bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of the Renin–Angiotensin–Aldosterone System in Dystrophin-Deficient Cardiomyopathy
Authors: Rodriguez-Gonzalez Moises , Lubian-Gutierrez Manuel , Cascales-Poyatos Helena Maria , Perez-Reviriego Alvaro Antonio , Castellano-Martinez Ana
Published: December 2020

Dystrophin-deficient cardiomyopathy (DDC) is currently the leading cause of death in patients with dystrophinopathies. Targeting myocardial fibrosis (MF) has become a major therapeutic goal in order to prevent the occurrence of DDC. We aimed to review and summarize the current evidence about the role of the renin–angiotensin–aldosterone system (RAAS) in the development and perpetuation of MF in DCC. We conducted a comprehensive search of peer-reviewed English literature on PubMed about this subject. We found increasing preclinical evidence from studies in animal models during the last 20 years pointing out a central role of RAAS in the development of MF in DDC. Local tissue RAAS acts directly mainly through its main fibrotic component angiotensin II (ANG2) and its transducer receptor (AT1R) and downstream TGF-b pathway. Additionally, it modulates the actions of most of the remaining pro-fibrotic factors involved in DDC. Despite limited clinical evidence, RAAS blockade constitutes the most studied, available and promising therapeutic strategy against MF and DDC. Conclusion: Based on the evidence reviewed, it would be recommendable to start RAAS blockade therapy through angiotensin converter enzyme inhibitors (ACEI) or AT1R blockers (ARBs) alone or in combination with mineralocorticoid receptor antagonists (MRa) at the youngest age after the diagnosis of dystrophinopathies, in order to delay the occurrence or slow the progression of MF, even before the detection of any cardiovascular alteration.
Vanillic Acid, a Bioactive Phenolic Compound, Counteracts LPS-Induced Neurotoxicity by Regulating c-Jun N-Terminal Kinase in Mouse Brain
Authors: Ullah Rahat , Ikram Muhammad , Park Tae Ju , Ahmad Riaz , Saeed Kamran , Alam Sayed Ibrar , Rehman Inayat Ur , Khan Amjad , Khan Ibrahim , Jo Min Gi , Kim Myeong Ok
Published: December 2020

The receptor for advanced glycation end products (RAGE), a pattern recognition receptor signaling event, has been associated with several human illnesses, including neurodegenerative diseases, particularly in Alzheimer’s disease (AD). Vanillic acid (V.A), a flavoring agent, is a benzoic acid derivative having a broad range of biological activities, including antioxidant, anti-inflammatory, and neuroprotective effects. However, the underlying molecular mechanisms of V.A in exerting neuroprotection are not well investigated. The present study aims to explore the neuroprotective effects of V.A against lipopolysaccharides (LPS)-induced neuroinflammation, amyloidogenesis, synaptic/memory dysfunction, and neurodegeneration in mice brain. Behavioral tests and biochemical and immunofluorescence assays were applied. Our results indicated increased expression of RAGE and its downstream phospho-c-Jun n-terminal kinase (p-JNK) in the LPS-alone treated group, which was significantly reduced in the V.A + LPS co-treated group. We also found that systemic administration of LPS-injection induced glial cells (microglia and astrocytes) activation and significantly increased expression level of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB) and secretion of proinflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-1 β (IL1-β), and cyclooxygenase (COX-2). However, V.A + LPS co-treatment significantly inhibited the LPS-induced activation of glial cells and neuroinflammatory mediators. Moreover, we also noted that V.A treatment significantly attenuated LPS-induced increases in the expression of AD markers, such as β-site amyloid precursor protein (APP)–cleaving enzyme 1 (BACE1) and amyloid-β (Aβ). Furthermore, V.A treatment significantly reversed LPS-induced synaptic loss via enhancing the expression level of pre- and post-synaptic markers (PSD-95 and SYP), and improved memory performance in LPS-alone treated group. Taken together; we suggest that neuroprotective effects of V.A against LPS-induced neurotoxicity might be via inhibition of LPS/RAGE mediated JNK signaling pathway; and encourage future studies that V.A would be a potential neuroprotective and neurotherapeutic candidate in various neurological disorders.
Vitamin D Modulates Intestinal Microbiota in Inflammatory Bowel Diseases
Authors: Battistini Carolina , Ballan Rafael , Herkenhoff Marcos Edgar , Saad Susana Marta Isay , Sun Jun
Published: December 2020

Inflammatory bowel disease (IBD) is a chronic inflammation of the gastrointestinal tract (GIT), including Crohn’s disease (CD) and ulcerative colitis (UC), which differ in the location and lesion extensions. Both diseases are associated with microbiota dysbiosis, with a reduced population of butyrate-producing species, abnormal inflammatory response, and micronutrient deficiency (e.g., vitamin D hypovitaminosis). Vitamin D (VitD) is involved in immune cell differentiation, gut microbiota modulation, gene transcription, and barrier integrity. Vitamin D receptor (VDR) regulates the biological actions of the active VitD (1α,25-dihydroxyvitamin D3), and is involved in the genetic, environmental, immune, and microbial aspects of IBD. VitD deficiency is correlated with disease activity and its administration targeting a concentration of 30 ng/mL may have the potential to reduce disease activity. Moreover, VDR regulates functions of T cells and Paneth cells and modulates release of antimicrobial peptides in gut microbiota-host interactions. Meanwhile, beneficial microbial metabolites, e.g., butyrate, upregulate the VDR signaling. In this review, we summarize the clinical progress and mechanism studies on VitD/VDR related to gut microbiota modulation in IBD. We also discuss epigenetics in IBD and the probiotic regulation of VDR. Furthermore, we discuss the existing challenges and future directions. There is a lack of well-designed clinical trials exploring the appropriate dose and the influence of gender, age, ethnicity, genetics, microbiome, and metabolic disorders in IBD subtypes. To move forward, we need well-designed therapeutic studies to examine whether enhanced vitamin D will restore functions of VDR and microbiome in inhibiting chronic inflammation.
Polycyclic Aromatic Hydrocarbons Activate the Aryl Hydrocarbon Receptor and the Constitutive Androstane Receptor to Regulate Xenobiotic Metabolism in Human Liver Cells
Authors: Goedtke Lisa , Sprenger Heike , Hofmann Ute , Schmidt Felix F. , Hammer Helen S. , Zanger Ulrich M. , Poetz Oliver , Seidel Albrecht , Braeuning Albert , Hessel-Pras Stefanie
Published: December 2020

