bluuebunny/crossref_metadata_2025 huggingface dataset:
Multimodality Imaging Evaluation to Detect Subtle Right Ventricular Involvement in Patients with Acute Myocarditis and Preserved Left Ventricular Ejection Fraction
Authors: Bonanni Michela , Angelini Gianmarco , Leo Laura Anna , Schlossbauer Susanne Anna , Bergamaschi Luca , Landi Antonio , Sangiorgi Giuseppe Massimo , Forleo Cinzia , Pasotti Elena , Pedrazzini Giovanni , Valgimigli Marco , Faletra Francesco F. , Guglielmo Marco , Pavon Anna Giulia
Published: June 2023

Background: Evaluation of the right ventricle (RV) in patients with acute myocarditis (MY) remains challenging with both 2D transthoracic echocardiography (TTE) and cardiovascular magnetic resonance (CMR). We examined the incremental diagnostic value of CMR feature tracking (FT) to evaluate RV involvement in patients with myocarditis. Methods: We enrolled 54 patients with myocarditis and preserved left ventricle (LV) ejection fraction (EF). The CMR protocol included T2-weighted images for edema detection and late gadolinium enhancement (LGE) images. Global longitudinal strain (GLS) of the left ventricle (LV) and RV free wall strain (CMR-FWS) were obtained with CMR-FT. We identified 34 patients (62%) with inferior and lateral segment (IL-MY) involvement and 20 (38%) noIL-MY in case of any other myocardial segment involved. Here, 20 individuals who underwent CMR for suspected cardiac disease, which was not confirmed thereafter, were considered as the control population. Results: TTE and CMR showed normal RV function in all patients without visible RV involvement at the LGE or T2-weighted sequences. At CMR, LV-GLS values were significantly lower in patients with MY compared to the control group (median −19.0% vs. −21.0%, p = 0.029). Overall, CMR RV-FWS was no different between MY patients and controls (median −21.2% vs. −23.2 %, p = 0.201) while a significant difference was found between RV FWS in IL-MY and noIL-MY (median −18.17% vs. −24.2%, p = 0.004). Conclusions: CMR-FT has the potential to unravel subclinical RV involvement in patients with acute myocarditis, specifically in those with inferior and lateral injuries that exhibit lower RV-FWS values. In this setting, RV deformation analysis at CMR may be effectively implemented for a comprehensive functional assessment.
A Jordanian Multidisciplinary Consensus Statement on the Management of Dyslipidemia
Authors: Al Mousa Eyas , Al-Azzam Sayer , Araydah Mohammad , Karasneh Reema , Ghnaimat Mohammad , Al-Makhamreh Hanna , Al Khawaldeh Abdelkarim , Ali Abu Al-Samen Muneer , Haddad Jihad , Al Najjar Said , Alsalaheen Abbadi Hatem , Hammoudeh Ayman J.
Published: June 2023

Atherosclerotic cardiovascular disease (ASCVD) is the primary contributor to global mortality rates, which significantly escalates healthcare expenditures. Risk factors for ASCVD (including dyslipidemia) frequently present in clusters rather than separately. Addressing these risk factors is crucial in the early initiation of a comprehensive management plan that involves both lifestyle modifications and pharmacotherapy to reduce the impact of ASCVD. A team of Jordanian professionals from various medical organizations and institutes took the initiative to create a set of guidelines for dyslipidemia screening and therapy. A detailed, comprehensive literature review was undertaken utilizing several databases and keywords. This consensus statement provides recommendations for dyslipidemia management in Jordanians on several issues including cardiovascular risk estimation, screening eligibility, risk categories, treatment goals, lifestyle changes, and statin and non-statin therapies. It is recommended that all Jordanian individuals aged 20 years old or older undergo lipid profile testing. This should be followed by determining the level of cardiovascular risk depending on the presence or absence of ASCVD and cardiovascular risk factors, eligibility for lipid-lowering therapy, and the target low-density cholesterol serum level to be achieved. In conclusion, prioritizing the management of dyslipidemia is of the utmost importance in improving public health and reducing the burden of cardiovascular diseases.
Placenta-on-a-Chip as an In Vitro Approach to Evaluate the Physiological and Structural Characteristics of the Human Placental Barrier upon Drug Exposure: A Systematic Review
Authors: Elzinga Femke A. , Khalili Behrad , Touw Daan J. , Prins Jelmer R. , Olinga Peter , Leuvenink Henri G. D. , van Goor Harry , Gordijn Sanne J. , Nagelkerke Anika , Mian Paola
Published: June 2023

