bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of Thermal Contact Conductance in a Bundle of Flat Steel Bars
Authors: Wyczółkowski Rafał , Bagdasaryan Vazgen , Gała Marek
Published: July 2022

The phenomenon of thermal contact conduction in two-phase (fluid-solid) media determines many technological processes. An example of such a process is heat treatment of steel bars, when a heated charge has a form of a packed bundle. In order to determine the optimal heating curve it is necessary to have knowledge about the intensity of transfer through contact areas of the bars. This phenomenon is quantified by the thermal contact conductance hct. The article describes the methodology of determining the hct coefficient for bundles of flat steel bars. The starting point for the analysis is the measurement of the effective thermal conductivity kef performed for 5 × 20 mm and 10 × 20 mm bars. Individual samples of the same bars differed in arrangement. The analytical investigation used the concept of an elementary cell. This approach consisted in analysing resistances for individual heat transfer types: conduction, contact conduction and radiation. Based on the performed calculations it has been established that the value of the hct coefficient for the analysed samples is within the range 128–472 W/(m2 K). Changes of the hct coefficient in the temperature range 25–700 °C can be described with a second degree polynomial. It has been established that hct assumes maximum values in the temperature range from 300 °C to 400 °C.
Changes in the Stress Tolerance of Dwarf Rabbits in Animal-Assisted Interventions
Authors: Suba-Bokodi Éva , Nagy István , Molnár Marcell
Published: July 2022

Background: Rabbits are common companion animals in many European countries. Rabbit-assisted interventions in primary schools are suitable for decreasing the anxiety levels of children, which may increase the education efficiency of teachers. Methods: In our present study, the behavior of dwarf rabbits was tested in a children’s summer camp organized by the Family and Child Protection Service in Várpalota, Hungary, 2021. In two occasions, altogether 20 rabbits were evaluated, while 120 children were involved in the examinations. All the rabbits were the progeny of the same buck and three different does. Four of them had been previously socialized to humans during the sensitive period after birth. Results: The familiarity level of the rabbits with their owner was significantly lower after the interventions compared to the previously measured scores (p < 0.05). In the interventions, children also made behavior surveys with the rabbits in which they contacted the animals, touched them and held them. After three successive interventions, rabbits became significantly less tolerant compared to the first intervention (p < 0.05). In both cases, the rabbits who had been socialized obtained higher scores on the behavior tests compared to the non-handled conspecifics. However, by the third session, socialized rabbits showed a considerable decrease in cooperation. Conclusions: The stress tolerance of rabbits receiving handling exceeds that of those that were not handled previously. The familiarity level of the imprinted rabbits was higher in both cases: with the owner and children. When using rabbits in AAI, a maximum of two 20 min sessions is recommended for handled rabbits.
Plant Disease Detection Using Deep Convolutional Neural Network
Authors: Pandian J. , Kumar V. , Geman Oana , Hnatiuc Mihaela , Arif Muhammad , Kanchanadevi K.
Published: July 2022

In this research, we proposed a novel 14-layered deep convolutional neural network (14-DCNN) to detect plant leaf diseases using leaf images. A new dataset was created using various open datasets. Data augmentation techniques were used to balance the individual class sizes of the dataset. Three image augmentation techniques were used: basic image manipulation (BIM), deep convolutional generative adversarial network (DCGAN) and neural style transfer (NST). The dataset consists of 147,500 images of 58 different healthy and diseased plant leaf classes and one no-leaf class. The proposed DCNN model was trained in the multi-graphics processing units (MGPUs) environment for 1000 epochs. The random search with the coarse-to-fine searching technique was used to select the most suitable hyperparameter values to improve the training performance of the proposed DCNN model. On the 8850 test images, the proposed DCNN model achieved 99.9655% overall classification accuracy, 99.7999% weighted average precision, 99.7966% weighted average recall, and 99.7968% weighted average F1 score. Additionally, the overall performance of the proposed DCNN model was better than the existing transfer learning approaches.
Influence of Recipe Factors on the Structure and Properties of Non-Autoclaved Aerated Concrete of Increased Strength
Authors: Stel’makh Sergey A. , Shcherban’ Evgenii M. , Beskopylny Alexey N. , Mailyan Levon R. , Meskhi Besarion , Beskopylny Nikita , Dotsenko Natal’ya , Kotenko Maria
Published: July 2022

At present, the load-bearing enclosing structures of buildings and structures are designed and built considering the increasing requirements for energy efficiency and energy saving of such structures. This is due to the need for a thrifty attitude to the energy consumed and the need to strive for the greening of construction and increase the energy efficiency of buildings and structures. In this regard, one of the most effective and proven building materials is cellular concrete. The purpose of this study was to study the influence of some prescription factors on the structure formation and properties of non-autoclaved aerated concrete with improved characteristics. Standard test methods were used, as well as SEM analysis of the structure of aerated concrete. Non-autoclaved aerated concrete with the replacement of part of the cement with microsilica in an amount from 4% to 16% MS showed higher strength characteristics compared to aerated concrete, where part of the cement was replaced by the addition of granulated blast-furnace slag and a complex additive. The maximum value of compressive strength was recorded for aerated concrete with 16% MS addition. The largest increase in the coefficients of constructive quality was observed in compositions of aerated concrete with the addition of silica fume from 11% to 46% compared with the control composition. The addition of microsilica makes it possible to achieve an improvement in the thermal conductivity characteristics of non-autoclaved aerated concrete (up to 10%). Replacing part of the cement with slag and complex additives does not have a significant effect on thermal conductivity. The obtained dependencies were confirmed by the analysis of the structure formation of the studied aerated concrete at the micro level. An improvement in the microstructure of aerated concrete with the addition of microsilica in comparison with samples of the control composition has been proven.
Experimental Investigation of Steam Conformance Evolution in Vertical-CSS and Optimization of Profile Improvement Agents
Authors: Lei Chunyan , Wu Yongbin , Yang Guo
Published: July 2022

