bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective Hydrogenation of 2-Methyl-3-butyn-2-ol in Microcapillary Reactor on Supported Intermetallic PdZn Catalyst, Effect of Support Doping on Stability and Kinetic Parameters
Authors: Okhlopkova Lyudmila , Prosvirin Igor , Kerzhentsev Mikhail , Ismagilov Zinfer
Published: December 2022

The development of active, selective, and stable multicrystalline catalytic coatings on the inner surface of microcapillary reactors addresses environmental problems of fine organic synthesis, in particular by reducing the large quantities of reagents and byproducts. Thin-film nanosized bimetallic catalysts based on mesoporous pure titania and doped with zirconia, ceria, and zinc oxide, for use in microreactors, were developed, and the regularities of their formation were studied. The efficiency of PdZn/TixM1−xO2±y (M = Ce, Zr, Zn) in the hydrogenation of 2-methyl-3-butyn 2-ol was studied with an emphasis on the stability of the catalyst during the reaction. The catalytic parameters depend on the adsorption properties and activity of PdZn and Pd(0) active centers. Under reaction conditions, resistance to the decomposition of PdZn is a factor that affects the stability of the catalyst. The zinc-doped coating proved to be the most selective and stable in the reaction of selective hydrogenation of acetylenic alcohols in a microcapillary reactor. This coating retained a high selectivity of 98.2% during long-term testing up to 168 h. Modification of the morphology and electronic structure of the active component, by doping titania with Ce and Zr, is accompanied by a decrease in stability.
Limestone Calcination Kinetics in Microfluidized Bed Thermogravimetric Analysis (MFB-TGA) for Calcium Looping
Authors: Li Dan , Wang Yang , Li Zhenshan
Published: December 2022

Limestone calcination is an important part of calcium looping (CaL) technology and is critical to the design and operation optimization of fluidized bed reactors. However, obtaining a method of measuring the fast calcination kinetics in a fluidizing environment with isothermal conditions is still a challenge in the field of calcium looping. We address this challenge in this work and develop a new method of obtaining limestone calcination kinetics by injecting limestone particles into the hot fluidizing sands in a microfluidized bed thermogravimetric analysis (MFB-TGA) with a mass measurement resolution of 1 mg. The calcination characteristics of limestone are investigated at different particle sizes (150–1250 μm), temperatures (750–920 °C), and CO2 concentrations (0–30 vol.%). The experimental data measured from MFB-TGA were analyzed using a detailed model including surface reaction and intraparticle and external diffusion. The results show that the kinetics of limestone calcination measured by MFB-TGA are faster than those measured via regular TGA. This particle-injecting method of MFB-TGA provides a new experimental idea for measuring fast calcination kinetics occurring inside fluidized bed reactors and provides guidance on the application of CaL technology.
Lipozyme® TL IM Biocatalyst for Castor Oil FAME and Triacetin Production by Interesterification: Activity, Stability, and Kinetics
Authors: Gómez-Calvo Alba , Gallardo M. Esther , Ladero Miguel
Published: December 2022

Global climate change and present geopolitical tensions call for novel, renewable, and, ideally, sustainable resources and processes that, in the end, will be integrated in the natural cycles of carbon and water, progressively replacing non-renewable feedstocks. In this context, the production of biofuels and, in consequence, of biodiesel plays a notable role. This work is focused on the production of fatty acid methyl esters (FAME) from castor oil, an abundant non-edible oil, using a sustainable technology approach based on industrial lipases and methyl acetate as a methylating reagent to reduce biocatalyst inactivation. We have selected a stable industrial enzyme preparation to determine its suitability for FAME production: Lipozyme® TL IM (an inexpensive lipase from Thermomyces lanuginosus immobilized by agglomeration in silica gel). Several operational variables affecting the enzyme activity have been studied: methanol excess (6:1 to 13:1), temperature (from 40 to 60 °C), and enzyme concentration (10 and 30% w/w). At all temperatures and reagent ratios, we have also tested the enzyme stability for six cycles, showing its low to negligible inactivation under operational conditions. Finally, a novel multivariable kinetic model has been proposed and fitted to experimental data obtained in a wide experimental range for the first time, showing that direct and reverse in-series reactions are present. We have estimated the values of the kinetic constants and their standard errors, and goodness-of-fit parameters, observing that the kinetic model fitted very reasonably to all retrieved experimental data at the same time.
Catalytic Efficiency of Primary α-Amino Amides as Multifunctional Organocatalysts in Recent Asymmetric Organic Transformations
Authors: Reddy Ummareddy Venkata Subba , Anusha Bheemreddy , Begum Zubeda , Seki Chigusa , Okuyama Yuko , Tokiwa Michio , Tokiwa Suguru , Takeshita Mitsuhiro , Nakano Hiroto
Published: December 2022