Quantification of fetal drug exposure remains challenging since sampling from the placenta or fetus during pregnancy is too invasive. Currently existing in vivo (e.g., cord blood sampling) and ex vivo (e.g., placenta perfusion) models have inherent limitations. A placenta-on-a-chip model is a promising alternative. A systematic search was performed in PubMed on 2 February 2023, and Embase on 14 March 2023. Studies were included where placenta-on-a-chip was used to investigate placental physiology, placenta in different obstetric conditions, and/or fetal exposure to maternally administered drugs. Seventeen articles were included that used comparable approaches but different microfluidic devices and/or different cultured maternal and fetal cell lines. Of these studies, four quantified glucose transfer, four studies evaluated drug transport, three studies investigated nanoparticles, one study analyzed bacterial infection and five studies investigated preeclampsia. It was demonstrated that placenta-on-a-chip has the capacity to recapitulate the key characteristics of the human placental barrier. We aimed to identify knowledge gaps and provide the first steps towards an overview of current protocols for developing a placenta-on-a-chip, that facilitates comparison of results from different studies. Although models differ, they offer a promising approach for in vitro human placental and fetal drug studies under healthy and pathological conditions.
‘Status Quo’ on Different Aspects of Gender Distribution in Rheumatology in Germany—Results from a Nationwide Online Survey among Physicians
Authors: Ohrndorf Sarah , Krusche Martin , Baraliakos Xenofon , Feist Eugen , Gundelach Barbara , Haase Isabell , Hoyer Bimba Franziska , Kiltz Uta , Koehm Michaela , Voormann Anna Julia , Sewerin Philipp , Mucke Johanna
Published: June 2023

Objectives: Despite the increasing number of female medical students and fellows in Europe, women are still under-represented in higher academic careers and positions in medicine. The aim of this survey was to assess the ‘status quo’ on gender distribution among rheumatologists in Germany. Methods: A web-based anonymous survey (21 questions with multiple answers and free text) using QuestionPro® was distributed among rheumatologists in Germany via newsletters, social media and personal contact, including questions regarding hierarchical positions and work characteristics. Results: Among the total of 170 respondents (72% women, 28% men, 1% diverse), 48% were rheumatologists in training, 35% were trained rheumatologists and 7% were heads of rheumatology departments. Regarding the gender ratio at different hierarchical levels, 74% of respondents reported more men than women in leadership positions. Part-time work was possible in the departments of 86% of respondents, with more women working part-time (56%) compared to men (29%). Most respondents stated their impression that employees working part-time did not have the same career chances as full-time workers in their departments. In total, 66% agreed that activities to improve gender equity are necessary. The highest need was seen in reconciling work and family through, e.g., part-time models, flexible childcare options at work and a higher acceptance of part-time work in leadership positions. Conclusions: According to our results, a gender imbalance is prevalent among rheumatologists in Germany, with lower numbers of women evident at higher hierarchical levels. Traditional role assignments are still represented by a higher proportion of part-time work in women. The establishment of structural changes to achieve better gender equity is needed.
Oral Anticoagulants after Heart Transplantation—Comparison between Vitamin K Antagonists and Direct Oral Anticoagulants
Authors: Darche Fabrice F. , Fabricius Lisa C. , Helmschrott Matthias , Rahm Ann-Kathrin , Ehlermann Philipp , Bruckner Tom , Sommer Wiebke , Warnecke Gregor , Frey Norbert , Rivinius Rasmus
Published: June 2023

Aims: Patients after heart transplantation (HTX) often require oral anticoagulants (OACs) due to atrial arrhythmias or thromboembolic events but little is known about the post-transplant use of direct oral anticoagulants (DOACs). We investigated the frequency, indications, and complications of DOACs and vitamin K antagonists (VKAs) after HTX. Methods: We screened all adult patients for the use of post-transplant OACs who underwent HTX at Heidelberg Heart Center between 2000 and 2021. Patients were stratified by type of OAC (DOAC or VKA) and by DOAC agents (apixaban, dabigatran, edoxaban, or rivaroxaban). Indications for OACs comprised atrial fibrillation, atrial flutter, pulmonary embolism, upper and lower extremity deep vein thrombosis, as well as intracardiac thrombus. Results: A total of 115 of 459 HTX recipients (25.1%) required OACs, including 60 patients with DOACs (52.2%) and 55 patients with VKAs (47.8%). Concerning DOACs, 28 patients were treated with rivaroxaban (46.7%), 27 patients with apixaban (45.0%), and 5 patients with edoxaban (8.3%). We found no significant differences between both groups concerning demographics, immunosuppressive drugs, concomitant medications, indications for OACs, ischemic stroke, thromboembolic events, or OAC-related death. Patients with DOACs after HTX had a significantly lower one-year rate of overall bleeding complications (p = 0.002) and a significantly lower one-year rate of gastrointestinal hemorrhage (p = 0.011) compared to patients with VKAs after HTX in the Kaplan–Meier estimator. Conclusions: DOACs were comparable to VKAs concerning the risk of ischemic stroke, thromboembolic events, or OAC-related death but were associated with significantly fewer bleeding complications in HTX recipients.
Mid-Term Migration Behavior of an Uncemented Proximally Anchored Straight Stem—A Retrospective EBRA Migration Analysis
Authors: Blum Philipp , Neugebauer Johannes , Keiler Alexander , Putzer David , Watrinet Julius , Biermeier Sebastian , Dammerer Dietmar
Published: June 2023