Production performance of heavy oil deposits in Xinjiang oilfield developed by vertical-well cyclic steam stimulation (CSS) is increasingly challenged by reservoir heterogeneity, which is comprised of original sedimental heterogeneity and steam-induced heterogeneity. In order to understand the impacts of sedimental heterogeneity and high-speed steam injection to steam conformance, and strategies to maximize steam swept volume, a series of experiments were designed and implemented. Three-tube coreflooding experiments were performed to study the steam displacement dynamics under heterogeneous conditions, and a high-temperature plugging agent was developed. The coreflooding experiments indicate that the injection conformance deteriorates once the steam breakthrough occurs in a high-permeability tube, leaving the oil in the medium and low permeability tubes being surpassed. The optimized plugging agent could resist high temperatures over 260 °C and its compressive strength was 13.14 MPa, which is higher than maximal steam injection pressure. The plugging rate of high permeability core was greater than 99.5% at 220–280 °C with a breakthrough pressure gradient over 25 MPa/m. The field test validated its profile improvement feasibility with cyclic oil, 217.6% of the previous cycle. The plugging agent optimized in this study has significant potential for similar heterogeneous reservoirs.
The Spatio–Temporal Variation of Spring Frost in Xinjiang from 1971 to 2020
Authors: Yue Zhiyang , Xu Zhonglin , Wang Yao
Published: July 2022

Under the background of intensifying global change, the frequent occurrence of agrometeorological disasters has an adverse impact on the social economy. Low-temperature weather in spring is one of the main agrometeorological disasters in Xinjiang. Studying the spatial and temporal characteristics of low temperatures in spring in Xinjiang is of great significance. However, research on the spatiotemporal variation of spring frost in arid areas is currently lacking, which limits our understanding of the occurrence and development mechanism of typical disastrous weather events in arid areas. Therefore, on the basis of the daily meteorological data of 40 meteorological stations in the Xinjiang Province of China from 1971 to 2020, we studied the spatiotemporal heterogeneity of spring frost in Xinjiang through trend analysis, the Mann–Kendall test, Kriging interpolation, and wavelet analysis. Results showed that the frequency of spring frost had the spatial trend from Northern Xinjiang to Southern Xinjiang. The occurrence frequency of spring frost in the entire and northern region of Xinjiang had an upward trend, whereas that in Southern Xinjiang showed a downward trend. Severe and moderate spring frost events mainly occurred in Xinjiang. The duration of spring frost had the characteristics of Northern Xinjiang to Southern Xinjiang. The spring frost in Northern Xinjiang mainly occurred in April, and that of Southern Xinjiang was in March. Obvious 15-, 10-, and 20-year oscillation cycles were observed in the occurrence frequency of spring frost in the entire, southern, and northern regions of Xinjiang, respectively. This study can provide a useful reference for the prediction and research corresponding to the occurrence mechanism of spring frost in arid areas.
A Novel Early Cretaceous Flower and Its Implications on Flower Derivation
Authors: Wang Xin
Published: July 2022

Background: The origin and early evolution of angiosperms, by far the most important plant group for human beings, are questions demanding answers, mainly due to a lack of related fossils. The Yixian Formation (Lower Cretaceous) is famous for its fossils of early angiosperms, and several Early Cretaceous angiosperms with apocarpous gynoecia have been documented. However, a hypanthium and an inferior ovary are lacking in these fossil angiosperms. Methods: The specimen was collected from the outcrop of the Yixian Formation in Dawangzhangzi in the suburb of Lingyuan, Liaoning, China. The specimen was photographed using a Nikon D200 digital camera, and its details were photographed using a Nikon SMZ1500 stereomicroscope and a MAIA3 TESCAN SEM. Results: A fossil angiosperm, Lingyuananthus inexpectus gen. et sp. nov, is reported from the Lower Cretaceous of China. Differing from those documented previously, Lingyuananthus has a hypanthium, an inferior ovary, and ovules inside its ovary. Such a character assemblage indicates its angiospermous affinity, although not expected by any existing leading angiosperm evolutionary theory. Conclusions: New fossil material with a unique character assemblage falls beyond the expectation of the currently widely accepted theories of angiosperm evolution. Together with independently documented fossils of early angiosperms, Lingyuananthus suggests that at least some early angiosperms’ flowers can be derived in a way that has been ignored previously.
Integrating Conformational Dynamics and Perturbation-Based Network Modeling for Mutational Profiling of Binding and Allostery in the SARS-CoV-2 Spike Variant Complexes with Antibodies: Balancing Local and Global Determinants of Mutational Escape Mechanisms
Authors: Verkhivker Gennady , Agajanian Steve , Kassab Ryan , Krishnan Keerthi
Published: July 2022