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants produced by incomplete combustion of organic matter. They induce their own metabolism by upregulating xenobiotic-metabolizing enzymes such as cytochrome P450 monooxygenase 1A1 (CYP1A1) by activating the aryl hydrocarbon receptor (AHR). However, previous studies showed that individual PAHs may also interact with the constitutive androstane receptor (CAR). Here, we studied ten PAHs, different in carcinogenicity classification, for their potential to activate AHR- and CAR-dependent luciferase reporter genes in human liver cells. The majority of investigated PAHs activated AHR, while non-carcinogenic PAHs tended to activate CAR. We further characterized gene expression, protein abundancies and activities of the AHR targets CYP1A1 and 1A2, and the CAR target CYP2B6 in human HepaRG hepatoma cells. Enzyme induction patterns strongly resembled the profiles obtained at the receptor level, with AHR-activating PAHs inducing CYP1A1/1A2 and CAR-activating PAHs inducing CYP2B6. In summary, this study provides evidence that beside well-known activation of AHR, some PAHs also activate CAR, followed by subsequent expression of respective target genes. Furthermore, we found that an increased PAH ring number is associated with AHR activation as well as the induction of DNA double-strand breaks, whereas smaller PAHs activated CAR but showed no DNA-damaging potential.
Intervertebral Disc and Adipokine Leptin—Loves Me, Loves Me Not
Authors: Curic Goran
Published: December 2020

Leptin—the most famous adipose tissue-secreted hormone—in the human body is mostly observed in a negative connotation, as the hormone level increases with the accumulation of body fat. Nowadays, fatness is becoming another normal body shape. Fatness is burdened with numerous illnesses—including low back pain and degenerative disease of lumbar intervertebral disc (IVD). IVD degeneration and IVD inflammation are two indiscerptible phenomena. Irrespective of the underlying pathophysiological background (trauma, obesity, nutrient deficiency), the inflammation is crucial in triggering IVD degeneration. Leptin is usually depicted as a proinflammatory adipokine. Many studies aimed at explaining the role of leptin in IVD degeneration, though mostly in in vitro and on animal models, confirmed leptin’s “bad reputation”. However, several studies found that leptin might have protective role in IVD metabolism. This review examines the current literature on the metabolic role of different depots of adipose tissue, with focus on leptin, in pathogenesis of IVD degeneration.
LAG-3, TIM-3 and VISTA Expression on Tumor-Infiltrating Lymphocytes in Oropharyngeal Squamous Cell Carcinoma—Potential Biomarkers for Targeted Therapy Concepts
Authors: Wuerdemann Nora , Pütz Katharina , Eckel Hans , Jain Rishabh , Wittekindt Claus , Huebbers Christian U. , Sharma Shachi J. , Langer Christine , Gattenlöhner Stefan , Büttner Reinhard , Speel Ernst-Jan , Suchan Malte , Wagner Steffen , Quaas Alexander , Klussmann Jens P.
Published: December 2020

Tumor growth and survival requires a particularly effective immunosuppressant tumor microenvironment (TME) to escape destruction by the immune system. While immunosuppressive checkpoint markers like programmed cell death 1 ligand (PD-L1) are already being targeted in clinical practice, lymphocyte-activation-protein 3 (LAG-3), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and V-domain Ig suppressor of T cell activation (VISTA) inhibitors are currently under investigation in clinical trials. Reliable findings on the expression status of those immune checkpoint inhibitors on tumor-infiltrating lymphocytes (TILs) in the TME of oropharyngeal squamous cell carcinoma (OPSCC) are lacking. This work aims to describe the expression of LAG-3, TIM-3, and VISTA expression in the TME of OPSCC. We created a tissue microarray of paraffin-embedded tumor tissue of 241 OPSCC. Expression of the immune checkpoint protein LAG-3, TIM-3, and VISTA in OPSCC was evaluated using immunohistochemistry and results were correlated with CD8+ T-cell inflammation and human papillomavirus (HPV)-status. 73 OPSCC stained positive for LAG-3 (31%; HPV+:44%; HPV-:26%, p = 0.006), 122 OPSCC stained positive for TIM-3 (51%; HPV+:70%; HPV-:44%, p < 0.001) and 168 OPSCC (70%; HPV+:75%; HPV-:68%, p = 0.313) for VISTA. CD8+ T-cells were significantly associated with LAG-3, TIM-3 and VISTA expression (p < 0.001, p < 0.001, p = 0.007). Immune checkpoint therapy targeting LAG-3, TIM-3, and/or VISTA could be a promising treatment strategy especially in HPV-related OPSCC. Future clinical trials investigating the efficacy of a checkpoint blockade in consideration of LAG-3, TIM-3, and VISTA expression are required.
Expanding the Clinical and Genetic Spectrum of RAB28-Related Cone-Rod Dystrophy: Pathogenicity of Novel Variants in Italian Families
Authors: Iarossi Giancarlo , Marino Valerio , Maltese Paolo Enrico , Colombo Leonardo , D’Esposito Fabiana , Manara Elena , Dhuli Kristjana , Modarelli Antonio Mattia , Cennamo Gilda , Magli Adriano , Dell’Orco Daniele , Bertelli Matteo
Published: December 2020

