters from remote sensing images (high temporal and spatial resolution) as an alternative to more time-consuming processing techniques, such as LiDAR surveys or UAV photogrammetry. A super-intensive almond (Prunus dulcis) orchard was scanned using a mobile terrestrial laser (LiDAR) in two different vegetative stages (after spring pruning and before harvesting). From the LiDAR point cloud, canopy orchard parameters, including maximum height and width, cross-sectional area and porosity, were summarized every 0.5 m along the rows and interpolated using block kriging to the pixel centroids of PlanetScope (3 × 3 m) and Sentinel-2 (10 × 10 m) image grids. To study the association between the LiDAR-derived parameters and 4 different vegetation indices. A canonical correlation analysis was carried out, showing the normalized difference vegetation index (NDVI) and the green normalized difference vegetation index (GNDVI) to have the best correlations. A cluster analysis was also performed. Results can be considered optimistic both for PlanetScope and Sentinel-2 images to delimit within-field management zones, being supported by significant differences in LiDAR-derived canopy parameters.
A Conceptual Model of Help-Seeking by Black Americans After Violent Injury: Implications for Reducing Inequities in Access to Care
Authors: Roman Caterina G.
Published: August 2022

Many inequities exist in serving and supporting Black survivors of violent crime. A key question in reducing inequities in care after victimization is whether police first responders and other formal system providers identify the victim as an “offender” and/or someone who is “undeserving” of supports. These labels and associated biases can directly reduce access to supports through a variety of mechanisms that include police withholding information about one’s rights as a victim, among other direct and indirect barriers to social and health services. Unaddressed financial, mental, and physical health consequences of victimization contribute to poorer health outcomes later in life. This paper seeks to bring together the extant research on help-seeking, discrimination in criminal legal system functioning, and barriers to victim services by synthesizing these discrete threads into a theoretically and empirically informed conceptual model that captures the range of factors that shape Black Americans’ decision to report their victimization to the police and subsequent help-seeking. Qualitative and quantitative data from a purposive sample of 91 Black victims of community violence is used to ground the developing model. The conceptual model can help lay the foundation for research that seeks to remedy the marked mismatch between the prevalence of violent victimization and help-seeking among Black Americans. Research findings can be applied to guide policies and programming to reduce inequities in care for victims of violence.
The Role of Stress Echocardiography in Valvular Heart Disease
Authors: Citro Rodolfo , Bursi Francesca , Bellino Michele , Picano Eugenio
Published: August 2022

Purpose of Review

Stress echocardiography is recommended in valvular heart disease when there is a mismatch between resting transthoracic echocardiography findings and symptoms during activities of daily living. We describe the current methodology and the evidence supporting these applications.

Recent Findings

The comprehensive stress echo assessment includes valve function (gradients and regurgitation), left ventricular global systolic and diastolic function, left atrial volume, pulmonary congestion, pulmonary arterial pressure, and right ventricular function, integrated with blood pressure response with cuff sphygmomanometer, chronotropic reserve with heart rate, and symptoms.

Recent guidelines recommend the evaluation of asymptomatic severe or symptomatic non-severe mitral regurgitation or stenosis with exercise stress and suspected low-flow, low-gradient severe aortic stenosis with reduced ejection fraction with low dose (up to 20 mcg, without atropine) dobutamine stress. Prospective, large-scale studies based on a comprehensive protocol (ABCDE +) capturing the multiplicity of clinical phenotypes are needed to support stress echo-driven treatment strategies.
Mechanismen des Proteinimports in das humane endoplasmatische Retikulum
Authors: Zimmermann Richard
Published: August 2022

In human cells, one third of all polypeptides enter the secretory pathway at the ER. This process involves N-terminal signal peptides or internal transmembrane helices in the precursors and one hundred cytosolic and ER proteins, which facilitate their ER import or processing. In the past fifty years four pathways for targeting of precursors to the Sec61 channel plus various allosteric channel effectors and supporting or stand alone membrane protein insertases were characterized by the field.
In vitro-Amplifikation humaner hämatopoetischer Stammzellen im 3D-System
Authors: Marx-Blümel Lisa , Marx Christian , Schober Andreas , Beck James F.
Published: August 2022