In this study, we combined all-atom MD simulations, the ensemble-based mutational scanning of protein stability and binding, and perturbation-based network profiling of allosteric interactions in the SARS-CoV-2 spike complexes with a panel of cross-reactive and ultra-potent single antibodies (B1-182.1 and A23-58.1) as well as antibody combinations (A19-61.1/B1-182.1 and A19-46.1/B1-182.1). Using this approach, we quantify the local and global effects of mutations in the complexes, identify protein stability centers, characterize binding energy hotspots, and predict the allosteric control points of long-range interactions and communications. Conformational dynamics and distance fluctuation analysis revealed the antibody-specific signatures of protein stability and flexibility of the spike complexes that can affect the pattern of mutational escape. A network-based perturbation approach for mutational profiling of allosteric residue potentials revealed how antibody binding can modulate allosteric interactions and identified allosteric control points that can form vulnerable sites for mutational escape. The results show that the protein stability and binding energetics of the SARS-CoV-2 spike complexes with the panel of ultrapotent antibodies are tolerant to the effect of Omicron mutations, which may be related to their neutralization efficiency. By employing an integrated analysis of conformational dynamics, binding energetics, and allosteric interactions, we found that the antibodies that neutralize the Omicron spike variant mediate the dominant binding energy hotpots in the conserved stability centers and allosteric control points in which mutations may be restricted by the requirements of the protein folding stability and binding to the host receptor. This study suggested a mechanism in which the patterns of escape mutants for the ultrapotent antibodies may not be solely determined by the binding interaction changes but are associated with the balance and tradeoffs of multiple local and global factors, including protein stability, binding affinity, and long-range interactions.
The Effect of Self-Selected Exercise Workloads on Perceived Enjoyment and Self-Efficacy in Sedentary Adults
Authors: Waaso Peyton , Gofton Natalie , Zuhl Micah
Published: July 2022

Self-selected workloads are shown to be more enjoyable than researcher-selected workloads. In addition, it is unclear if sedentary adults find aerobic interval or continuous exercise more pleasant. Therefore, the primary purpose of this study was to determine the effects of two acute bouts (interval vs. continuous) of self-selected moderate-intensity treadmill exercises on perceived enjoyment and self-efficacy towards exercise in a sedentary cohort. Methods: Sixteen sedentary adults completed two 30 min bouts of moderate-intensity treadmill activity, one interval and one continuous. Participants blindly (could not see speed, grade, and heart rate) selected their own treadmill workload with guidance from the Borg RPE 6–20 scale. Post-exercise self-efficacy and perceived enjoyment were assessed using the Self-Efficacy for Exercise Scale and the Physical Activity Enjoyment Scale, respectively. Exercise workloads using treadmill speed and grade and exercise heart rate were compared between trials. Results: No significant differences were found between conditions for self-selected workloads (p = 0.62), self-efficacy (p = 0.58), perceived enjoyment (p = 0.41), and heart rate (p = 0.12). Discussion: Sedentary individuals reported no difference in self-efficacy or perceived exercise enjoyment. Participants were, however, adequate in self-selecting their own intensities with RPE guidance as there were no differences in the workloads across conditions. These results suggest that when able to self-select moderate-intensity exercise workloads, sedentary individuals equally enjoy both interval and continuous exercise.
Accurate Screening for Early-Stage Breast Cancer by Detection and Profiling of Circulating Tumor Cells
Authors: Crook Timothy , Leonard Robert , Mokbel Kefah , Thompson Alastair , Michell Michael , Page Raymond , Vaid Ashok , Mehrotra Ravi , Ranade Anantbhushan , Limaye Sewanti , Patil Darshana , Akolkar Dadasaheb , Datta Vineet , Fulmali Pradip , Apurwa Sachin , Schuster Stefan , Srinivasan Ajay , Datar Rajan
Published: July 2022

Background: The early detection of breast cancer (BrC) is associated with improved survival. We describe a blood-based breast cancer detection test based on functional enrichment of breast-adenocarcinoma-associated circulating tumor cells (BrAD-CTCs) and their identification via multiplexed fluorescence immunocytochemistry (ICC) profiling for GCDFP15, GATA3, EpCAM, PanCK, and CD45 status. Methods: The ability of the test to differentiate BrC cases (N = 548) from healthy women (N = 9632) was evaluated in a case–control clinical study. The ability of the test to differentiate BrC cases from those with benign breast conditions was evaluated in a prospective clinical study of women (N = 141) suspected of BrC. Results: The test accurately detects BrAD-CTCs in breast cancers, irrespective of age, ethnicity, disease stage, grade, or hormone receptor status. Analytical validation established the high accuracy and reliability of the test under intended use conditions. The test detects and differentiates BrC cases from healthy women with 100% specificity and 92.07% overall sensitivity in a case–control study. In a prospective clinical study, the test shows 93.1% specificity and 94.64% overall sensitivity in differentiating breast cancer cases (N = 112) from benign breast conditions (N = 29). Conclusion: The findings reported in this manuscript support the clinical potential of this test for blood-based BrC detection.
Increased Soluble PD-1 Predicts Response to Nivolumab plus Ipilimumab in Melanoma
Authors: Pedersen Jesper , Sokac Mateo , Sørensen Boe , Luczak Adam , Aggerholm-Pedersen Ninna , Birkbak Nicolai , Øllegaard Trine , Jakobsen Martin
Published: July 2022