Chiral primary α-amino amides, consisting of an adjacent enamine bonding site (Bronsted base site), a hydrogen bonding site (Bronsted acid site), and flexible bulky substituent groups to modify the steric factor, are proving to be extremely valuable bifunctional organocatalysts for a wide range of asymmetric organic transformations. Primary α-amino amides are less expensive alternatives to other primary amino organocatalysts, such as chiral diamines and cinchona-alkaloid-derived primary amines, as they are easy to synthesize, air-stable, and allow for the incorporation of a variety of functional groups. In recent years, we have demonstrated the catalytic use of simple primary α-amino amides and their derivatives as organocatalysts for the aldol reaction, Strecker reaction, Michael tandem reaction, allylation of aldehydes, reduction of N-Aryl mines, opening of epoxides, hydrosilylation, asymmetric hydrogen transfer, and N-specific nitrosobenzene reaction with aldehydes.
Porphyromonas gingivalis-Derived Lipopolysaccharide Promotes Glioma Cell Proliferation and Migration via Activating Akt Signaling Pathways
Authors: Gao Zeyuan , Weng Xiuhong , Yu Donghu , Pan Zhiyong , Zhao Mingjuan , Cheng Bo , Li Zhiqiang
Published: December 2022

Periodontitis is significantly associated with the risk of cancers in the lung and the digestive system. Emerging evidence shows a plausible link between periodontitis and several types of brain diseases. However, the association between periodontal infection and glioma remains unclear. In the cultured GL261 glioma cells, P. gingivalis lipopolysaccharide (LPS) significantly promoted cell proliferation at concentrations ranging from 10 to 1000 ng/mL. It promoted cell migration at a higher concentration (100 and 1000 ng/mL). Additionally, exposure to 100 ng/mL P. gingivalis LPS induced a significant increase in the expression of TNF-α, TGF-β, MMP2, and MMP9, as well as the phosphorylation level of Akt at Ser473. These changes induced by P. gingivalis LPS were significantly antagonized by the Akt inhibitor. Furthermore, a total of 48 patients with brain tumors were enrolled to investigate their periodontal status before receiving tumor management. Poor periodontal status [probing depth (PD) ≥ 6 mm and attachment loss (AL) >5 mm] was found in 42.9% (9/21) of patients with glioma, which was significantly higher than that in patients with benign tumors and the relevant data in the 4th National Oral Health Survey in China. The glioma patients with both AL > 5 mm and PD ≥ 6 mm had a higher ki-67 labeling index than those with AL ≤ 5 mm or PD < 6 mm. These findings support the association between periodontal infection and glioma progression.
Deciphering the Antifibrotic Property of Metformin
Authors: Septembre-Malaterre Axelle , Boina Chailas , Douanier Audrey , Gasque Philippe
Published: December 2022

Fibrosis is a chronic progressive and incurable disease leading to organ dysfunction. It is characterized by the accumulation of extracellular matrix proteins produced by mesenchymal stem cells (MSCs) differentiating into myofibroblasts. Given the complexity of its pathophysiology, the search for effective treatments for fibrosis is of paramount importance. Metformin, a structural dimethyl analog of the galegine guanide extracted from the “French Lilac” (Fabaceae Galega officinalis), is the most widely used antidiabetic drug, recently recognized for its antifibrotic effects through ill-characterized mechanisms. The in vitro model of TGF-β1-induced fibrosis in human primary pulmonary mesenchymal stem cells (HPMSCs), identified as CD248+ and CD90+ cells, was used to study the effects of metformin extracts. These effects were tested on the expression of canonical MSC differentiation markers, immune/inflammatory factors and antioxidative stress molecules using qRT-PCR (mRNA, miRNA), immunofluorescence and ELISA experiments. Interestingly, metformin is able to reduce/modulate the expression of different actors involved in fibrosis. Indeed, TGF-β1 effects were markedly attenuated by metformin, as evidenced by reduced expression of three collagen types and Acta2 mRNAs. Furthermore, metformin attenuated the effects of TGF-β1 on the expression of PDGF, VEGF, erythropoietin, calcitonin and profibrotic miRs, possibly by controlling the expression of several key TGF/Smad factors. The expression of four major fibrogenic MMPs was also reduced by metformin treatment. In addition, metformin controlled MSC differentiation into lipofibroblasts and osteoblasts and had the ability to restore redox balance via the Nox4/Nrf2, AMP and Pi3K pathways. Overall, these results show that metformin is a candidate molecule for antifibrotic effect and/or aiming to combat the development of chronic inflammatory diseases worldwide.
Cathepsins Trigger Cell Death and Regulate Radioresistance in Glioblastoma
Authors: Ding Xiaofeng , Zhang Chen , Chen Huajian , Ren Minghua , Liu Xiaodong
Published: December 2022

Treatment of glioblastoma (GBM) remains very challenging, and it is particularly important to find sensitive and specific molecular targets. In this work, we reveal the relationship between the expression of cathepsins and radioresistance in GBM. We analyzed cathepsins (cathepsin B, cathepsin D, cathepsin L, and cathepsin Z/X), which are highly associated with the radioresistance of GBM by regulating different types of cell death. Cathepsins could be potential targets for GBM treatment.
Mitochondria Drive Immune Responses in Critical Disease
Authors: Tiwari-Heckler Shilpa , Robson Simon C. , Longhi Maria Serena
Published: December 2022

Mitochondria engage in multiple cellular and extracellular signaling pathways ranging from metabolic control, antiviral and antibacterial host defense to the modulation of inflammatory responses following cellular damage and stress. The remarkable contributions of these organelles to innate and adaptive immunity, shape cell phenotype and modulate their functions during infection, after trauma and in the setting of inflammatory disease. We review the latest knowledge of mitochondrial biology and then discuss how these organelles may impact immune cells to drive aberrant immune responses in critical disease.
QTLs Related to Rice Callus Regeneration Ability: Localization and Effect Verification of qPRR3
Authors: Wu Jiemin , Chang Xinlei , Li Chuanhong , Zhang Zhaoyang , Zhang Jianguo , Yin Changxi , Ma Weihua , Chen Hao , Zhou Fei , Lin Yongjun
Published: December 2022

