bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Financial and Non-Financial Work Incentives on the Safety Behavior of Heavy Truck Drivers
Authors: Škerlič Sebastjan , Erčulj Vanja
Published: March 2021

The goal of the research is to determine how compensation affects the safety behavior of truck drivers and consequently the frequency of traffic accidents. For this purpose, a survey was conducted on a sample of 220 truck drivers in international road transport in the EU, where the results of the Structural Equation Model (SEM) show that in the current state of the transport sector, financial and non-financial incentives have a positive impact on the work and safety behavior of drivers. Financial incentives also have an impact on drivers’ increased perception of their driving ability, while moving violations continue to have a major impact on the number of accidents. The proposed improvements enable decision-makers at the highest level to adopt legal solutions to help manage the issues that have been affecting the industry from a work, social and safety point of view for the past several years. The results of the research therefore represent an important guideline for improvements to the legislature as well as in the systematization of truck driver compensation within companies.
Emotional Processing in Healthy Ageing, Mild Cognitive Impairment, and Alzheimer’s Disease
Authors: Cárdenas José , Blanca María J. , Carvajal Fernando , Rubio Sandra , Pedraza Carmen
Published: March 2021

Emotional processing, particularly facial expression recognition, is essential for social cognition, and dysfunction may be associated with poor cognitive health. In pathological ageing conditions, such as mild cognitive impairment (MCI) and Alzheimer’s disease (AD), in which cognitive impairments are present, disturbed emotional processing and difficulty with social interactions have been documented. However, it is unclear how pathological ageing affects emotional processing and human social behaviour. The aim of this study is to provide insight into how emotional processing is affected in MCI and AD and whether this capacity can constitute a differentiating factor allowing the preclinical diagnosis of both diseases. For this purpose, an ecological emotional battery adapted from five subsets of the Florida Affect Battery was used. Given that emotion may not be separated from cognition, the affect battery was divided into subtests according to cognitive demand, resulting in three blocks. Our results showed that individuals with MCI or AD had poorer performance on the emotional processing tasks, although with different patterns, than that of controls. Cognitive demand may be responsible for the execution patterns of different emotional processing tests. Tasks with moderate cognitive demand are the most sensitive for discriminating between two cognitive impairment entities. In summary, emotional processing tasks may aid in characterising the neurocognitive deficits in MCI or AD. Additionally, identifying these deficits may be useful for developing interventions that specifically target these emotional processing problems.
Approaches to Nutritional Screening in Patients with Coronavirus Disease 2019 (COVID-19)
Authors: Ali Amira Mohammed , Kunugi Hiroshi
Published: March 2021

Malnutrition is common among severe patients with coronavirus disease 2019 (COVID-19), mainly elderly adults and patients with comorbidities. It is also associated with atypical presentation of the disease. Despite the possible contribution of malnutrition to the acquisition and severity of COVID-19, it is not clear which nutritional screening measures may best diagnose malnutrition in these patients at early stages. This is of crucial importance given the urgency and rapid progression of the disease in vulnerable groups. Accordingly, this review examines the available literature for different nutritional screening approaches implemented among COVID-19 patients, with a special focus on elderly adults. After a literature search, we selected and scrutinized 14 studies assessing malnutrition among COVID-19 patients. The Nutrition Risk Screening 2002 (NRS-2002) has demonstrated superior sensitivity to other traditional screening measures. The controlling nutritional status (CONUT) score, which comprises serum albumin level, cholesterol level, and lymphocytes count, as well as a combined CONUT-lactate dehydrogenase-C-reactive protein score expressed a predictive capacity even superior to that of NRS-2002 (0.81% and 0.92% vs. 0.79%) in midlife and elder COVID-19 patients. Therefore, simple measures based on routinely conducted laboratory investigations such as the CONUT score may be timely, cheap, and valuable alternatives for identifying COVID-19 patients with high nutritional risk. Mini Nutritional Assessment (MNA) was the only measure used to detect residual malnutrition and high malnutrition risk in remitting patients—MNA scores correlated with hypoalbuminemia, hypercytokinemia, and weight loss. Older males with severe inflammation, gastrointestinal symptoms, and pre-existing comorbidities (diabetes, obesity, or hypertension) are more prone to malnutrition and subsequently poor COVID-19 prognosis both during the acute phase and during convalescence. Thus, they are in need of frequent nutritional monitoring and support while detecting and treating malnutrition in the general public might be necessary to increase resilience against COVID-19.
The Role of Adequate Resources, Community and Supportive Leadership in Creating Engaged Academics
Authors: Christensen Marit , Dawson Jeremy , Nielsen Karina
Published: March 2021

The vast majority of research in academia focuses on the adverse working conditions and poor wellbeing. The present paper presents a positive view on the factors that may promote work engagement in academia. Based on conservation of resources theory, we suggest that academic resources may be related to a social community at work, which in turn creates work engagement among academics. Having positive leadership in the form of fair leadership may be an important contextual factor ensuring that resources are shared fairly and openly. In a study of 1499 academics in Norwegian universities, we found that sufficient administrative resources to support teaching duties were positively related with work engagement, and that a sense of community mediated the relationship between academic resources for teaching and work engagement. These results propose that building academics’ social resources by providing them with the necessary resources to perform their jobs will buffer the impact of a leadership that is perceived to be unfair and help them to perform their work in a positive way. Our results carry important implications for how positive psychology may be used to support engaged workers in academia.
The Role of Chronic Inflammation in Polycystic Ovarian Syndrome—A Systematic Review and Meta-Analysis
Authors: Aboeldalyl Shaimaa , James Cathryn , Seyam Emaduldin , Ibrahim Emad Moussa , Shawki Hossam El-Din , Amer Saad
Published: March 2021