Background: Aseptic loosening is one of the most-common causes of the failure of cementless stems. Einzel Bild Röntgen Analyse-Femoral Component Analysis (EBRA-FCA) allows the diagnosis of stem migration, which can be considered a factor in predicting implant survival. The current study aimed to present the migration behavior of a tapered proximally anchored straight stem. Methods: This retrospective study reviewed all consecutive patients who received a cementless CBC straight stem (Mathys AG, Bettlach, Switzerland) between 2005 and 2019. We analyzed the migration pattern using the EBRA-FCA software and reviewed their medical histories. In addition, periprosthetic radiolucency was rated according to the Gruen zones and femoral configuration according to Dorr. Results: A total of 333 stems in 332 patients (female 191; male 141) met our inclusion criteria. The mean age at surgery was 63 (range 21–87) years. Migration analysis by EBRA-FCA showed a mean subsidence of 1.6 mm at final follow-up at 96 months with a maximum noted mean subsidence of 2.0 mm at 72 and 84 months. Dorr Type A showed a tendency of less subsidence than did Dorr Type B and was statistically significant at 6 (p = 0.0396) and 72 months (p = 0.0127). The body mass index (BMI) and increased subsidence were not found to correlate (p > 0.05). For this cohort, the overall femoral revision-free rate was 95.2% and the revision-free rate for aseptic loosening was 99.1%. Conclusions: The results showed migration behavior in cementless stems with initial increased migration and subsequent secondary stabilization, suggesting an excellent long-term outcome. Stem migration of this tapered proximally anchored stem might be lower in Dorr Type A than in Dorr Type B femurs without being statistically significant at all time points.
Newly Developed Resorbable Magnesium Biomaterials for Orbital Floor Reconstruction in Caprine and Ovine Animal Models—A Prototype Design and Proof-of-Principle Study
Authors: Tomic Josip , Wiederstein-Grasser Iris , Schanbacher Monika , Weinberg Annelie Martina
Published: June 2023

Background: orbital floor fractures have not been reconstructed using magnesium biomaterials. Methods: To test technical feasibility, ex vivo caprine and ovine heads (n = 5) were used. Head tissues were harvested from pubescent animals (n = 5; mean age: 3.2 years; mean mass: 26.3 kg) and stored below 11 degrees for 7–10 days. All procedures were performed in a university animal resource facility. Two experienced maxillofacial surgeons performed orbital floor procedures in both orbits of all animals in a step-by-step preplanned dissection. A transconjunctival approach was chosen to repair the orbital floor with three different implants (i.e., magnesium implants; titanium mesh; and polydioxanone or PDO sheets). The position of each implant was evaluated by Cone-beam computed tomography (CBCT). Results: Axial, coronal, and sagittal plane images showed good positioning of the magnesium plates. The magnesium plates had a radiographic visibility similar to that of the PDO sheets but lower than that of the titanium mesh. Conclusions: The prototype design study showed a novel indication for magnesium biomaterials. Further testing of this new biomaterial may lead to the first resorbable biomaterial with good mechanical properties for extensive orbital wall defects.
Evaluation of the Safety and Gastrointestinal Migration of Guanidinylated Chitosan after Oral Administration to Rats
Authors: Khan Nowshin Farzana , Nakamura Hideaki , Izawa Hironori , Ifuku Shinsuke , Kadowaki Daisuke , Otagiri Masaki , Anraku Makoto
Published: June 2023

Arginine-rich membrane-permeable peptides (APPs) can be delivered to cells by forming complexes with various membrane-impermeable bioactive molecules such as proteins. We recently reported on the preparation of guanidinylated chitosan (GCS) that mimics arginine peptides, using chitosan, a naturally occurring cationic polysaccharide, and confirmed that it enhances protein permeability in an in vitro cell system. However, studies on the in vivo safety of GCS are not available. To address this, we evaluated the in vivo safety of GCS and its translocation into the gastrointestinal tract in rats after a single oral administration of an excessive dose (500 mg/kg) and observed changes in body weight, major organ weights, and organ tissue sections for periods of up to 2 weeks. The results indicated that GCS causes no deleterious effects. The results of an oral administration of rhodamine-labeled chitosan and an evaluation of its migration in the gastrointestinal tract suggested that the disappearance of rhodamine-labeled GCS from the body appeared to be slower than that of the non-dose group and pre-guanidinylated chitosan due to its mucoadhesive properties. In the future, we plan to investigate the use of GCS to improve absorption using Class III and IV drugs, which are poorly water-soluble as well as poorly membrane-permeable.
The Concept of Scaffold-Guided Bone Regeneration for the Treatment of Long Bone Defects: Current Clinical Application and Future Perspective
Authors: Laubach Markus , Hildebrand Frank , Suresh Sinduja , Wagels Michael , Kobbe Philipp , Gilbert Fabian , Kneser Ulrich , Holzapfel Boris M. , Hutmacher Dietmar W.
Published: June 2023