The small Ras-related GTPase Rab-28 is highly expressed in photoreceptor cells, where it possibly participates in membrane trafficking. To date, six alterations in the RAB28 gene have been associated with autosomal recessive cone-rod dystrophies. Confirmed variants include splicing variants, missense and nonsense mutations. Here, we present a thorough phenotypical and genotypical characterization of five individuals belonging to four Italian families, constituting the largest cohort of RAB28 patients reported in literature to date. All probands displayed similar clinical phenotype consisting of photophobia, decreased visual acuity, central outer retinal thinning, and impaired color vision. By sequencing the four probands, we identified: a novel homozygous splicing variant; two novel nonsense variants in homozygosis; a novel missense variant in compound heterozygous state with a previously reported nonsense variant. Exhaustive molecular dynamics simulations of the missense variant p.(Thr26Asn) in both its active and inactive states revealed an allosteric structural mechanism that impairs the binding of Mg2+, thus decreasing the affinity for GTP. The impaired GTP-GDP exchange ultimately locks Rab-28 in a GDP-bound inactive state. The loss-of-function mutation p.(Thr26Asn) was present in a compound heterozygosis with the nonsense variant p.(Arg137*), which does not cause mRNA-mediated decay, but is rather likely degraded due to its incomplete folding. The frameshift p.(Thr26Valfs4*) and nonsense p.(Leu13*) and p.(Trp107*) variants, if translated, would lack several key structural components necessary for the correct functioning of the encoded protein.
Exosomal miRNAs as Potential Biomarkers to Monitor Phosphodiesterase 5 Inhibitor Induced Anti-Fibrotic Effects on CCl4 Treated Rats
Authors: Broermann Andre , Schmid Ramona , Gabrielyan Ogsen , Sakowski Marlene , Eisele Claudia , Keller Sascha , Wolff Michael , Baum Patrick , Stierstorfer Birgit , Huber Jochen , Krämer Bernhard K. , Hocher Berthold , Streicher Ruediger , Delić Denis
Published: December 2020

MicroRNAs (miRNAs) are short, non-coding RNA species that are important post-transcriptional regulators of gene expression and play an important role in the pathogenesis of non-alcoholic fatty liver disease. Here, we investigated the phosphodiesterase 5 (PDE5) inhibitor induced effects on hepatic and plasma exosomal miRNA expression in CCl4-treated rats. In the present study, hepatic miRNA profiling was conducted using the Nanostring nCounter technology and mRNA profiling using RNA sequencing from PDE5 treated rats in the model of CCl4-induced liver fibrosis. To evaluate if the PDE5 inhibitor affected differentially expressed miRNAs in the liver can be detected in plasma exosomes, qRT-PCR specific assays were used. In livers from CCl4-treated rats, the expression of 22 miRNAs was significantly increased (>1.5-fold, adj. p < 0.05), whereas the expression of 16 miRNAs was significantly decreased (>1.5-fold, adj. p < 0.05). The majority of the deregulated miRNA species are implicated in fibrotic and inflammatory processes. The PDE5 inhibitor suppressed the induction of pro-fibrotic miRNAs, such as miR-99b miR-100 and miR-199a-5p, and restored levels of anti-fibrotic miR-122 and miR-192 in the liver. In plasma exosomes, we observed elevated levels of miR-99b, miR-100 and miR-142-3p after treatment with the PDE5-inhibitor compared to CCl4/Vehicle-treated. Our study demonstrated for the first time that during the development of hepatic fibrosis in the preclinical model of CCl4-induced liver fibrosis, defined aspects of miRNA regulated liver pathogenesis are influenced by PDE5 treatment. In conclusion, miRNA profiling of plasma exosomes might be used as a biomarker for NASH progression and monitoring of treatment effects.
Experimental and Numerical Studies on Thermally-Induced Slip Ratcheting on a Slope
Authors: Kim Sihyun , Kim Seunghee , Zhang Jingtao , Druszkowski Ethan , Sweidan Abdallah
Published: December 2020

Mild temperature fluctuation of a material sitting on a slope may only cause a small slip, but a large number of the repeated temperature changes can amplify the magnitude of the overall slip and eventually bring an issue of structural instability. The slip accumulation starts from the minor magnitude and reaches the extensive level called “slip ratcheting”. Experimental evidence for such thermally-induced slip ratcheting is first provided in this work. It is implemented with an acryl sheet placed on an inclined wood with a mild angle; it is found that the temperature fluctuation of the acryl sheet causes the sheet to slide down gradually without any additional loading. The numerical model is then attempted to emulate the major findings of the experiments. From the simulation work, the location of a neutral point is found when the acryl plate is heated, and another neutral point is observed when cooled down. The shift of the neutral point appears to be a major reason for the unrecovered slip after a temperature increase and decrease cycle. Finally, a parametric study using the numerical model is carried out to examine which parameters play a major role in the development of residual slips.
Darwin Returns to the Galapagos: Genetic and Morphological Analyses Confirm the Presence of Tramea darwini at the Archipelago (Odonata, Libellulidae)
Authors: Lorenzo-Carballa María , Garrison Rosser , Encalada Andrea , Cordero-Rivera Adolfo
Published: December 2020