Mature and efficient tissue culture systems are already available for most japonica rice varieties (Oryza sativa ssp. geng). However, it remains challenging to regenerate the majority of indica rice varieties (Oryza sativa ssp. xian). In this study, quantitative trait loci (QTLs) associated with rice callus regeneration ability were identified based on the plant regeneration rate (PRR) and total green plant rate (TGPR) of the 93-11 × Nip recombinant inbred line population. Significant positive correlations were found between PRR and TGPR. A total of three QTLs (one for PRR and two for TGPR) were identified. qPRR3 (located on chromosome 3) was detected for both traits, which could explain 13.40% and 17.07% of the phenotypic variations of PRR and TGPR, respectively. Subsequently, the effect of qPRR3 on callus regeneration ability was validated by cryptographically tagged near-isogenic lines (NILs), and the QTL was narrowed to an interval of approximately 160 kb. The anatomical structure observation of the regenerated callus of the NILs revealed that qPRR3 can improve the callus regeneration ability by promoting the regeneration of shoots.
C-MYC Inhibited Ferroptosis and Promoted Immune Evasion in Ovarian Cancer Cells through NCOA4 Mediated Ferritin Autophagy
Authors: Jin Yanping , Qiu Jianping , Lu Xiufang , Li Guowei
Published: December 2022

Objective: We aimed to construct the ferritin autophagy regulatory network and illustrate its mechanism in ferroptosis, TME immunity and malignant phenotypes of ovarian cancer. Methods: First, we used Western blot assays and immunohistochemistry to detect the pathway expression in ovarian cancer samples (C-MYC, NCOA4). Then, we performed RIP and FISH analysis to verify the targeted binding of these factors after which we constructed ovarian cancer cell models and detected pathway regulator expression (NCOA4). Co-localization and Western blot assays were used to detect ferritin autophagy in different experimental groups. We selected corresponding kits to assess ROS contents in ovarian cancer cells. MMP was measured using flow cytometry and mitochondrial morphology was observed through TEM. Then, we chose Clone, EdU and Transwell to evaluate the proliferation and invasion abilities of ovarian cancer cells. We used Western blot assays to measure the DAMP content in ovarian cancer cell supernatants. Finally, we constructed tumor bearing models to study the effect of the C-MYC pathway on ovarian cancer tumorigenesis and TME immune infiltration in in vivo conditions. Results: Through pathway expression detection, we confirmed that C-MYC was obviously up-regulated and NCOA4 was obviously down-regulated in ovarian cancer samples, while their expression levels were closely related to the malignancy degree of ovarian cancer. RIP, FISH and cell model detection revealed that C-MYC could down-regulate NCOA4 expression through directly targeted binding with its mRNA. Ferritin autophagy and ferroptosis detection showed that C-MYC could inhibit ferroptosis through NCOA4-mediated ferritin autophagy, thus reducing ROS and inhibiting mitophagy in ovarian cancer cells. Cell function tests showed that C-MYC could promote the proliferation and invasion of ovarian cancer cells through the NCOA4 axis. The Western blot assay revealed that C-MYC could reduce HMGB1 release in ovarian cancer cells through the NCOA4 axis. In vivo experiments showed that C-MYC could promote tumorigenesis and immune evasion in ovarian cancer cells through inhibiting HMGB1 release induced by NCOA4-mediated ferroptosis. Conclusion: According to these results, we concluded that C-MYC could down-regulate NCOA4 expression through directly targeted binding, thus inhibiting ferroptosis and promoting malignant phenotype/immune evasion in ovarian cancer cells through inhibiting ferritin autophagy.
Transitioning to Sustainable Healthcare: Decarbonising Healthcare Clinics, a Literature Review
Authors: Duindam David
Published: December 2022

Background: Climate change is one of the largest threats to human health and well-being globally. The healthcare industry itself currently contributes to fueling the climate crisis with its emissions and material consumption. There has been much research on decarbonising hospitals ecological/carbon footprints but very limited study on ways to assist healthcare clinics in transitioning to a low-carbon healthcare system. Methods: A structured literature review was conducted, and the results analysed. Results: The literature review revealed four important areas to act upon to decarbonise a healthcare clinic most efficiently. These are: energy use, waste minimisation/management, the behaviors/attitudes of staff, and decarbonising the supply chain. Conclusions: The pooled literature reveals an evidence-based set of recommendations or guiding principles to decarbonise healthcare clinics the most effectively. To maximise operational effectiveness, how this is achieved will differ between clinics. Although this research is written with reference to Australia, these identified ini-tiatives are likely to be relatable to many other countries healthcare systems. Decarbonising health clinics will contribute to a sector-wide transition to more sustainable healthcare that will lead to improved environmental, social, economic and health outcomes.
The Needs of School Professionals for Eating Disorder Prevention in Australian Schools: A Mixed-Methods Survey
Authors: Pursey Kirrilly M. , Hart Melissa , Hure Alexis , Cheung Hei Man , Ong Liting , Burrows Tracy L. , Yager Zali
Published: December 2022