The treatment of bone defects remains a challenging clinical problem with high reintervention rates, morbidity, and resulting significant healthcare costs. Surgical techniques are constantly evolving, but outcomes can be influenced by several parameters, including the patient’s age, comorbidities, systemic disorders, the anatomical location of the defect, and the surgeon’s preference and experience. The most used therapeutic modalities for the regeneration of long bone defects include distraction osteogenesis (bone transport), free vascularized fibular grafts, the Masquelet technique, allograft, and (arthroplasty with) mega-prostheses. Over the past 25 years, three-dimensional (3D) printing, a breakthrough layer-by-layer manufacturing technology that produces final parts directly from 3D model data, has taken off and transformed the treatment of bone defects by enabling personalized therapies with highly porous 3D-printed implants tailored to the patient. Therefore, to reduce the morbidities and complications associated with current treatment regimens, efforts have been made in translational research toward 3D-printed scaffolds to facilitate bone regeneration. Three-dimensional printed scaffolds should not only provide osteoconductive surfaces for cell attachment and subsequent bone formation but also provide physical support and containment of bone graft material during the regeneration process, enhancing bone ingrowth, while simultaneously, orthopaedic implants supply mechanical strength with rigid, stable external and/or internal fixation. In this perspective review, we focus on elaborating on the history of bone defect treatment methods and assessing current treatment approaches as well as recent developments, including existing evidence on the advantages and disadvantages of 3D-printed scaffolds for bone defect regeneration. Furthermore, it is evident that the regulatory framework and organization and financing of evidence-based clinical trials remains very complex, and new challenges for non-biodegradable and biodegradable 3D-printed scaffolds for bone regeneration are emerging that have not yet been sufficiently addressed, such as guideline development for specific surgical indications, clinically feasible design concepts for needed multicentre international preclinical and clinical trials, the current medico-legal status, and reimbursement. These challenges underscore the need for intensive exchange and open and honest debate among leaders in the field. This goal can be addressed in a well-planned and focused stakeholder workshop on the topic of patient-specific 3D-printed scaffolds for long bone defect regeneration, as proposed in this perspective review.
A Multi-Objective Optimization of the Anchor-Last Deployment of the Marine Submersible Buoy System Based on the Particle Swarm Optimization Algorithm
Authors: Chen Xiaohan , Liu Bing , Le Guigao
Published: June 2023

Marine submersible buoy systems hold significant value as critical equipment in marine science research. This study examines a marine submersible buoy system that includes an anchor block, mooring line, battery compartment, power supply cable, and submersible buoy. The anchor-last deployment method is a conventional strategy for deploying marine submersible systems. Initially, the other components are positioned on the sea surface, followed by the deployment of the anchor block from the ship’s deck. The anchor block will pull the battery compartment and submersible buoy into the water and eventually sink to the seabed. In this deployment process, ocean currents have a relatively large impact on the anchor block’s landing position. Increasing the weight of the anchor block will make the anchor block land on the seabed sooner, which can minimize the impact of ocean currents. However, an overabundance of weight can generate a significant strain on both the cables, potentially resulting in cable breakage. In order to find the parameters that can make the anchor block reach the seabed as soon as possible and ensure that the tension force of the cables does not exceed the maximum, a dynamic model of the deployment process is established based on computational fluid dynamics (CFD) and solved using the Runge–Kutta method of the fourth order. Particle swarm optimization is employed to optimize the key parameters. The penalty function is used to constrain the particle space. The findings indicate that the utilization of particle swarm optimization is efficacious for optimizing the parameters of submersible buoy systems for marine applications. Optimized parameters allow the anchor block to reach the seafloor quickly and the tension on the cables to not exceed the given value.
Incorporating Uncertainty Quantification for the Performance Improvement of Academic Recommenders
Authors: Zhu Jie , Novelo Luis Leon , Yaseen Ashraf
Published: June 2023

Deep learning is widely used in many real-life applications. Despite their remarkable performance accuracies, deep learning networks are often poorly calibrated, which could be harmful in risk-sensitive scenarios. Uncertainty quantification offers a way to evaluate the reliability and trustworthiness of deep-learning-based model predictions. In this work, we introduced uncertainty quantification to our virtual research assistant recommender platform through both Monte Carlo dropout ensemble techniques. We also proposed a new formula to incorporate the uncertainty estimates into our recommendation models. The experiments were carried out on two different components of the recommender platform (i.e., a BERT-based grant recommender and a temporal graph network (TGN)-based collaborator recommender) using real-life datasets. The recommendation results were compared in terms of both recommender metrics (AUC, AP, etc.) and the calibration/reliability metric (ECE). With uncertainty quantification, we were able to better understand the behavior of our regular recommender outputs; while our BERT-based grant recommender tends to be overconfident with its outputs, our TGN-based collaborator recommender tends to be underconfident in producing matching probabilities. Initial case studies also showed that our proposed model with uncertainty quantification adjustment from ensemble gave the best-calibrated results together with the desirable recommender performance.
Ecological Security Assessment Based on the “Importance–Sensitivity–Connectivity” Index and Pattern Construction: A Case Study of Xiliu Ditch in the Yellow River Basin, China
Authors: Xu Xinlei , Wang Siyuan , Yan Gege , He Xinyi
Published: June 2023