The status of the Tramea species present in the Galapagos Islands (Odonata, Libellulidae) has been the subject of a long-standing debate among odonatologists. Here, we use molecular and morphological data to analyze a series of specimens from this genus collected in 2018 from the Islands of San Cristobal, Isabela, and Santa Cruz, with the aim of determining their relationship with Tramea calverti Muttkowski and with their currently considered senior synonym T. cophysa Hagen. We combined sequencing of mitochondrial and nuclear DNA with morphological examination of several specimens of Tramea, including representatives of continental T. cophysa and T. calverti. Our molecular analyses place the Tramea from Galapagos in the same clade as T. calverti, with T. cophysa as a closely related species. The morphological analyses found only one consistent difference between T. cophysa and T. calverti: the presence of an accessory lobe in the male vesica spermalis of T. cophysa that is absent in T. calverti and in the Tramea from Galapagos. In agreement with our genetic results, the overall morphological differences documented by us indicate that the Galapagos material examined is conspecific with T. calverti. In light of this, and following the principle of priority in taxonomic nomenclature, Tramea calverti Muttkowski, 1910 should hereafter be considered a junior synonym of Tramea darwini Kirby, 1889.
Wavelength Shifters for Applications in Liquid Argon Detectors
Authors: Kuźniak Marcin , Szelc Andrzej M.
Published: December 2020

Wavelength shifters and their applications for liquid argon detectors have been a subject of extensive R&D procedures over the past decade. This work reviews the most recent results in this field. We compare the optical properties and usage details together with the associated challenges for various wavelength shifting solutions. We discuss the current status and potential future R&D directions for the main classes of wavelength shifters.
Short-and-Long-Term Outcomes after Coronary Rotational Atherectomy in Patients Treated with Trans-Catheter Aortic Valve Implantation
Authors: Lunardi Mattia , Pighi Michele , Venturi Gabriele , Del Sole Paolo Alberto , Pesarini Gabriele , Mainardi Andrea , Scarsini Roberto , Ferrero Valeria , Gottin Leonardo , Ribichini Flavio
Published: December 2020

Background. Coronary artery disease (CAD) is a common finding among patients undergoing trans-catheter aortic valve implantation (TAVI), who often present severely calcified coronary lesions. Evidence is scarce about the use of rotational atherectomy (RA) in this setting, in particular regarding long-term outcome. Methods. RA was performed on severely calcified coronary lesions concomitant with TAVI in a consecutive series of patients treated between 2010 and 2020. Immediate and long-term clinical outcomes are reported. Results. A concomitant CAD (coronary stenosis visually > 50%) was observed in 402/845 (47.6%) consecutive patients undergoing TAVI at the University Hospital of Verona. Angioplasty was performed in 104 patients (12.3%). Among these, 19 patients (18.3%, 20 coronary arteries), were treated with RA after TAVI: 10 after implantation of a balloon-expandable trans-catheter valve and 9 after a self-expandable valve. All procedures were successful. Hypotension occurred in 3 patients (15.8%), with rapid recovery after the procedure; CI-AKI (contrast-induced acute kidney injury) in 3 patients (15.8%), of which two recovered within discharge. At a median follow-up of 21.5 months (Q1–3: 6–36) event free survival was 83.3%. Only one patient suffered a target vessel failure >2 years after RA. Neither stroke nor peri-procedural infarctions were detected. Conclusions. RA concomitant with TAVI was feasible and safe in patients treated with implantation of either self-expandable, or balloon-expandable trans-catheter aortic valves. Long-term clinical events related to the coronary procedure were extremely infrequent and the survival rate at median follow-up of 21.5 months was 83.3%.
Therapeutics Development for Pseudoxanthoma Elasticum and Related Ectopic Mineralization Disorders: Update 2020
Authors: Luo Hongbin , Li Qiaoli , Cao Yi , Uitto Jouni
Published: December 2020

Pseudoxanthoma elasticum (PXE), the prototype of heritable ectopic mineralization disorders, manifests with deposition of calcium hydroxyapatite crystals in the skin, eyes and arterial blood vessels. This autosomal recessive disorder, due to mutations in ABCC6, is usually diagnosed around the second decade of life. In the spectrum of heritable ectopic mineralization disorders are also generalized arterial calcification of infancy (GACI), with extremely severe arterial calcification diagnosed by prenatal ultrasound or perinatally, and arterial calcification due to CD73 deficiency (ACDC) manifesting with arterial and juxta-articular mineralization in the elderly; the latter disorders are caused by mutations in ENPP1 and NT5E, respectively. The unifying pathomechanistic feature in these three conditions is reduced plasma levels of inorganic pyrophosphate (PPi), a powerful endogenous inhibitor of ectopic mineralization. Several on-going attempts to develop treatments for these conditions, either with the goal to normalize PPi plasma levels or by means of preventing calcium hydroxyapatite deposition independent of PPi, are in advanced preclinical levels or in early clinical trials. This overview summarizes the prospects of treatment development for ectopic mineralization disorders, with PXE, GACI and ACDC as the target diseases, from the 2020 vantage point.
Real-World Administration of Once-Daily MeltDose® Prolonged-Release Tacrolimus (LCPT) Allows for Dose Reduction of Tacrolimus and Stabilizes Graft Function Following Liver Transplantation
Authors: Willuweit Katharina , Frey Alexandra , Hörster Anne , Saner Fuat , Herzer Kerstin
Published: December 2020