A promising strategy to increase the numbers of hematopoietic stem cells (HSCs) for clinical applications, like stem cell transplantation, is offered by advanced in vitro culture systems. We developed artificial 3D bone marrow-like scaffolds made of polydimethylsiloxane (PDMS) mimicking the natural HSC niche in vitro. These 3D PDMS scaffolds in combination with an optimized culture medium allow the amplification of high numbers of undifferentiated HSCs by activating specific molecular signaling pathways.
Stammzelltherapien für Muskeldystrophien
Authors: Fernandez Helena Escobar
Published: August 2022

Muscular dystrophies are devastating and untreatable genetic diseases leading to progressive muscle degeneration and weakness. The expanding landscape of CRISPR-Cas-based genome editing tools allows the in situ repair of many disease-causing mutations in patient cells in an unprecedented manner. Here, I discuss recent advances and challenges for using gene edited muscle stem cells in autologous cell replacement therapies to treat muscular dystrophy.
RNA-Polymerase I: einer spezialisierten Transkriptionsmaschine auf der Spur
Authors: Pilsl Michael , Tschochner Herbert , Griesenbeck Joachim , Engel Christoph
Published: August 2022

In eukaryotes three major nuclear RNA Polymerases (Pols I, II and III) transcribe the genome. Pols II and III transcribe many different genes. Pol I has only one target from which it synthesizes the precursor for 3 of 4 ribosomal (r)RNAs accounting for up to 60 percent of total cellular RNA. Dedication of Pol I and its specific transcription factors to transcribe a single gene underlines the importance of rRNA synthesis. Research in Regensburg aims at understanding mechanism(s) of Pol I transcription.
Mikrobielle Antibiotikafabriken verstehen und verbessern
Authors: Gressler Markus , Kries Hajo
Published: August 2022

Repurposing the enzymes in microbial metabolism such as nonribosomal peptide synthetases (NRPSs) is explored as a route towards better antibiotics. NRPSs are gigantic enzymatic assembly lines that form highly modified peptides from diverse building blocks. A novel hydroxamate assay detects full substrate profiles of NRPSs from cell-like substrate mixtures. Facile recording of substrate profiles has applications in natural product discovery and engineering.
Biomaterialien — Nachbildung der Stammzellnische in Bioreaktoren
Authors: Neubauer Julia C. , Gepp Michael M.
Published: August 2022

The generation of high-quality human pluripotent stem cells and their derivatives requires growth surfaces imitating the natural micro-environment. Stiff plastic surfaces with protein coatings are not an optimal stem cell niche and adjustable growth surfaces are needed to meet the cell-specific requirements. Alginate hydrogels are versatile biomaterials in stem cell processes since they can be integrated in all fundament cell workflows not only as planar surface but also as microcarrier cultures in suspension bioreactors.
Stammzellforschung an und mit Affen: zwischen Grundlagen und Anwendung
Authors: Behr Rüdiger
Published: August 2022

Pluripotent stem cells (PSC) are important for several areas of bio-medicine, including cell replacement therapy and embryonic development. Non-human primates (NHP) are of paramount importance as human models for translating cell replacement therapies into the clinic. However, this requires NHP-PSC that meet specific quality criteria. We have generated appropriate NHP-PSC. Our work contributes to making the NHP even more useful as a preclinical model in biomedical research.
Simulation of wheel and rail profile wear: a review of numerical models
Authors: Bosso N. , Magelli M. , Zampieri N.
Published: August 2022

The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile shapes. This work surveys the main numerical models in the literature for the evaluation of the uniform wear of wheel and rail profiles. The standard structure of these tools includes a multibody simulation of the wheel–track coupled dynamics and a wear module implementing an experimental wear law. Therefore, the models are classified according to the strategy adopted for the worn profile update, ranging from models performing a single computation to models based on an online communication between the dynamic and wear modules. Nevertheless, the most common strategy nowadays relies on an iteration of dynamic simulations in which the profiles are left unchanged, with co-simulation techniques often adopted to increase the computational performances. Work is still needed to improve the accuracy of the current models. New experimental campaigns should be carried out to obtain refined wear coefficients and models, while strategies for the evaluation of both longitudinal and transversal wear, also considering the effects of tread braking, should be implemented to obtain accurate damage models.
Graph neural networks for multivariate time series regression with application to seismic data
Authors: Bloemheuvel Stefan , van den Hoogen Jurgen , Jozinović Dario , Michelini Alberto , Atzmueller Martin
Published: August 2022