(1) Background: School professionals such as teachers and counsellors are uniquely positioned to facilitate discussion around disordered eating and body image; however, little is known about the needs of school professionals with respect to eating disorder prevention. This study aimed to explore the needs and perceptions of Australian school professionals regarding eating disorder prevention. (2) Methods: School professionals were recruited to a mixed-methods online cross-sectional survey. The survey assessed demographics and perceived needs and attitudes to eating disorder prevention. (3) Results: Most participants (92%) were willing to participate in eating disorder prevention; however, only 61% reported good knowledge and 41% reported feeling confident in implementing eating disorder prevention. Those who had received training in eating disorders (24%) reported higher confidence (p = 0.02) and knowledge (p = 0.04). Only 66% of respondents reported that all teachers should be involved in eating disorder prevention while barriers including workload, knowledge, and resources were commonly highlighted. Fewer respondents working in primary school settings reported the need for prevention approaches (p = 0.046). (4) Conclusions: Despite a willingness to be involved in the prevention of eating disorders, there are inconsistencies in attitudes regarding the role of school professionals in eating disorder prevention. The findings of this study reinforce that understanding professional roles, school settings, and personal attitudes is critical in the development of more efficacious school professional training and prevention interventions.
Gait Alterations in Two Young Siblings with Progressive Pseudorheumatoid Dysplasia
Authors: Sassi Silvia , Faccioli Silvia , Farella Giuseppina Mariagrazia , Tedeschi Roberto , Garavelli Livia , Benedetti Maria Grazia
Published: December 2022

Progressive pseudorheumatoid dysplasia (PPRD) is an autosomal recessive inherited skeletal dysplasia characterized by progressive non-inflammatory arthropathy affecting primarily the articular cartilage. Currently, little is known about the functional musculoskeletal aspects of these patients. In particular, an abnormal gait pattern has been described, without a clear hypothesis of the underlying causes in terms of muscular activity. This study presents the case of two siblings, 4 and 9 years old, a boy and a girl, respectively, suffering from PPRD at different stages of the disease. In addition to the clinical assessment, an instrumental gait analysis was performed. Swelling of the interphalangeal finger joints and fatigue were present in both cases. Gait abnormalities consisted of a relevant reduction in the ankle plantarflexion in the terminal phase of the gait cycle, associated with reduced gastrocnemius EMG activity and increased activity of the tibialis anterior, resulting in overloading at the initial peak of ground reaction forces. Gait anomalies observed were similar in both siblings with PPRD, although at different ages, and confirm walking patterns previously described in the literature. The calf muscle strength deficit and reduced activity during the stance phase of gait present in these two siblings indicate the typical absence of the propulsive phase. A stomping gait pattern, with the foot striking the ground hard on each step, was originally described. Further neurophysiological investigations are required to determine the origin of muscle weakness.
Twenty-Year Retrospective Study of Post-Enucleation Chemotherapy in High-Risk Patients with Unilateral Retinoblastoma
Authors: Sunwoo Yoon , Choi Jung Yoon , Park Hyun Jin , Kim Bo Kyung , Hong Kyung Taek , Khwarg Sang In , Koh Jaemoon , Park Sung-Hye , Jo Dong Hyun , Kim Jeong Hun , Cheon Jung-Eun , Kang Hyoung Jin
Published: December 2022

Primary enucleation is a life-saving treatment for advanced intraocular retinoblastoma, particularly in patients with poor visual potential and functional contralateral eyes. This single-center study presents the treatment outcomes of patients with unilateral retinoblastoma who received primary enucleation and adjuvant chemotherapy with cyclophosphamide, vincristine, doxorubicin, and intrathecal methotrexate (CVDM) between 2000 and 2020. Twenty patients were enrolled in the study. The median age at diagnosis was 26 months (range, 1–45). Eighteen patients (90%) were in group E and two (10%) were in group D, according to the intraocular classification of retinoblastoma guidelines. Excluding one patient with an inadequate specimen, 19 patients (95%) had optic nerve involvement (ONI) at least up to the lamina cribrosa. Eight patients (40%) had choroidal invasion in addition to ONI. Two patients (10%) were surgical resection margin positive. The overall and event-free survival rates were 100% and 95%, respectively, for a median follow-up duration of 102.24 months (range 24.2–202.9). There were no relapses or deaths due to any cause, but one patient developed secondary rhabdomyosarcoma 99.6 months after chemotherapy. Treatment was well tolerated, with minimal hematotoxicity and hepatotoxicity. CVDM as a post-enucleation chemotherapy for advanced intraocular retinoblastoma has excellent outcomes with tolerable toxicity. However, in line with updated treatment trends, further risk stratification and lowering the treatment intensity should be considered. Continued long-term follow-up is required to further determine late effects.
Ultrasound Imaging-Based Methods for Assessing Biological Maturity during Adolescence and Possible Application in Youth Sport: A Scoping Review
Authors: Rüeger Eva , Hutmacher Nicole , Eichelberger Patric , Löcherbach Claus , Albrecht Silvia , Romann Michael
Published: December 2022