The calcineurin inhibitor tacrolimus is included in most immunosuppressive protocols after liver transplantation. This retrospective, observational 24-month study investigated the tolerability of once-daily MeltDose® prolonged-release tacrolimus (LCPT) after switching from twice-daily immediate-release tacrolimus (IR-Tac) in a real-world cohort of 150 patients with previous liver transplantation. No graft rejection or new safety signals were observed. Only 7.3% of patients discontinued LCPT due to side effects. In the overall patient population, median liver transaminases, total cholesterol, triglycerides, glucose, and HbA1c remained constant after switching to LCPT. Total cholesterol significantly decreased (p ≤ 0.002) in patients with initially elevated levels (>200 mg/dL). A total of 71.8% of 96 patients maintained a glomerular filtration rate > 60 mL/min/1.73 m2 throughout the study, while 44.7% of patients were classified as fast metabolizers and 55.3% as slow metabolizers. Median daily tacrolimus dose could be reduced by 50% in fast metabolizers and by 30% in slow metabolizers, while trough levels were maintained in the target range (4–6 ng/mL). In conclusion, our observational study confirmed previous evidence of good overall tolerability and a favorable outcome for the patients after switching from IR-Tac to LCPT after liver transplantation.
The Utility of Anti-Covid-19 Desks in Italy, Doubts and Criticism
Authors: Bergamin Marco , Musumeci Giuseppe
Published: December 2020

As of the 14th of September, Italy has been considered one of the more susceptible nations in terms of risk of increase for Sars-Cov-2 contagion [...]
Effects of Preferred and Non-Preferred Warm-Up Music on Resistance Exercise Performance
Authors: Ballmann Christopher G. , Cook Georgia D. , Hester Zachary T. , Kopec Thomas J. , Williams Tyler D. , Rogers Rebecca R.
Published: December 2020

The purpose of this study was to examine the effects of listening to preferred and non-preferred warm-up music on upper-body resistance exercise performance. Resistance-trained males (ages 18–24) participated in two separate bench press trials each with a different warm-up music condition: preferred warm-up music (PREF) or non-preferred warm-up music (NON-PREF). In each trial, participants listened to PREF or NON-PREF music during a standardized bench press warm-up. Following the warm-up, motivation to exercise was measured using a visual analog scale followed by two sets × repetitions to failure (RTF) at 75% of 1-RM separated by 1 min of rest. A linear position transducer was used to measure mean barbell velocity. Rate of perceived exertion (RPE) was obtained after each set. RTF, velocity, RPE, and motivation were analyzed. RTF were significantly higher during the PREF versus NON-PREF trail (p = 0.001) while mean barbell velocity remained unchanged (p = 0.777). RPE was not significantly different between PREF and NON-PREF trials (p = 0.735). Motivation to exercise was significantly higher during the PREF versus NON-PREF trial (p < 0.001). Findings show that listening to PREF music during a warm-up improves subsequent RTF performance during bench press exercise. However, barbell velocity was largely unaffected. While perceived exertion was similar between trials, motivation to exercise was markedly increased during the PREF warm-up music trial. These findings suggest that competitors listening to warm-up music before giving maximal effort during resistance exercise could optimize performance by ensuring self-selection of their own preferred music.
Bio-Based Adhesives for Wooden Boatbuilding
Authors: Corigliano Pasqualino , Crupi Vincenzo , Bertagna Serena , Marinò Alberto
Published: December 2020

The aim of the present investigation was to assess the behaviour of strip-planked parts by comparing wooden specimens glued using two different bio-based adhesives with wooden specimens glued using a conventional epoxy resin generally used in boatbuilding. Experimental tests in accordance with UNI EN standards were performed in order to evaluate mechanical properties such as tensile strength, shear strength, elastic modulus and shear modulus. In addition, compression shear tests were performed in order to assess the shear modulus of the adhesives. The obtained results demonstrate that the mechanical properties of the investigated bio-based adhesives are comparable to, and sometimes better than, the conventional epoxy resin. Moreover, the experimental results give useful information for the design of wooden boats when the strip-planking process is used. Furthermore, a new procedure to assess the shear modulus of elasticity and shear strength, using the application of compression loadings, was proposed. The results were compared to standard lap-joint tests and showed even lower dispersion. Consequently, the testing procedure proposed by the authors is valid to assess shear properties under compression loading, and it can be applied in most laboratories since it involves the use of common testing devices.
Offshore Wind Energy Resource in the Kingdom of Morocco: Assessment of the Seasonal Potential Variability Based on Satellite Data
Authors: Benazzouz Aïssa , Mabchour Hassan , El Had Khalid , Zourarah Bendahhou , Mordane Soumia
Published: December 2020

This study provides a first estimate of the offshore wind power potential along the Moroccan Atlantic shelf based on remotely sensed data. An in-depth knowledge of wind potential characteristics allows assessment of the offshore wind energy project. Based on consistent daily satellite data retrieved from the Advanced Scatterometer (ASCAT) spanning the period from 2008 to 2017, the seasonal wind characteristics were statistically analyzed using the climatological Weibull distribution functions and an assessment of the Moroccan potential coastal wind energy resources was qualitatively analyzed across a range of sites likely to be suitable for possible exploitation. Also, an atlas of wind power density (WPD) at a height of 80 m was provided for the whole Moroccan coast. An examination of the bathymetrical conditions of the study area was carried out since bathymetry is among the primary factors that need to be examined with the wind potential during offshore wind project planning. The results were presented based on the average wind intensity and the prevailing direction, and also the wind power density was shown at monthly, seasonal and interannual time scale. The analysis indicated that the coastal wind regime of the southern area of Morocco has the greatest energy potential, with an average power density which can reach in some places a value around 450 W/m2 at heights of 10 m and 80 m above sea level (a.s.l) (wind turbine hub height) more particularly in the south of the country.
Design Errors in Ship Design
Authors: Andrews David
Published: December 2020