Although the current literature associates polycystic ovarian syndrome (PCOS) with chronic inflammation, the evidence for this link remains inconclusive and its causal nature remains unclear. The purpose of this systematic review was to assess the inflammatory status in PCOS women and to determine whether it is related to PCOS or to its associated adiposity. We searched electronic databases including PUBMED, EMBASE and MEDLINE, SCOPUS, DynaMed plus, TRIP, ScienceDirect and Cochrane Library, for studies investigating C-reactive protein (CRP) and other inflammatory makers in PCOS women versus healthy controls. Quality and risk of bias for selected studies were assessed using the modified Newcastle–Ottawa scale. CRP data were extracted and pooled using RevMan for calculation of the standardized mean difference (SMD) and 95% confidence interval (CI). Eighty-five eligible studies were included in the systematic review, of which 63 were included in the meta-analysis. Pooled analysis of the 63 studies revealed significantly higher circulating CRP in PCOS women (n = 4086) versus controls (n = 3120) (SMD 1.26, 95%CI, 0.99, 1.53). Sensitivity meta-analysis of 35 high quality studies including non-obese women showed significantly higher circulating CRP in PCOS women versus controls (SMD 1.80, 95%CI, 1.36, 2.25). In conclusion, circulating CRP is moderately elevated in PCOS women independent of obesity, which is indicative of low-grade chronic inflammation.
Is the ENaC Dysregulation in CF an Effect of Protein-Lipid Interaction in the Membranes?
Authors: Strandvik Birgitta
Published: March 2021

While approximately 2000 mutations have been discovered in the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR), only a small amount (about 10%) is associated with clinical cystic fibrosis (CF) disease. The discovery of the association between CFTR and the hyperactive epithelial sodium channel (ENaC) has raised the question of the influence of ENaC on the clinical CF phenotype. ENaC disturbance contributes to the pathological secretion, and overexpression of one ENaC subunit, the β-unit, can give a CF-like phenotype in mice with normal acting CFTR. The development of ENaC channel modulators is now in progress. Both CFTR and ENaC are located in the cell membrane and are influenced by its lipid configuration. Recent studies have emphasized the importance of the interaction of lipids and these proteins in the membranes. Linoleic acid deficiency is the most prevailing lipid abnormality in CF, and linoleic acid is an important constituent of membranes. The influence on sodium excretion by linoleic acid supplementation indicates that lipid-protein interaction is of importance for the clinical pathophysiology in CF. Further studies of this association can imply a simple clinical adjuvant in CF therapy.
Diabetes, Obesity, and Inflammation: Impact on Clinical and Radiographic Features of Breast Cancer
Authors: Miller Braden , Chalfant Hunter , Thomas Alexandra , Wellberg Elizabeth , Henson Christina , McNally Molly W. , Grizzle William E. , Jain Ajay , McNally Lacey R.
Published: March 2021

Obesity, diabetes, and inflammation increase the risk of breast cancer, the most common malignancy in women. One of the mainstays of breast cancer treatment and improving outcomes is early detection through imaging-based screening. There may be a role for individualized imaging strategies for patients with certain co-morbidities. Herein, we review the literature regarding the accuracy of conventional imaging modalities in obese and diabetic women, the potential role of anti-inflammatory agents to improve detection, and the novel molecular imaging techniques that may have a role for breast cancer screening in these patients. We demonstrate that with conventional imaging modalities, increased sensitivity often comes with a loss of specificity, resulting in unnecessary biopsies and overtreatment. Obese women have body size limitations that impair image quality, and diabetes increases the risk for dense breast tis-sue. Increased density is known to obscure the diagnosis of cancer on routine screening mammography. Novel molecu-lar imaging agents with targets such as estrogen receptor, human epidermal growth factor receptor 2 (HER2), pyrimi-dine analogues, and ligand-targeted receptor probes, among others, have potential to reduce false positive results. They can also improve detection rates with increased resolution and inform therapeutic decision making. These emerg-ing imaging techniques promise to improve breast cancer diagnosis in obese patients with diabetes who have dense breasts, but more work is needed to validate their clinical application.
Anti-Apoptotic Effect of Apelin in Human Placenta: Studies on BeWo Cells and Villous Explants from Third-Trimester Human Pregnancy
Authors: Mlyczyńska Ewa , Myszka Małgorzata , Kurowska Patrycja , Dawid Monika , Milewicz Tomasz , Bałajewicz-Nowak Marta , Kowalczyk Paweł , Rak Agnieszka
Published: March 2021