Bone maturity is an indicator for estimating the biological maturity of an individual. During adolescence, individuals show heterogeneous growth rates, and thus, differences in biological maturity should be considered in talent identification and development. Radiography of the left hand and wrist is considered the gold standard of biological maturity estimation. The use of ultrasound imaging (US) may be advantageous; however, its validity and reliability are under discussion. The aims of this scoping review are (1) to summarize the different methods for estimating biological maturity by US imaging in adolescents, (2) to obtain an overview of the level of validity and reliability of the methods, and (3) to point out the practicability and usefulness of ultrasound imaging in the field of youth sports. The search included articles published up to November 2022. The inclusion criteria stipulated that participants had to fall within the age range of 8 to 23 years and be free of bone disease and fractures in the region of interest. Nine body regions were investigated, while the hand and wrist were most commonly analyzed. US assessment methods were usually based on the estimation of a bone maturity stage, rather than a decimal bone age. Furthermore, 70% of the assessments were evaluated as applicable, 10% expressed restraint about implementation, and 20% were evaluated as not applicable. When tested, inter- and intra-rater reliability was high to excellent. Despite the absence of ionization, low costs, fast assessment, and accessibility, none of the US assessments could be referred to as a gold standard. If further development succeeds, its application has the potential to incorporate biological age into selection processes. This would allow for more equal opportunities in talent selection and thus make talent development fairer and more efficient.
Evaluation of Dysphagia and Inhalation Risk in Neurologically Impaired Children Using Esophageal High-Resolution Manometry with Swallowing Analysis
Authors: Caruso Anna Maria , Bommarito Denisia , Girgenti Vincenza , Amato Glenda , Figuccia Adele , Casuccio Alessandra , Ferlisi Annalisa , Genuardi Rosaria , La Fata Sabrina , Mattei Rosalia , Milazzo Mario Pietro Marcello , Di Pace Maria Rita
Published: December 2022

Background: Dysphagia in neurologically impaired children is associated with feeding difficulties, malnutrition and aspiration pneumonia. Esophageal high-resolution manometry (HRM) has been used in the diagnosis of motility disorders affecting the swallowing process. The aim of this study was to analyze swallowing functions in NI children by using HRM in order to establish swallow parameters identifying inhalation risk. Methods: Twenty-five NI children with cerebral palsy were submitted to esophageal HRM with UES analysis, comparing the results with non-NI children. The following parameters were evaluated: maximum pressure and duration of contraction of the velopharynx (VP) and tongue base (TB), and maximal, minimal, resting pressure and relaxation duration of the upper esophageal sphincter (UES). Results: pVP max, pTB max, pUES max and resting pressure were lower, while p UES minimal was higher and relaxation duration was shorter in NI children vs. the control group. Predictive values of inhalation risk were evaluated. Conclusions: This study evaluates inhalation risk in NI children using HRM to study UES function. Our results confirm the alterations described in NI children: insufficient contraction and clearing force for bolus transmission through the pharynx and incomplete UES relaxation can predispose to pharyngeal residues and inhalation independently of swallowing because of lower values of UES resting.
HIV Status Disclosure to Adolescents Who Are Perinatally Infected in Rustenburg Sub District Northwest Province
Authors: Khangale Happy Maybe Maambiwa , Raliphaswa Ndidzulafhi Selina , Tshililo Azwidihwi Rose
Published: December 2022

Acquired Immune Deficiency Syndrome (AIDS) is a viral disease caused by Human Immunodeficiency Virus (HIV) which affects the immune system of human body. This study sought to explore how adolescents with perinatal HIV infection learn about their status as well as investigate their preferences about the disclosure process. A qualitative exploratory, descriptive, and contextual research design was used to explore the disclosure of an HIV-positive status among adolescents on antiretroviral therapy. Nonprobability purposive sampling was used to select the healthcare facilities, and adolescents were chosen using convenience sampling. In-depth individual interviews were used to collect data from the participants until data saturation was reached. Collected data were analysed using Tesch’s eight steps. The results of the study revealed that adolescents have been on ART (antiretroviral therapy) without the knowledge of their own status but taking ART. Delayed disclosure of an HIV-positive status to adolescents lead to adolescent not adhering to ART and wondering why they are on treatment while other adolescents are not. The study further revealed that parents and caregivers struggle to disclose an HIV-positive status of their children, leading them to lie about what the treatment is for, for example, that it is a treatment for cough.
Intra-Abdominal Hypertension and Compartment Syndrome after Pediatric Liver Transplantation: Incidence, Risk Factors and Outcome
Authors: Junge Norman , Artmann Annika , Richter Nicolas , Vondran Florian W. R. , Böthig Dietmar , Sasse Michael , Köditz Harald , Baumann Ulrich , Beerbaum Philipp , Kaussen Torsten
Published: December 2022

In pediatric liver transplantation (pLT), the risk for the manifestation and relevance of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) is high. This observational study aimed to evaluate the incidence, relevance and risk factors for IAH and ACS by monitoring the intra-abdominal pressure (IAP), macro- and microcirculation (near-infrared spectroscopy (NIRS)), clinical and laboratory status and outcomes of 27 patients (16 female) after pLT (median age at pLT 35 months). Of the patients, 85% developed an elevated IAP, most of them mild. However, 17% achieved IAH° 3, 13% achieved IAH° 4 and 63% developed ACS. A multiple linear regression analysis identified aortal hepatic artery anastomosis and cold ischemia time (CIT) as risk factors for increased IAP and longer CIT and staged abdominal wall closure for ACS. ACS patients had significantly longer mechanical ventilation (p = 0.004) and LOS-PICU (p = 0.003). No significant correlation between NIRS or biliary complications and IAH or ACS could be shown. IAH and ACS after pLT were frequent. NIRS or grade of IAH alone should not be used for monitoring. A longer CIT is an important risk factor for higher IAP and ACS. Therefore, approaches such as the ex vivo machine perfusion of donor organs, reducing CIT effects on them, have great potential. Our study provides important basics for studying such approaches.
Constructing Counting and Arithmetic Learning Trajectories for Kindergarteners: A Preliminary Investigation in Taiwan
Authors: Wu Chung-Chin
Published: December 2022