There is a problem in coping with design errors in ship design. Ships are generally very large and often very complex. Yet, we rarely invest in full-scale prototypes so design errors are frequently revealed once ships are at sea and certain errors can be catastrophic, others lead to many ships having shortened useful lives. The paper starts by considering the nature of design errors and failures in large-scale engineering enterprises. This is followed by looking briefly at some lessons from maritime history concerning how design errors arise and can even lead to ships sinking. A specific well-documented case of calculation error in sizing a new ship design is reviewed and lessons drawn. The relevance of general approaches to avoiding engineering errors and ever-greater emphasis on risk mitigation procedures and applying safety regimes alongside ethical guidance is reviewed. The changing nature of ship design practice is discussed, with ship designers between the horns of the dilemma of ever greater ability provided by computer driven precision and the demands for their designs to be seen to perform effectively in an increasingly uncertain and complex world. Final thoughts consider the basis for judging what might be good or bad ship designs, how errors can be addressed, and the ultimate safety role of the naval architect as the overall designer of complex vessels.
SARS-CoV-2 Spike Protein and Lung Vascular Cells
Authors: Suresh Sri Jayalakshmi , Suzuki Yuichiro Justin
Published: December 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing the current pandemic of coronavirus disease 2019 (COVID-19), and COVID-19 vaccines focus on its spike protein. However, in addition to facilitating the membrane fusion and viral entry, the SARS-CoV-2 spike protein promotes cell growth signaling in human lung vascular cells, and patients who have died of COVID-19 have thickened pulmonary vascular walls, linking the spike protein to a fatal disease, pulmonary arterial hypertension (PAH). In addition to SARS-CoV spike proteins, gp120, the viral membrane fusion protein of human immunodeficiency virus (HIV), has been reported to promote cell signaling, and long-term surviving HIV-positive patients have a high incidence of developing PAH. This article describes the findings of the SARS-CoV-2 spike protein affecting lung vascular cells and explains how the spike protein possibly increases the incidence of PAH. Since the SARS-CoV-2 spike protein will be administered to millions of people as COVID-19 vaccines, it is critical to understand the biological effects of this protein on human cells to ensure that it does not promote long-term adverse health consequences.
Methyl (2E)-3-[3-Benzyl-2-(3-methoxy-3-oxoprop-1-yn-1-yl)-2-(1-naphthyl)imidazolidin-1-yl]acrylate
Authors: Golubenkova Alexandra , Golantsov Nikita , Voskressensky Leonid
Published: December 2020

Compounds with propargylamine moiety are useful synthetic precursors of several important classes of nitrogen-containing heterocycles. The title compound, methyl (2E)-3-[3-benzyl-2-(3-methoxy-3-oxoprop-1-yn-1-yl)-2-(1-naphthyl)imidazolidine-1-yl]acrylate, has been prepared by domino-reaction, employing easily available 1-benzyl-2-(1-naphthyl)-4,5-dihydro-1H-imidazole and methyl propiolate in a high 92% yield. The structure of title compound was determined using 1H-NMR, 13C-NMR, UV, FT-IR and HRMS (High-Resolution Mass Spectrometry).
N-(2-(1H-Indol-3-yl)ethyl)-2-(2-fluoro-[1,1′-biphenyl]-4-yl)propanamide
Authors: Manolov Stanimir , Ivanov Iliyan , Bojilov Dimitar
Published: December 2020

N-(2-(1H-Indol-3-yl)ethyl)-2-(2-fluoro-[1,1′-biphenyl]-4-yl)propanamide was prepared by a reaction between tryptamine and flurbiprofen, applying N,N’-Dicyclohexylcarbodiimide, as a coupling agent. The obtained new amide has a fragment similar to Brequinar, a compound used in SARS-CoV-2 treatment trials. The newly synthesized compound was fully analyzed and characterized via 1H, 13C-NMR, UV, IR, and mass spectral data.
Micro Fracture Behavior of Composite Honeycomb Sandwich Structure
Authors: Bi Guangjian , Yin Jianping , Wang Zhijun , Jia Zijian
Published: December 2020

To study the influence of structure size and composite forms on the mechanical properties of the composite double honeycomb sandwich structure, a composite double honeycomb sandwich structure was initially designed. The dynamic response of a composite double-layer honeycomb sandwich structure under high-speed impact was studied through theoretical analysis and numerical simulation. Ls-dyna software was used to simulate the initially designed composite structure. According to the numerical simulation results and the proposed method for calculating the fracture energy of the composite double honeycomb sandwich structure, the effects of different composite forms on the mechanical properties were analyzed. The results show that the proposed fracture energy calculation method can effectively describe the variation trend of the honeycomb structure and the micro-element fracture situation in the valid time. The fracture energy curve has a high sensitivity to cell density and material, and the strength of the top core has a great influence on the overall energy absorption. Compared with the traditional honeycomb protection structure, the energy absorption of the initially designed composite honeycomb sandwich structure was improved effectively.
Application of 3D Scanning as an Indirect Method to Analyze and Eliminate Errors on the Manufactured Yoke-Type Forgings Forged in SMED Device on Modernized Crank Press
Authors: Ziemba Jacek , Hawryluk Marek , Rychlik Marcin
Published: December 2020