Previously, we demonstrated the expression of apelin and G-protein-coupled receptor APJ in human placenta cell lines as well as its direct action on placenta cell proliferation and endocrinology. The objective of this study was to examine the effect of apelin on placenta apoptosis in BeWo cells and villous explants from the human third trimester of pregnancy. The BeWo cells and villous explants were incubated with apelin (2 and 20 ng/mL) alone or with staurosporine for 24 to 72 h. First, we analysed the dose- and time-dependent effect of apelin on the expression of apoptotic factors on the mRNA level by real-time PCR and on the protein level using Western blot. Next, we checked caspase 3 and 7 activity by Caspase-Glo 3/7, DNA fragmentation by the Cell Death Detection ELISA kit and oxygen consumption by the MitoXpress-Xtra Oxygen Consumption assay. We found that apelin increased the expression of pro-survival and decreased proapoptotic factors on mRNA and protein levels in both BeWo cells and villous explants. Additionally, apelin inhibited caspase 3 and 7 activity and DNA fragmentation in staurosporine-induced apoptosis as also attenuated oxidative stress by increasing extracellular oxygen consumption. The antiapoptotic effect of apelin in BeWo cells was mediated by the APJ receptor and mitogen-activated protein kinase (ERK1/2/MAP3/1) and protein kinase B (AKT). The obtained results showed the antiapoptotic effect of apelin on trophoblast cells, suggesting its participation in the development of the placenta.
Machine Learning and Novel Biomarkers for the Diagnosis of Alzheimer’s Disease
Authors: Chang Chun-Hung , Lin Chieh-Hsin , Lane Hsien-Yuan
Published: March 2021

Background: Alzheimer’s disease (AD) is a complex and severe neurodegenerative disease that still lacks effective methods of diagnosis. The current diagnostic methods of AD rely on cognitive tests, imaging techniques and cerebrospinal fluid (CSF) levels of amyloid-β1-42 (Aβ42), total tau protein and hyperphosphorylated tau (p-tau). However, the available methods are expensive and relatively invasive. Artificial intelligence techniques like machine learning tools have being increasingly used in precision diagnosis. Methods: We conducted a meta-analysis to investigate the machine learning and novel biomarkers for the diagnosis of AD. Methods: We searched PubMed, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews for reviews and trials that investigated the machine learning and novel biomarkers in diagnosis of AD. Results: In additional to Aβ and tau-related biomarkers, biomarkers according to other mechanisms of AD pathology have been investigated. Neuronal injury biomarker includes neurofiliament light (NFL). Biomarkers about synaptic dysfunction and/or loss includes neurogranin, BACE1, synaptotagmin, SNAP-25, GAP-43, synaptophysin. Biomarkers about neuroinflammation includes sTREM2, and YKL-40. Besides, d-glutamate is one of coagonists at the NMDARs. Several machine learning algorithms including support vector machine, logistic regression, random forest, and naïve Bayes) to build an optimal predictive model to distinguish patients with AD from healthy controls. Conclusions: Our results revealed machine learning with novel biomarkers and multiple variables may increase the sensitivity and specificity in diagnosis of AD. Rapid and cost-effective HPLC for biomarkers and machine learning algorithms may assist physicians in diagnosing AD in outpatient clinics.
Design, Synthesis, and Evaluation of Novel 3-Carboranyl-1,8-Naphthalimide Derivatives as Potential Anticancer Agents
Authors: Rykowski Sebastian , Gurda-Woźna Dorota , Orlicka-Płocka Marta , Fedoruk-Wyszomirska Agnieszka , Giel-Pietraszuk Małgorzata , Wyszko Eliza , Kowalczyk Aleksandra , Stączek Paweł , Bak Andrzej , Kiliszek Agnieszka , Rypniewski Wojciech , Olejniczak Agnieszka B.
Published: March 2021

We synthesized a series of novel 3-carboranyl-1,8-naphthalimide derivatives, mitonafide and pinafide analogs, using click chemistry, reductive amination and amidation reactions and investigated their in vitro effects on cytotoxicity, cell death, cell cycle, and the production of reactive oxygen species in a HepG2 cancer cell line. The analyses showed that modified naphthalic anhydrides and naphthalimides bearing ortho- or meta-carboranes exhibited diversified activity. Naphthalimides were more cytotoxic than naphthalic anhydrides, with the highest IC50 value determined for compound 9 (3.10 µM). These compounds were capable of inducing cell cycle arrest at G0/G1 or G2M phase and promoting apoptosis, autophagy or ferroptosis. The most promising conjugate 35 caused strong apoptosis and induced ROS production, which was proven by the increased level of 2′-deoxy-8-oxoguanosine in DNA. The tested conjugates were found to be weak topoisomerase II inhibitors and classical DNA intercalators. Compounds 33, 34, and 36 fluorescently stained lysosomes in HepG2 cells. Additionally, we performed a similarity-based assessment of the property profile of the conjugates using the principal component analysis. The creation of an inhibitory profile and descriptor-based plane allowed forming a structure–activity landscape. Finally, a ligand-based comparative molecular field analysis was carried out to specify the (un)favorable structural modifications (pharmacophoric pattern) that are potentially important for the quantitative structure–activity relationship modeling of the carborane–naphthalimide conjugates.
Stress and Nasal Allergy: Corticotropin-Releasing Hormone Stimulates Mast Cell Degranulation and Proliferation in Human Nasal Mucosa
Authors: Yamanaka-Takaichi Mika , Mizukami Yukari , Sugawara Koji , Sunami Kishiko , Teranishi Yuichi , Kira Yukimi , Paus Ralf , Tsuruta Daisuke
Published: March 2021