Mathematics learning trajectories (LTs) for students above elementary school level are widely investigated. Recently, LTs for kindergarteners have also attracted attention, but in those studies the LTs were based on Western samples, and it is unclear whether they also involved culture and gender differences. Therefore, the purposes of this study were twofold: (1) construct a counting and arithmetic LT based on an Eastern sample and (2) show its similarities and differences by gender. The constructed LT contains 13 hypothesized levels of mathematical concepts according to previous research, and 59 kindergarteners (26 boys and 33 girls) participated in this study and completed a counting and arithmetic test to examine empirically the theoretical LT. The results showed that empirically, there were eight and nine conceptual levels for boys and girls, respectively, and boys and girls mastered concepts in a similar order (basic arithmetic→basic counting→advanced counting→mediocre arithmetic→advanced arithmetic), with the first part differing from the hypothesized LT. Within this developmental progression, girls showed a different path from advanced counting to mediocre arithmetic. The findings show gender and culture differences for the LTs for kindergarteners, which contradicts most previous research based on Western samples.
Glomerular Filtration Rate Assessment in Children
Authors: Jančič Sonja Golob , Močnik Mirjam , Marčun Varda Nataša
Published: December 2022

Glomerular filtration rate (GFR) measurement is a key tool for determining the degree of chronic kidney disease. The assessment of GFR is even more challenging in children than in adults with more variables in the equation than race and sex. Monitoring the progress of the kidney disease can therefore be difficult as in the initial stages of a decline in kidney function, there are no clinical signs. Due to children’s growth and development, changes in muscle mass and growth impair GFR estimation based solely on serum creatinine values. More invasive methods of GFR measurement are more reliable, but techniques using ionising agents, requiring large volume blood samples or timed voiding, have limited application in children. This paper reviews the methods of measuring and determining glomerular filtration rate and kidney function in children.
Effect of Intensified Training Camp on Psychometric Status, Mood State, and Hematological Markers in Youth Soccer Players
Authors: Selmi Okba , Levitt Danielle E. , Ouergui Ibrahim , Aydi Bilel , Bouassida Anissa , Weiss Katja , Knechtle Beat
Published: December 2022

During training camps, training load is purposefully intensified. Intensified training loads (TL) are associated with psychological variations, increased fatigue, insufficient recovery, decreased muscular performance, and biological changes in adult athletes, but whether these changes occur during training camps in youth athletes has not been established. The aim of this study was to assess changes in psychometric status, vertical jump performance (i.e., height), and hematological markers before and after an intensive training camp in youth soccer players. In this case, 15male youth soccer players (mean ± SD: age: 14.8 ± 0.4 years; height: 172.0 ± 6.9 cm, body mass: 60.8 ± 7.9 kg; training experience: 5.2 ± 0.7 years) completed a 2-week training program consisting of 1 week of moderate TL (MT) and 1 week of intensive training camp (TC). Rate of perceived exertion (RPE), TL, monotony, strain, and psychometric status (total quality of recovery (TQR) and well-being indices (sleep, stress, fatigue, and muscle soreness) were monitored before each first daily training session across two weeks. The profile of mood states (POMS), countermovement jump (CMJ) height, and blood markers (complete blood count, urea, and creatinine) were assessed before and after TC. TL (d = 5.39, large), monotony (d = 3.03, large), strain (d = 4.38, large), and well-being index (d = 7.5, large) scores increased and TQR (d = 4.6, large) decreased during TC. The TC increased tension, fatigue, and total mood disturbance and decreased vigor (all p <0.01). CMJ performance p < 0.01, d = 0.52, moderate), creatinine (p < 0.01, d = 1.29, large), and leukocyte concentration (p < 0.01, d = 1.4, large) and granulocyte concentration (p < 0.01, d = 1.93, large) increased after TC. Percentage of lymphocytes (p < 0.05, d = 1.17, large) and monocytes (p < 0.01, d = 1.05, large) decreased while the percentage of granulocytes (p < 0.05, d = 0.86, large) increased significantly. Well-being, quality of recovery, mood, granulocyte concentration, and creatinine were all altered during the week-long intensified training camp. These results may provide coaches with valuable information about psychometric status and physiological fatigue and recovery of youth soccer players to better prescribe and adjust training loads during intensive training periods.
Testing the Mystic School Mobile Application to Promote Active Commuting to School in Spanish Adolescents: The PACO Study
Authors: Saucedo-Araujo Romina Gisele , Huertas-Delgado Francisco Javier , Barranco-Ruiz Yaira María , Pérez-López Isaac José , Aznar-Laín Susana , Chillón Palma , Herrador-Colmenero Manuel
Published: December 2022