This article proposes an indirect measurement method based on a dimensional and shape analysis of forgings for the evaluation of the manufacture and the proper operation of the key elements of the crank press, in which after modernization, a quick tool assembly based on SMED (Single Minute Exchange of Die) was implemented. As a result of the introduced changes aiming at improving the forging aggregate and increasing the production efficiency, errors were observed on the manufactured products-forgings in the form of twists and joggles. In order to solve the problem, a lot of advanced methods was used, including: dynamic system of deformation analysis, numerical modeling and as well as dimensional and shape analysis by 3d scanning. Despite the above, this approach (classic way) did not solve the problem. A proprietary method with the use of 3D reverse scanning was proposed, which allows to solve the problem of forgings errors. Based on the measurement results and analyses for a few variants of production cycles, the necessary changes were obtained, making it possible to minimize the errors and obtain proper products in respect of geometry and quality.
Design of Eutectic Hydrated Salt Composite Phase Change Material with Cement for Thermal Energy Regulation of Buildings
Authors: Wu Niuniu , Liu Lijie , Yang Zhiwei , Wu Yifan , Li Jinhong
Published: December 2020

An energy-efficient eutectic hydrated salt phase change material based on sodium carbonate decahydrate and disodium hydrogen phosphate dodecahydrate (SD) was prepared. Then, SD was encapsulated into expanded graphite (EG) to produce form-stable composite phase change materials (SD/E), which indicated a positive effect on preventing the leakage of SD, decreasing the supercooling and improving the thermal conductivity. SD/E was further tested for thermal efficiency by simulating the indoor environment with a house-like model which was composed of SD/E and magnesium oxychloride cement. The results showed an excellent thermal insulation effect. This exciting porous composite phase shift material reveals possible architectural applications because of the attractive thermos-physical properties of SD/E.
Modeling and Testing of Flexible Structures with Selected Planar Patterns Used in Biomedical Applications
Authors: Marsalek Pavel , Sotola Martin , Rybansky David , Repa Vojtech , Halama Radim , Fusek Martin , Prokop Jiri
Published: December 2020

Flexible structures (FS) are thin shells with a pattern of holes. The stiffness of the structure in the normal direction is reduced by the shape of gaps rather than by the choice of the material based on mechanical properties such as Young’s modulus. This paper presents virtual prototyping of 3D printed flexible structures with selected planar patterns using laboratory testing and computer modeling. The objective of this work is to develop a non-linear computational model evaluating the structure’s stiffness and its experimental verification; in addition, we aimed to identify the best of the proposed patterns with respect to its stiffness: load-bearing capacity ratio. Following validation, the validated computational model is used for a parametric study of selected patterns. Nylon—Polyamide 12—was chosen for the purposes of this study as an appropriate flexible material suitable for 3D printing. At the end of the work, a computational model of the selected structure with modeling of load-bearing capacity is presented. The obtained results can be used in the design of external biomedical applications such as orthoses, prostheses, cranial remoulding helmets padding, or a new type of adaptive cushions. This paper is an extension of the conference paper: “Modeling and Testing of 3D Printed Flexible Structures with Three-pointed Star Pattern Used in Biomedical Applications” by authors Repa et al.
Enhanced P-Type GaN Conductivity by Mg Delta Doped AlGaN/GaN Superlattice Structure
Authors: Zhao Ying , Xu Shengrui , Tao Hongchang , Zhang Yachao , Zhang Chunfu , Feng Lansheng , Peng Ruoshi , Fan Xiaomeng , Du Jinjuan , Zhang Jincheng , Hao Yue
Published: December 2020

A method of combining the AlGaN/GaN superlattices and Mg delta doping was proposed to achieve a high conductivity p-type GaN layer. The experimental results provided the evidence that the novel doping technique achieves superior p-conductivity. The Hall-effect measurement indicated that the hole concentration was increased by 2.06 times while the sheet resistivity was reduced by 48%. The fabricated green-yellow light-emitting diodes using the achieved high conductivity p-type GaN layer showed an 8- and 10-times enhancement of light output power and external quantum efficiency, respectively. The subsequent numerical calculation was conducted by using an Advanced Physical Model of Semiconductor Device to reveal the mechanism of enhanced device performance. This new doping technique offers an attractive solution to the p-type doping problems in wide-bandgap GaN or AlGaN materials.
Ultraviolet Light Treatment of Titanium Enhances Attachment, Adhesion, and Retention of Human Oral Epithelial Cells via Decarbonization
Authors: Nakhaei Kourosh , Ishijima Manabu , Ikeda Takayuki , Ghassemi Amirreza , Saruta Juri , Ogawa Takahiro
Published: December 2020

Early establishment of soft-tissue adhesion and seal at the transmucosal and transcutaneous surface of implants is crucial to prevent infection and ensure the long-term stability and function of implants. Herein, we tested the hypothesis that treatment of titanium with ultraviolet (UV) light would enhance its interaction with epithelial cells. X-ray spectroscopy showed that UV treatment significantly reduced the atomic percentage of surface carbon on titanium from 46.1% to 28.6%. Peak fitting analysis revealed that, among the known adventitious carbon contaminants, C–C and C=O groups were significantly reduced after UV treatment, while other groups were increased or unchanged in percentage. UV-treated titanium attracted higher numbers of human epithelial cells than untreated titanium and allowed more rapid cell spread. Hemi-desmosome-related molecules, integrin β4 and laminin-5, were upregulated at the gene and protein levels in the cells on UV-treated surfaces. The result of the detachment test revealed twice as many cells remaining adherent on UV-treated than untreated titanium. The enhanced cellular affinity of UV-treated titanium was equivalent to laminin-5 coating of titanium. These data indicated that UV treatment of titanium enhanced the attachment, adhesion, and retention of human epithelial cells associated with disproportional removal of adventitious carbon contamination, providing a new strategy to improve soft-tissue integration with implant devices.
Freeze–Thaw Resistance and Air-Void Analysis of Concrete with Recycled Glass–Pozzolan Using X-ray Micro-Tomography
Authors: Krstic Marija , Davalos Julio F. , Rossi Emanuele , Figueiredo Stefan C. , Copuroglu Oguzhan
Published: December 2020