Psychological stress exacerbates mast cell (MC)-dependent inflammation, including nasal allergy, but the underlying mechanisms are not thoroughly understood. Because the key stress-mediating neurohormone, corticotropin-releasing hormone (CRH), induces human skin MC degranulation, we hypothesized that CRH may be a key player in stress-aggravated nasal allergy. In the current study, we probed this hypothesis in human nasal mucosa MCs (hM-MCs) in situ using nasal polyp organ culture and tested whether CRH is required for murine M-MC activation by perceived stress in vivo. CRH stimulation significantly increased the number of hM-MCs, stimulated both their degranulation and proliferation ex vivo, and increased stem cell factor (SCF) expression in human nasal mucosa epithelium. CRH also sensitized hM-MCs to further CRH stimulation and promoted a pro-inflammatory hM-MC phenotype. The CRH-induced increase in hM-MCs was mitigated by co-administration of CRH receptor type 1 (CRH-R1)-specific antagonist antalarmin, CRH-R1 small interfering RNA (siRNA), or SCF-neutralizing antibody. In vivo, restraint stress significantly increased the number and degranulation of murine M-MCs compared with sham-stressed mice. This effect was mitigated by intranasal antalarmin. Our data suggest that CRH is a major activator of hM-MC in nasal mucosa, in part via promoting SCF production, and that CRH-R1 antagonists such as antalarmin are promising candidate therapeutics for nasal mucosa neuroinflammation induced by perceived stress.
Prominent Role of Histone Modifications in the Regulation of Tumor Metastasis
Authors: Markouli Mariam , Strepkos Dimitrios , Basdra Efthimia K. , Papavassiliou Athanasios G. , Piperi Christina
Published: March 2021

Tumor aggressiveness and progression is highly dependent on the process of metastasis, regulated by the coordinated interplay of genetic and epigenetic mechanisms. Metastasis involves several steps of epithelial to mesenchymal transition (EMT), anoikis resistance, intra- and extravasation, and new tissue colonization. EMT is considered as the most critical process allowing cancer cells to switch their epithelial characteristics and acquire mesenchymal properties. Emerging evidence demonstrates that epigenetics mechanisms, DNA methylation, histone modifications, and non-coding RNAs participate in the widespread changes of gene expression that characterize the metastatic phenotype. At the chromatin level, active and repressive histone post-translational modifications (PTM) in association with pleiotropic transcription factors regulate pivotal genes involved in the initiation of the EMT process as well as in intravasation and anoikis resistance, playing a central role in the progression of tumors. Herein, we discuss the main epigenetic mechanisms associated with the different steps of metastatic process, focusing in particular on the prominent role of histone modifications and the modifying enzymes that mediate transcriptional regulation of genes associated with tumor progression. We further discuss the development of novel treatment strategies targeting the reversibility of histone modifications and highlight their importance in the future of cancer therapy.
Pilot Study to Evaluate the Efficacy of Polynucleotide Sodium Compared to Sodium Hyaluronate and Crosslinked Sodium Hyaluronate in Patients with Knee Osteoarthritis
Authors: Kim Ji Yeong , Kim Yoo Na , Lee Yu Jung , Sim Sung Eun , Ko Yu Ri , Shim Jin Woo , Lee Ku Sang , Joo Mina , Park Hue Jung
Published: March 2021

Degenerative arthritis of the knee joint has become a major social problem worldwide due to population aging. There are several treatment options for knee osteoarthritis, and the intraarticular injection of sodium hyaluronate is commonly selected by many clinicians as a nonsurgical treatment. However, the efficacy of the treatment is controversial. In this pilot study, we aimed to compare polynucleotide sodium (Conjuran®) with sodium hyaluronate (Hyruan Plus®) and 1,4-butanediol diglycidyl ether-crosslinked sodium hyaluronate (Synovian®) in terms of analgesic efficacy after intraarticular injection in patients with knee osteoarthritis. One of the three intraarticular agents was selected according to what agents were available for outpatients when each patient was enrolled in the study. The 15 enrolled patients were subdivided into 3 groups of 5 patients each. Three injections were performed under ultrasound guidance at a 1-week intervals over a total of 3 weeks. The visual analog scale (VAS) score, the Korean version of the Western Ontario and McMaster Universities Arthritis Index (K-WOMAC), the EuroQol five-dimension scale (EQ-5D) score, and the Korean version of the painDETECT Questionnaire (K-PDQ) score were evaluated before injection and at 1, 2, and 6 weeks after the start of the treatment protocol. The primary endpoint was the change in weight-bearing pain at 4 weeks after the last injection. Secondary endpoints included pain at rest and during walking and the K-WOMAC, EQ-5D, and K-PDQ scores. Weight-bearing pain decreased significantly more from pretreatment to 6 weeks after the start of the treatment protocol in the polynucleotide sodium-treated patients than in the patients who were treated with other agents (p = 0.006, one-way ANOVA). There were no significant between-group differences in the other secondary endpoints. No adverse events occurred. In conclusion, polynucleotide sodium could effectively reduce weight-bearing pain in the patients with knee osteoarthritis compared to standard hyaluronic acid viscosupplementation.
Analysis of the Clinical and Epidemiological Meaning of Screening Test for SARS-CoV-2: Considerations in the Chronic Kidney Disease Patients during the COVID-19 Pandemic
Authors: Martino Francesca , Amici Gianpaolo , Grandesso Stefano , Ferraro Mortellaro Rosella , Lo Cicero Antonina , Novara Giacomo
Published: March 2021