Active commuting to and/or from school (ACS) is an opportunity to increase daily physical activity (PA) levels in young people. Mobile-device interventions focused on promoting the practice of health-related PA can be more cost-effective than traditional interventions in this population. Objective: To analyze the adolescents’ opinion of the mobile application (app) Mystic School, which was designed to promote ACS in Spanish adolescents. Methods: A total of 44 students (14–15 years old) from Granada and Jaén participated in the test of the Mystic School app during two phases: phase 1 (n = 10) for 2 weeks and phase 2 (n = 34) for 1 month. Each phase included an app presentation, a follow-up, and focus group sessions. The qualitative analysis was carried out through NVivo software. Results: In phase 1, adolescents reported improvements in the design and functioning, such as the avatar movement, virtual steps utilities, and multiplayer function. These suggestions were included in phase 2. After phase 2, adolescents reported that it is important to add the possibility of playing without an Internet connection to the game, to include more competitive options, prizes, and to increase the difficulty of the levels. In both phases, problems with the step number counting remained. Conclusion: The Mystic School app can be a useful tool for the physical education teacher to integrate the content from this curriculum related to the promotion of PA, such as ACS.
Synthesis of a Hydroxyl-Containing Corrosion Inhibitor and Its Inhibitory Performance on N80 Steel in Hydrochloric Acid Solution
Authors: Sun Shoumin , Li Yang , Gao Kejing , Cheng Li , Yang Xue , Liao Ruiquan
Published: December 2022

In the process of petroleum exploitation, in order to effectively inhibit the corrosion damage of acid to metal equipment. Mannich base corrosion inhibitors are generally added to inhibit the corrosion damage of acid. In order to enhance the solubility of Mannich base corrosion inhibitor. This paper intends to introduce hydrophilic groups to enhance the solubility of the Mannich base corrosion inhibitor. In this paper, two efficient corrosion inhibitors 3-(2-hydroxyethylamino)-1-phenylpropan-1-one (MY1) and 3-(2-aminoethylamino)-1-phenylpropan-1-one (MY2), were synthesized based on the Mannich reaction, using formaldehyde, acetophenone and ethanolamine/ethylenediamine as reaction raw materials. The corrosion inhibition performance of the inhibitor on N80 steel in 15% (mass fraction) hydrochloric acid solution was studied by means of the static weight loss method, electrochemical test and optical contact angle analysis. It could be seen from the static weight loss method that the corrosion rate in the hydrochloric acid solution before and after adding 0.7% (mass fraction) corrosion inhibitor concentration decreased from 129.39 g·m−2·h−1 to 1.45 g·m−2·h−1 and 2.79 g·m−2·h−1, respectively. The corrosion inhibition rate could reach 98%, indicating that both inhibitors had good corrosion inhibition performance, and the corrosion inhibition effect of MY1 was better than that of MY2. It was found from the electrochemical tests that the two inhibitors were mixed corrosion inhibitors mainly inhibiting the anodic reaction, and both inhibitors belonged to spontaneous adsorption, and their adsorption behaviors followed the Langmuir adsorption isotherm. In addition, the surface of N80 steel was characterized by SEM, EDS elemental mapping and contact angle measurement. The results show that a dense hydrophobic film is formed on the surface of the steel sheet after the addition of a corrosion inhibitor, which prevents corrosion.
Study of the Tribological Properties of HVOF-Sprayed Ni-Based Coatings on Ti6Al4V Titanium Alloys
Authors: Du Pengcheng , Liu Chang , Hu Hongyun , Zhang Chunhui , Fan Mingzhen , Gao Mingchuan , Chen Tongzhou
Published: December 2022

In aviation, the relative sliding between titanium alloy components causes varying degrees of wear. This work aimed at reducing abrasion between titanium alloy parts and improving their service life. Three different Ni-based coatings, WC-10Ni, Ni45, and NiCr coatings, are sprayed on the surface of Ti6Al4V alloy by HVOF. Test results of the mechanical and tribological properties of such coatings show that the hardness of the Ni45 and NiCr coatings are 673 HV0.1 and 438 HV0.1, respectively, which are lower than that of the WC-10Ni coating. When subjected to a high load, the Ni45 and NiCr coatings suffer a cracking of flat particle interfaces due to the low hardness, which lowers the fracture toughness more than that of the WC-10Ni coating. The specific wear rates of the coatings gradually decrease with the increase in the coating hardness and fracture toughness. However, the cutting of Ti6Al4V by the WC-10Ni coating and the adhesion of the NiCr coating to Ti6Al4V result in severe wear loss of the Ti6Al4V friction pair. The moderately hard Ni45 coating has a weaker cutting and adhesion effect on Ti6Al4V than the WC-10Ni and NiCr coatings, respectively, and the Ti6Al4V friction pair has the lowest wear loss. This study is a viable scheme for the design of wear-resistant coatings on titanium alloy surfaces and for improving the tribological properties between titanium alloy components.
High-Temperature Solid Particle Erosion of Aerospace Components: Its Mitigation Using Advanced Nanostructured Coating Technologies
Authors: Bonu Venkataramana , Barshilia Harish C.
Published: December 2022