Background: Checkpoint inhibitors have revolutionized the treatment of metastatic melanoma, yielding long-term survival in a considerable proportion of the patients. Yet, 40–60% of patients do not achieve a long-term benefit from such therapy, emphasizing the urgent need to identify biomarkers that can predict response to immunotherapy and guide patients for the best possible treatment. Here, we exploited an unsupervised machine learning approach to identify potential inflammatory cytokine signatures from liquid biopsies, which could predict response to immunotherapy in melanoma. Methods: We studied a cohort of 77 patients diagnosed with unresectable advanced-stage melanoma undergoing treatment with first-line nivolumab plus ipilimumab or pembrolizumab. Baseline and on-treatment plasma samples were tested for levels of PD-1, PD-L1, IFNγ, IFNβ, CCL20, CXCL5, CXCL10, IL6, IL8, IL10, MCP1, and TNFα and analyzed by Uniform Manifold Approximation and Projection (UMAP) dimension reduction method and k-means clustering analysis. Results: Interestingly, using UMAP analysis, we found that treatment-induced cytokine changes measured as a ratio between baseline and on-treatment samples correlated significantly to progression-free survival (PFS). For patients treated with nivolumab plus ipilimumab we identified a group of patients with superior PFS that were characterized by significantly higher baseline-to-on-treatment increments of PD-1, PD-L1, IFNγ, IL10, CXCL10, and TNFα compared to patients with worse PFS. Particularly, a high PD-1 increment was a strong individual predictor for superior PFS (HR = 0.13; 95% CI 0.034–0.49; p = 0.0026). In contrast, decreasing levels of IFNγ and IL6 and increasing levels of CXCL5 were associated with superior PFS in the pembrolizumab group, although none of the cytokines were individually predictors for PFS. Conclusions: In short, our study demonstrates that a high increment of PD-1 is associated with superior PFS in advanced-stage melanoma patients treated with nivolumab plus ipilimumab. In contrast, decreasing levels of IFNγ and IL6, and increasing levels of CXCL5 are associated with response to pembrolizumab. These results suggest that using serial samples to monitor changes in cytokine levels early during treatment is informative for treatment response.
Circulating Exosome Cargoes Contain Functionally Diverse Cancer Biomarkers: From Biogenesis and Function to Purification and Potential Translational Utility
Authors: Mitchell Megan I. , Ma Junfeng , Carter Claire L. , Loudig Olivier
Published: July 2022

Although diagnostic and therapeutic treatments of cancer have tremendously improved over the past two decades, the indolent nature of its symptoms has made early detection challenging. Thus, inter-disciplinary (genomic, transcriptomic, proteomic, and lipidomic) research efforts have been focused on the non-invasive identification of unique “silver bullet” cancer biomarkers for the design of ultra-sensitive molecular diagnostic assays. Circulating tumor biomarkers, such as CTCs and ctDNAs, which are released by tumors in the circulation, have already demonstrated their clinical utility for the non-invasive detection of certain solid tumors. Considering that exosomes are actively produced by all cells, including tumor cells, and can be found in the circulation, they have been extensively assessed for their potential as a source of circulating cell-specific biomarkers. Exosomes are particularly appealing because they represent a stable and encapsulated reservoir of active biological compounds that may be useful for the non-invasive detection of cancer. T biogenesis of these extracellular vesicles is profoundly altered during carcinogenesis, but because they harbor unique or uniquely combined surface proteins, cancer biomarker studies have been focused on their purification from biofluids, for the analysis of their RNA, DNA, protein, and lipid cargoes. In this review, we evaluate the biogenesis of normal and cancer exosomes, provide extensive information on the state of the art, the current purification methods, and the technologies employed for genomic, transcriptomic, proteomic, and lipidomic evaluation of their cargoes. Our thorough examination of the literature highlights the current limitations and promising future of exosomes as a liquid biopsy for the identification of circulating tumor biomarkers.
Lymphocyte Exhaustion in AML Patients and Impacts of HMA/Venetoclax or Intensive Chemotherapy on Their Biology
Authors: Zhigarev Dmitry , Varshavsky Asya , MacFarlane Alexander W. , Jayaguru Prathiba , Barreyro Laura , Khoreva Marina , Dulaimi Essel , Nejati Reza , Drenberg Christina , Campbell Kerry S.
Published: July 2022