Resource, environmental, and ecological issues have become major constraints to the development of many regions. The Yellow River Basin is an important barrier for maintaining ecological security in northern China, but it has been impacted by problems such as severe soil erosion and declining biodiversity. The rational construction of ecological security patterns is important to enhance ecosystem functions and maintain regional ecological security. In this study, a comprehensive ecological security assessment system was constructed by selecting ecosystem service importance, ecological sensitivity, and landscape connectivity to assess the ecological security of Xiliu Ditch, an ecologically fragile region of the Inner Mongolia section of the Yellow River Basin in China. The assessment results showed significant spatial heterogeneity, with medium- and low-security value areas dominating, while high-security value areas accounted for only 18.7% of the study area. Seventeen ecological sources were identified from the high-security areas, which were mainly composed of grassland, woodland, and water bodies, most of which are distributed in the southern part of the study area. Twenty ecological corridors were selected by the minimum cumulative resistance model and gravity model and classified into 15 construction corridors and 5 potential corridors. Forty-six ecological nodes were defined, including twenty strategic points, nine potential strategic points, and seventeen break points. On this basis, we constructed an ecological security pattern of “two belts, three cores, six zones, multiple corridors and multiple nodes” and proposed corresponding ecological governance measures. This study explores the ecological security pattern at the small watershed scale, which helps to realize the fine management of the Xiliu Ditch basin and, on this basis, can provide scientific support for the ecological protection and sustainable development of the Yellow River basin. In addition, the ecological security assessment system proposed in this study can provide new ideas for the construction of ecological security patterns in similar ecologically fragile areas around the globe.
Foraging Practices and Sustainable Management of Wild Food Resources in Europe: A Systematic Review
Authors: Mina Giorgio , Scariot Valentina , Peira Giovanni , Lombardi Giampiero
Published: June 2023

Wild food gathering activities (i.e., foraging practices) played an important role in securing food in the past. Nowadays, these resources and the knowledge around their use are experiencing a process of erosion. This article aims to identify the factors explaining the abandonment or, on the other hand, the preservation of foraging practices in Europe. The second aim is to analyze how these practices contribute to the economic and social development of local communities and to the sustainability of land management. A systematic review of the literature on European foraging practices was performed to answer these research questions. Following this approach, 111 publications were selected and analyzed. The results highlight that the reasons for the abandonment of foraging practices are related to socio-economic changes as well as changes in the environment such as reduced availability and land-use change. On the other hand, heritagization processes of these resources, such as wild plants sold as traditional local products, in restaurants, or as eco-tourism experiences, are emerging. The sustainability of these practices has not been widely evaluated in the literature. Efficient management strategies of wild food resources could help foster all three dimensions of sustainability at the local level, as well as help preserve traditional knowledge. This systematic review thus contributes to highlighting the framework in which the sustainability of these practices should be assessed.
Effects of Temporal and Spatial Changes in Wetlands on Regional Carbon Storage in the Naoli River Basin, Sanjiang Plain, China
Authors: Dai Xilong , Wang Yue , Li Xinhang , Wang Kang , Zhou Jia , Ni Hongwei
Published: June 2023

The Naoli River (NLR) Basin is a crucial distribution area for wetlands in China. Investigating the link between land use changes and carbon storage in this basin is of significant importance for protecting regional ecosystems and promoting the sustainable development of the social economy. This paper uses long-term Landsat satellite images provided on the GEE (Google Earth Engine) platform and the random forest classification algorithm to create spatial distribution maps of land use in the NLR Basin from 1993 to 2022. The study analyzes the dynamic changes in wetlands in the basin over the past 30 years and employs the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model to explore the temporal and spatial evolution characteristics of carbon storage. The results reveal that the wetland area of the NLR Basin showed a downward trend from 1993 to 2022, with a total decrease of 1507.18 hm2 over 30 years. During this period, the carbon storage in the NLR Basin decreased, with a cumulative loss of 1.98 × 107 t, mainly due to the continuous reductions in wetland and forest land. Additionally, the change in carbon storage in the basin has a strong spatial and temporal relationship with the changes in land use/cover area. The total carbon storage is positively associated with the areas of wetland, forest land, and water bodies. The conversion of wetlands into any other land type results in the reduction in carbon storage. These findings can improve our understanding of the spatial and temporal dynamics of wetlands in the NLR Basin over the past 30 years and enable us to analyze the relationship between land use changes and regional carbon storage. The results of this study have great significance for protecting the wetland ecology and regional carbon balance in the NLR Basin.
Identification of Shaker Potassium Channel Family Members in Gossypium hirsutum L. and Characterization of GhKAT1aD
Authors: Wang Qianqian , Li Shuying , Li Fangjun , Tian Xiaoli , Li Zhaohu
Published: June 2023

K+ channels of the Shaker family have been shown to play crucial roles in K+ uptake and transport. Cotton (Gossypium hirsutum) is an important cash crop. In this study, the 24 Shaker family genes were identified in cotton. Phylogenetic analysis suggests that they were assigned to five clusters. Additionally, their chromosomal location, conserved motifs and gene structure were analyzed. The promoter of cotton Shaker K+ channel genes comprises drought-, low-temperature-, phytohormone-response elements, etc. As indicated by qRT-PCR (quantitative real-time PCR), cotton Shaker K+ channel genes responded to low K+ and NaCl, and especially dehydration stress, at the transcript level. Moreover, one of the Shaker K+ channel genes, GhKAT1aD, was characterized. This gene is localized in the plasma membrane and is predicted to contain six transmembrane segments. It restored the growth of the yeast mutant strain defective in K+ uptake, and silencing GhKAT1a via VIGS (virus-induced gene silencing) resulted in more severe symptoms of K+ deficiency in cotton leaves as well as a lower net K+ uptake rate. The results of this study showed the overall picture of the cotton Shaker K+ channel family regarding bioinformatics as well as the function of one of its members, which provide clues for future investigations of cotton K+ transport and molecular insights for breeding K+-efficient cotton varieties.
Ultrasensitive Detection of Malachite Green Isothiocyanate Using Nanoporous Gold as SERS Substrate
Authors: Raj Deepti , Tayyaba Noor , De Vita Ginevra , Scaglione Federico , Rizzi Paola
Published: June 2023