Recent studies have shown promising potential for using Glass Pozzolan (GP) as an alternative supplementary cementitious material (SCM) due to the scarcity of fly ash and slag in the United States. However, comprehensive studies on the freeze–thaw (FT) resistance and air void system of mixtures containing GP are lacking. Therefore, this study aimed to evaluate GP’s effect on FT resistance and characterize mixtures with different GP contents, both macro- and microscopically. In this study, six concrete mixes were considered: Three mixes with 20%, 30% and 40% GP as cement replacements and two other comparable mixes with 30% fly ash and 40% slag, as well as a mix with 100% Ordinary Portland cement (OPC) as a reference. Concrete samples were prepared, cured and tested according to the ASTM standards for accelerated FT resistance for 1000 cycles and corresponding dynamic modulus of elasticity (Ed). All the samples showed minimal deterioration and scaling and high F/T resistance with a durability factor of over 90%. The relationships among FT resistance parameters, air-pressured method measurements of fresh concretes and air void analysis parameters of hardened concretes were examined in this study. X-ray micro-tomography (micro-CT scan) was used to evaluate micro-cracks development after 1000 freeze–thaw cycles and to determine spatial parameters of air voids in the concretes. Pore structure properties obtained from mercury intrusion porosimetry (MIP) and N2 adsorption method showed refined pore structure for higher cement replacement with GP, indicating more gel formation (C-S-H) which was verified by thermogravimetric analysis (TGA).
Design and Evaluation of a New Resin-Filled GFRP Pipe Connection System for Butt Splicing of FRP Bars
Authors: Huang Hui , Lian Jie , Li Jiaxing , Jia Bin , Meng Dong , Wu Zhizhong
Published: December 2020

Fiber-reinforced polymer (FRP) bars are one of the promising alternatives for steel bars used in concrete structures under corrosion or non-magnetic environments due to the unique physical properties of FRP materials. When compared with steel bars, FRP bars are difficult to be spliced in field application due to their anisotropy and low shear and compressive strengths. In view of this, the paper presents a new non-metallic connection system (i.e., resin-filled glass fiber-reinforced polymer (GFRP) pipe connection system) for the butt splicing of FRP bars. With the proposed connection system and a simplified trilinear interfacial bond-slip model, a set of design formulas were derived based on the requirement that the proposed connection system should provide a load transfer capacity beyond the tensile capacity of the spliced FRP bars (i.e., to fulfill the high tensile strength of FRP materials). Besides, considering the fabrication error-induced load transfer capacity reduction of the connection system in field application, a correction factor was introduced in the paper to compensate for the reduced load transfer capacity by increasing the FRP bar anchorage length. At last, to estimate the effectiveness of the proposed connection system and the derived design formulas, nine specimens were fabricated with a kind of commercially available basalt fiber-reinforced polymer (BFRP) bars and the designed connection system and tested under unidirectional tension to study their tensile performance. With the comparison between the tested and theoretical results, the effectiveness of the proposed connection system and the derived design formulas are verified.
New Specific and General Linearization Formulas of Some Classes of Jacobi Polynomials
Authors: Abd-Elhameed Waleed Mohamed , Ali Afnan
Published: December 2020

The main purpose of the current article is to develop new specific and general linearization formulas of some classes of Jacobi polynomials. The basic idea behind the derivation of these formulas is based on reducing the linearization coefficients which are represented in terms of the Kampé de Fériet function for some particular choices of the involved parameters. In some cases, the required reduction is performed with the aid of some standard reduction formulas for certain hypergeometric functions of unit argument, while, in other cases, the reduction cannot be done via standard formulas, so we resort to certain symbolic algebraic computation, and specifically the algorithms of Zeilberger, Petkovsek, and van Hoeij. Some new linearization formulas of ultraspherical polynomials and third-and fourth-kinds Chebyshev polynomials are established.
Improved Commercially Pure Titanium Obtained by Laser Directed Energy Deposition for Dental Prosthetic Applications
Authors: Barro Óscar , Arias-González Felipe , Lusquiños Fernando , Comesaña Rafael , del Val Jesús , Riveiro Antonio , Badaoui Aida , Gómez-Baño Félix , Pou Juan
Published: December 2020

The objective of this study was to evaluate the viability of the cp-Ti obtained through the laser-directed energy deposition (LDED) technique as a material for dental prostheses through an evaluation of the microstructural, mechanical, and electrochemical properties. Additionally, the material resulting from LDED is also compared with the same alloy employed for milling in the dental restorative industry. The results obtained show that both materials have good overall performance for biomedical applications according to the ISO 22674 and ISO 10271 dentistry standards. Both materials have high corrosion resistance, typical of this alloy. However, commercially pure titanium grade 4 obtained by LDED present a higher mechanical performance than the ones resulting from the milling technique: 7% increment of ultimate tensile strength, 12.9% increment of elongation after fracture and 30% increment of toughness. This improved mechanical performance can be attributed to microstructure modification inherent to the LDED process.