The COronaVIrus Disease 19 (COVID-19) pandemic is an emerging reality in nephrology. In a continuously changing scenario, we need to assess our patients’ additional risk in terms of attending hemodialysis treatments, follow-up peritoneal dialysis, and kidney transplant visits. The prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-20 infection in the general population plays a pivotal role in estimating the additional COVID-19 risk in chronic kidney disease (CKD) patients. Unfortunately, local prevalence is often obscure, and when we have an estimation, we neglect the number of asymptomatic subjects in the same area and, consequently, the risk of infection in CKD patients. Furthermore, we still have the problem of managing COVID-19 diagnosis and the test’s accuracy. Currently, the gold standard for SARS-CoV-2 detection is a real-time reverse transcription-polymerase chain reaction (rRT-PCR) on respiratory tract samples. rRT-PCR presents some vulnerability related to pre-analytic and analytic problems and could impact strongly on its diagnostic accuracy. Specifically, the operative proceedings to obtain the samples and the different types of diagnostic assay could affect the results of the test. In this scenario, knowing the local prevalence and the local screening test accuracy helps the clinician to perform preventive measures to limit the diffusion of COVID-19 in the CKD population.
Rural Districts and Business Agglomerations in Low-Density Business Environments. The Case of Extremadura (Spain)
Authors: Rangel-Preciado J. Francisco , Parejo-Moruno Francisco M. , Cruz-Hidalgo Esteban , Castellano-Álvarez Francisco J.
Published: March 2021

The strategy of the institutionalization and development of business agglomerations, in any of its analytical aspects (industrial district, local production system, cluster, etc.), has not had great results in Spanish regions with low business-density, probably due to the difficulty of finding an adequate implementation framework in administrative, geographic, and institutional terms. Based on the limitations presented by the identification methodologies of business agglomerations in low business-density territories, in this work we propose some methodological corrections that allow for reconciling these economic realities with the institutional and geographical framework offered by the local action groups (LAGs). This reconciliation is a useful tool to take advantage of the economies of agglomeration and, consequently, to explore the possibilities of endogenous development in rural areas, so that it can be a factor to take into account when planning and executing the public strategy of local and rural development. Finally, the results obtained for the specific case of Extremadura, the only Spanish region listed as a less developed one in European rural development policies, are presented.
Endocannabinoid System as Therapeutic Target of PTSD: A Systematic Review
Authors: Steardo Luca , Carbone Elvira Anna , Menculini Giulia , Moretti Patrizia , Steardo Luca , Tortorella Alfonso
Published: March 2021

Post-Traumatic Stress Disorder (PTSD) is a complex disorder involving dysregulation of stress-related hormones and neurotransmitter systems. Research focused on the endocannabinoid system (eCBS) for anxiety and stress regulation, cognitive and emotional responses modulation and aversive memories extinction, leading to the hypothesis that it could represent a possible alternative treatment target for PTSD. In this systematic review, we summarize evidence about the efficacy and safety of medicinal cannabidiol (CBD), Δ9-tetrahydrocannabinol (Δ9-THC), and nabilone in PTSD treatment. The PRISMA statement guidelines were followed. A systematic literature search was conducted in MEDLINE/PubMed, Scopus and Web of Science by two independent researchers, who also performed data extraction and quality assessment. Among the initial 495 papers, 234 were screened for eligibility and 10 were included. Studies suggested that different medicinal cannabinoids at distinct doses and formulations could represent promising treatment strategies for the improvement of overall PTSD symptomatology as well as specific symptom domains (e.g., sleep disorders, arousal disturbances, suicidal thoughts), also influencing quality of life, pain and social impact. Although there is a robust rationale for treatment with drugs that target the eCBS and the results are promising, further studies are needed to investigate the safety and efficacy profile of their prolonged use.
Synthesis of 1,5-Disubstituted Tetrazoles in Aqueous Micelles at Room Temperature
Authors: Abdessalam Mohammed , Sidhoum Madjid Ait , Zradni Fatima-Zohra , Ilikti Hocine
Published: March 2021

The ongoing study is a Ugi-azide four-component reaction for the synthesis of 1,5-disubstituted tetrazole(1,5-DST), which involves an aldehyde, different amines, isocyanides, and as azide’s source the Trimethylsilylazide (TMSN3), in water as solvent using as catalyst the tetradecyltrimethylammonium bromide (TTAB) with a load of (10% mole), which provides a hydrophobic micellar reaction site. This approach is a step toward a green chemistry reaction of 1,5 disubstituted tetrazole. A serie of 1, 5- disubstituted tetrazole was synthesized by engaging a large substrate scope, leading to yields between 43% and 56%, which are compared afterwards with those obtained with methanol as solvent. The results were confirmed by HRMS, IR, and 1D NMR experiments.
(E)-4-(3-(3-(4-Methoxyphenyl)acryloyl)phenoxy)butyl 2-Hydroxybenzoate
Authors: Ikhtiarudin Ihsan , Dona Rahma , Frimayanti Neni , Utami Rahayu , Susanti Emma , Mentari Mentari , Nurmaida Nurmaida , Agistia Nesa , Herfindo Noval , Zamri Adel
Published: March 2021