Machine learning, with its advances in deep learning has shown great potential in analyzing time series. In many scenarios, however, additional information that can potentially improve the predictions is available. This is crucial for data that arise from e. g., sensor networks that contain information about sensor locations. Then, such spatial information can be exploited by modeling it via graph structures, along with the sequential (time series) information. Recent advances in adapting deep learning to graphs have shown potential in various tasks. However, these methods have not been adapted for time series tasks to a great extent. Most attempts have essentially consolidated around time series forecasting with small sequence lengths. Generally, these architectures are not well suited for regression or classification tasks where the value to be predicted is not strictly depending on the most recent values, but rather on the whole length of the time series. We propose TISER-GCN, a novel graph neural network architecture for processing, in particular, these long time series in a multivariate regression task. Our proposed model is tested on two seismic datasets containing earthquake waveforms, where the goal is to predict maximum intensity measurements of ground shaking at each seismic station. Our findings demonstrate promising results of our approach—with an average MSE reduction of 16.3%—compared to the best performing baselines. In addition, our approach matches the baseline scores by needing only half the input size. The results are discussed in depth with an additional ablation study.
A narrative photographic approach: opening day ceremonies for Iran’s Nature Schools
Authors: Burns Edgar A. , Manouchehri Bahar , Davoudi Sina
Published: August 2022

Opening Day photographs appeared in Iran’s newspapers celebrating the succession of outdoor Nature Schools commencing each year from 2014. Using a narrative photographic approach, this qualitative study collected and analysed newspaper pictures for Iran’s Nature Schools in the half decade to 2017. At this time, government approval reflected careful planning to develop these new outdoor educational opportunities. Seven news media articles were thematically analysed from this period utilising twelve pictures. This photographic method provides another layer of understanding beyond official statements of intention, formal approval or written text. Through the local features of schools, a pattern of national intention and official endorsement can be seen, but also an awareness of invisible rules permitting outdoor learning experiences. What do these images tell us about this environmental opportunity for a new generation of schoolchildren? How do the pictures portray the urban need for the outdoors? Are there clues in these pictures of the subsequent shutting down of these outdoor schools, denying further expansion? These images tell their own story alongside formal narratives embodied in official Opening Day ceremonies and statements. We conclude these schools were meeting a strongly-felt need for the outdoors in highly urbanised contemporary Iran.
Characterization and Iron Removal Enhancement of El-Zaafarana White Sand
Authors: Ibrahim Amr F. M. , Seifelnassr Ahmed A. S. , Al-Abady Ahmed , El-Salmawy Montaser S. , Abdelaal Abdeaziem M.
Published: August 2022

Iron is a key detrimental impurity in silica sands that determines their contribution to high-technology industries. Herein, a simple ecologically sound approach is investigated for iron removal from a silica sand sample obtained from the El-Zaafarana area-Egypt. The sample was subjected to a detailed microscopic mineralogical study supported by XRD and XRF characterization. The sample was beneficiated using distilled water attrition scrubbing and screening over a 25 μm sieve followed by leaching using a mixture of equal amounts of phosphoric and oxalic acids. Leaching experiments were designed and analyzed using the Box-Behnken design (BBD) methodology. A model was developed and evaluated using the analysis of variance technique to map the relationship between the residual iron oxide in the produced concentrate and selected variables such as leaching temperature, oxalic acid, and phosphoric acid concentrations. XRD and mineralogical analysis reveal that quartz is the most dominant constituent of the studied sand and other minerals such as kaolinite, iron oxide, rutile, and zircon exist in trace amounts. The head sample shows a silica and iron oxide content of 95.69% and 2379 ppm, respectively. Attrition and separation over a 25 μm sieve increase the silica content to 97.05% and decreases the residual iron oxide to 455 ppm. The final product after leaching under optimized conditions shows 99.82% silica and 55 ppm iron oxide.
The Improved Framework for Traffic Sign Recognition Using Guided Image Filtering
Authors: Xing Jiawei , Nguyen Minh , Qi Yan Wei
Published: August 2022