Acute myeloid leukemia (AML) is an aggressive malignancy that requires rapid treatment with chemotherapies to reduce tumor burden. However, these chemotherapies can compromise lymphocyte function, thereby hindering normal anti-tumor immune responses and likely limiting the efficacy of subsequent immunotherapy. To better understand these negative impacts, we assessed the immunological effects of standard-of-care AML therapies on lymphocyte phenotype and function over time. When compared to healthy donors, untreated AML patients showed evidence of lymphocyte activation and exhaustion and had more prevalent CD57+NKG2C+ adaptive NK cells, which was independent of human cytomegalovirus (HCMV) status. HMA/venetoclax treatment resulted in a greater fraction of T cells with effector memory phenotype, inhibited IFN-γ secretion by CD8+ T cells, upregulated perforin expression in NK cells, downregulated PD-1 and 2B4 expression on CD4+ T cells, and stimulated Treg proliferation and CTLA-4 expression. Additionally, we showed increased expression of perforin and CD39 and enhanced IFN-γ production by T cells from pre-treatment blood samples of venetoclax-resistant AML patients. Our results provide insight into the lymphocyte status in previously untreated AML patients and the effects of standard-of-care treatments on their biology and functions. We also found novel pre-treatment characteristics of T cells that could potentially predict venetoclax resistance.
Biomarkers of Trastuzumab-Induced Cardiac Toxicity in HER2- Positive Breast Cancer Patient Population
Authors: Grela-Wojewoda Aleksandra , Püsküllüoğlu Mirosława , Sas-Korczyńska Beata , Zemełka Tomasz , Pacholczak-Madej Renata , Wysocki Wojciech M. , Wojewoda Tomasz , Adamczyk Agnieszka , Lompart Joanna , Korman Michał , Mucha-Małecka Anna , Ziobro Marek , Konduracka Ewa
Published: July 2022

Trastuzumab-induced cardiotoxicity (TIC) can lead to early treatment discontinuation. The aim of this study was to evaluate: N-terminal brain natriuretic peptide (NT-proBNP), creatine kinase-MB (CK-MB), myoglobin, and selected biochemical and clinical factors as predictors of TIC. One hundred and thirty patients with HER2-positive BC receiving adjuvant trastuzumab therapy (TT) were enrolled. Measurement of cardiac markers and biochemical tests as well as echocardiography were performed prior to TT initiation and every three months thereafter. Cardiotoxicity leading to treatment interruption occurred in 24 patients (18.5%). While cardiotoxicity caused early treatment discontinuation in 14 patients (10.8%), the TIC resolved in 10 (7.7%) and TT was resumed. The most common complication was a decrease in left ventricular ejection fraction of more than 10% from baseline or below 50% (7.7%). In patients with TIC, there was no increase in the levels of NT-proBNP, myoglobin, and CK-MB. BMI, hypertension, ischemic heart disease, diabetes, age, cancer stage, type of surgery, use of radiotherapy, chemotherapy, and hormone therapy were shown to not have an effect on TIC occurrence. NT-proBNP, myoglobin, and CK-MB are not predictors of TIC. There is an ongoing need to identify biomarkers for TIC.
Importance of Optical Coherence Tomography and Optical Coherence Tomography Angiography in the Imaging and Differentiation of Choroidal Melanoma: A Review
Authors: Obuchowska Iwona , Konopińska Joanna
Published: July 2022

Choroidal melanoma requires reliable and precise clinical examination and diagnosis to differentiate it from benign choroidal nevi. To achieve accurate diagnosis, as well as monitoring the progression of disease, various imaging modalities are used, including non-invasive optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). This review begins with a historical account of the development of OCT and OCTA and the methods of generation of images. This outlines the understanding of what OCT/OCTA images show, as well as how image artifacts arise. The anatomy and imaging of specific vascular layers of the eye are introduced. Then, anatomical aspects of choroidal melanoma, its diagnosis and differentiation from metastasis, and choroidal nevi are presented. The purpose of this review is to critically evaluate application of OCT and OCTA in the diagnosis of choroidal melanoma.
Innovation for the Sake of Innovation? How Does Robotic Hepatectomy Compare to Laparoscopic or Open Resection for HCC—A Systematic Review and Meta-Analysis
Authors: Murtha-Lemekhova Anastasia , Fuchs Juri , Hoffmann Katrin
Published: July 2022

Robot-assisted hepatectomy is a novel approach to treat liver tumors. HCC is on the rise as the cause of cancer and mortality and is often preceded by cirrhosis. Robot-assisted hepatectomy has been suggested to offer benefits to cirrhotic patients. We aimed to evaluate current evidence for robot-assisted hepatectomy for HCC and compare it to open and laparoscopic approaches. This systematic review and meta-analysis has been conducted in accordance with most recent PRISMA recommendations and the protocol has been registered at PROSPERO (CRD42022328544). There were no randomized controlled trials available and no study focused on cirrhotic patients exclusively. Robot-assisted hepatectomy was associated with less major complications than the laparoscopic approach, but comparable with open hepatectomy. No difference was seen in overall or minor complications, as well as liver specific or infectious complications. Cumulative survivals were similar in robot-assisted hepatectomy and laparoscopic or open approaches. There is a clear lack of evidence to suggest particular benefits for robot-assisted hepatectomy in cirrhotic patients. Otherwise, the robot-assisted approach has similar complication rates as open or laparoscopic methods. Non-industry driven randomized controlled trials are needed to evaluate the efficacy of robot-assisted liver surgery.
Cu/Zn/Zr/Ga Catalyst for Utilisation of Carbon Dioxide to Methanol—Kinetic Equations
Authors: Hamryszak Łukasz , Madej-Lachowska Maria , Grzesik Mirosław , Śliwa Michał
Published: July 2022