In this article, a high-performance nanostructured substrate has been fabricated for the ultrasensitive detection of the organic pollutant, Malachite green isothiocyanate (MGITC), in aquatic systems via the Surface Enhanced Raman Spectroscopy (SERS) technique. The chemical dealloying approach has been used to synthesize a three-dimensional nanoporous gold substrate (NPG) consisting of pores and multigrained ligament structures along thickness. The formation of the framework in NPG-5h has been confirmed by SEM with an average ligament size of 65 nm at the narrower neck. Remarkable SERS performance has been achieved by utilizing the NPG-5h substrate for the detection of MGITC, showing a signal enhancement of 7.9 × 109. The SERS substrate also demonstrated an impressively low-detection limit of 10−16 M. The presence of numerous active sites, as well as plasmonic hotspots on the nanoporous surface, can be accredited to the signal amplification via the Localized Surface Plasmon Resonance (LSPR) phenomenon. As a result, SERS detection technology with the fabricated-NPG substrate not only proves to be a simple and effective approach for detecting malachite green but also provides a basis for in situ detection approach of toxic chemicals in aquatic ecosystems.
Iron, Cobalt, and Nickel Phthalocyanine Tri-Doped Electrospun Carbon Nanofibre-Based Catalyst for Rechargeable Zinc–Air Battery Air Electrode
Authors: Muuli Kaur , Kumar Rohit , Mooste Marek , Gudkova Viktoria , Treshchalov Alexey , Piirsoo Helle-Mai , Kikas Arvo , Aruväli Jaan , Kisand Vambola , Tamm Aile , Krumme Andres , Moni Prabu , Wilhelm Michaela , Tammeveski Kaido
Published: June 2023

The goal of achieving the large-scale production of zero-emission vehicles by 2035 will create high expectations for electric vehicle (EV) development and availability. Currently, a major problem is the lack of suitable batteries and battery materials in large quantities. The rechargeable zinc–air battery (RZAB) is a promising energy-storage technology for EVs due to the environmental friendliness and low production cost. Herein, iron, cobalt, and nickel phthalocyanine tri-doped electrospun carbon nanofibre-based (FeCoNi-CNF) catalyst material is presented as an affordable and promising alternative to Pt-group metal (PGM)-based catalyst. The FeCoNi-CNF-coated glassy carbon electrode showed an oxygen reduction reaction/oxygen evolution reaction reversibility of 0.89 V in 0.1 M KOH solution. In RZAB, the maximum discharge power density (Pmax) of 120 mW cm−2 was obtained with FeCoNi-CNF, which is 86% of the Pmax measured with the PGM-based catalyst. Furthermore, during the RZAB charge–discharge cycling, the FeCoNi-CNF air electrode was found to be superior to the commercial PGM electrocatalyst in terms of operational durability and at least two times higher total life-time.
Identification of Anisotropic Coefficients in the Non-Principal Axis Directions of Tubular Materials Using Hole Bulging Test
Authors: Lin Yanli , Wang Yifan , Su Yibo , Liu Junpeng , Chen Kelin , He Zhubin
Published: June 2023

We propose an experimental method to identify anisotropic coefficients in non-principal axis directions of thin-walled tubes. The method involves extracting specimens from the parent tubes and machining a hole in the axial center. The specimens are then inserted into a tube without a hole. The inner diameter of the specimen is theoretically equal to the outer diameter of the inner tube. The double-layer tube undergoes free bulging under internal pressure in our self-developed experimental equipment, with the hole on the specimen expanding simultaneously. The stress states around the hole are uniaxial, and the hole deformation can reflect the anisotropic plastic flow characteristics of the tube. Furthermore, based on the information obtained from the proposed experimental method, a hybrid numerical–experimental method was used to identify the anisotropic coefficients of tubes. Through FE simulations, the relationships between the thickness, stress, and strain states around the hole, the hole shape, and anisotropic coefficients of non-principal axis directions are revealed, and the factors that affect the hole deformation are analyzed. Finally, the hole bulging experiments and FE simulations of AA6061-O extruded tube were conducted, and modeled with Hill48 and calibrated by uniaxial tensile and hoop tensile tests. Its in-plane anisotropy coefficients in any direction are given for the first time which first increase and then decrease from 0° to 90°, reaching a maximum of 1.13 in 60° and a minimum of 0.69 in 0°. This work can provide the key experimental data for establishing an accurate anisotropic plastic constitutive model of thin-walled tubes.
Porous Mullite Ceramic Modification with Nano-WO3
Authors: Mahnicka-Goremikina Ludmila , Svinka Ruta , Svinka Visvaldis , Goremikins Vadims , Ilic Svetlana , Grase Liga , Juhnevica Inna , Rundans Maris , Eiduks Toms Valdemars , Pludons Arturs
Published: June 2023