In the lighting conditions such as hazing, raining, and weak lighting condition, the accuracy of traffic sign recognition is not very high due to missed detection or incorrect positioning. In this article, we propose a traffic sign recognition (TSR) algorithm based on Faster R-CNN and YOLOv5. The road signs were detected from the driver’s point of view and the view was assisted by satellite images. First, we conduct image preprocessing by using guided image filtering for the input image to remove noises. Second, the processed image is input into the proposed networks for model training and testing. Three datasets are employed to verify the effectiveness of the proposed method finally. The outcomes of the traffic sign recognition are promising.
Effect of zirconium doping on the mechanical properties of $$W_{1-x}Zr_{x}B_2$$ on the basis of first-principles calculations and magnetron sputtered films
Authors: Maździarz Marcin , Psiuk Rafał , Krawczyńska Agnieszka , Lewandowska Małgorzata , Mościcki Tomasz
Published: August 2022

Potentially superhard

$$W_{1-x}Zr_{x}B_2$$

W

1
-
x

Z

r
x

B
2

polymorphs, hP6-P6

$$_{3}$$

3

/mmc-WB

$$_2$$

2

and hP3-P6/mmm-WB

$$_2$$

2

, were thoroughly analyzed with zirconium doping in the range of x=0-25%, within the framework of the first-principles density functional theory, from both a structural and a mechanical point of view. The obtained results were subsequently compared with the properties of material deposited by the magnetron sputtering method. All predicted structures are mechanically and thermodynamically stable. Theoretical calculations suggest a decrease in hardness

$$H_v$$

H
v

and fracture toughness

$$K_{\text {IC}}$$

K
IC

of the hP6 phase with zirconium doping but no such effect on the hP3 phase. It was observed that an additional defect in the analyzed structure significantly weakens the hP6 phase but strengthens the hP3 phase. The deposited films are characterized by greater hardness but lower fracture toughness. The results of experiments show that not only is solid solution hardening responsible for strengthening the predicted new material but also the change in microstructure, the Hall–Petch effect and vacancies.
Nonlinear optimal control for the 4-DOF underactuated robotic tower crane
Authors: Rigatos G. , Abbaszadeh M. , Pomares J.
Published: August 2022

Tower cranes find wide use in construction works, in ports and in several loading and unloading procedures met in industry. A nonlinear optimal control approach is proposed for the dynamic model of the 4-DOF underactuated tower crane. The dynamic model of the robotic crane undergoes approximate linearization around a temporary operating point that is recomputed at each time-step of the control method. The linearization relies on Taylor series expansion and on the associated Jacobian matrices. For the linearized state-space model of the system a stabilizing optimal (H-infinity) feedback controller is designed. To compute the controller’s feedback gains an algebraic Riccati equation is repetitively solved at each iteration of the control algorithm. The stability properties of the control method are proven through Lyapunov analysis. The proposed control approach is advantageous because: (i) unlike the popular computed torque method for robotic manipulators, the new control approach is characterized by optimality and is also applicable when the number of control inputs is not equal to the robot’s number of DOFs, (ii) it achieves fast and accurate tracking of reference setpoints under minimal energy consumption by the robot’s actuators, (iii) unlike the popular Nonlinear Model Predictive Control method, the article’s nonlinear optimal control scheme is of proven global stability and convergence to the optimum.
Challenges, perceptions, and future preferences for post-secondary online education given experiences in the COVID-19 outbreak
Authors: Asgari Hamidreza , Gupta Rajesh , Titiloye Ibukun , Jin Xia
Published: August 2022

To gain a better understanding of online education status during and after the pandemic outbreak, this paper analyzed the data from a recent survey conducted in the state of Florida in May 2020. In particular, we focused on college students’ perception of productivity changes, benefits, challenges, and their overall preference for the future of online education. Our initial exploratory analysis showed that in most cases, students were not fully satisfied with the quality of the online education, and the majority of them suffered a plummet in their productivities. Despite the challenges, around 61% believed that they would prefer more frequent participation in online programs in the future (compared to the normal conditions before the pandemic). A structural equation model was developed to identify and assess the factors that contribute to their productivity and future preferences. The results showed that lack of sufficient communication with other students/ instructor as well as lack of required technology infrastructure significantly reduced students’ productivity. On the other hand, productivity was positively affected by perceived benefits such as flexibility and better time management. In addition, productivity played a mediating role for a number of socio-economic, demographic, and attitudinal attributes: including gender, income, technology attitudes, and home environment conflicts. Accordingly, females, high income groups, and those with home environment conflicts experienced lower productivity, which indirectly discouraged their preference for future online education. As expected, a latent pro-online education attitude increased both the productivity and the future online-education preference. Last but not the least, Gen-Xers were more likely to adopt online-education in the post pandemic conditions compared to their peers.
Management of Multiple Myeloma in the Middle East: Unmet Needs, Challenges and Perspective
Authors: Ibrahim Ahmad , Chamseddine Nabil , El-cheikh Jean , Hanna Colette , Moukadem Walid , Nasr Fady , Younis Ahmad , Bazarbachi Ali
Published: August 2022