This paper presents the kinetics of methanol synthesis from carbon dioxide and hydrogen over a Cu/Zn/Zr/Ga catalyst. Kinetic studies were carried out in a continuous-flow fixed-bed reactor in a temperature range from 433 to 513 K, pressures from 3 to 8 MPa, and GHSV from 1660 to 10,000 1/h for initial molar fractions of hydrogen from about 0.48 to 0.70, carbon dioxide from 0.05 to about 0.22, and carbon monoxide from 0 to about 0.07. Significant effects of temperature and the composition of the reaction mixture on the conversion degrees α1 and α2 were found. The Cu/Zn/Zr/Ga catalyst showed good stability over 960 h. XRD and CO2TPD characterisation were performed. Thefinally obtained results of kinetic tests were developed in the form of Langmuir–Hinshelwood kinetic equations. The numerical Levenberg–Marquardt method was used to estimate the kinetic equations. The average relative error of fitting the kinetic equations to the experimental data was 18%.
Synthesis of Self-Supported Cu/Cu3P Nanoarrays as an Efficient Electrocatalyst for the Hydrogen Evolution Reaction
Authors: Dang Rui , Xu Xiufeng , Xie Mengmeng , Liu Jian
Published: July 2022

Owing to the energy crisis and environmental pollution, it is essential to develop cheap, environmentally friendly and sustainable energy to replace noble metal electrocatalysts for use in the hydrogen evolution reaction (HER). We report herein that a Cu/Cu3P nanoarray catalyst was directly grown on the surfaces of Cu nanosheets from its Cu/CuO nanoarray precursor by a low-temperature phosphidation process. In particular, the effects of phosphating distance, mass ratio and temperature on the morphology of Cu/Cu3P nanoarrays were studied in detail. This nanoarray, as an electrocatalyst, displays excellent catalytic performance and long-term stability in an acid solution for electrochemical hydrogen generation. Specifically, the Cu/Cu3P nanoarray-270 exhibits a low onset overpotential (96 mV) and a small Tafel slope (131 mV dec−1).
Effects of TP53 Mutations and miRs on Immune Responses in the Tumor Microenvironment Important in Pancreatic Cancer Progression
Authors: McCubrey James A. , Yang Li V. , Abrams Stephen L. , Steelman Linda S. , Follo Matilde Y. , Cocco Lucio , Ratti Stefano , Martelli Alberto M. , Augello Giuseppa , Cervello Melchiorre
Published: July 2022

Approximately 90% of pancreatic cancers are pancreatic ductal adenocarcinomas (PDAC). PDAC is the fourth leading cause of cancer death world-wide. Therapies for PDAC are largely ineffective due to the dense desmoplastic tumor microenvironment which prevents chemotherapeutic drugs and small molecule inhibitors from exerting effective anti-cancer effects. In this review, we will discuss the roles of TP53 and miRs on the PDAC tumor microenvironment and how loss of the normal functions of TP53 promote tumor progression. The TP53 gene is mutated in approximately 50% of pancreatic cancers. Often, these TP53 mutations are point mutations which confer additional functions for the TP53 proteins. These are called gain of function (GOF) mutations (mut). Another class of TP53 mutations are deletions which result in loss of the TP53 protein; these are referred to TP53-null mutations. We have organized this review into various components/properties of the PDAC microenvironment and how they may be altered in the presence of mutant TP53 and loss of certain miR expression.
Recent Progress in Electric Furnace Titanium Slag Processing and Utilization: A Review
Authors: Jing Jianfa , Guo Yufeng , Wang Shuai , Chen Feng , Yang Lingzhi , Qiu Guanzhou
Published: July 2022

Titanium slags produced through ilmenite electric furnace smelting contain 60–80%TiO2, a vital titanium resource in the titanium industry. The processing and utilization of titanium slag is faced with many challenges, such as complex mineral structures, high requirements, severe environmental pollution, and heavy additives and energy consumption. This study aims to review the technologies for the processing and utilization of titanium slag. First, we analyze the characteristics of titanium slag from different regions. Then, we discuss in detail the methods for processing and using titanium slag. The progress in electric furnace titanium slag processing and utilization can be divided into two areas: the preparation of titanium dioxide and high-quality titanium-rich materials. These include H2SO4 leaching, HCl leaching, fluoride leaching, sulfur roasting–leaching, alkaline roasting–leaching, oxide roasting–leaching, oxidation and reduction roasting–leaching, phosphorylation roasting–leaching, and ammonia decomposition leaching. Further development of oxide roasting–leaching for the extraction of titanium from titanium slag is recommended.
Tailoring the Evidence for Exercise Oncology within Breast Cancer Care
Authors: Wagoner Chad W. , Capozzi Lauren C. , Culos-Reed S. Nicole
Published: July 2022

Exercise is safe and effective for those living with and beyond breast cancer, with evidence supporting exercise guidelines, and position statements from international organizations. Despite the clearly recognized benefits of exercise for these individuals, many do not participate or maintain recommended exercise levels throughout the breast cancer continuum, highlighting the lack of translation from research into practice. In addition, discerning how exercise can be tailored to address breast cancer-related impairments, so that individuals are able to participate safely and effectively, has also not been studied extensively. Thus, we propose that implementing exercise screening, triage, and referral pathways across the breast cancer continuum may allow for increased accessibility and adoption among those living with and beyond breast cancer. This paper provides an overview of exercise prescription tailoring for common breast cancer and treatment-related impairments, proposes a simplified screening tool for identifying physical activity and movement-related impairments, and considers how best to channel evidence into practice via proposed implementation pathways that may better connect individuals living with and beyond breast cancer with exercise oncology resources through screening, triage, and referral.
A Novel Method for Pattern Recognition of GIS Partial Discharge via Multi-Information Ensemble Learning
Authors: Jing Qianzhen , Yan Jing , Lu Lei , Xu Yifan , Yang Fan
Published: July 2022