A new hybrid compound of chalcone-salicylate (title compound) has been successfully synthesized using a linker mode approach under reflux condition. The structure of the title compound has been established by spectroscopic analysis including UV-Vis, FT-IR, HRMS, 1D, and 2D NMR. Then, computational approach was also applied in this study through molecular docking and MD simulation to explore its potency against breast cancer. The results of the molecular docking study showed that the title compound exhibited more negative value of binding free energy (−8.15 kcal/mol) than tamoxifen (−7.00 kcal/mol). In addition, no striking change in the positioning of the interacting residues was recorded before and after the MD simulations. Based on the studies, it can be predicted that the title compound has a cytotoxic activity potency against breast cancer through ERα inhibition and it presumably can be developed as anticancer agent candidate.
Nitrogen Dissolution in Liquid Ga and Fe: Comprehensive Ab Initio Analysis, Relevance for Crystallization of GaN
Authors: Piechota Jacek , Krukowski Stanislaw , Sadovyi Petro , Sadovyi Bohdan , Porowski Sylwester , Grzegory Izabella
Published: March 2021

The dissolution of molecular nitrogen in Ga and Fe was investigated by ab initio calculations and some complementary experiments. It was found that the N bonding inside these solvents is fundamentally different. For Ga, it is between Ga4s and Ga4p and N2p states whereas for Fe this is by N2p to Fe4s, Fe4p and Fe3d states. Accordingly, the energy of dissolution of N2 for arbitrarily chosen starting atomic configurations was 0.535 eV/mol and −0.299 eV/mol for Ga and Fe, respectively. For configurations optimized with molecular dynamics, the difference between the corresponding energy values, 1.107 eV/mol and 0.003 eV/mol, was similarly large. Full thermodynamic analysis of chemical potential was made employing entropy-derived terms in a Debye picture. The entropy-dependent terms were obtained via a normal conditions path to avoid singularity of ideal gas entropy at zero K. Nitrogen solubility as a function of temperature and N2 pressure was evaluated, being much higher for Fe than for Ga. For T=1800 K and p=104 bar, the N concentration in Ga was 3×10−3 at. fr. whereas for Fe, it was 9×10−2 at. fr. in very good agreement with experimental data. It indicates that liquid Fe could be a prospective solvent for GaN crystallization from metallic solutions.
Adsorptive Removal of Phosphate from Aqueous Solutions Using Low-Cost Volcanic Rocks: Kinetics and Equilibrium Approaches
Authors: Mekonnen Dereje Tadesse , Alemayehu Esayas , Lennartz Bernd
Published: March 2021

The contamination of surface and groundwater with phosphate originating from industrial and household wastewater remains a serious environmental issue in low-income countries. Herein, phosphate removal from aqueous solutions was studied using low-cost volcanic rocks such as pumice (VPum) and scoria (VSco), obtained from the Ethiopian Great Rift Valley. Batch adsorption experiments were conducted using phosphate solutions with concentrations of 0.5 to 25 mg·L−1 to examine the adsorption kinetic as well as equilibrium conditions. The experimental adsorption data were tested by employing various equilibrium adsorption models, and the Freundlich and Dubinin-Radushkevich (D-R) isotherms best depicted the observations. The maximum phosphate adsorption capacities of VPum and VSco were calculated and found to be 294 mg·kg−1 and 169 mg·kg−1, respectively. A pseudo-second-order kinetic model best described the experimental data with a coefficient of correlation of R2 > 0.99 for both VPum and VSco; however, VPum showed a slightly better selectivity for phosphate removal than VSco. The presence of competitive anions markedly reduced the removal efficiency of phosphate from the aqueous solution. The adsorptive removal of phosphate was affected by competitive anions in the order: HCO3− >F− > SO4−2 > NO3− > Cl− for VPum and HCO3− > F− > Cl− > SO4−2 > NO3− for VSco. The results indicate that the readily available volcanic rocks have a good adsorptive capacity for phosphate and shall be considered in future studies as test materials for phosphate removal from water in technical-scale experiments.
Influence of Relative Displacement on Surface Roughness in Longitudinal Turning of X37CrMoV5-1 Steel
Authors: Skrzyniarz Michal , Nowakowski Lukasz , Miko Edward , Borkowski Krzysztof
Published: March 2021

The shaping process of surface texture is complicated and depends on many factors and phenomena accompanying them. This article presents the author’s test stand for the measurement of relative displacements in a tool–workpiece system during longitudinal turning. The aim of this study was to determine the influence of edge radius on the relative displacement between the tool and workpiece. The cutting process was carried out with inserts with different edge radii for X37CrMoV5-1 steel. As a result of the research, vibration charts of the tool–workpiece system were obtained. In the range of feed 0.03–0.18 mm/rev, the values of the standard deviation of relative displacements in the x-axis were obtained in the range of 0.36–0.78 μm for the insert with an edge radius of rn = 48.8 μm. As a result of the work, it was determined that for the feed value of 0.12 mm/rev for all inserts, the relative displacements are the smallest. As the final effect, the formula for forecasting the Ra roughness parameter was presented.
The Analysis of a Model–Task Dyad in Two Settings: Zaplify and Pencil and Paper
Authors: Güneş Canan
Published: March 2021