Multiple myeloma (MM) is a prevalent hematological malignancy. Resource-constrained settings such as the Middle East are particularly burdened by the increasing trends in MM morbidity and mortality in addition to challenges in the management of MM. It thus becomes necessary to identify and address debatable areas of current practice and gaps in the management of MM in the Middle East. With a special focus on the Lebanese situation, the first-line treatment of the very elderly (> 80 years old) is discussed, in addition to the impact of relapse type (biochemical or clinical relapse) on maintenance therapy, the choice of first relapse therapy in relation to maintenance therapy, and the role of MRD in the MM treatment landscape. The need for realistic management guidelines accounting for local resources and expertise, in addition to the reflection of drug accessibility and cost on clinical practice are recognized.
Thyroid Dysfunction Among Patients with Systemic Lupus Erythematosus in Saudi Arabia
Authors: AL-Homood Ibrahim A. , Alkhathami Reem A. , Alenazi Sultan K. , Mohammed AbdelGaffar A.
Published: August 2022

Systemic lupus erythematosus (SLE) is an autoimmune disease that may be associated with other autoimmune disorders. To date, limited data are available on thyroid dysfunction and SLE in Saudi Arabia. In this retrospective study, we reviewed the cases of 151 patients with SLE. The prevalence of thyroid dysfunction was 17.2%: 4% in the hyperthyroid group and 11.9% in the hypothyroid group. Euthyroid sick syndrome was found in 1.3% of patients. Moreover, 57% of patients with hypothyroidism were positive for antibodies to thyroglobulin and thyroid peroxidase. No correlation was found between the presence of thyroid dysfunction and higher SLE disease activity, according to the Safety of Estrogens in Lupus National Assessment–Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score.
Does the Inverse Farm Size-Productivity Hypothesis Hold Beyond Five Hectares? Evidence from Ghana
Authors: Debrah Godwin , Adanu Kwami
Published: August 2022

We contribute to the inverse farm size-productivity puzzle (IR) literature by examining the relationship using a unique data set from southern Ghana that covers farms between 5 and 70 ha. The study uses an instrumental variable (IV) for land size to mitigate some effects of measurement error in land size. The inverse relationship between farm size and farm productivity is upheld when ordinary least squares estimators (OLS) are applied but becomes insignificant although still negative in the IV estimation. The results show that measurement error in land size attenuates the IR. While some studies found the IR to flatten and then become positive, this study finds that in Ghana, the IR only flattens.
Novel approach for tracking interdisciplinary research productivity using institutional databases
Authors: Bengert E. , Towle-Miller L. , Boccardo J. , Mercene G. , Ohtake P.J. , Balkundi P. , Elkin P.L. , Balthasar J. , Murphy T.F. , Noyes K.
Published: August 2022

This study proposes a new practical approach for tracking institutional changes in research teamwork and productivity using commonly available institutional electronic databases such as eCV and grant management systems. We tested several definitions of interdisciplinary collaborations based on number of collaborations and their fields of discipline. We demonstrated that the extent of interdisciplinary collaboration varies significantly by academic unit, faculty appointment and seniority. Interdisciplinary grants constitute 24% of all grants but the trend has significantly increased over the last five years. Departments with more interdisciplinary grants receive more research funding. More research is needed to improve efficiency of interdisciplinary collaborations.
Development and evaluation of a novel training program to build study staff skills in equitable and inclusive engagement, recruitment, and retention of clinical research participants
Authors: Cranfill Jessica R. , Freel Stephanie A. , Deeter Christine E. , Snyder Denise C. , Naggie Susanna , Barrett Nadine J. , Roberts Jamie N.
Published: August 2022

Background:

Adequate equitable recruitment of underrepresented groups in clinical research and trials is a national problem and remains a daunting challenge to translating research discoveries into effective healthcare practices. Engagement, recruitment, and retention (ER&R) training programs for Clinical Research Professionals (CRPs) often focus on policies and regulations. Although some training on the importance of diversity and inclusion in clinical research participation has recently been developed, there remains a need for training that couples critical equity, diversity, and inclusion (EDI) concepts with skill development in effective recruitment and retention strategies, regulations, and best practices.