Partial discharge (PD) is the main feature that effectively reflects the internal insulation defects of gas-insulated switchgear (GIS). It is of great significance to diagnose the types of insulation faults by recognizing PD to ensure the normal operation of GIS. However, the traditional diagnosis method based on single feature information analysis has a low recognition accuracy of PD, and there are great differences in the diagnosis effect of various insulation defects. To make the most of the rich insulation state information contained in PD, we propose a novel multi-information ensemble learning for PD pattern recognition. First, the ultra-high frequency and ultrasonic data of PD under four typical defects of GIS are obtained through experiment. Then the deep residual convolution neural network is used to automatically extract discriminative features. Finally, multi-information ensemble learning is used to classify PD types at the decision level, which can complement the shortcomings of the independent recognition of the two types of feature information and has higher accuracy and reliability. Experiments show that the accuracy of the proposed method can reach 97.500%, which greatly improves the diagnosis accuracy of various insulation defects.
AutoMH: Automatically Create Evolutionary Metaheuristic Algorithms Using Reinforcement Learning
Authors: Almonacid Boris
Published: July 2022

Machine learning research has been able to solve problems in multiple domains. Machine learning represents an open area of research for solving optimisation problems. The optimisation problems can be solved using a metaheuristic algorithm, which can find a solution in a reasonable amount of time. However, the time required to find an appropriate metaheuristic algorithm, that would have the convenient configurations to solve a set of optimisation problems properly presents a problem. The proposal described in this article contemplates an approach that automatically creates metaheuristic algorithms given a set of optimisation problems. These metaheuristic algorithms are created by modifying their logical structure via the execution of an evolutionary process. This process employs an extension of the reinforcement learning approach that considers multi-agents in their environment, and a learning agent composed of an analysis process and a process of modification of the algorithms. The approach succeeded in creating a metaheuristic algorithm that managed to solve different continuous domain optimisation problems from the experiments performed. The implications of this work are immediate because they describe a basis for the generation of metaheuristic algorithms in an online-evolution.
A Theoretical Analysis of Favorable Propagation on Massive MIMO Channels with Generalized Angle Distributions
Authors: Zhang Yuxiang , Zhang Jianhua , Zhang Jian , Liu Guangyi , Zhang Yuan , Yao Yuan
Published: July 2022

Massive MIMO obtains the multiuser performance gain based on the favorable propagation (FP) assumption, defined as the mutual orthogonality of different users’ channel vectors. Until now, most of the theoretical analyses of FP are based on uniform angular distributions and only consider the horizontal dimension. However, the real propagation channel contains full dimensions, and the spatial angle varies with the environment. Thus, it remains unknown whether the FP condition holds in real deployment scenarios and how it impacts the massive MIMO system performance. In this paper, we analyze the FP condition theoretically based on a cluster-based three-dimensional (3D) MIMO channel with generalized angle distributions. Firstly, the FP condition’s unified mathematical expectation and variance expressions with full-dimensional angular integral are given. Since the closed-form expressions are hard to derive, we decompose generalized angle distributions, i.e., wrapped Gaussian (WG), Von Mises (VM), and truncated Laplacian (TL) into the functions of Bessel and Cosine basis by introducing Jacobi-Anger expansions and Fourier series. Thus the closed-form expressions of the FP condition are derived. Based on the above, we theoretically analyze the asymptotically FP condition under generalized angle distributions and then compare the impact of angular spreads on the FP performance. Furtherly, the FP condition is also investigated by numerical simulations and practical measurements. It is observed that environments with larger angle spreads and larger antenna spacing are more likely to realize FP. This paper provides valuable insights for the theoretical analysis of the practical application of massive MIMO systems.
MTM-Inspired Graphene-Based THz MIMO Antenna Configurations Using Characteristic Mode Analysis for 6G/IoT Applications
Authors: Khaleel Sherif A. , Hamad Ehab K. I. , Parchin Naser Ojaroudi , Saleh Mohamed B.
Published: July 2022

6G wireless communications will be immersed in the future with different applications. It is expected to support all IoT services and satellite communications, and it is expected to support artificial intelligence (AI) and machine learning (ML). The THz frequency band has a vital role in 6G communication. In this study, a new graphene plasmonic two-port Terahertz (THz) MIMO antenna is analyzed by the characteristic mode theory (CMA), which gives a better insight into the physical behavior of the MIMO configurations. The proposed MIMO antenna is compact and designed on a Teflon substrate of 130 × 85 µm2. The antenna provides a wide impedance bandwidth of 0.6 THz (3.2–3.8 THz). The CMA is applied to clarify the position at which the mutual coupling gives a maximum concentrated current distribution. It is mainly used to reveal the preferable MIMO antenna configuration by the usage of the model significant and model current distribution property. To reduce the mutual coupling between the radiating elements, a complementary dumbbell-structure Metamaterial (MTM) unit cell is etched in the ground plane to block the coupling mode without any affection on the dominant mode. The preferred MIMO configuration gives high isolation of −55 dB between the radiating patches. The fundamental characteristics have been discussed in detail. The proposed MIMO design offers several attractive features such as large bandwidth of 0.6 THz, low envelope correlation coefficient (ECC) of 0.000168, compact size, stable radiation, high gain of 7.23 dB, and low channel capacity loss (CCL) of 0.006. The proposed MIMO design is suitable for different applications in the THz band according to the high-performance parameters such as biomedical applications, security scanning, sensing, IoT, and 6G high-speed wireless communication systems.
Modeling Electrical Conductivity of Metal Meshes for Predicting Shielding Effectiveness in Magnetic Fields of Wireless Power Transfer Systems
Authors: Zimmer Steve , Helwig Martin , Winkler Anja , Modler Niels
Published: July 2022