Mullite and mullite–alumina ceramics materials with dominance of the mullite phase are used in different areas of technology and materials science. Porous mullite ceramics materials can be used simultaneously as refractory heat insulators and also as materials for constructional elements. The purpose of this work was to investigate the WO3 nanoparticle influence on the evolution of the aluminum tungstate and zircon crystalline phases in mullite ceramics due to stabilization effects caused by different microsize ZrO2 and WO3. The use of nano-WO3 prevented the dissociation of zircon in the ceramic samples with magnesia-stabilized zirconia (MSZ), increased porosity by approximately 60 ± 1%, increased the intensity of the aluminum tungstate phase, decreased bulk density by approximately 1.32 ± 0.01 g/cm3, and increased thermal shock resistance by ensuring a loss of less than 5% of the elastic modulus after 10 cycles of thermal shock.
Producing Metal Powder from Machining Chips Using Ball Milling Process: A Review
Authors: Wei Leong , Abd Rahim Shayfull , Al Bakri Abdullah Mohd , Yin Allice , Ghazali Mohd , Omar Mohd , Nemeș Ovidiu , Sandu Andrei , Vizureanu Petrica , Abdellah Abdellah
Published: June 2023

In the pursuit of achieving zero emissions, exploring the concept of recycling metal waste from industries and workshops (i.e., waste-free) is essential. This is because metal recycling not only helps conserve natural resources but also requires less energy as compared to the production of new products from virgin raw materials. The use of metal scrap in rapid tooling (RT) for injection molding is an interesting and viable approach. Recycling methods enable the recovery of valuable metal powders from various sources, such as electronic, industrial, and automobile scrap. Mechanical alloying is a potential opportunity for sustainable powder production as it has the capability to convert various starting materials with different initial sizes into powder particles through the ball milling process. Nevertheless, parameter factors, such as the type of ball milling, ball-to-powder ratio (BPR), rotation speed, grinding period, size and shape of the milling media, and process control agent (PCA), can influence the quality and characteristics of the metal powders produced. Despite potential drawbacks and environmental impacts, this process can still be a valuable method for recycling metals into powders. Further research is required to optimize the process. Furthermore, ball milling has been widely used in various industries, including recycling and metal mold production, to improve product properties in an environmentally friendly way. This review found that ball milling is the best tool for reducing the particle size of recycled metal chips and creating new metal powders to enhance mechanical properties and novelty for mold additive manufacturing (MAM) applications. Therefore, it is necessary to conduct further research on various parameters associated with ball milling to optimize the process of converting recycled copper chips into powder. This research will assist in attaining the highest level of efficiency and effectiveness in particle size reduction and powder quality. Lastly, this review also presents potential avenues for future research by exploring the application of RT in the ball milling technique.
Additive Manufacturing of Advanced Ceramics Using Preceramic Polymers
Authors: Han Jinchen , Liu Chang , Bradford-Vialva Robyn L. , Klosterman Donald A. , Cao Li
Published: June 2023

Ceramic materials are used in various industrial applications, as they possess exceptional physical, chemical, thermal, mechanical, electrical, magnetic, and optical properties. Ceramic structural components, especially those with highly complex structures and shapes, are difficult to fabricate with conventional methods, such as sintering and hot isostatic pressing (HIP). The use of preceramic polymers has many advantages, such as excellent processibility, easy shape change, and tailorable composition for fabricating high-performance ceramic components. Additive manufacturing (AM) is an evolving manufacturing technique that can be used to construct complex and intricate structural components. Integrating polymer-derived ceramics and AM techniques has drawn significant attention, as it overcomes the limitations and challenges of conventional fabrication approaches. This review discusses the current research that used AM technologies to fabricate ceramic articles from preceramic feedstock materials, and it demonstrates that AM processes are effective and versatile approaches for fabricating ceramic components. The future of producing ceramics using preceramic feedstock materials for AM processes is also discussed at the end.
Engineering the Quaternary Hydrotalcite-Derived Ce-Promoted Ni-Based Catalysts for Enhanced Low-Temperature CO2 Hydrogenation into Methane
Authors: Peng Yuxin , Xiao Xin , Song Lei , Wang Ning , Chu Wei
Published: June 2023

Ce-promoted NiMgAl mixed-oxide (NiCex-C, x = 0, 1, 5, 10) catalysts were prepared from the quaternary hydrotalcite precursors for CO2 hydrogenation to methane. By engineering the Ce contents, NiCe5-C showed its prior catalytic performance in low-temperature CO2 hydrogenation, being about three times higher than that of the Ce-free NiCe0-C catalyst (turnover frequency of NiCe5-C and NiCe0-C: 11.9 h−1 vs. 3.9 h−1 @ 225 °C). With extensive characterization, it was found that Ce dopants promoted the reduction of NiO by adjusting the interaction between Ni and Mg(Ce)AlOx support. The highest ratio of surface Ni0/(Ni2+ + Ni0) was obtained over NiCe5-C. Meanwhile, the surface basicity was tailored with Ce dopants. The strongest medium-strength basicity and highest capacity of CO2 adsorption was achieved on NiCe5-C with 5 wt.% Ce content. The TOF tests indicated a good correlation with medium-strength basicity over the NiCex-C samples. The results showed that the high medium-strength and Ce-promoted surface Ni0 species endows the enhanced low-temperature catalytic performance in CO2 hydrogenation to methane.
Study of Biomass Composite Workpiece Support Structure Based on Selective Laser Sintering Technology
Authors: Sun Tianai , Guo Yanling , Li Jian , Guo Yifan , Zhang Xinyue , Wang Yangwei
Published: June 2023