This paper examines the added value of a digital tool that constitutes a new model to introduce students to multiplication. Drawing on the theory of semiotic mediation, the semiotic potential of this new model is analysed with respect to the same task that can be solved in two different settings (the digital tool and pencil and paper). The analysis shows that the task solutions undergo significant changes depending on to the technological settings. Even though the end product of the model–task dyads might look the same in both settings, the product emerges from the different processes that would mediate quite different meanings for multiplication. This suggests that while designing tasks that involve mathematical models, rather than focusing only on the end product, considering the whole process would reveal the extensive potential meanings the model–task dyad can mediate.
The Early Fragmentation of a Bovine Dermis-Derived Collagen Barrier Membrane Contributes to Transmembraneous Vascularization—A Possible Paradigm Shift for Guided Bone Regeneration
Authors: Kapogianni Eleni , Alkildani Said , Radenkovic Milena , Xiong Xin , Krastev Rumen , Stöwe Ignacio , Bielenstein James , Jung Ole , Najman Stevo , Barbeck Mike , Rothamel Daniel
Published: March 2021

Collagen-based barrier membranes are an essential component in Guided Bone Regeneration (GBR) procedures. They act as cell-occlusive devices that should maintain a micromilieu where bone tissue can grow, which in turn provides a stable bed for prosthetic implantation. However, the standing time of collagen membranes has been a challenging area, as native membranes are often prematurely resorbed. Therefore, consolidation techniques, such as chemical cross-linking, have been used to enhance the structural integrity of the membranes, and by consequence, their standing time. However, these techniques have cytotoxic tendencies and can cause exaggerated inflammation and in turn, premature resorption, and material failures. However, tissues from different extraction sites and animals are variably cross-linked. For the present in vivo study, a new collagen membrane based on bovine dermis was extracted and compared to a commercially available porcine-sourced collagen membrane extracted from the pericardium. The membranes were implanted in Wistar rats for up to 60 days. The analyses included well-established histopathological and histomorphometrical methods, including histochemical and immunohistochemical staining procedures, to detect M1- and M2-macrophages as well as blood vessels. Initially, the results showed that both membranes remained intact up to day 30, while the bovine membrane was fragmented at day 60 with granulation tissue infiltrating the implantation beds. In contrast, the porcine membrane remained stable without signs of material-dependent inflammatory processes. Therefore, the bovine membrane showed a special integration pattern as the fragments were found to be overlapping, providing secondary porosity in combination with a transmembraneous vascularization. Altogether, the bovine membrane showed comparable results to the porcine control group in terms of biocompatibility and standing time. Moreover, blood vessels were found within the bovine membranes, which can potentially serve as an additional functionality of barrier membranes that conventional barrier membranes do not provide.
Analysis of Additional Load and Fatigue Life of Preloaded Bolts in a Flange Joint Considering a Bolt Bending Load
Authors: Okorn Ivan , Nagode Marko , Klemenc Jernej , Oman Simon
Published: March 2021

The influence of the working load on the dynamic loading of the bolt was investigated in our study for two cases of flange joints. The analytical calculation according to the Verein Deutscher Ingenieure (VDI) 2230 recommendation and the numerical analysis using the finite element method (FEM) were performed for a model of a four-bolt joint. To verify the FEM analysis, the forces in the bolts were measured during preloading and during the application of the working load on the test rig. Based on the analytical and numerical results, the influence of the working load application point on the bolt load and its fatigue life was analysed for different cases. Comparison of the results shows that the analytical method overestimates the additional bolt stresses at low working load, mainly due to the extremely large fraction of bending stress. As the working load increases, the differences between the two methods decrease, but only for the reason that the analytical method can only linearly scale the overestimated results at lower working load, and FEM analysis, on the other hand, shows a progressive increase of the additional stress in the bolt at higher working loads due to the spreading of the flange. It is also shown that a high washer significantly increases the fatigue life of the bolt for two reasons: (i) a high washer reduces the additional stress in the bolt, and (ii) the high washer shifts the critical fatigue point from the thread area to the transition of the bolt shank to the head.
Cleavage Stress Producing Notch-Induced Anisotropic Fracture and Crack Path Deflection in Cold Drawn Pearlitic Steel
Authors: Toribio Jesús , Ayaso Francisco-Javier
Published: March 2021