The dimensioning of wireless power transfer systems requires compliance with safety standards for human exposure and electromagnetic compatibility. For this reason, shielding is conventionally carried out with heavy and costly plates. In order to evaluate a lightweight and low-cost alternative, this paper presents a comprehensive investigation of the shielding effectiveness of metal meshes in magnetic fields of wireless power transfer systems, including analytical modeling and experimental validation. Special emphasis is laid on the validation of novel analytical approximation approaches to model the anisotropic electrical conductivity of metal meshes. The proposed approaches show good consistency of the mean value taking into account warp and weft direction, whereas the modeling of the anisotropic behavior is not sufficiently accurately represented. Using the calculated electrical conductivity, the analytical modeling of the maximum shielding effectiveness based on a literature-known approach is very consistent for the experimental validation. Thus, the performed studies provide a significant contribution to the dimensioning of metal meshes as shielding for wireless power transfer systems.
Joint Inversion of Evaporation Duct Based on Radar Sea Clutter and Target Echo Using Deep Learning
Authors: Ji Hanjie , Yin Bo , Zhang Jinpeng , Zhang Yushi
Published: July 2022

Tropospheric duct is an anomalous atmospheric phenomenon over the sea surface that seriously affects the normal operation and performance evaluation of electromagnetic communication equipment at sea. Therefore, achieving precise sensing of tropospheric duct is of profound significance for the propagation of electromagnetic signals. The approach of inverting atmospheric refractivity from easily measurable radar sea clutter is also known as the refractivity from clutter (RFC) technique. However, inversion precision of the conventional RFC technique is low in the low-altitude evaporation duct environment. Due to the weak attenuation of the over-the-horizon target signal as it passes through the tropospheric duct, its strength is much stronger than that of sea clutter. Therefore, this study proposes a new method for the joint inversion of evaporation duct height (EDH) based on sea clutter and target echo by combining deep learning. By testing the inversion performance and noise immunity of the new joint inversion method, the experimental results show that the mean error RMSE and MAE of the new method proposed in this paper are reduced by 41.2% and 40.3%, respectively, compared with the conventional method in the EDH range from 0 to 40 m. In particular, the RMSE and MAE in the EDH range from 0 to 16.7 m are reduced by 54.2% and 56.4%, respectively, compared with the conventional method. It shows that the target signal is more sensitive to the lower evaporation duct, which obviously enhances the inversion precision of the lower evaporation duct and has effectively improved the weak practicality of the conventional RFC technique.
Arc Grounding Fault Monitoring and Fire Prediction Method Based on EEMD and Reconstruction
Authors: Li Bingyu , Du Xuhao , Miao Junjie , Wang Haobin , Ma Yanqiang , Li Zheng
Published: July 2022

To solve the problem of the single-phase ground fault and occurrence of electrical fires due to the residual current in substation AC power systems, a residual current intelligent sensing technology is proposed based on ensemble empirical modal decomposition (EEMD), sample entropy (SE) reconstruction, and fire warning technology using a beetle antennae search algorithm. First, through the residual current monitoring device to collect residual current information, EEMD and SE reconstruction for arc-earth fault diagnosis and an analysis of the differences in the current characteristics of each line after reconstruction are used to determine the fault line. Second, residual current, temperature, and operating voltage as input parameters and fire probability are the output parameters. The input–output relationship is established by a back-propagation neural network (BPNN) and optimized by the beetle antennae search (BAS) algorithm to speed up the convergence and improve the prediction accuracy to establish a substation fire warning scheme. Through simulation experiments, this paper proposes the residual current as a monitoring object method can effectively diagnose ground faults and accurately predict the probability of fire occurrence to ensure the safe and stable operation of substations.
Reviewing Explanatory Methodologies of Electricity Markets: An Application to the Iberian Market
Authors: Fernandes Renato , Soares Isabel
Published: July 2022

In this paper, for the data set of the Iberian Electricity Market for the period 1 January 2015 to 30 June 2019, 19 different models are considered from econometrics, statistics, and artificial intelligence to explain how electricity markets work. This survey allows us to obtain a more complete, critical view of the most cited models. The machine learning models appear to be very good at selecting the best explanatory variables for the price. They provide an interesting insight into how much the price depends on each variable under a nonlinear perspective. Notwithstanding, it might be necessary to make the results understandable. Both the autoregressive models and the linear regression models can provide clear explanations for each explanatory variable, with special attention given to GARCHX and LASSO regression, which provide a cleaner linear result by removing variables that have a minimal linear impact.