When using selective laser sintering to print parts with thin-walled structures, the thermal action of the laser can cause thermal stresses that lead to plastic deformation, resulting in large warpage and dimensional deviations. To address this issue, this study proposes a bottom support method for selective laser sintering. The impact of lattice-type, concentric-type, and cross-type support structures with varying filling densities and thicknesses on the suppression of warpage and dimensional errors was investigated. The optimal process parameters for each support structure were then determined through optimization. The findings of this study demonstrated a reduction in Z-axis dimensional errors of the workpiece following the addition of supports. The reduction amounted to 33.809%, 86.160%, and 66.214%, respectively, compared to the original workpiece. Moreover, the corresponding warpage was reduced by 35.673%, 46.189%, and 46.059% for each respective case, showcasing an improvement in the printing precision. Therefore, the bottom support effectively reduces dimensional and shape errors in thin-walled parts printed by selective laser sintering. Specifically, the results obtained indicated that the concentric type of support is more effective in reducing dimensional errors and enhancing the shape accuracy of the printed workpiece. Conversely, the cross type of support demonstrated superior capabilities in minimizing the consumption of printing materials while still delivering satisfactory results. Thus, this study holds promise for contributing to the advancement of thin-walled part quality using selective laser sintering technology. This research can contribute to achieving greater accuracy in the fabrication of parts through 3D printing.
Application of the FEM Method to Modeling and Analysis of the Cold Thread Rolling Process—Part 1: Conditions for Ensuring a Plane State of Deformations
Authors: Kukiełka Krzysztof
Published: June 2023

The article concerns the application of the FEM method for the prediction of stress and deformation states in a workpiece during the thread rolling process (TR). The analysis covered a new kinematic variant of the TR process in which the basket of the head rotates and is torque-driven, while the workpiece is stationary and the head with the rollers moves axially relative to the workpiece. The TR process was considered as a geometrical and physical non-linear initial and boundary problem with non-linear, moving, and variable in time and space boundary conditions. The boundary conditions in the contact areas of the tool with the workpiece were unknown. An updated Lagrange (UL) description was used to describe the physical phenomena at a typical incremental step. The states of strain and strain rate were described by non-linear relationships without linearization. New discrete systems of motion and deformation equations of the object in the TR were introduced, which take into account the change in the stiffness of the system during the TR process. This equation was solved by the central differences method (explicit). The material parameters were estimated during tensile tests to determine the characteristics of the C45 steel, and a new semi-empirical method was used to determine the relationship yield stress, effective true strain, and effective true strain rate in the thread rolling process. A modified Cowper–Symonds material model was also used to model the displacement process of the wedge on an elastic/visco-plastic body reflecting the TR process. A non-linear dependency of material hardening module depending on strain and strain rate was introduced. To confirm the plane state of deformation and spatial state of stress, an experimental investigation was carried out. The computer models were validated, and a good convergence of the results was obtained. Applications in the ANSYS/LS-Dyna program were developed to simulate the TR process. The developed applications enable a comprehensive time analysis of the states of displacement, strain, and stress occurring in an object consisting of a workpiece (shaft) and a tool (roller) for the case of a plane strain state and a spatial stress state. Exemplary results of numerical analyzes are presented to explain the influence of the friction coefficient on the condition of the thread quality, and the state of deformations and stresses were shown.
Characteristics of Adsorption/Desorption Process on Dolomite Adsorbent in the Copper(II) Removal from Aqueous Solutions
Authors: Sočo Eleonora , Domoń Andżelika , Papciak Dorota , Michel Magdalena M. , Pająk Dariusz , Cieniek Bogumił , Azizi Mostafa
Published: June 2023

The removal of hazardous heavy metals that have been released into the environment due to industrial activities has become an important issue in recent years. The presented study concerned the removal of copper(II) ions from aqueous solutions using dolomites. Dolomite is a very attractive adsorbent due to its wide availability, low cost, good adsorption, and environmental compatibility. The paper describes the properties of D-I and D-II dolomites from two different open-cast mines in Poland. The properties of natural adsorbents were determined based on point of zero charges (PZC), elemental analysis of the adsorbent composition, FT-IR, XRD, and SEM spectra analysis. Depending on the initial concentration of the solution used, the adsorption efficiency of copper(II) ions was 58–80% for D-I and 80–97% for D-II. The adsorption mechanism in the case of D-II dolomite was mainly based on ion exchange, while chemisorption dominated the D-I dolomite surface. Considering the possibility of the regeneration and reuse of the adsorbent, dolomite D-II is a better material (the desorption efficiency of copper(II) ions was 58–80%). The adsorption behavior of dolomites has been described using six adsorption isotherms. The best fit was obtained for the Redlich–Peterson, Jovanović, and Langmuir isotherms, indicating that monolayer adsorption occurred. The maximum adsorption capacity for copper(II) was 378 mg/g of D-I and 308 mg/g of D-II.