Approach and methods:

We developed the ER&R Certificate program as a holistic approach to provide Duke University CRPs the opportunity to build competency in gap areas and to increase comfort in championing equitable partnerships with clinical research participants. The thirteen core and elective courses include blended learning elements, such as e-learning and wiki journaling prompts, to facilitate meaningful discussions. Pre- and post-assessments administered to CRP program participants and their managers assessed program impact on CRP skills in ER&R tasks and comfort in equitable, diverse, and inclusive engagement of clinical research participants.

Results and discussion:

Results from the first two cohorts indicate that CRPs perceived growth in their own comfort with program learning objectives, especially those centered on participant partnership and EDI principles, and most managers witnessed growth in competence and responsibility for ER&R-related tasks. Results suggest value in offering CRPs robust training programs that integrate EDI and ER&R training.
Restrictions on rational surfaces lying in very general hypersurfaces
Authors: Beheshti Roya , Riedl Eric
Published: August 2022

We study rational surfaces on very general Fano hypersurfaces in$\mathbb {P}^n$, with an eye toward unirationality. We prove that given any fixed family of rational surfaces, a very general hypersurface of degreedsufficiently close tonandnsufficiently large will admit no maps from surfaces in that family. In particular, this shows that for such hypersurfaces, any rational curve in the space of rational curves must meet the boundary. We also prove that for any fixed ratio$\alpha $, a very general hypersurface in$\mathbb {P}^n$of degreedsufficiently close tonwill admit no generically finite maps from a surface satisfying$H^2 \geq \alpha HK$, whereHis the pullback of the hyperplane class from$\mathbb {P}^n$andKis the canonical bundle on the surface.
Finite-amplitude instability of the buoyancy boundary layer in a thermally stratified medium
Authors: Xiao Yue , Li Yi , Zhao Moli , Wang Shaowei
Published: August 2022

The finite-amplitude instability of the buoyancy-driven boundary layer is considered on a vertical plate immersed in a thermally stratified ambient medium, where the wall and surrounding fluid have different temperature gradients. Although the linear stability in this configuration has been investigated, the finite-amplitude solution arising from the critical instability has been studied only for specific parameter values. We extend this by using the amplitude expansion method. The primary bifurcations to the two-dimensional least unstable mode for different temperature gradient ratios (

$0 \leqslant \lambda \leqslant 10$

) and Prandtl numbers (

$10^{-1} \leqslant Pr \leqslant 10^{4}$

) are investigated. Only supercritical bifurcations are found to occur when

$0 \leqslant \lambda < 2$

and

$Pr \leqslant 2800$

, while subcritical bifurcations are also found for larger values of temperature gradient ratio and Prandtl number. Analysis of the contribution of the nonlinear terms in the Landau coefficient reveals that the interaction of the modification of the mean flow and second harmonic for velocity with the fundamental mode for temperature plays an important role in subcritical bifurcation. Based on the Landau equation, the threshold amplitude of the nonlinear equilibrium solution is discussed as well. These encouraging results should be helpful for understanding such a buoyancy-driven flow system.
Unified approach for solving exit problems for additive-increase and multiplicative-decrease processes
Authors: van der Hofstad Remco , Kapodistria Stella , Palmowski Zbigniew , Shneer Seva
Published: August 2022

We analyse an additive-increase and multiplicative-decrease (also known as growth–collapse) process that grows linearly in time and that, at Poisson epochs, experiences downward jumps that are (deterministically) proportional to its present position. For this process, and also for its reflected versions, we consider one- and two-sided exit problems that concern the identification of the laws of exit times from fixed intervals and half-lines. All proofs are based on a unified first-step analysis approach at the first jump epoch, which allows us to give explicit, yet involved, formulas for their Laplace transforms. All eight Laplace transforms can be described in terms of two so-called scale functions associated with the upward one-sided exit time and with the upward two-sided exit time. All other Laplace transforms can be obtained from the above scale functions by taking limits, derivatives, integrals, and combinations of these.