The fracture performance of axisymmetric notched samples taken from pearlitic steels with different levels of cold-drawing is studied. To this end, a real manufacture chain was stopped in the course of the process (on-site in the factory), and samples of all intermediate stages were extracted from the initial hot-rolled bar (not cold-drawn at all) to the final commercial product (prestressing steel wire). Thus, the drawing intensity or straining level (represented by the yield strength) is treated as the key variable to elucidate the consequences of manufacturing on the posterior fracture issues. On the basis of a materials science approach, the clearly anisotropic fracture behavior of heavily drawn steels (exhibiting deflection in the fracture surface) is rationalized on the basis of the markedly oriented pearlitic microstructure of the cold-drawn steel that influences the operative micromechanism of fracture. In addition, a finite element analysis of the stress distribution at the fracture instant allows the computation of the cleavage annular stress required to produce anisotropic fracture behavior and thus crack path deflection associated with mixed-mode cracking. Results show that such a stress is the variable governing initiation and propagation of anisotropic fracture by cleavage (a specially oriented and enlarged cleavage fracture) appearing along the wire axis direction in the case of sharply-notched samples of heavily drawn pearlitic steels.
Quantitative Correlation and Control Strategy for Element Content Fluctuation along Casting Direction in Central Area of Continuous Casting Billet
Authors: Guo Dongwei , Hou Zibing , Peng Zhiqiang , Liu Qian , Cao Jianghai
Published: March 2021

The statistical correlation was applied to analyze the specific and quantitative correlation relationship between the solidification structure and central segregation along the casting direction in carbon steel billet. On this basis, the segregation formation mechanism of the solute element and related control strategy were investigated. It is found that the equiaxed crystal zone fluctuation along the casting direction determines the fluctuation degree of central segregation. At the same time, the central segregation at a certain position is mostly affected by the equiaxed crystal zone width at the hysteretic position. Moreover, the casting speed can influence the columnar to equiaxed transition (CET) fluctuation along the casting direction by affecting the flow of molten steel in the billet. Overall, the segregation mechanism of solute elements along the casting direction can be summarized into two aspects: First, with the growth of columnar crystals in the initial stage, the segregated solutes are continuously enriched and distributed in the equiaxed crystal zone after CET. The fluctuation of the equiaxed crystal zone will affect the distribution of the enriched solute in the billet and cause the fluctuation of the central segregation. Second, due to the solidification shrinkage at the end of solidification, the solute-enriched liquid phase at the hysteretic position is pumped to the solidification endpoint and forms the central V-shaped segregation. Meanwhile, the stable solidification structure (columnar crystal length or equiaxed crystal zone width) along the casting direction and control measures preceded equiaxed crystal zone formation are beneficial to reduce the central V-shaped segregation.
Pre-Diagnostic Circulating Metabolites and Colorectal Cancer Risk in the Cancer Prevention Study-II Nutrition Cohort
Authors: McCullough Marjorie L. , Hodge Rebecca A. , Campbell Peter T. , Stevens Victoria L. , Wang Ying
Published: March 2021

Untargeted metabolomic studies have identified potential biomarkers of colorectal cancer risk, but evidence is still limited and broadly inconsistent. Among 39,239 Cancer Prevention Study II Nutrition cohort participants who provided a blood sample between 1998–2001, 517 newly diagnosed colorectal cancers were identified through 30 June 2015. In this nested case–control study, controls were matched 1:1 to cases on age, sex, race and date of blood draw. Mass spectroscopy-based metabolomic analyses of pre-diagnostic plasma identified 886 named metabolites, after quality control exclusions. Conditional logistic regression models estimated multivariable-adjusted odds ratios (OR) and 95% confidence intervals (CI) for 1 standard deviation (SD) increase in each metabolite with risk of colorectal cancer. Six metabolites were associated with colorectal cancer risk at a false discovery rate < 0.20. These metabolites were of several classes, including cofactors and vitamins, nucleotides, xenobiotics, lipids and amino acids. Five metabolites (guanidinoacetate, 2’-O-methylcytidine, vanillylmandelate, bilirubin (E,E) and N-palmitoylglycine) were positively associated (OR per 1 SD = 1.29 to 1.32), and one (3-methylxanthine) was inversely associated with CRC risk (OR = 0.79, 95% CI, 0.69–0.89). We did not replicate findings from two earlier prospective studies of 250 cases each after adjusting for multiple comparisons. Large pooled prospective analyses are warranted to confirm or refute these findings and to discover and replicate metabolites associated with colorectal cancer risk.
High-Throughput Cell Trapping in the Dentate Spiral Microfluidic Channel
Authors: Lu Jiawei , Dai Bo , Wang Kan , Long Yan , Yang Zhuoqing , Chen Junyi , Huang Shaoqi , Zheng Lulu , Fu Yongfeng , Wan Wenbin , Zhuang Songlin , Guan Yangtai , Zhang Dawei
Published: March 2021

Cell trapping is a very useful technique in a variety of cell-based assays and cellular research fields. It requires a high-throughput, high-efficiency operation to isolate cells of interest and immobilize the captured cells at specific positions. In this study, a dentate spiral microfluidic structure is proposed for cell trapping. The structure consists of a main spiral channel connecting an inlet and an out and a large number of dentate traps on the side of the channel. The density of the traps is high. When a cell comes across an empty trap, the cell suddenly makes a turn and enters the trap. Once the trap captures enough cells, the trap becomes closed and the following cells pass by the trap. The microfluidic structure is optimized based on the investigation of the influence over the flow. In the demonstration, 4T1 mouse breast cancer cells injected into the chip can be efficiently captured and isolated in the different traps. The cell trapping operates at a very high flow rate (40 μL/s) and a high trapping efficiency (>90%) can be achieved. The proposed high-throughput cell-trapping technique can be adopted in the many applications, including rapid microfluidic cell-based assays and isolation of rare circulating tumor cells from a large volume of blood sample.