Solid particle erosion of gas turbine blades in the aerospace sector results in increased maintenance costs, high pollution, reduced engine efficiency, etc. Gas turbines in aircraft are usually operated at high temperatures. Based on the compressor stage, the temperature varies from 100–600°C, whereas turbine blades, after combustion, experience a very high temperature between 1000–1400 °C. So, a better understanding of temperature-dependent solid particle erosion is required to develop suitable solid particle erosion-resistant coatings for gas turbine blades. In this review, a detailed overview of the effect of temperature on the solid particle erosion process and different types of erosion-resistant coatings developed over the last four decades for compressor blades are discussed in detail. In the initial sections of the paper, solid particle erosion mechanisms, erosion by different erodent media, and the influence of erosion on gas turbine engines are discussed. Then, the erosion rate trend with increasing temperature for ductile and brittle materials, high-temperature erosion tests in a corrosive environment, and the role of oxidation and bonding nature in high-temperature erosion are examined. In most cases, the erosion rate of materials decreased with increasing temperature. After this, the evolution of erosion-resistant coatings over the last four decades that are first-generation (single-phase coatings), second-generation (metal/ceramic multilayer coatings), and third-generation (nanocomposite and nano-multilayer coatings) erosion-resistant coatings are reviewed in detail. The third-generation nano coatings were found to be superior to the first- and second-generation erosion-resistant coatings. Finally, some of the commercial or notable erosion-resistant coatings developed in the last decade are discussed. The paper concluded with the research gaps that need to be addressed to develop efficient erosion-resistant coatings.
Special Issue: Multi-Functional Nanostructured Sustainable Coatings
Authors: Kumar Kamal , Jain Arihan , Siddiquee Arshad Noor
Published: December 2022

The applications of surface coatings have been extensively explored in various technological fields, including the aeronautic and transport, tool and die, chemical and petroleum, nuclear, electronics, and biomedical industries [...]
Influence of Annealing on the Microstructure and Mechanical Properties of Ni-W/Boron Composite Coatings
Authors: Das Malay Kumar , Pinitpuwadol Waralee , Wonlopsiri Kohpong , Wangyao Panyawat , Qin Jiaqian
Published: December 2022

Ni-W/boron composite coatings are deposited from an ammonia citrate bath with a boron particle suspension. The effect of the boron incorporation into the Ni-W alloy coating and subsequent heat treatment of the deposits on the microstructure and properties of the Ni-W/boron coatings have been investigated. The boron particles can be uniformly dispersed in the Ni-W alloy, which can lead to an enhancement in the wear performance and hardness of the coatings. The XRD results show that a new Ni4W phase can be formed, especially at heat treatment temperatures beyond 400 °C. The grain size of the deposits is smaller than 10 nm with heat treatment temperatures lower than 600 °C and increases with the heat treatment temperature increasing. The higher temperature will significantly cause the grain coarsening (25.8 nm at 700 °C). Furthermore, the hardness and wear resistance increase with the formation of the Ni4W phase and the inverse Hall–Petch relationship at the lower heat treatment temperatures (<600 °C). While the grain coarsening causes the hardness of the deposits to decrease at the temperature of 700 °C.
Effect of Mo and C Additions on Eta Phase Evolution of WC-13Co Cemented Carbides
Authors: Li Xun , Zhang Xianwei , Zhang Junfei , Zhang Qiang , Ji Vincent , Liu Jinlong
Published: December 2022

The WC-13Co (wt.%) cemented carbide was prepared by simple pressureless sintering, and the influence of Mo and C additions on the eta evolution and mechanical properties was analyzed by XRD, SEM, EDS, XPS, and Vickers hardness tester. The results show that the addition of Mo has an important influence on the composition, size, and distribution of the eta phase and Mo2C phase. When the Mo content increases from 0 to 2.5%, the Mo-enriched eta phase grows abnormally and the area fraction of the eta phase significantly increases to 40%, leading to an obvious increase in hardness from 1232 HV30 to 1321 HV30, and a decrease in fracture toughness from 12.5 MPa·m1/2 to 9.8 MPa·m1/2. The addition of carbon black effectively inhibits the formation of the eta phase in the samples with 2.5% Mo. Moreover, adding Mo can suppress WC coarsening in a high-carbon content, which is different from the obvious growth of WC grains in a high-carbon environment in traditional research. Finally, the mechanism of eta phase evolution during the sintering process of WC-Co cemented carbides containing Mo is discussed systematically.
Principles of Building Digital Twins to Design Integrated Energy Systems
Authors: Stennikov Valery , Barakhtenko Evgeny , Sokolov Dmitry , Mayorov Gleb
Published: December 2022

The design of integrated energy systems (IESs) is a challenging task by reason of the highly complex configurations of these systems, the wide range of equipment used, and a diverse set of mathematical models and dedicated software employed to model it. The use of digital twins allows modeling in virtual space for various IES configurations. As a result, an optimal option of IES is obtained, which is implemented in the construction or expansion of a real-world IES. The paper proposes the principles of building digital twins for solving the IES design problems. The paper presents a new methodological approach developed by the authors to design an IES with the help of its digital twin. This approach includes the following components: the architecture of the software platform to create digital twins, a set of technologies and tools to implement the platform, methods to automatically construct a digital twin based on the Model-Driven Engineering concept, an algorithm to design an IES based on its digital twin, and principles to organize a computational process using a multi-agent approach. The results of the computational experiment using the software implementation of the IES digital twin components are presented for a test energy supply scheme.